Emerging role of Mycoplasma pneumoniae and Chlamydia pneumoniae in paediatric respiratory-tract infections

Challenges in the treatment of pediatric Mycoplasma pneumoniae pneumonia

Mycoplasma pneumoniae (MP) is an important cause of community-acquired pneumonia in children and young adolescents. Despite macrolide antibiotics effectiveness as a first-line therapy, persistence of fever and/or clinical deterioration sometimes may complicate treatment and may even lead to severe systemic disease. To date, there is no consensus on alternative treatment options, optimal dosage, and duration for treating severe, progressive, and systemic MP pneumonia after macrolide treatment failure. Macrolide-resistant MP pneumonia and refractory MP pneumonia are the two major complex conditions that are clinically encountered. Currently, the vast majority of MP isolates are resistant to macrolides in East Asia, especially China, whereas in Europe and North America, whereas in Europe and North America prevalence is substantially lower than in Asia, varying across countries. The severity of pneumonia and extrapulmonary presentations may reflect the intensity of the host's immune reaction or the dissemination of bacterial infection. Children infected with macrolide-resistant MP strains who receive macrolide treatment experience persistent fever with extended antibiotic therapy and minimal decrease in MP-DNA load. Alternative second-line agents such as tetracyclines (doxycycline or minocycline) and fluoroquinolones (ciprofloxacin or levofloxacin) may lead to clinical improvement after macrolide treatment failure in children. Refractory MP pneumonia reflects a deterioration of clinical and radiological findings due to excessive immune response against the infection. Immunomodulators such as corticosteroids and intravenous immunoglobulin (IVIG) have shown promising results in treatment of refractory MP pneumonia, particularly when combined with appropriate antimicrobials. Corticosteroid-resistant hyperinflammatory MP pneumonia represents a persistent or recrudescent fever despite corticosteroid therapy with intravenous methylprednisolone at standard dosage.

CONCLUSION

 This report summarizes the clinical significance of macrolide-resistant and refractory MP pneumonia and discusses the efficacy and safety of alternative drugs, with a stepwise approach to the management of MP pneumonia recommended from the viewpoint of clinical practice.

WHAT IS KNOWN

• Although MP pneumonia is usually a benign self-limited infection with response macrolides as first line therapy, severe life-threatening cases may develop if additional treatment strategies are not effectively implemented. • Macrolide-resistant and refractory MP pneumonia are two conditions that may complicate the clinical course of MP pneumonia, increasing the risk for exacerbation and even death.

WHAT IS NEW

• This report summarizes the clinical relevance of macrolide-resistant and refractory MP pneumonia and discusses the efficacy and safety of alternative drug therapies. • A practical stepwise approach to the management of MP pneumonia is developed based on a comprehensive analysis of existing evidence and expert opinion.

Etiology and clinical features of infection-associated plastic bronchitis in children

OBJECTIVE

To investigate the etiological characteristics of plastic bronchitis (PB) caused by pulmonary infections in children and to identify any differences in the clinical features of PB cases caused by different pathogens.

METHOD

We collected data on children diagnosed with PB and admitted to the Respiratory Department at Soochow University Children's Hospital between July 2021 and March 2023 utilizing electronic bronchoscopy. We analyzed clinical characteristics and the species of pathogens causing the illness in these children.

RESULT

A total of 45 children were enrolled. The main clinical symptoms observed were cough (100%), fever (80%), shortness of breath (28.9%), and wheezing (20.0%). Pathogens were identified in 38 (84.4%) patients. Mycoplasma pneumoniae (MP) had the highest detection rate at 53.3%, followed by the Boca virus at 26.7%. MP-induced PB typically occurs in older children with an average age of 7.46 ± 2.36 years, with the main symptoms including high fever (85.7%) and local hyporespiration (42.9%). In contrast, Boca virus-induced PB tends to occur in younger children, with the main symptoms of moderate fever (54.5%), and wheezing (54.5%). The MP group exhibited a higher incidence of both internal and external pulmonary complications, including pleural effusion (42.9%), elevated aspartate aminotransferase (52.4%), lactic dehydrogenase (76.2%), and D-D dimer (90.5%). Conversely, the Boca virus group primarily showed pulmonary imaging of atelectasis (81.8%), with no pleural effusion. The average number of bronchoscopic interventions in the MP group was 2.24 ± 0.62, which was significantly higher than that required in the Boca virus group (1.55 ± 0.52). During the second bronchoscopy, 57.1% of children in the MP group still had visible mucus plugs, while none were observed in the Boca virus group.

CONCLUSION

MP and Boca virus are the primary pathogens responsible for PB among children. The clinical manifestations of PB typically vary significantly based on the pathogen causing the condition.

Etiologies of Acute Bronchiolitis in Children at Risk for Asthma, with Emphasis on the Human Rhinovirus Genotyping Protocol

This research aims to determine acute bronchiolitis' causative virus(es) and establish a viable protocol to classify the Human Rhinovirus (HRV) species. During 2021-2022, we included children 1-24 months of age with acute bronchiolitis at risk for asthma. The nasopharyngeal samples were taken and subjected to a quantitative polymerase chain reaction (qPCR) in a viral panel. For HRV-positive samples, a high-throughput assay was applied, directing the VP4/VP2 and VP3/VP1 regions to confirm species. BLAST searching, phylogenetic analysis, and sequence divergence took place to identify the degree to which these regions were appropriate for identifying and differentiating HRV. HRV ranked second, following RSV, as the etiology of acute bronchiolitis in children. The conclusion of the investigation of all available data in this study distributed sequences into 7 HRV-A, 1 HRV-B, and 7 HRV-C types based on the VP4/VP2 and VP3/VP1 sequences. The nucleotide divergence between the clinical samples and the corresponding reference strains was lower in the VP4/VP2 region than in the VP3/VP1 region. The results demonstrated the potential utility of the VP4/VP2 region and the VP3/VP1 region for differentiating HRV genotypes. Confirmatory outcomes were yielded, indicating how nested and semi-nested PCR can establish practical ways to facilitate HRV sequencing and genotyping.

Antibiotic prescriptions for children with lower respiratory tract infections fell from 2014 to 2020, but misuse was still an issue

AIM

We evaluated main trends in antibiotic prescriptions for children with lower respiratory tract infection (LRTI) by Terveystalo, Finland's largest private healthcare company.

METHODS

The study comprised of 89,359 children aged 0-17 years (57.2% boys) who visited Terveystalo primary care clinics from 2014 to 2020 with LRTI. The data were assessed by age, study year, location, the doctor's speciality and whether the diagnosis was bronchitis or community-acquired pneumonia (CAP).

RESULTS

There were gradual decreases in overall antibiotic prescription rates during the study period (37.0% in 2014 vs. 20.1% in 2020) and in prescribed macrolides (16.8% vs. 7.5%). Altogether, 31.3% of 72,737 children with bronchitis and 22.5% of those 16,622 with CAP-received antibiotics. Macrolides were the most frequently prescribed antibiotics for bronchitis, at more than 40%, without any substantial relative decrease during the study. Costs of antibiotics increased from 2014 to 2016 and then decreased in line with the reduction in prescriptions. However, there was still a marked overuse of antibiotics, especially macrolides, for children with bronchitis. The relative use of amoxicillin for CAP increased from 41.4% to 65.4% between 2016 and 2020, in line with current guidelines.

CONCLUSION

Despite an overall reduction in prescribed antibiotics, some antibiotics were still overused, particularly macrolides for bronchitis.

The remaining unsolved problems for rational antibiotic therapy use in pediatric community-acquired pneumonia

INTRODUCTION

Despite availability of several official guidelines, not all the problems related to the most effective and safe use of antibiotics in children with community-acquired pneumonia (CAP) have been solved. Presently, too many children receive unneeded antibiotics or, when antibiotics are mandatory, the choice of the drug is not appropriate.

AREAS COVERED

In this paper, the authors discuss the remaining unsolved problems for rational antibiotic therapy use in pediatric community-acquired pneumonia and provide their expert perspectives.

EXPERT OPINION

Further improvement in pediatric CAP management could be derived from physician education on antibiotic use and a larger use, particularly in office practice, of point of care testing or new technologies (i.e. artificial intelligence) to define etiology of a lower respiratory infection. However, recommendations regarding the duration of antibiotic therapy vary largely because of the absence of reliable data on the optimal CAP treatment according to the bacterial etiology of the disease, its severity, and child characteristics. Available evidence seems to confirm that a short course of antibiotics, approximately 5 days, can be effective and lead to results not substantially different from those obtained with prolonged-course antibiotic therapy, at least in patients with mild to moderate disease.

Update on the Epidemiology of Macrolide-Resistant Mycoplasma pneumoniae in Europe: A Systematic Review

Macrolide-resistant Mycoplasma pneumoniae (MR-MP) infections cause upper and lower respiratory tract infections in both children and adults, and are characterized by a longer duration of symptoms. Here, we undertook a systematic review of studies on MR-MP in Europe. The review meets PRISMA guidelines. The PubMed, Scopus, and Science Direct databases were searched using suitable keywords to identify relevant studies published from 2010 to 2021; 21 studies were included. Overall, a low level of MR-MP spread was reported in Europe. MR-MP spread increased during epidemic waves registered in Europe, particularly in Italy and Scotland, where the highest MR-MP infection rates were registered during the 2010–2011 epidemic. By contrast, no MR-MP infections were reported in Finland and the Netherlands. Continued monitoring of MR-MP in Europe is needed to maintain the low rates of infection. Moreover, a coordinated and structured pan-European surveillance program adequate for public health surveillance is advisable, with the purpose of containing the spread of antimicrobial resistance.

Clinical Evaluation of a Novel Point-of-Care Assay To Detect Mycoplasma pneumoniae and Associated Macrolide-Resistant Mutations

The recent increase in macrolide-resistant Mycoplasma pneumoniae in Asia has become a continuing problem. A point-of-care testing method that can quickly detect M. pneumoniae and macrolide-resistant mutations (MR mutations) is critical for proper antimicrobial use. Smart Gene (Mizuho Medy Co., Ltd., Tosu City, Saga, Japan) is a compact and inexpensive fully automatic gene analyzer that combines amplification with PCR and the quenching probe method to specify the gene and MR mutations simultaneously. We performed a clinical evaluation of this device and its reagents on pediatric patients with suspected M. pneumoniae respiratory infections and evaluated the impact of the assay on antimicrobial selection. Using real-time PCR as a comparison control, the sensitivity of Smart Gene was 97.8% (44/45), its specificity was 93.3% (98/105), and its overall concordance rate was 94.7% (142/150). The overall concordance rate of Smart Gene diagnosis of MR mutations in comparison with sequence analysis was 100% (48/48). The ratio of MR mutations was significantly higher at high-level medical institutions than at a primary medical clinic (P = 0.023), and changes in antibiotic therapy to drugs other than macrolides were significantly more common in patients with MR mutations (P = 0.00024). Smart Gene demonstrated excellent utility in the diagnosis of M. pneumoniae and the selection of appropriate antimicrobials for MR mutations at primary medical institutions, which play a central role in community-acquired pneumonia care. The use of this device may reduce referrals to high-level medical institutions for respiratory infections, thereby reducing the medical and economic burdens on patients.

Proteomic and mechanistic study of Qingxuan Tongluo formula and curcumin in the treatment of Mycoplasma pneumoniae pneumonia

OBJECTIVE

Mycoplasma pneumoniae (MP) is the only pathogen in the Mycoplasma family that can cause respiratory symptoms, including acute upper respiratory tract infection and bronchitis, which are often attributed to Mycoplasma pneumoniae pneumonia (MPP). MPP is one of the diseases that commonly affects the pediatric respiratory system, but its pathogenesis is unclear. This study investigated the therapeutic effects and mechanisms of Qingxuan Tongluo formula and its main component, curcumin, on MPP.

METHODS

A mouse model of MPP was obtained by nasal drip of the MP strain. The effects of Qingxuan Tongluo formula and curcumin on the treatment of MPP were studied. The proteomic profiles of the alveolar lavage fluid of mice in the model group, Qingxuan Tongluo formula group and curcumin group were evaluated by LC-MS/MS. ELISA and immunohistochemistry were used to verify the possible presence of MP infection biomarkers and drug target proteins.

RESULTS

Compared with the mice in the model group, the MPP mice in the Qingxuan Tongluo formula group had significantly reduced fever and cough and prolonged the cough incubation period. Moreover, the pulmonary pathology of the MPP mice was significantly improved, and the lung histopathological score was decreased. After treatment with Qingxuan Tongluo formula and curcumin, the functional and pathway abnormalities caused by MP were mainly inhibited. Levels of HSP90AA1, GRP94, ENO1 and PLG expression were verified by ELISA and immunohistochemistry.

CONCLUSION

Qingxuan Tongluo formula significantly reduced fevers and cough and prolonged the cough incubation period of MPP mice. Qingxuan Tongluo formula and curcumin significantly improved the pathological changes in lung tissue caused by MP infection. Proteomics analyses indicated that Qingxuan Tongluo formula and curcumin may have therapeutic effects on MPP by regulating energy metabolism, relieving oxidative stress and activating the fibrinolytic system. ENO1 and PLG were found to be potential drug targets.

Accurate, rapid and low-cost diagnosis of Mycoplasma pneumoniae via fast narrow-thermal-cycling denaturation bubble-mediated strand exchange amplification

Mycoplasma pneumoniae is a strong infectious pathogen that may cause severe respiratory infections. Since this pathogen may possess a latent period after infection, which sometimes leads to misdiagnosis by traditional diagnosis methods, the establishment of a rapid and sensitive diagnostic method is crucial for transmission prevention and timely treatment. Herein, a novel detection method was established for M. pneumoniae detection. The method, which improves upon a denaturation bubble-mediated strand exchange amplification (SEA) that we developed in 2016, is called accelerated SEA (ASEA). The established ASEA achieved detection of 1% M. pneumoniae genomic DNA in a DNA mixture from multiple pathogens, and the limit of detection (LOD) of ASEA was as low as 1.0 × 10^-17 M (approximately 6.0 × 10³ copies/mL). Considering that the threshold of an asymptomatic carriage is normally recommended as 1.0 × 10⁴ copies/mL, this method was able to satisfy the requirement for practical diagnosis of M. pneumoniae. Moreover, the detection process was finished within 20.4 min, significantly shorter than real-time PCR and SEA. Furthermore, ASEA exhibited excellent performance in clinical specimen analysis, with sensitivity and specificity of 96.2% and 100%, respectively, compared with the "gold standard" real-time PCR. More importantly, similar to real-time PCR, ASEA requires only one pair of primers and ordinary commercial polymerase, and can be carried out using a conventional fluorescence real-time PCR instrument, which makes this method low-cost and easy to accomplish. Therefore, ASEA has the potential for wide use in the rapid detection of M. pneumoniae or other pathogens in large numbers of specimens. Graphical abstract.

The correlation between vitamin a status and refractory Mycoplasma Pneumoniae pneumonia (RMPP) incidence in children

Background

Vitamin A plays a pivotal role in respiratory infection, accurate estimation of vitamin A status was recommended in planning and implementing interventions. As infections affect serum vitamin A productions, the real status need to be adjusted by acute phase protein (APP). Mycoplasma pneumoniae is an important cause of respiratory infection in children, the association between vitamin A concentrations and refractory Mycoplasma pneumoniae pneumonia (RMPP) remains unclear.

Methods

181 MPP patients were enrolled in this retrospective study, adjusted vitamin A concentrations and other parameters were compared between RMPP and general-MPP (GMPP) patients. Multivariate logistic regression test was performed to evaluate the association between vitamin A levels and RMPP incidence, linear correlation tests were applied to evaluate correlation between vitamin A concentrations and fever duration, length of stay (LOS).

Results

Vitamin A concentrations in RMPP group were significantly lower than those in GMPP patients (P < 0.05), vitamin A (OR = 0.795, 95% C. I 0.669–0.946) and CRP (OR = 1.050, 95% C. I 1.014–1.087) were independently associated with RMPP incidence. Linear correlation tests found vitamin A concentrations were negatively correlated with fever duration and LOS (P < 0.001).

Conclusions

Serum vitamin A concentrations were independently associated with RMPP incidence, which may correlate with reduced incidence of RMPP.

Serum Cytokines and FeNO in School-Aged Children with Mycoplasma pneumoniae Pneumonia

Background

Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) that is particularly prevalent in school-aged children. This study explored the potential involvement of cytokines in children with Mycoplasma pneumoniae pneumonia (MPP) infection.

Material/Methods

Children aged 3–7 years who were hospitalized due to CAP infection were enrolled and divided into 2 groups: an MPP group (n=33) and a NMPP group (n=38), along with 21 age-matched healthy controls. Clinical characteristics and laboratory data were recorded. Serum levels of IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 were assessed using Luminex xMAP technology. Correlation analysis and ROC curves analysis were also performed to further explore the role of these detected cytokines in CAP.

Results

Compared with the healthy controls, the serum expression of IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 were significantly higher in the MPP and NMPP groups. Furthermore, serum IL-18 expression was found to be significantly correlated with lgE, FeNO, IL-5, IL-8, and IL-13 concentrations. Significant differences were also observed between the MPP group and NMPP group patients in levels of IL-18, IL-5, and IL-6, and further ROC analysis showed that the area under the curve (AUC) of IL-18 and IL-5 were 0.813 (95% CI: 0.710–0.917; P<0.01) and 0.844 (95% CI: 0.756–0.933; P<0.01), respectively.

Conclusions

IL-18, IL-33, IFN-γ, IL-5, IL-6, IL-8, and IL-13 serum levels showed significant differences in children with CAP. IL-18 and IL-5 were much higher in the MPP group compared to the NMPP group patients, whereas IL-6 levels were significantly lower in these 2 groups.

How does one choose the appropriate pharmacotherapy for children with lower respiratory tract infections?

INTRODUCTION

The definition of acute lower respiratory tract infection (LRTI) includes any infection involving the respiratory tract below the level of the larynx. In children, the most common acute LRTIs, and those with the greatest clinical relevance, are community-acquired pneumonia (CAP), bronchiolitis, bronchitis and tuberculosis (TB). The clinical relevance of LRTIs implies that they must be addressed with the most effective therapy. Antibiotics and antivirals play an essential role in this regard.

AREAS COVERED

In this paper, the most recent advances in the drug treatment of LRTIs in children are discussed.

EXPERT OPINION

Although LRTIs are extremely common and one of the most important causes of hospitalization and death in children, anti-infective therapy for these diseases remains unsatisfactory. For CAP and BR, the most important problem is the overuse and misuse of antibiotics; for BCL, the lack of drugs with demonstrated efficacy, safety and tolerability; for TB, the poor knowledge on the true efficacy and safety of the new drugs specifically planned to overcome the problem of MDR M. tuberculosis strains. There is still a long way to go for the therapy of pediatric LRTIs to be considered satisfactory.

Mycoplasma pneumoniae pneumonia associated thrombosis at Beijing Children's hospital

Background

With the increase of awareness of mycoplasma pneumoniae pneumonia (MPP), we found thrombosis in severe MPP (SMPP) was not rare. The aim of the study was to investigate the clinical characteristics, treatment, and long-term prognosis of MPP-associated thrombosis.

Methods

We retrospectively reviewed the medical records of 43 children with MPP-associated thrombosis between January 2013 and June 2019 at Beijing Children’s Hospital. The results of blood coagulation studies, autoimmune antibody, thrombophilia screening, contrast-enhanced lung computed tomography, echocardiography, and blood vessel ultrasonography were analyzed, as were treatment outcomes.

Results

Forty-two patients were diagnosed with SMPP. D-dimer was higher than 5.0 mg/L in 58.1% (25/43) of patients. The mean D-dimer level was 11.1 ± 12.4 mg/L. Anticardiolipin-IgM was positive in 60.0% of patients, β2-glycoprotein-IgM in 64.0%, and lupus anticoagulant in 42.1%. Chest imaging revealed pulmonary consolidation with lobe distribution in all patients (2/3–1 lobe in 10 patients, > 1 lobe in 29 patients). In our experience, thrombosis can occur in a vessel of any part of the body, and it can be initially detected as late as 31 days after disease onset. Thrombosis in the brain and abdomen can occur early, at 5 days after disease onset. Pulmonary vessels were the most commonly involved sites in the current study, and accordingly chest pain was the most common symptom (32.6%), followed by neurological symptoms (14.0%) and abdominal pain (9.3%). Thirty-five percent of patients were asymptomatic with regard to thrombosis. All patients underwent anticoagulant therapy, and thrombus absorption took > 3 months in most patients. All patients were followed until October 2019, at which time 41 were asymptomatic and 2 had mild recurrent cough.

Conclusions

SMPP with pulmonary consolidation (> 2/3 lobe) was the most strongly associated risk factor for thrombosis. Thrombosis-associated symptoms may be subtle, even absent. Elevated D-dimer, specifically > 11.1 mg/L (even > 5.0 mg/L), would assist in the early diagnosis of thrombosis. The long-term prognosis of thrombosis was good after timely administration of anticoagulant therapy.

The Association Between Mycoplasma pneumoniae and Chlamydia pneumoniae, a Life-Threatening Condition in Small Children-A Case Report and a Review of the Literature

Mycoplasma pneumoniae (MP) and Chlamydia pneumoniae (CP) are two atypical pathogens that may result in mild, moderate or severe acute respiratory infections. We report the case of a 2 years and 9-month-old male child admitted with prolonged fever, dry cough, and shortness of breath for which he underwent symptomatic treatment. The laboratory tests showed leukocytosis with neutrophilia, anemia, and elevated inflammatory biomarkers and the thoracic radiography revealed pleural effusion raising the suspicion of inferior right pneumonia. Although we the initial evolution was favorable being treated with 3rd class cephalosporin and Oxacillin, on the 8th day of admission the fever and the acute phase reactants levels increased as well as the quantity of the pleural effusion, requiring surgical drainage. We ruled out lung tuberculosis, but we identified positive IgM for both MP and CP. Based on these findings we changed the antibiotic therapy on Levofloxacin for 10 days with favorable evolution. MP and CP are two atypical pathogen that are difficult to be diagnosed due to their slow-growing pattern. Despite their self-limiting feature, the association between them might carry a vital risk in small children, especially in the lack of a proper and timely diagnosis.

A Peculiar Case of Pneumonia due to Mycoplasma pneumoniae in a Child with Cystic Fibrosis and Sensibilization to Aspergillus fumigatus

Aspergillus fumigatus plays a major role in pulmonary exacerbations in patients with cystic fibrosis. The most common A. fumigatus diseases are those based on immune-mediated response to A. fumigatus antigens; including allergic bronchopulmonary aspergillosis (ABPA). In this condition; the presence of A. fumigatus in the lower respiratory tract triggers an IgE-mediated hypersensitivity response that causes airway inflammation; bronchospasms; and bronchiectasis. This case report describes a ten-year-old male patient suffering from cystic fibrosis (CF) in whom the diagnosis of ABPA occurred in association with pneumonia due to Mycoplasma pneumoniae more than two weeks after hospitalization. This case is a good example of how difficult the identification of ABPA in CF patients can be and highlights that ABPA can occur in association with co-infections due to other pathogens. In order to avoid the risk of a late ABPA diagnosis, it is imperative that the diagnostic criteria guidelines are reviewed and standardized.

Correlation between chest radiographic findings and clinical features in hospitalized children with Mycoplasma pneumoniae pneumonia

Background

Radiologic evaluation of children with Mycoplasma pneumoniae is important for diagnosis and management.

Objective

To investigate the correlation between chest radiographic findings and the clinical features in children with Mycoplasma pneumoniae pneumonia.

Materials and methods

This study included 393 hospitalized children diagnosed with M. pneumoniae pneumonia between January 2000 and August 2016. Their clinical features and chest radiographs were reviewed. Radiographic findings were categorized and grouped as consolidation group (lobar or segmental consolidation) and non-consolidation group (patchy infiltration, localized reticulonodular infiltration, or parahilar peribronchial infiltration).

Results

Lobar or segmental consolidation (37%) was the most common finding, followed by parahilar or peribronchial infiltration (27%), localized reticulonodular infiltration (21%) and patchy infiltration (15%). The consolidation group was more frequently accompanied by pleural effusions (63%), compared to the non-consolidation group (16%). Compared with patients in the non-consolidation group, those in the consolidation group were associated with a significantly higher rate of hypoxia, tachypnea, tachycardia, extrapulmonary manifestations, prolonged fever, and longer periods of anti-mycoplasma therapy and hospitalization. Lobar or segmental consolidation was significantly more frequent in children ≥5 years old (44%) compared with children 2–5 years old (34%) and <2 years old (13%). Parahilar peribronchial infiltration was significantly more frequent in children <2 years old (56%) compared with children 2–5 years old (32%) and ≥5 years old (18%).

Conclusion

The chest radiographic findings of children with M. pneumoniae pneumonia correlate well with the clinical features. Consolidative lesions were frequently observed in older children and were associated with more severe clinical features.

The Clinical Presentation of Pediatric Mycoplasma pneumoniae Infections-A Single Center Cohort

BACKGROUND

Mycoplasma pneumoniae (MP) is a major cause of community-acquired upper and lower respiratory infections in school-age children; however, there is increasing recognition that younger children are also affected. Clinical manifestations vary from asymptomatic, to severe complicated pneumonia sometimes with extrapulmonary manifestations.

METHODS

We reviewed the medical records of all MP positive pediatric patients admitted to the Hadassah-Hebrew University Medical Center. MP positive case was defined if MP polymerase chain reaction was positive from an oropharyngeal swab sent from 2007 to 2017.

RESULTS

During the study period, we identified 353 MP positive pediatric cases, of which 51.3% (181 of 353) were younger than 6 years old. Full clinical data were available for 332 of 353 (94%). The median age was 5.7 years (range, 3 weeks to 18 years). Disease presentation differed between younger and older children. Children older than 6 years were more likely to have chest radiograph confirmed pneumonia (66% vs. 52%; P = 0.009), while younger children were more likely to have other respiratory manifestations (37% vs. 25%; P = 0.017). The duration of hospitalization and pediatric intensive care unit admission rate, however, did not differ between age groups. The rate of extrapulmonary manifestations were also similar.

CONCLUSIONS

MP-associated infection is a significant cause of hospitalization in the pediatric population including younger children (<6 years old). However, the clinical presentation in younger age is less typical than is thought. These findings should prompt clinicians to consider MP infections also in children younger than 6 admitted with fever even without pneumonia.

Multiplex Platforms for the Identification of Respiratory Pathogens: Are They Useful in Pediatric Clinical Practice?

Respiratory tract infections (RTIs) are extremely common especially in the first year of life. Knowledge of the etiology of a RTI is essential to facilitate the appropriate management and the implementation of the most effective control measures. This perspective explains why laboratory methods that can identify pathogens in respiratory secretions have been developed over the course of many years. High-complexity multiplex panel assays that can simultaneously detect up to 20 viruses and up to four bacteria within a few hours have been marketed. However, are these platforms actually useful in pediatric clinical practice? In this manuscript, we showed that these platforms appear to be particularly important for epidemiological studies and clinical research. On the contrary, their routine use in pediatric clinical practice remains debatable. They can be used only in the hospital as they require specific equipment and laboratory technicians with considerable knowledge, training, and experience. Moreover, despite more sensitive and specific than other tests routinely used for respiratory pathogen identification, they do not offer significantly advantage for detection of the true etiology of a respiratory disease. Furthermore, knowledge of which virus is the cause of a respiratory disease is not useful from a therapeutic point of view unless influenza virus or respiratory syncytial virus are the infecting agents as effective drugs are available only for these pathogens. On the other hand, multiplex platforms can be justified in the presence of severe clinical manifestations, and in immunocompromised patients for whom specific treatment option can be available, particularly when they can be used simultaneously with platforms that allow identification of antimicrobial resistance to commonly used drugs. It is highly likely that these platforms, particularly those with high sensitivity and specificity and with low turnaround time, will become essential when new drugs effective and safe against most of the respiratory viruses will be available. Further studies on how to differentiate carriers from patients with true disease, as well as studies on the implications of coinfections and identification of antimicrobial resistance, are warranted.

Acute Bronchitis Caused by Bordetella Pertussis Possibly Co-Infected with Mycoplasma Pneumoniae

BACKGROUND Mycoplasma pneumoniae and Bordetella pertussis are among the causative pathogens of human acute bronchitis, which usually has mild symptoms. However, if there is a co-infection, the symptoms often can be prolonged and occasionally can lead to severe respiratory complications. CASE REPORT A 49-year-old Japanese female, who had not been vaccinated for B. pertussis, developed a persistent productive cough which became vigorous, and occasionally caused difficulty breathing and vomiting. Since serum IgM to M. pneumoniae was positive and IgG to B. pertussis was significantly elevated, and there were no findings of pneumonia on a chest x-ray film, we made a diagnosis of acute bronchitis caused by B. pertussis with possible co-infection with M. pneumoniae. The use of garenoxacin, a quinolone derivative, failed to work; however, a macrolide antibiotic clarithromycin dramatically improved her symptoms shortly after its administration. CONCLUSIONS In this patient case, because of the lymphocyte-stimulatory nature of M. pneumoniae and B. pertussis, an increased immunological response was likely to be involved in the pathogenesis of the symptoms. The immunosuppressive effect of clarithromycin was considered to repress the increased lymphocyte activity, facilitating the remission of the disease.

Pathogenesis and Treatment of Neurologic Diseases Associated With Mycoplasma pneumoniae Infection

Mycoplasma pneumoniae is mainly recognized as a respiratory pathogen, although it is associated with the development of several extra-respiratory conditions in up to 25% of the cases. Diseases affecting the nervous system, both the peripheral (PNS) and the central nervous system (CNS), are the most severe. In some cases, particularly those that involve the CNS, M. pneumoniae-related neuropathies can lead to death or to persistent neurologic problems with a significant impact on health and a non-marginal reduction in the quality of life of the patients. However, the pathogenesis of most of the M. pneumoniae-related neuropathies remains undefined. The main aim of this paper is to discuss what is presently known regarding the pathogenesis and treatment of the most common neurologic disorders associated with M. pneumoniae infection. Unfortunately, the lack of knowledge of the true pathogenesis of most of the cases of M. pneumoniae-mediated neurological diseases explains why treatment is not precisely defined. However, antibiotic treatment with drugs that are active against M. pneumoniae and able to pass the blood-brain barrier is recommended, even though the best drug, dosage, and duration of therapy have not been established. Sporadic clinical reports seem to indicate that because immunity plays a relevant role in the severity of the condition and outcome, attempts to reduce the immune response can be useful. However, further studies are needed before the problem of the best therapy for M. pneumoniae-mediated neurological diseases can be efficiently solved.

Contribution of Co-detected Respiratory Viruses and Patient Age to the Clinical Manifestations of Mycoplasma Pneumoniae Pneumonia in Children

BACKGROUND

The clinical spectrum of Mycoplasma pneumoniae pneumonia is widely variable. This study evaluated the clinical manifestations of M. pneumoniae pneumonia in children of different age groups and by the presence of co-detected respiratory virus.

METHODS

This study included children hospitalized with M. pneumoniae pneumonia between 2010 and 2015. At the time of pneumonia diagnosis, a nasopharyngeal aspirate was analyzed for respiratory viruses by reverse transcription-polymerase chain reaction (RT-PCR). The clinical manifestations and laboratory findings were reviewed from medical records.

RESULTS

Of the 286 children with M. pneumoniae pneumonia, 84 (29.4%) had a co-detected respiratory virus, with the highest co-detection rate in young children (51.9% of children <2 years; P = 0.002). In children <2 years, with and without co-detected virus, wheezing occurred in 35.7% and 15.4%, respectively. Among the 202 children without any virus detected, only 6.4% were <2 years. These young children showed fewer median days of fever than the children ≥2 years (8 vs. 11 days; P = 0.022). Children ≥2 years tended to have accompanying skin rashes (21.7% vs.7.7%; P = 0.310) and elevated liver enzymes (21.7% vs. 0%; P = 0.075) more frequently than children <2 years. Only 53.8% of the patients <2 years were treated with macrolide compared with 94.1% of the patients ≥2 years (P < 0.001).

CONCLUSIONS

The clinical manifestations of M. pneumoniae pneumonia in young children are milder than those in older children. A high prevalence of co-detected respiratory virus in young children suggests that virus might play a role in making pneumonia clinically apparent in this age group.

Monitoring adherence to guidelines of antibiotic use in pediatric pneumonia: the MAREA study

Background

Children are the most vulnerable population exposed to the use of antibiotics often incorrectly prescribed for the treatment of infections really due to viruses rather than to bacteria. We designed the MAREA study which consisted of two different studies: i) a surveillance study to monitor the safety/efficacy of the antibiotics for the treatment of pneumonia (CAP), pharyngotonsillitis and acute otitis media in children younger than 14 yrs old, living in Liguria, North-West Italy and ii) a pre−/post-interventional study to evaluate the appropriateness of antibiotic prescription for the treatment these infections. In this paper, we show only results of the appropriateness study about the antibiotic prescription for the treatment of pneumonia.

Methods

Patients included in this study met the following inclusion criteria: i) admission to the Emergency/Inpatient Dpt/outpatient clinic of primary care pediatricians for pneumonia requiring antibiotics, ii) informed written consent. The practice of prescribing antibiotics was evaluated before-and-after a 1 day-educational intervention on International/National recommendations.

Results

Global adherence to guidelines was fulfilled in 45%: main reason for discordance was duration (shorter than recommended). Macrolide monotherapy and cephalosporins were highly prescribed; ampicillin/amoxicillin use was limited. 61% of patients received >1 antibiotic; parenteral route was used in 33%. After intervention, i) in all CAP, cephalosporin prescription decreased (−23%) and the inappropriate macrolide prescriptions was halved and, ii) in not hospitalized CAP (notH-CAP), macrolides were prescribed less frequently (−25%) and global adherence to guidelines improved (+39%); and iii) in H-CAP antibiotic choice appropriateness increase.

Conclusion

Prescribing practices were sufficiently appropriate but widespread preference for multidrug empirical regimens or macrolide in monotherapy deserve closer investigation.

Serological Analysis and Drug Resistance of Chlamydia pneumoniae and Mycoplasma pneumoniae in 4500 Healthy Subjects in Shenzhen, China

Objective

To understand the prevalence and distribution of Chlamydia pneumoniae (CP) and Mycoplasma pneumoniae (MP) in the population and to provide a basis for the prevention and treatment of respiratory tract infection.

Methods

This study included a total of 4500 healthy subjects who were given physical examination in Shenzhen People's Hospital from January to December in 2016. Venous blood was drawn from people to detect the MP- and CP-specific IgG and IgM in the serum using chemiluminescence immunoassay (CLIA). The relationship of MP and CP infections with patient age, seasons, and percentage of infections was analyzed.

Conclusion

CP and MP cause high rate of asymptomatic infection, which may be associated with the high incidence of CP and MP infection, especially in children and the elderly population. Therefore, the implementation of effective and practical prevention measures has become an urgent need. MP culture and drug sensitivity test should be performed as early as possible in patients with manifested MP infections in order to ensure timely and proper treatment and to reduce the emergence of drug-resistant strains.

A comparison study between GeXP-based multiplex-PCR and serology assay for Mycoplasma pneumoniae detection in children with community acquired pneumonia

Background

Diagnosis of community-acquired pneumonia (CAP) caused by Mycoplasma pneumoniae (Mp) in children has been hampered by difficulty in obtaining convalescent serum and time constraints. In this study, the two diagnostic assays that targeted respectively on Mp-antibody and Mp-DNA were retrospectively investigated.

Methods

A total of 3146 children were clinically diagnosed to have CAP and were confirmed by chest X-ray during March 2015 to February 2016 in Children’s hospital of Hebei Province (China). Both of the sera and sputum samples were collected in 24 h after their admission. The Mp-antibody was examined by the passive particle agglutination assay and a fourfold or greater increase of antibody titers of paired sera or≧1:160 titer of single serum was set as the serology positive. Mp-DNA in the sputum samples was tested by a multiplex-PCR method named GeXP assay (multiplex PCR combined with automated capillary electrophoresis). In order to eliminate the false positive results caused by the asymptomatic carriage after infected by M. pneumoniae, the inconsistent samples were tested by the real-time isothermal transcription-mediated RNA amplification assay (SAT).

Results

The inter-rated agreement test was performed in 3146 CAP patients, with a highest kappa value in the school-age children as 0.783. There were 6.29% (198/3146) cases showed inconsistent results determined by GeXP and serology assay. All of the 19 GeXP(+)/Serology (−) samples and a randomly chosen 27 from 179 GeXP(−)/Serology (+) samples were tested by SAT assay, and a 97.8% diagnosis agreement was observed between SAT and GeXP assay, but not with the serology assay. In addition, patients who were detected only by serology or only by multiplex-PCR were significantly younger than those with both methods positive (3.0 and 1.5 years vs. 5.0 years, p < 0.01). The Viral-Mp coinfection accounted for 37.0% (97/262), which was more common in winter and spring (p < 0.05) and in the infantile group (p < 0.01), compared to the pure Mp positive ones.

Conclusion

In some children CAP cases, the Mp laboratory diagnosis was inconsistent between serology and multiplex-PCR assay. Verified by the SAT assay, the GeXP showed a more sensitive and reliable performance compared with the serology assay. Furthermore, employing the multiplex-PCR could provide more information on the associated pathogens for clinical assessment of CAP.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2614-3) contains supplementary material, which is available to authorized users.

Epidemiology and Molecular Characteristics of Mycoplasma pneumoniae During an Outbreak of M. pneumoniae-associated Stevens-Johnson Syndrome

BACKGROUND

An increase in Mycoplasma pneumoniae-associated Stevens-Johnson syndrome (SJS) cases at a Colorado pediatric hospital led to an outbreak investigation. We describe the epidemiologic and molecular characteristics of M. pneumoniae among SJS case-patients and surrounding community members during the outbreak.

METHODS

M. pneumoniae polymerase chain reaction-positive respiratory specimens from 5 Colorado hospitals and 4 referral laboratories underwent confirmatory polymerase chain reaction testing; positive specimens then underwent multilocus variable-number tandem-repeat analysis (MLVA) and macrolide resistance testing. Three SJS-M. pneumoniae case-patient households were surveyed using a standardized questionnaire, and nasopharyngeal/oropharyngeal swabs were obtained from all consenting/assenting household contacts. International Classification of Diseases, 9th revision codes were used to identify pneumonia cases among Colorado patients 5-21 years of age from January 2009 to March 2014.

RESULTS

Three different M. pneumoniae MLVA types were identified among the 5 SJS case-patients with confirmed infection; MLVA type 3-X-6-2 was seen more commonly in SJS case-patients (60%) than in 69 non-SJS community specimens (29%). Macrolide resistance was identified in 7% of community specimens but not among SJS case-patients. Of 15 household contacts, 5 (33%) were M. pneumoniae positive; all MLVA types were identical to those of the corresponding SJS case-patient, although the specimen from 1 contact was macrolide resistant. Overall pneumonia cases as well as those caused by M. pneumoniae specifically peaked in October 2013, coinciding with the SJS outbreak.

CONCLUSIONS

The outbreak of M. pneumoniae-associated SJS may have been associated with a community outbreak of M. pneumoniae; clinicians should be aware of the M. pneumoniae-SJS relationship. Household transmission of M. pneumoniae was common within the households investigated.

Atypical Pneumonia: Updates on Legionella, Chlamydophila, and Mycoplasma Pneumonia

Community-acquired pneumonia (CAP) has multiple causes and is associated with illness that requires admission to the hospital and mortality. The causes of atypical CAP include Legionella species, Chlamydophila, and Mycoplasma. Atypical CAP remains a diagnostic challenge and, therefore, likely is undertreated. This article reviews the advancements in the evaluation and treatment of patients and discusses current conflicts and controversies of atypical CAP.

The role of the NxTAG® respiratory pathogen panel assay and other multiplex platforms in clinical practice

INTRODUCTION

The advent of nucleic acid amplification tests has significantly improved the aetiologic diagnosis of respiratory infections. However, multiplex real-time polymerase chain reaction (PCR) can be technologically challenging. Areas covered: This paper reports the results of the main published studies on the NxTAG Respiratory Pathogen Panel (RPP) and discusses the advantages and disadvantages of extensive use of multiplex assays in clinical practice. Expert commentary: Currently available data seem to indicate that routine use of multiplex assays, including NxTAG RPP Assay, should be recommended only when epidemiological data concerning circulation of viruses and bacteria have to be collected. Their use in clinical practice seems debatable. They have limited sensitivity and specificity at least in the identification of some infectious agents or, as in the case of NxTAG RPP, they have not been evaluated in a sufficient number of patients to allow definitive conclusions. In the future, the clinical relevance of multiplex assays, including NxTAG RPP, could significantly increase, mainly because a number of new antiviral agents effective against several respiratory viruses for which no drug is presently available will be marketed. In addition, it is highly likely that the efficiency of multiplex assays will be significantly improved.

Prevalence of Atypical Pathogens in Patients With Cough and Community-Acquired Pneumonia: A Meta-Analysis

PURPOSE

Community-acquired pneumonia (CAP), acute cough, bronchitis, and lower respiratory tract infections (LRTI) are often caused by infections with viruses or Streptococcus pneumoniae. The prevalence of atypical pathogens Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and Bordetella pertussis among patients with these illnesses in the ambulatory setting has not been previously summarized. We set out to derive prevalence information from the existing literature.

METHODS

We performed a systematic review of MEDLINE for prospective, consecutive-series studies reporting the prevalence of M pneumoniae, C pneumoniae, L pneumophila and/or B pertussis in outpatients with cough, acute bronchitis, LRTI, or CAP. Articles were independently reviewed by 2 authors for inclusion and abstraction of data; discrepancies were resolved by consensus discussion. A meta-analysis was performed on each pathogen to calculate the pooled prevalence estimates using a random effects model of raw proportions.

RESULTS

Fifty studies met our inclusion criteria. While calculated heterogeneity was high, most studies reported prevalence for each pathogen within a fairly narrow range. In patients with CAP, the overall prevalences of M pneumoniae and C pneumoniae were 10.1% (95% CI, 7.1%-13.1%) and 3.5% (95% CI, 2.2%-4.9%), respectively. Consistent with previous reports, M pneumoniae prevalence peaked in roughly 6-year intervals. Overall prevalence of L pneumophila was 2.7% (95% CI, 2.0%-3.4%), but the organism was rare in children, with only 1 case in 1,765. In patients with prolonged cough in primary care, the prevalence of B pertussis was 12.4% (95% CI, 4.9%-19.8%), although it was higher in studies that included only children (17.6%; 95% CI, 3.4%-31.8%).

CONCLUSIONS

Atypical bacterial pathogens are relatively common causes of lower respiratory diseases, including cough, bronchitis, and CAP. Where surveillance data were available, we found higher prevalences in studies where all patients are tested for these pathogens. It is likely that these conditions are underreported, underdiagnosed, and undertreated in current clinical practice.

Simkania negevensis, an insight into the biology and clinical importance of a novel member of the Chlamydiales order

Simkania negevensis is a Chlamydia-related bacterium discovered in 1993 and represents the founding member of the Simkaniaceae family within the Chlamydiales order. As other Chlamydiales, it is an obligate intracellular bacterium characterized by a biphasic developmental cycle. Its similarities with the pathogenic Chlamydia trachomatis and Chlamydia pneumoniae make it an interesting bacterium. So far, little is known about its biology, but S. negevensis harbors various microbiological characteristics of interest, including a strong association of the Simkania-containing vacuole with the ER and the presence of an intron in the 23S rRNA encoding gene. Evidence of human exposition has been reported worldwide. However, there is a lack of robust clinical studies evaluating its implication in human diseases; current data suggest an association with pneumonia and bronchiolitis making S. negevensis a potential emerging pathogen. Owing to its fastidious growth requirements, the clinical relevance of S. negevensis is probably underestimated. In this review, we summarize the current knowledge on S. negevensis and explore future research challenges.

Increased prevalence of Mycoplasma pneumoniae serological positivity in Chilean young children

BACKGROUND

Mycoplasma pneumoniae is a frequent cause of respiratory infections in school children and adolescents. Epidemiological suspicion is important, since there are no specific symptoms or signs to help in diagnosing infection caused by this agent.

OBJECTIVE

To determine the variation in prevalence over the last 10 years of M. pneumoniae IgM seropositivity according to age, particularly in pre-schoolers.

METHOD

The results of M. pneumoniae IgM serological testing between January 2004 and December 2013 were analysed. Variables such as gender and month and year of sample processing were studied according to age groups (<5, 5-18, 19-50, 51-70 and >70 years of age).

RESULTS

Of a total of 20,020 serological samples, 31.9% proved positive for M. pneumoniae. All age groups showed increases in percentage seropositivity over the last 10 years, although the most significant increase corresponded to the 5-18 years group (from 15.8% to 54%), followed by children <5 years of age (from 8.6% to 30%). Seropositivity was significantly higher in women in all age groups, except in those over 50 years of age.

CONCLUSION

Children under five years of age were the group with the second highest increase in seropositivity.

Partial comparison of the NxTAG Respiratory Pathogen Panel Assay with the Luminex xTAG Respiratory Panel Fast Assay V2 and singleplex real-time polymerase chain reaction for detection of respiratory pathogens

In this study, 185 nasopharyngeal swabs were tested to compare the sensitivity and specificity of the Luminex NxTAG (NxTAG) Respiratory Pathogen Panel (RPP) Assay with those of the Luminex Respiratory Virus Panel (RVP) Fast Assay v2 and singleplex real-time polymerase chain reaction (PCR). The NxTAG Assay identified at least one infectious agent in 164 (88.7%) of the swabs. In 91 (6.2%) tests with negative results with the RVP Fast Assay v2, a virus was identified by the NxTAG (P < 0.001). With the NxTAG Assay, the detection rates were significantly higher for respiratory syncytial virus (P = 0.003), human metapneumovirus (P < 0.001), human rhinovirus/human enterovirus (P = 0.009) and human adenovirus (P < 0.001). Finally, the NxTAG Assay identified M. pneumoniae in 32 of 44 (72.7%) PCR-positive samples. However, the concordance with real-time PCR results was low for both assays. In conclusion, the results indicate that the NxTAG Assay overcomes some of the limitations of previous Luminex assays, although further studies are needed for a more complete evaluation of the new assay.

•

NxTAG Respiratory Pathogen Panel Assay was developed to improve viral detection and to simultaneously identify atypical bacteria.

•

NxTAG Assay has overcome some of the limitations of the previous Luminex assays.

•

NxTAG Assay remains generally less sensitive and specific than singleplex real-time polymerase chain reaction.

•

Further studies on more samples collected during the whole year are needed for a complete evaluation of the NxTAG Assay.

Decompressive Laminectomy Complicated by Postoperative Mycoplasma hominis Epidural Abscess and Meningitis in a Young Woman: A Case Report

CASE

A twenty-eight-year-old woman underwent decompressive laminectomy and placement of an interlaminar stabilizer due to L4/L5 disc herniation. Thirteen days later she developed a fever unresponsive to meropenem and vancomycin, along with signs of meningitis. A Mycoplasma hominis epidural abscess was identified. She had no preoperative risk factors for extragenital M. hominis infection, but had had a urinary catheter inserted intraoperatively.

CONCLUSION

M. hominis postoperative surgical site infection is a rarely identified complication of spinal surgery. Seeding from the genitourinary tract is the most likely source.

Is There any Relationship Between Extra-Pulmonary Manifestations of Mycoplasma Pneumoniae Infection and Atopy/Respiratory Allergy in Children?

Mycoplasma pneumoniae is a common cause of respiratory infections in children, but sometimes extra-pulmonary diseases can be observed. The immunological mechanisms involved in these extra-respiratory complications are unknown. Here, we report a small case series of Mycoplasma-related diseases including 5 children who developed: i) aseptic meningitis; ii) urticarial rash and pericardial effusion; iii) pleural effusion with severe eosinophilia; iv) Stevens-Johnson syndrome; v) multiform erythema. Interestingly, all children were moderately to highly atopic, as a common immunologic feature.

Epidemiology and clinical features of segmental/lobar pattern Mycoplasma pneumoniae pneumonia: A ten-year retrospective clinical study

Mycoplasma pneumoniae plays an important role in community-acquired pneumonia. However, epidemiological and clinical studies on the segmental/lobar pattern (S/L) radiographic-pathologic subtype of pediatric Mycoplasma pneumoniae pneumonia (MPP) are rare. The current study retrospectively analyzed the epidemiological and clinical characteristics of pediatric MPP patients. A total of 1,933 children with MPP received treatment at a single hospital between 2000 and 2009, of which 684 (35.4%) were diagnosed with S/L-MPP. The annual incidence of S/L-MPP in children with MPP increased throughout the duration of this study (from 6.4 to 59.6%, P<0.001), which was particularly evident after 2003. S/L-MPP was predominantly found in pre-school-aged children (4-6 years old; 56.6%). Compared with non-S/L-MPP, S/L-MPP was more closely associated with severe manifestations, including higher rates of fever (90.2 vs. 83.3%), pleural effusion (3.9 vs. 1.3%), extrapulmonary manifestations (26.2 vs. 21.2%), abnormal white blood cell counts (65.5 vs. 55.2%), abnormal C-reactive protein levels (30.9 vs. 23.7%) and bacterial co-infection (32.0 vs. 24.9%), as well as longer durations of fever (4.13±4.28 vs. 3.02±2.22 days) and hospitalization (12.70±4.54 vs. 9.22±5.12 days). Older S/L-MPP patients showed higher rates and longer durations of fever and cough; however, they also displayed a lower rate of extrapulmonary manifestations when compared with younger patients. In conclusion, the annual incidence of S/L-MPP has increased in recent years. Pre-school-aged children (4-6 years) with MPP are more likely to display a segmental/lobar pattern, which is associated with more severe clinical manifestations than other MPP infection patterns.

Antibiotics for community-acquired lower respiratory tract infections secondary to Mycoplasma pneumoniae in children

Background. Mycoplasma pneumoniae (M. pneumoniae) is widely recognised as an important cause of community-acquired lower respiratory tract infection (LRTI) in children. Pulmonary manifestations are typically tracheobronchitis or pneumonia but M. pneumoniae is also implicated in wheezing episodes in both asthmatic and non-asthmatic individuals. Although antibiotics are used to treat LRTIs, are view of several major textbooks offers conflicting advice for using antibiotics in the management of M. pneumoniae LRTI in children.Objectives To determine whether antibiotics are effective in the treatment of childhood LRTI secondary to M. pneumoniae infections acquired in the community.Search methods We searched CENTRAL (2014, Issue 3), MEDLINE (1966 to July week 4, 2014), EMBASE (1980 to July, 2014), and both WHOICTRP and ClinicalTrials.gov (13 August 2014).Selection criteria Randomised controlled trials (RCTs) comparing antibiotics commonly used for treating M. pneumoniae (i.e. macrolide, tetracycline or quinolone classes) versus placebo, or antibiotics from any other class in the treatment of children under 18 years of age with community acquired LRTI secondary to M. pneumoniae.Data collection and analysis The review authors independently selected trials for inclusion and assessed methodological quality. We extracted and analysed relevant data separately and resolved disagreements by consensus.Main results A total of 1912 children were enrolled from seven studies. Data interpretation was limited by the inability to extract data that referred to children with M. pneumoniae. In most studies, clinical response did not differ between children randomised to a macrolide antibiotic and children randomised to a non-macrolide antibiotic. In one controlled study (of children with recurrent respiratory infections, whose acute LRTI was associated with Mycoplasma, Chlamydia or both, by polymerase chain reaction and/or paired sera) 100% of children treated with azithromycin had clinical resolution of their illness compared to 77% not treated with azithromycin at one month. Authors' conclusions There is insufficient evidence to draw any specific conclusions about the efficacy of antibiotics for this condition in children (although one trial suggests macrolides may be efficacious in some children with LRTI secondary to Mycoplasma). The use of antibiotics has to be balanced with possible adverse events. There is still a need for high quality, double-blinded RCTs to assess the efficacy and safety of antibiotics for LRTI secondary to M. pneumoniae in children.

First report on prevalence and risk factors of severe atypical pneumonia in Vietnamese children aged 1-15 years

Background

Atypical pathogens such as Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila are increasingly recognized as important causes of community acquired pneumonia (CAP) worldwide. Such etiological data for Vietnam is scarce and clinical doctors lack accurate information on which to base their diagnosis and treatment of pneumonia. This study identifies the prevalence and risk factors of severe community acquired pneumonia due to these atypical pathogens (severe-ApCAP) in children aged 1–15 years with CAP in a pediatric hospital in Hanoi, Vietnam.

Methods

722 hospitalized children with CAP were recruited for detecting those atypical pathogens, using multiplex PCR and ELISA. Clinical and epidemiological data were collected. Multivariate logistic-regression analyses were performed to evaluate the associations of potential risk factors with severe-ApCAP.

Results

Among 215 atypical pathogen-positive CAP cases, 45.12% (97/215) were severe-ApCAP. Among the severe-ApCAP group, 55.67% (54/97) cases were caused by pure atypical pathogens and 44.33% (43/97) resulted from a co-infection with typical respiratory pathogens. M. pneumoniae was the most common, with 86.6% cases (84/97) in the severe-ApCAP group, whereas C. pneumoniae and L. pneumophila were less frequent (6.19% and 7.22%, respectively). The highest rate of severe-ApCAP was in children younger than two years (65.98%). The differences related to age are statistically significant (P = 0.008).

The factors significantly associated with severe-ApCAP were age (OR = 0.84, 95% CI = 0.75-0.93, P = 0.001), co-infection with typical bacteria (OR = 4.86, 95% CI = 2.17-10.9, P < 0.0001), co-infection with respiratory viruses (OR = 4.36, 95% CI = 1.46-13.0, P = 0.008), respiratory/cardiac system malformation (OR = 14.8, 95% CI = 1.12 -196, P = 0.041) and neonatal pneumonia (OR = 11.1, 95% CI = 1.06 -116, P = 0.044).

Conclusions

Severe-ApCAP presented at a significant rate in Vietnamese children. More than 50% of severe-ApCAP cases were associated with pure atypical pathogen infection. M. pneumoniae appeared most frequently. The highest rate of severe-ApCAP was in children younger than two years. Younger age and co-infection with typical bacteria or viruses were the most significant risk factors, while respiratory/cardiac system malformation and neonatal pneumonia were additional potential risk factors, associated with severe-ApCAP in Vietnamese children.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-1304) contains supplementary material, which is available to authorized users.

[Value of routine identification of respiratory infectious agents in children hospitalized with an acute asthma exacerbation]

Introduction

Chez l’enfant les exacerbations d’asthme sont le plus souvent déclenchées par une infection respiratoire. L’objectif de cette étude était d’évaluer l’intérêt de l’identification des pathogènes respiratoires chez les enfants hospitalisés pour une exacerbation d’asthme.

Patients et méthodes

Il s’agit d’une étude rétrospective incluant tout enfant hospitalisé pour une exacerbation d’asthme dans notre unité entre janvier 2010 et décembre 2011 et analysant la prescription des examens microbiologiques, leurs indications, leur rendement, leur impact sur la prise en charge médicale et leur coût.

Résultats

Cent quatre-vingt-dix-sept enfants ont été inclus. Une recherche d’agent pathogène respiratoire avait été réalisée chez 157 enfants (79,7 %), surtout en cas d’infection oto-rhino-laryngologique (ORL), d’hypoxémie ou de pneumonie. Un virus avait été identifié chez 30 (23,8 %) des 126 enfants prélevés. Les analyses bactériologiques avaient eu un rendement faible puisque seulement 3,2 % des analyses par amplification génique (PCR) pour Mycoplasma pneumoniae avaient été positives (n = 4/125). Aucune autre bactérie n’avait été identifiée. Aucun lien n’a pu être établi entre les résultats microbiologiques et la gravité de l’exacerbation. La prise en charge thérapeutique avait été peu modifiée par ces résultats. Le coût global avait été de plus de 40 400 euros pour les 2 ans d’étude.

Conclusion

D’après nos résultats la recherche de pathogènes respiratoires au cours des exacerbations d’asthme a un intérêt modéré en dehors de l’aspect épidémiologique. L’impact du rhinovirus, du coronavirus, du bocavirus et de l’entérovirus, non recherchés en routine hospitalière, reste cependant à préciser.

Oligohydramnios increases the risk of respiratory hospitalization in childhood: a population-based study

BACKGROUND

Pulmonary hypoplasia is associated with reduced lung function in infancy. The aim of this study was to evaluate the hypothesis that children exposed to oligohydramnios display an increased risk of hospitalization for respiratory illness by using a population-based matched-cohort design.

METHODS

We used three nationwide population-based data sets to identify 5,228 women who gave birth during 2004 to 2007 and were diagnosed with oligohydramnios during the third trimester of pregnancy. A cohort of 20,912 unaffected pregnant women was matched with these cases, according to neonatal sex and gestational age, maternal age and education, and level of prenatal care. Respiratory hospitalization and respiratory failure were defined using discharge diagnostic codes.

RESULTS

Oligohydramnios-exposed children had an 8% higher incidence rate of respiratory hospitalization and an 80% higher incidence rate of respiratory failure, compared with children without oligohydramnios exposure. This risk remained after adjusting for all potential risk factors. Cox regression analyses indicated that the adjusted hazard ratios of respiratory hospitalization and respiratory failure were 1.07 (95% confidence interval (CI): 1.01-1.15; P = 0.030) and 2.20 (95% CI: 1.26-3.84; P = 0.005), respectively.

CONCLUSION

Children exposed to oligohydramnios during the third trimester of pregnancy display an increased risk of hospitalization for respiratory illness.

Comparative effectiveness of ceftriaxone in combination with a macrolide compared with ceftriaxone alone for pediatric patients hospitalized with community-acquired pneumonia

BACKGROUND

Guidelines for management of community-acquired pneumonia recommend empiric therapy with a macrolide and beta-lactam when infection with Mycoplasma pneumoniae is a significant consideration. Evidence to support this recommendation is limited. We sought to determine the effectiveness of ceftriaxone alone compared with ceftriaxone combined with a macrolide with respect to length of stay and total hospital costs.

METHODS

We conducted a retrospective cohort study of children 1-17 years with pneumonia, using Poisson regression and propensity score analyses to assess associations between antibiotic and length of stay. Multivariable linear regression and propensity score analyses were used to assess log-treatment costs, adjusting for patient and hospital characteristics and initial tests and therapies.

RESULTS

A total of 4701 children received combination therapy and 8892 received ceftriaxone alone. Among children 1-4 years of age, adjusted models revealed no significant difference in length of stay, with significantly higher costs in the combination therapy group [cost ratio: 1.08 (95% confidence interval: 1.05-1.11)]. Among children 5-17 years of age, children receiving combination therapy had a shorter length of stay [relative risk: 0.95 (95% confidence interval: 0.92-0.98)], with no significant difference in costs [cost ratio: 1.01 (95% confidence interval: 0.98-1.04)].

CONCLUSIONS

Combination therapy did not appear to benefit preschool children but was associated with higher costs. Among school-aged children, combination therapy was associated with a shorter length of stay without a significant impact on cost. Development of sensitive point-of-care diagnostic tests to identify children with M. pneumoniae infection may allow for more focused prescription of macrolides and enable comparative effectiveness studies of targeted provision of combination therapy.

Pharmacological approach to wheezing in preschool children

INTRODUCTION

Wheezing disorders are very common during childhood (particularly among preschool children), and represent a significant burden for patients, their families, the healthcare system, and society as a whole. Identifying wheezing phenotypes, and recognizing the risk factors associated with each, may help to predict long-term outcomes, distinguish high-risk children who may benefit from secondary prevention measures, and ensure that the most effective therapy is prescribed for each case.

AREAS COVERED

The main aim of this review is to analyze the characteristics of the drugs currently used to treat wheezing in preschool children, and discuss the results obtained in children with different wheezing phenotypes.

EXPERT OPINION

The continuous or intermittent administration of various oral or inhaled drugs could theoretically be effective in preventing or controlling wheezing in preschool children. However, the optimal management of acute preschool wheezing episodes has not yet been determined mainly because of their phenotypical heterogeneity.

International guidelines on tackling community-acquired pneumonia show major discrepancies between developed and developing countries

AIM

The goal of this study was to compare the current guidelines on diagnosis and treatment of paediatric community-acquired pneumonia (CAP) in developing and developed countries.

METHODS

A literature search was performed consulting the Medline, Embase, Current Contents, National Guideline Clearinghouse and Cochrane database, from January 2000 to March 2013.

RESULTS

Twelve guidelines were selected: six from developed countries and six from developing countries. Major discrepancies between the diagnosis and treatment approaches recommended by guidelines covering developing and developed countries were revealed. The search also highlighted differences between recommendations issued in similar settings.

CONCLUSION

The guidelines show wide variations and weak recommendations and further research is needed to improve clinical outcomes and make better use of resources.

Ιnflammatory or septic arthritis associated with mycoplasma pneumonia in children: Two case reports and review of the literature

Inflammatory or septic arthritis due to Mp is an extremely unusual manifestation in children, and the functional outcome of the joints is difficult to be predicted. Two cases with Mp infection are presented. The first patient had positive PCR for Mp after hip aspiration and arthrotomy with thorough irrigation and debridement. A flattened femoral head was detected during the follow-up, which became quite spherical a year after. An arthrotomy with medial synovectomy of the knee was performed in the second patient. Lack of full knee extension was presented during the first 3 months, which gradually decreased to 7° in the final follow-up. The suspicion of Mp infection with extra-pulmonary involvement in children is mainly based on clinical, epidemiological and radiological data, but laboratory testing is required for confirmation. Rapid diagnosis of probability consists of serum tests, and their results are essential for early therapeutic planning. The direct diagnosis of Mp DNA through polymerase chain reaction (PCR) provides specificity and sensitivity. Very few cases of arthritis associated with Mp infection have been published but not with the severity of our cases. Clinical suspicion of Mp infection is of great importance, and the outcome depends on early diagnosis and specific treatment.

Macrolide-resistant Mycoplasma pneumoniae: its role in respiratory infection

Although the clinical relevance of antibiotic treatment in influencing the natural course of Mycoplasma pneumoniae-associated respiratory diseases is questioned by some physicians, most experts suggest that antibiotics should be systematically used in patients with M. pneumoniae respiratory infections, especially those involving the lower respiratory tract. Macrolides (MLs), tetracyclines (TCs) and fluoroquinolones (FQs) are the drugs of choice for M. pneumoniae infection, but only MLs are recommended for children. The main aim of this review is to analyse what is known about M. pneumoniae resistance to MLs and discuss the most reasonable approach to treating patients with M. pneumoniae infection at a time when resistant strains are being increasingly detected. The results show that no change in ML prescription is needed in countries in which the incidence of ML-resistant M. pneumoniae is low; however, in countries in which ML-resistant M. pneumoniae strains are very common, the replacement of an ML by a TC or FQ should be considered depending on the severity of the disease. A number of cases treated with ineffective antibiotics have shown similar outcomes to those observed in patients infected by susceptible strains. This seems to indicate that there is no need to change ML use systematically in the case of mild to moderate disease, but other antibiotics should be prescribed if the symptoms persist or there are signs of a clinical deterioration.

Antibiotics for community-acquired lower respiratory tract infections secondary to Mycoplasma pneumoniae in children

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae) is widely recognised as an important cause of community-acquired lower respiratory tract infection (LRTI) in children. Pulmonary manifestations are typically tracheobronchitis or pneumonia but M. pneumoniae is also implicated in wheezing episodes in both asthmatic and non-asthmatic individuals. Although antibiotics are used to treat LRTIs, a review of several major textbooks offers conflicting advice for using antibiotics in the management of M. pneumoniae LRTI in children.

OBJECTIVES

To determine whether antibiotics are effective in the treatment of childhood LRTI secondary to M. pneumoniae infections acquired in the community.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 2), which contains the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (1966 to February week 5, 2012) and EMBASE (1980 to March 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing antibiotics commonly used for treating M. pneumoniae (i.e. macrolide, tetracycline or quinolone classes) versus placebo, or antibiotics from any other class in the treatment of children under 18 years of age with community-acquired LRTI secondary to M. pneumoniae.

DATA COLLECTION AND ANALYSIS

The review authors independently selected trials for inclusion and assessed methodological quality. We extracted and analysed relevant data separately. We resolved disagreements by consensus.

MAIN RESULTS

A total of 1912 children were enrolled from seven studies. Data interpretation was limited by the inability to extract data that referred to children with M. pneumoniae. In most studies, clinical response did not differ between children randomised to a macrolide antibiotic and children randomised to a non-macrolide antibiotic. In one controlled study (of children with recurrent respiratory infections, whose acute LRTI was associated with Mycoplasma, Chlamydia or both by polymerase chain reaction, and/or paired sera) 100% of children treated with azithromycin had clinical resolution of their illness compared to 77% not treated with azithromycin at one month.

AUTHORS' CONCLUSIONS

There is insufficient evidence to draw any specific conclusions about the efficacy of antibiotics for this condition in children (although one trial suggests macrolides may be efficacious in some children with LRTI secondary to Mycoplasma). The use of antibiotics has to be balanced with possible adverse events. There is still a need for high quality, double-blinded RCTs to assess the efficacy and safety of antibiotics for LRTI secondary to M. pneumoniae in children.

Antibiotic therapy for pediatric community-acquired pneumonia: do we know when, what and for how long to treat?

Community-acquired pneumonia (CAP) is a common cause of morbidity among children in developed countries and accounts for an incidence of 10-40 cases per 1000 children in the first 5 years of life. Given the clinical, social and economic importance of CAP, there is general agreement that prompt and adequate therapy is essential to reduce the impact of the disease. The aim of this discussion paper is to consider critically the available data concerning the treatment of uncomplicated pediatric CAP and to consider when, how and for how long it should be treated. This review has identified the various reasons that make it difficult to establish a rational approach to the treatment of pediatric CAP, including the definition of CAP, the absence of a pediatric CAP severity score, the difficulty of identifying the etiology, limited pharmacokinetic (PK)/pharmacodynamic (PD) studies, the high resistance of the most frequent respiratory pathogens to the most widely used anti-infectious agents and the lack of information concerning the changes in CAP epidemiology following the introduction of new vaccines against respiratory pathogens. More research is clearly required in various areas, such as the etiology of CAP and the reasons for its complications, the better definition of first- and second-line antibiotic therapies (including the doses and duration of parenteral and oral antibiotic treatment), the role of antiviral treatment and on how to follow-up patients with CAP. Finally, further efforts are needed to increase vaccination coverage against respiratory pathogens and to conduct prospective studies of their impact.