Diagnosis of Mycoplasma pneumoniae pneumonia in children

Laboratory diagnosis and treatment of Mycoplasma pneumoniae infection in children: a review

Mycoplasma pneumoniae (MP) is the cause of Mycoplasma pneumoniae pneumonia (MPP) in children and adolescents, with the clinical manifestations highlighted by intermittent irritating cough, accompanied by headache, fever and muscle pain. This paper aimed to study the research status and focal points in MP infection, especially the common laboratory diagnostic methods and clinical treatment of Mycoplasma pneumoniae. Laboratory diagnostic methods include molecular assay, serological antibody detection, rapid antigen detection and isolation and culture. Polymerase chain reaction (PCR) is the gold standard with high sensitivity and specificity. The serological antibody can detect various immune antibodies qualitatively or quantitatively in serum. Rapid antigen can be detected faster, with no equipment environment requirements, which can be used for the early diagnosis of MP infection. While the culture growth cycle is long and insensitive, not recommended for routine diagnosis. Macrolides were the preferred drug for children with MPP, while the drug resistance rate was rising in China. Tetracycline can be substituted but was not recommended for children under 8 years of age, quinolone drugs are not necessary, severe MPP can be combined with glucocorticoids, involving the nervous or immune system can choose gamma globulin. Other treatments for MPP including symptomatic treatment which can alleviate symptoms, improve lung function and improve prognosis. A safe and effective vaccine needed to be developed which can provide protective immunity to children and will reduce the incidence of MPP.

Age-related effects of Mycoplasma pneumoniae infection and subsequent asthma exacerbation in children

BACKGROUND

Mycoplasma pneumoniae causes community-acquired pneumonia in children and increases asthma risk, but large studies are lacking.

OBJECTIVE

To assess the link between M. pneumoniae infection and to asthma exacerbation, in children with allergies, and age of infection impact.

METHODS

This retrospective cohort study analyzed medical records of South Korean children between January 2002 and December 2017. The study's exposure was hospitalization with an M. pneumoniae-related diagnosis, and the outcome was defined as asthma exacerbation, confirmed by hospitalization at least 6 months after M. pneumoniae infection, with alternative validation using asthma diagnosis and systemic steroid prescription records. Hazard ratios (HRs) for asthma exacerbation risk were estimated for the matched cohort using a Cox proportional hazards model stratified by allergic comorbidities. Time-dependent covariates and age-stratified exposure groups were used to calculate odds ratios.

RESULTS

The study included 84,074 children with M. pneumoniae infection and 336,296 unexposed children. Follow-up for 12.2 ± 2.3 years found the exposed group had a significant risk of asthma exacerbation (HR 2.86, 95% confidence interval [CI] 2.67-3.06) regardless of allergic comorbidities. The risk was highest (over threefold) in children infected between 24 and 71 months. Sensitivity analysis using an alternative definition of the outcome showed an HR of 1.38 (95% CI 1.35-1.42), further supporting the association between M. pneumoniae infection and asthma exacerbation.

CONCLUSION

M. pneumoniae infection was significantly associated with an increased risk of subsequent asthma exacerbation regardless of allergic comorbidities. Further research needed for understanding and confirmation.

Cavitatory necrotising pneumonia with extrapulmonary multi-systemic involvement — a rare presentation of macrolide-resistant Mycoplasma pneumoniae

Background

Mycoplasma pneumoniae is one of the leading causes of community-acquired pneumonia. Due to its microbiological variation, clinical presentations of mycoplasma infections are atypical and diverse. Multiple pulmonary and extrapulmonary manifestations of Mycoplasma pneumoniae have been documented. Among pulmonary, common manifestations are fever, malaise, lymphadenopathy, pneumonia, upper respiratory tract infections, sinusitis, etc. Necrotising pneumonia leading to cavitation as a manifestation is rather an uncommon presentation.

Case presentation

We are reporting a rare case of a 5-year-old female child who presented with bilateral haemorrhagic pleural effusion and necrotising pneumonia with cavitation along with extrapulmonary manifestation in the form of maculo-papular rash, Coombs-positive haemolytic anaemia and serositis. The child was started on azithromycin and symptomatic management, but she did not respond to it; she had clinical worsening and evidence of radiological necrotising pneumonia. The child was treated as macrolide-resistant mycoplasma pneumonia with levofloxacin, steroids and rigorous physiotherapy.

Conclusions

Accurate clinical acumen along with timely radiological imaging is the need of the hour for early diagnosis of macrolide-resistant mycoplasma pneumonia (MRMP). This case also emphasises role of fluoroquinolones and steroids in treatment of macrolide-resistant mycoplasma pneumonia.

Mycoplasma pneumoniae IgG positivity is associated with tic severity in chronic tic disorders

Infectious pathogens may represent an environmental risk factor for chronic tic disorders (CTD). This cross-sectional study aimed to determine whether Mycoplasma pneumoniae (M. pneumoniae) IgG positivity is associated with the presence or severity of tics. We compared M. pneumoniae IgG positivity across three groups: children and adolescents (3-16 years) with CTD (CTD group; n = 302); siblings (3-10 years) of people with CTD who developed tics within a seven-year follow-up period (tic onset group; n = 51); siblings (4-10 years) who did not develop tics within the study period and were ≥10-years-old at their last assessment (unaffected group; n = 88). The relationship between M. pneumoniae IgG positivity and the presence and severity of tics was analysed using multilevel models controlling for site, family relatedness, sex, age, presence of comorbid obsessive-compulsive and/or attention-deficit/hyperactivity disorder and use of psychotropic medication. M. pneumoniae IgG positivity was not associated with the presence of CTD, or the first onset of tics as compared to siblings who remained unaffected. M. pneumoniae IgG positivity was associated with a higher tic severity score within the CTD group (β = 2.64, s.e. = 1.15, p = 0.02). It is possible that M. pneumoniae infection influences tic severity in CTD or, that having more severe tics, increases the risk of infection. However, it is more likely that the association observed in this study reflects a propensity toward enhanced immune responses in people with CTD and that, rather than a causal relationship, infection and greater tic severity are indirectly linked via shared underlying immune mechanisms.

Pediatric Non-COVID-19 Community-Acquired Pneumonia in COVID-19 Pandemic

Introduction

The COVID-19 lockdown strategies were associated with a significant decrease in infectious diseases disseminated through airborne or fecal–oral transmissions. Social distancing and other lockdown strategies effectively slowed down the spread of common respiratory viral diseases and decreased the need for hospitalization among children. Thus, a decline in the incidence of respiratory viral diseases had been reported following the COVID-19 outbreak. However, the trend of non-COVID-19 pneumonia in children remains uncertain. This study aimed to assess the impact of the COVID-19 pandemic on the incidence of non-COVID-19 community-acquired pneumonia in children.

Materials and Methods

We conducted a retrospective analysis of all patients (age ≤18 years) presenting with pulmonary infection from January 2019 to December 2020 in a tertiary-level teaching hospital. We compared the number of pediatric patients admitted to our hospital with community-acquired pneumonia from January to December 2020 to those from the same period in 2019.

Results

A total of 65 patients were diagnosed with community-acquired pneumonia in 2019 and 18 in 2020. The number of patients with community-acquired pneumonia in 2020 was lower than that in 2019 by 47 cases in 2020. The most age distribution of pediatric patients with community-acquired pneumonia was 2–5 years in 2019, indicating the decreasing number of community-acquired pneumonia patients from 36 patients in 2019 to 3 in 2020.

Conclusion

The number of pediatric with community-acquired pneumonia was lower than in the same period in 2019, which markedly decreased (−72.3%) in 2020. These interventions applied to control the COVID-19 pandemic were effective not only in substantial changes in the seasonal influenza activity but also in decreasing cases of pediatric community-acquired pneumonia.

Effects of four types of chinese medicines as concomitant drugs with azithromycin for the treatment of mycoplasma pneumonia in children in China: a network meta-analysis

OBJECTIVE

The purpose of this study was to evaluate the efficacy of the use of four concomitant Chinese medicines with azithromycin in the treatment of mycoplasma pneumonia in children (MPC) by using network meta-analysis (NMA) and ranking them according to their performances.

METHODS

There were a total of 130 randomly controlled trials of four different concomitant Chinese medicines with azithromycin for the treatment of MPC in many databases, and an NMA was conducted in them by using Stata (version 13.0) software to evaluate the odds ratio (OR) and sequence of the different combinations. The included studies were divided into two groups: control group (azithromycin alone) and observation group (one of four azithromycin combinations).

RESULTS

A total of 13119 cases were included in this study, and the results showed that the pooled OR and 95% confidence interval (CI) of MPC improvement compared with azithromycin alone were 4.76 (3.18-7.14) for azithromycin and Reduning, 5.66 (4.50-7.12) for azithromycin and Tanreqing, 4.84 (3.35-7.01) for azithromycin and Xiyanping, and 4.58 (3.59-5.83) for azithromycin and Yanhuning, respectively. This study shows the significant efficacy of Chinese concomitant drug. The combination of azithromycin with Tanreqing is the best candidate of concomitant drug in terms of clinical efficacy. Its surface under the cumulative ranking (SUCRA) score was 85.5, while the SUCRA score for the azithromycin and Yanhuning combination was the worst, which is 48.4.

CONCLUSIONS

The combination of azithromycin with Tanreqing is the most promising group among four combinations for the treatment of MPC.

Serological and molecular detection of Mycoplasma pneumoniae in children with community-acquired lower respiratory tract infections

This study was designed to evaluate the incidence of Mycoplasma pneumoniae infection in children with community-acquired lower respiratory tract infections (LRTIs). A total of 245 patients 6 months to 12 years of age were investigated for M. pneumoniae employing serological tests, polymerase chain reaction (PCR), nested PCR, and reverse transcription PCR (RT-PCR) on throat swab samples. Forty five (59.2%) children <5 years and 31 (40.7%) children ≥5 years age group were positive for M. pneumoniae infection, and this difference was statistically significant (P ≤ 0.01).Clinical and radiological findings across M.pneumoniae-positive and -negative cases were comparable. Serology, PCR, nested PCR, and RT-PCR together detected M. pneumoniae infection in 76 (31%) patients. Sensitivity, specificity, and positive and negative predictive values of PCR were 16.18%, 95.48%, 57.89%, and 74.78%, respectively, and those of serology were 57.89%, 74.78%, 16.18%, and 95.48%, respectively. Serological and molecular detection in combination is useful for rapid and reliable diagnosis of M. pneumoniae infections in children with LRTIs.

Comparison of enzyme-linked immunosorbent assay with indirect immunofluorescence assay for the diagnosis of Mycoplasma pneumoniae infection

BACKGROUND

The study aimed to compare enzyme-linked immunosorbent assay (ELISA) with indirect immunofluorescence assay (IFA) in the diagnosis of Mycoplasma pneumoniae infection.

METHODS

From March 2016 to May 2017, 180 patients suspected with M. pneumoniae infection were enrolled. The SeroMP kit using ELISA and PNEUMOSLIDE kit using IFA were performed in parallel to detect the IgM antibodies against M. pneumoniae. Cohen's kappa statistics were used to assess the agreement between the ELISA and IFA assays, multivariate logistic regression analysis was used to evaluate risk factors for the discordance between the ELISA and IFA assays.

RESULTS

The mean age of the enrolled subjects was 46.6 ± 21.1 years. For detection of M. pneumoniae infection, the positivities of the ELISA and IFA assays were 15.6% (95% CI: 11.0%, 21.6%) and 10.0% (95% CI: 6.4%, 15.3%), respectively. The total positivity was 19.4% (95% CI: 14.3%, 25.8%). The agreement between the ELISA and IFA assays was low (κ = 0.117, P < 0.001). Variables associated with discordant results between ELISA and IFA assays in multivariate analysis were as follows: male (OR: 0.366; 95% CI: 0.149, 0.899; P < 0.05), age (>33 years old; OR: 0.313; 95% CI: 0.129, 0.758; P < 0.05).

CONCLUSION

In detection of M. pneumoniae infection, low agreement was found in IgM assays between the ELISA and IFA methods, female and younger age were significant risk factors for the discordance. A combination of ELISA and IFA tests would be recommended, in order to detect more patients suspected of M. pneumoniae infection in clinical practice.

Reversible splenial lesion syndrome associated with acute Mycoplasma pneumoniae-associated encephalitis: A report of four cases and literature review

Reversible splenial lesion syndrome (RESLES) is a rare clinico-radiological syndrome that is defined as reversible lesions that involve the splenium of the corpus callosum (SCC). RESLES has been reported in patients with a broad spectrum of diseases and conditions, including infections, hypoglycemia and poisoning. The present report described four RESLES cases triggered by Mycoplasma pneumoniae (M. pneumoniae) and discussed the associated diagnostic challenges. Four cases of acute M. pneumoniae-associated encephalitis that displayed RESLES were reviewed. The clinical presentations were nonspecific in these patients. However, magnetic resonance imaging (MRI) revealed consistent lesions in the SCC with a hyperintensity in diffusion-weighted imaging (DWI) and hypointensities in T1WI, which disappeared after a variable lapse. Treatment with azithromycin or combined treatment with immunomodulatory agents if necessary led to a good prognosis. The present findings indicated that radiological diagnosis of RESLES should be considered in patients with M. pneumoniae-associated encephalitis. Furthermore, serum Mycoplasma antibody is important for the diagnosis of M. pneumoniae-associated encephalitis.

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.

Bullous Skin Manifestations of Mycoplasma pneumoniae Infection: A Case Series

Bullous skin lesions are uncommon in children. While it is well known that Mycoplasma infections are associated with papular skin manifestations, bullous skin lesions are not commonly reported. Mycoplasma pneumoniae is a very common bacterial pathogen causing respiratory tract infection in children and adults. We report 2 children with serology-confirmed Mycoplasma infection who were hospitalized for blistering skin lesions. Both of our patients responded well to corticosteroids and one of them required intravenous immunoglobulin. The aim of this case report is to raise awareness that Mycoplasma pneumoniae infection can present with bullous skin lesions, and to briefly review the pathophysiology, diagnosis, and management of the skin manifestation of Mycoplasma infection.

A Sweet Case of Mycoplasma

Sweet syndrome, also known as acute febrile neutrophilic dermatosis, is an uncommon inflammatory disorder marked by fever and swelling of the skin that can be very painful. It is especially rare in the pediatric population. Infection is a well-known trigger for Sweet syndrome, but this entity has, to our knowledge, never been described after Mycoplasma infection. Herein, we describe the first pediatric case of febrile neutrophilic dermatosis associated with Mycoplasma infection.

Prevalence of Mycoplasma pneumoniae Infection in Malagasy Children

BACKGROUND

Childhood community-acquired pneumonia is a leading cause of childhood morbidity in low-income countries. The etiologic agents are usually Staphylococcus aureus, Streptococcus pneumoniae and Mycoplasma pneumoniae. M. pneumoniae was recognized as a cofactor in asthmatic disease. High asthma prevalence was reported in Madagascar. Our aim was to clarify the prevalence of M. pneumoniae infection in this country and its relationship with asthma.

METHODS

A prospective study was conducted in 351 children (from 2 to 16 years of age) from January 2012 to December 2014. According to the clinical symptoms, children were enrolled in 3 groups: "control group" (CG, n = 106), "asthma group" (n = 129) and "pneumonia group" (n = 116). The IgG and IgM M. pneumoniae status was evaluated by an enzyme-linked immunosorbent assay. Clinical signs of infection, socioeconomic data and antimicrobial treatment were recorded.

RESULTS

The overall prevalence of M. pneumoniae infection was 18.2%. The multivariate analysis demonstrated that M. pneumoniae infection was significantly more frequent in the CG [pneumonia group vs. CG: odds ratio = 0.45 (0.21-0.91), P = 0.037 and asthma group vs. CG: odds ratio = 0.39 (0.18-0.87), P = 0.021]. The C-reactive protein value was significantly higher in children with M. pneumonia-positive serology (85 vs. 61 mg/L, P = 0.03). Of note, 99 (41%) children received antibiotics before attending.

CONCLUSIONS

We report a prevalence of 18.2% for M. pneumoniae infection in children in Madagascar. The prevalence of M. pneumoniae infection was higher in the control patients than in asthmatic ones.

Mycoplasma Infection as a cause of Persistent Fever after Intravenous Immunoglobulin Treatment of Patients with Kawasaki Disease: Frequency and Clinical Impact

Background

Mycoplasma is a common cause of respiratory infections and may require differential diagnosis from Kawasaki disease (KD). In this study, we investigated the frequency and clinical manifestations of mycoplasma infection in patients with KD.

Materials and Methods

Medical records of 375 in-patients admitted for treatment during the acute stage of KD, were collected, and reviewed retrospectively. Of these patients, 152 (40.5%) were also tested for recent mycoplasma infection. Patients with positive results (anti-mycoplasma IgM Ab >1:640 or cold agglutinin >1:64) were designated as the case group (n = 37, 24.3%) whereas those with negative results were designated as the control group (n = 115, 75.7%). Clinical findings of the two groups were compared.

Results

Patients in the case group were older than those in the control group (mean age, 48.2 ± 32.1 months, vs. 31.7 ± 21.7 months; P = 0.001). There were significant differences between the case and control groups in the changes in the extremities (78.3% vs. 57.4%, respectively; P = 0.031), and in fever duration (6.5 ± 2.5 days vs. 5.4 ± 1.5 days; P = 0.047). Of the 37 patients with positive mycoplasma testing, 7 (18.9%) had persistent fever even after the symptoms and signs of systemic inflammation (acute phase of KD) had been resolved. These patients were positive for mycoplasma infection during further evaluation of persistent fever, and all of them responded to macrolide antibiotics.

Conclusions

We found that mycoplasma infection is somewhat related to KD. When fever persists after resolution of the acute stage of KD, mycoplasma infection may be considered as a possible cause of fever in preschool-aged children.

Role of Serum Mycoplasma pneumoniae IgA, IgM, and IgG in the Diagnosis of Mycoplasma pneumoniae-Related Pneumonia in School-Age Children and Adolescents

Mycoplasma pneumoniae is an important causative pathogen of community-acquired pneumonia in children. Rapid and reliable laboratory diagnosis of M. pneumoniae infection is important so that appropriate antibiotic treatment can be initiated to reduce the misuse of drugs and resistance rates. Anti-M. pneumoniae immunoglobulin M (IgM) is an indicator of recent primary infection but can persist for several months after initial infection. It has been suggested that anti-M. pneumoniae immunoglobulin A (IgA) can be a reliable indicator for recent M. pneumoniae infection in adults. We investigated the clinical diagnostic value of M. pneumoniae IgA in school-age children and adolescents with M. pneumoniae-related pneumonia. Eighty children with pneumonia and seropositive for M. pneumoniae IgM or with a 4-fold increase of anti-M. pneumoniae immunoglobulin G (IgG) were enrolled from May 2015 to March 2016. The titers of M. pneumoniae IgA, IgM, and IgG, the clinical features, and laboratory examinations of blood, C-reactive protein, and liver enzymes were analyzed. The initial positivity rates for M. pneumoniae IgM and IgA upon admission to the hospital were 63.6 and 33.8%, respectively. One week after admission, the cumulative positivity rates for M. pneumoniae IgM and IgA increased to 97.5 and 56.3%, respectively. Detection of M. pneumoniae IgM was more sensitive than detection of M. pneumoniae IgA for the diagnosis of M. pneumoniae-related pneumonia in school-age children and adolescents; however, paired sera are necessary for a more accurate diagnosis.

Severe childhood Guillain-Barré syndrome associated with Mycoplasma pneumoniae infection: a case series

We report seven children with recent Mycoplasma pneumoniae infection and severe Guillain-Barré syndrome (GBS) that presented to two European medical centres from 1992 to 2012. Severe GBS was defined as the occurrence of respiratory failure, central nervous system (CNS) involvement, or death. Five children had GBS, one Bickerstaff brain stem encephalitis (BBE), and one acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP). The five patients with severe GBS were derived from an original cohort of 66 children with GBS. In this cohort, 17 children (26%) had a severe form of GBS and 47% of patients with M. pneumoniae infection presented with severe GBS. Of the seven patients in this case series, five were mechanically ventilated and four had CNS involvement (two were comatose). Most patients presented with non-specific clinical symptoms (nuchal rigidity and ataxia) and showed a rapidly progressive disease course (71%). Antibodies against M. pneumoniae were detected in all patients and were found to be intrathecally synthesised in two cases (GBS and BBE), which proves intrathecal infection. One patient died and only two patients recovered completely. These cases illustrate that M. pneumoniae infection in children can be followed by severe and complicated forms of GBS. Non-specific clinical features of GBS in such patients may predispose a potentially life-threatening delay in diagnosis.

Encephalopathy and Axonal Neuropathy Associated With Mycoplasma Pneumoniae Infection: Response to Intravenous Immunoglobulin Therapy

Mycoplasma pneumoniae infection frequently presents as a self-limited process, however, severe cases and even fatalities have been reported. The authors present a case of Mycoplasma pneumoniae infection associated with both encephalopathy and peripheral neuropathy that responded to intravenous immunoglobulin therapy. To our knowledge, this is the first documented case of Mycoplasma pneumoniae related to encephalitis and peripheral axonal neuropathy. To date, there is insufficient data on the effect of intravenous immunoglobulin on the course of mycoplasma-associated central nervous system/peripheral nervous system disease. While intravenous immunoglobulin has aided in a variety of autoimmune-mediated disorders, its efficacy in mycoplasma-mediated encephalitis treatment remains unclear. In this patient case, reversal of both central and peripheral nervous system symptoms after treatment with intravenous immunoglobulin suggested a possible therapeutic benefit.

Hepatitis associated with Mycoplasma pneumoniae infection in Korean children: a prospective study

Purpose

Mycoplasma pneumoniae (MP) infection is a major cause of respiratory infection in school-aged children. Extrapulmonary manifestations of MP infection are common, but liver involvement has been rarely reported. The aim of this study was to determine the clinical characteristics of MP-associated hepatitis.

Methods

This prospective study included 1,044 pediatric patients with MP infection diagnosed serologically with MP IgM at one medical center from January 2006 to December 2012. Eighty of these patients had elevated levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), each greater than 50 IU/L, without any other specific liver disorder and were compared with the 964 children without liver disorders.

Results

In total, 7.7% of patients with MP infection had a diagnosis of hepatitis, especially in fall and winter. The ratio of male to female patients was 1.7:1, and the mean age of the patients was 5 years and 5 months. The most common symptoms were cough, fever, and sputum. Anorexia was the most common gastrointestinal symptom, followed by nausea/vomiting, diarrhea, and abdominal pain. Mean levels of AST and ALT were 100.65 IU/L and 118.73 IU/L, respectively. Serum AST/ALT level was normalized within 7.5 days on average without complications. The mean duration of hospitalization (11.3 days) was longer for children with hepatitis than for those without hepatitis (P=0.034).

Conclusion

MP-associated hepatitis is not uncommon and has a relatively good prognosis. Therefore, clinicians should be concerned about liver involvement in MP infection but avoid further unnecessary evaluation of hepatitis associated with MP.

Mycoplasma pneumoniae as a causative agent of community-acquired pneumonia in children: clinical features and laboratory diagnosis

BACKGROUND

Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) in children. The aim of this study was to assess the prevalence of Mycoplasma pneumoniae infection in children with CAP and find clinical, radiological and laboratory features helpful to diagnose Mycoplasma pneumoniae pneumonia. Furthermore, we evaluated the value of serology, real-time PCR (RT-PCR) and culture for the accurate diagnosis of Mycoplasma pneumoniae pneumonia.

METHODS

The study included 166 children aged between 1 and 15 years with radiologically confirmed pneumonia. Throat swab specimens were cultured and assessed by RT-PCR for the presence of Mycoplasma pneumoniae. Mycoplasma pneumoniae-specific IgM and IgG antibodies were determined using ELISA in paired sera.

RESULTS

Mycoplasma pneumoniae pneumonia was diagnosed in 14.5% CAP cases. Cough (p=0.029), headache (p=0.001) and wheezing (p=0.036) were more frequent in children with Mycoplasma pneumoniae pneumonia compared to children with pneumonia caused by other pathogens. Logistic regression analysis showed that headache (odds ratio [OR] =36.077, p=0.001) and wheezing (OR=5.681, p=0.003) were significantly associated with MP pneumonia. Neither radiological findings, nor common laboratory parameters distinguished Mycoplasma pneumoniae infection in children with CAP. Using IgG serology in paired sera as the gold standard, we found that sensitivity of IgM serology, RT-PCR and culture was equal (81.82%), while specificity values were 100%, 98.6% and 100% respectively. We observed that combination of IgM detection in acute-phase serum and RT-PCR was positive for 91.7% of cases with Mycoplasma pneumoniae infection.

CONCLUSIONS

There are no characteristic radiological findings, or routine laboratory tests that would distinguish CAP caused by Mycoplasma pneumoniae from other CAP. It was found that clinical features such as headache and wheezing are indicative for Mycoplasma pneumoniae infection. Furthermore, it was found that during the acute phase of disease, detection of IgM antibodies in combination with RT-PCR allows for precise and reliable diagnosis of Mycoplasma pneumoniae infections in children.

Genetic point-of-care diagnosis of Mycoplasma pneumoniae infection using LAMP assay

BACKGROUND

Mycoplasma pneumoniae (MP) is a major pathogen of lower respiratory tract infection (LRTI) in children. A rapid diagnostic method during the acute phase is required for the prescription of effective antibiotics.

METHODS

A prospective, single-centered study was conducted on community-acquired LRTI in children. We regarded the day of fever onset as the first day of illness. In part 1, we studied 191 patients with signs of LRTI. We compared diagnostic reliability using loop-mediated isothermal amplification (LAMP) assay and serological testing at the first visit. In part 2, we evaluated the clinical characteristics of 117 patients with positive LAMP assay.

RESULTS

In part 1, 31 patients met the definite MP infection criteria. LAMP assay had a sensitivity of 96.8% and specificity of 100%, whereas enzyme immunoassay had a sensitivity of 38.7% and specificity of 76.9%, and particle agglutination test had a sensitivity of 19.4% and specificity of 93.1%. In part 2, of 106 patients with fever, 100 patients were diagnosed by the day 7 of illness. The diagnosis was made a mean of 3.5 ± 2.1 days after the onset of fever.

CONCLUSIONS

LAMP assay had excellent sensitivity and specificity for the detection of acute MP infection at the first visit. This assay can diagnose MP infection during the very acute phase. LAMP assay is appropriate for genetic point-of-care diagnosis of MP infection in hospital laboratories.

Age-specific Mycoplasma pneumoniae pneumonia-associated myocardial damage in children

OBJECTIVE

To measure Mycoplasma pneumoniae pneumonia (MPP)-associated myocardial damage in different age groups of children with pneumonia.

METHODS

Children aged 0-14 years with pneumonia and myocardial damage (serum creatine kinase isoenzyme-MB [CK-MB] concentration >25 U/l) were enrolled in the study. The children were classified as Mycoplasma pneumoniae immunoglobulin M positive (M. pneumoniae IgM+) or negative (M. pneumoniae IgM-) based on a serological test. Children were stratified into four age groups in order to analyse age-specific MPP-associated myocardial damage.

RESULTS

The incidence of fever was significantly higher in children who were M. pneumoniae IgM+ compared with M. pneumoniae IgM- children. The median serum CK-MB concentration was significantly higher in children who were M. pneumoniae IgM+ compared with those who were M. pneumoniae IgM-. Children who were M. pneumoniae IgM+ in the 13-36 months and 72 months-14 years age groups had significantly higher median serum CK-MB concentrations than those who were M. pneumoniae IgM- in the same age group.

CONCLUSIONS

M. pneumoniae infection was associated with greater myocardial damage in children aged 13-36 months and 72 months-14 years. This suggests age-specific immune responses to M. pneumoniae.

Coexistence of myositis, transverse myelitis, and Guillain Barré syndrome following Mycoplasma pneumoniae infection in an adolescent

Guillain-Barré syndrome (GBS) and transverse myelitis may occur coexistently in the pediatric population. This may be explained by a shared epitope between peripheral and central nervous system myelin. Coexistent transverse myelitis, myositis, and acute motor neuropathy in childhood have not been previously described. We describe a 14-year-old female patient with transverse myelitis, myositis, and GBS following Mycoplasma pneumoniae infection. She presented with weakness and walking disability. Weakness progressed to involve all extremities and ultimately, she was unable to stand and sit. Based on the clinical findings, a presumptive diagnosis of myositis was made at an outside institution because of high serum creatine kinase level. The patient was referred to our institution for further investigation. Magnetic resonance imaging of spine revealed enhancing hyperintense lesions in the anterior cervicothoracic spinal cord. The electromyography revealed acute motor polyneuropathy. Serum M. pneumoniae IgM and IgG were positive indicating an acute infection. Repeated M. pneumoniae serology showed a significant increase in Mycoplasma IgG titer. The patient was given intravenous immunoglobulin for 2 days and clarithromycin for 2 weeks. She was able to walk without support after 2 weeks of hospitalization. This paper emphasizes the rarity of concomitant myositis, transverse myelitis, and GBS in children.

Accuracy of IgM antibody testing, FQ-PCR and culture in laboratory diagnosis of acute infection by Mycoplasma pneumoniae in adults and adolescents with community-acquired pneumonia

Background

Diagnosis of community-acquired pneumonia (CAP) caused by Mycoplasma pneumoniae in adults and adolescents is hampered by a lack of rapid and standardized tests for detection.

Methods

CAP patients from 12 teaching hospitals were prospectively and consecutively recruited. Basic and clinical information, throat swabs and paired sera were collected. Mycoplasma pneumoniae was detected by IgG and IgM antibody tests, fluorescence quantitative polymerase chain reaction (FQ-PCR) and culture. A comparative study of the diagnostic values of three methods, including sensitivity, specificity, positive and negative predictive values and positive likelihood ratio (PLR) was conducted. A fourfold or greater increase of IgG antibody titers of paired sera was set as the diagnostic “gold standard”.

Results

One hundred and twenty-five CAP patients (52.8% males, median age 47 years, range 14–85) were enrolled. Twenty-seven (21.6%) patients were diagnosed with acute Mycoplasma pneumoniae infections by the “gold standard”. Specificity values of all three methods were around 90%. An increasing trend of sensitivity, positive predictive value and PLR was found, with the lowest in IgM testing (7.4%, 28.6% and 1.45), intermediate in FQ-PCR (40.7%, 50% and 3.63), and highest in culture (55.6%, 75% and 10.9).

Conclusions

In the defined group of patients, there was a good agreement between positive rate of MP cultivation of throat swabs and acute M. pneumoniae infection (PLR of 10.9). Since the sensitivity is low in all of the evaluated methods, the logical approach would be to incorporate PCR, culture and serological tests for optimum diagnosis of acute Mycoplasma pneumoniae infections in adults and adolescents.

Respiratory viral infections among children with community-acquired pneumonia and pleural effusion

Pleural effusion (PE), a complication of community-acquired pneumonia (CAP), is usually attributed to a bacterial infection. Nonetheless, viral infections have not been investigated routinely. We searched for bacterial and viral infections among 277 children hospitalized with CAP. Among these children 206 (74%) had radiographic confirmation, of whom 25 (12%) had PE. The aetiology was established in 18 (72%) PE cases: bacterial (n = 5; 28%), viral (n = 9; 50%), and viral-bacterial (n = 4; 22%) infections were found. Infection by rhinovirus (n = 3), enterovirus, Streptococcus pneumoniae (n = 2 each), Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, influenza A virus, and respiratory syncytial virus (RSV) (n = 1 each) were detected as probable sole infections. Parainfluenza virus 1/3 + influenza A virus and RSV + influenza A virus (n = 1 each) were identified as mixed viral-viral infections. Probable viral non-bacterial infection was identified in a third of the cases with CAP and PE. It is advisable to investigate viral as well as bacterial infections among children with CAP and PE.

Epidemiology of community-acquired Mycoplasma Pneumoniae respiratory tract infections among hospitalized Chinese children, including relationships with meteorological factors

BACKGROUND

Mycoplasma Pneumoniae (M. pneumoniae) is a common cause of respiratory tract infections (RTIs), especially in children. Combined diagnostic techniques have provided more reliable information about the epidemiology of infections by this pathogen. The relationship between M. pneumoniae RTIs and climatic conditions is not well documented in the literature.

AIMS

To study the epidemiology of M. pneumoniae infections in hospitalized children with RTIs and its association with meteorological factors.

METHODS

Samples were obtained from children with RTIs and tested for M. pneumoniae by PCR and ELISA. Meanwhile, meteorological factors were recorded.

RESULTS

M. pneumoniae was identified in 11.02% of the 8,157 specimens. There were significant differences among the annual distribution of infections (χ(2) =130.13, P<0.0001) and among different seasons (χ(2) =93.59, P<0.0001). Of the total number of patients with M. pneumoniae infections, 14.5% were infected with more than one pathogen. M. pneumoniae infection strongly correlated with mean temperature. Children with a single M. pneumoniae infection had significantly higher neutrophil percentages and CRP levels than children with co-infections.

CONCLUSIONS

M. pneumoniae is one of the most commonly held pathogens, according to the 5-year surveillance. M. pneumoniae infection has its own epidemic season, especially in the summer. Mean temperature is the main meteorological factor affecting the epidemiology of M. pneumoniae infections.

Mycoplasma pneumoniae-related community-acquired pneumonia and parapneumonic pleural effusion in children and adolescents

OBJECTIVE

To determine the prevalence and the characteristics of Mycoplasma pneumoniae-related community-acquired pneumonia (CAP) and parapneumonic pleural effusion (PPE) in children and adolescents.

METHODS

This was a retrospective observational study involving 121 patients with CAP/PPE hospitalized in a tertiary referral hospital between 2000 and 2008, divided into six groups according to the etiologic agent (G1 to G6, respectively): M. pneumoniae with or without co-infection, in 44 patients (group 1); etiologic agents other than M. pneumoniae, in 77 (group 2); M. pneumoniae without co-infection, in 34 (group 3); Streptococcus pneumoniae, in 36 (group 4); Staphylococcus aureus, in 31 (group 5); and M. pneumoniae/S. pneumoniae co-infection, in 9 (group 6).

RESULTS

In comparison with group 2, group 1 showed higher frequencies of females, dry cough, and previous use of beta-lactam antibiotics; longer duration of symptoms prior to admission; and lower frequencies of use of mechanical ventilation and chest tube drainage. In comparison with groups 4 and 5, group 3 showed higher frequencies of previous use of beta-lactam antibiotics and dry cough; longer duration of symptoms prior to admission; a lower frequency of use of chest tube drainage; a higher mean age and a lower frequency of nausea/vomiting (versus group 4 only); and a lower frequency of use of mechanical ventilation (versus group 5 only). M. pneumoniae/S. pneumoniae co-infection increased the duration of symptoms prior to admission.

CONCLUSIONS

In this sample, the prevalence of M. pneumoniae-related CAP/PPE was 12.75%. Although the disease was milder than that caused by other microorganisms, its course was longer. Our data suggest that M. pneumoniae-related CAP and PPE in children and adolescents should be more thoroughly investigated in Brazil.

A case of acute myopericarditis associated with Mycoplasma pneumoniae infection in a child

Mycoplasma pneumoniae (M. pneumoniae) primarily causes respiratory tract infections in persons aged 5-20 years. Tracheobronchitis and bronchopneumonia are the most commonly recognized clinical symptoms associated with M. pneumoniae infection. Complications of this infection are unusual; in particular, cardiac involvement is very rare and is generally accompanied by pneumonia. Nonrespiratory illness can therefore involve direct invasion by M. pneumoniae or autoimmune mechanisms, as suggested by the frequency of cross reaction between human antigens and M. pneumoniae. Herein, we report a case of severe acute myopericarditis with pneumonia caused by M. pneumoniae in a healthy young child who presented with fever, lethargy, oliguria and dyspnea. She survived with aggressive therapy including clarithromycin, intravenous immunoglobulin, inotropics, and diuretics. The patient was discharged on the 19th day after admission and followed up 1 month thereafter at the outpatient clinic without sequelae.

Investigation of Mycoplasma pneumoniae infection in pediatric population from 12,025 cases with respiratory infection

Although Mycoplasma pneumoniae (MP) is a major pathogen of primary atypical pneumonia in children, the clinical and laboratory characteristics of MP infection in large pediatric population are less reported. Here, we retrospectively analyzed 12,025 hospitalized children with respiratory infection by using serology and polymerase chain reaction (PCR) methods simultaneously. The results showed that 2433 (20.23%) children had MP infection, which mainly occurred in November to April. The presence of sore throat and pharyngitis was peculiar to MP infection. The positive percentage of MP-DNA was higher than that of MP-IgM in children aged <1 (P < 0.0001) and 1-3 years (P < 0.0001). Moreover, the positive rate of P1 gene, the key adhesion gene for MP infection, was higher in children with MP infection than in those with other pathogens (P < 0.0001). Our work provides the clinical information of children MP infection and highlights the superiority of PCR and potential usage of P1 as a diagnosis target for MP infection.

Mycoplasma pneumoniae and mucositis--part of the Stevens-Johnson syndrome spectrum

BACKGROUND

Mycoplasma pneumoniae may induce mucosal inflammation, referred to as M. pneumoniae-associated mucositis (MPAM). There is no generally accepted definition of MPAM, since there may be mucosal lesions only, or mucosal and minimal skin lesions.

PATIENTS AND METHODS

We conducted a literature review of MPAM, paying particular attention to pathogenesis, clinical manifestations, treatment decisions, and prognosis.

RESULTS

We identified 32 cases of MPAM (median age 13.5 years), whereof 23 patients were otherwise healthy children and young adolescents (72%). M. pneumoniae infection was associated with fever and respiratory symptoms in all calls; it was confirmed by serology (n = 30) and/or PCR (n = 9). Oral lesions were present in all cases, followed by ocular (97%) and uro-genital lesions (78%). Despite the syndrome's name postulating the absence of cutaneous involvement, minimal skin lesions occurred in 31%. Treatment regimens included systemic antibiotics (100%) and systemic anti-inflammatory treatment with corticosteroids (31%) or immunoglobulins (9%). Macrolides were given in 81%, with failure, relapse, and/or worsening in one-third of patients. No patient suffered long-term sequelae.

CONCLUSION

MPAM is a distinct extra-pulmonary manifestation falling into the continuum of Stevens-Johnson syndrome. This entity may be due to inflammatory mechanisms suggesting that systemic anti-inflammatory treatment is even more important than antimicrobials.

The management of community-acquired pneumonia in infants and children older than 3 months of age: clinical practice guidelines by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America

Evidenced-based guidelines for management of infants and children with community-acquired pneumonia (CAP) were prepared by an expert panel comprising clinicians and investigators representing community pediatrics, public health, and the pediatric specialties of critical care, emergency medicine, hospital medicine, infectious diseases, pulmonology, and surgery. These guidelines are intended for use by primary care and subspecialty providers responsible for the management of otherwise healthy infants and children with CAP in both outpatient and inpatient settings. Site-of-care management, diagnosis, antimicrobial and adjunctive surgical therapy, and prevention are discussed. Areas that warrant future investigations are also highlighted.

Detection of Mycoplasma pneumoniae in different respiratory specimens

Mycoplasma pneumoniae (M. pneumoniae) is an important community-acquired pneumonia pathogen. Serological test and polymerase chain reaction (PCR) assay are the two main laboratory tests to detect M. pneumoniae now. Little information was compared about the sensitivity and specificity of PCR using different specimens including bronchoalveolar lavage (BAL) and nasopharyngeal aspirate (NPA). The aim of the present study was to evaluate diagnostic values of different specimens by fluorescence quantitative real-time PCR and to find clinical features helpful to diagnose M. pneumoniae pneumonia (MPP). Four hundred and six hospitalized pneumonia children were studied. M. pneumoniae DNA in NPA and BAL samples were detected by fluorescence quantitative real-time PCR. M. pneumoniae-specific IgM was tested by ELISA. MPP were diagnosed based on positive M. pneumoniae-specific IgM in 101 (24.9%) children. The median ages of MPP and non-MPP children were 4.1 and 2.4 years, respectively, with significant difference between them (p < 0.001). Laboratory results including leukocyte count, neutrophil percentage, immunoglobulins, except serum IgM, subgroups of T lymphocyte, and BAL cell count had no significant differences in MPP and non-MPP. BAL macrophage cell percentage was lower in BAL-PCR positive children (p = 0.003), while BAL neutrophil percentage was higher in BAL-PCR positive children (p = 0.007). PCR from NPA and BAL were similar in diagnostic parameters, including sensitivity, specificity, PPV, and NPV (78.6%, 63.4%, 39.8%, and 90.6% for NPA-PCR, respectively; 70.3%, 58.7%, 36.0%, and 85.6% for BAL-PCR, respectively).

CONCLUSIONS

NPA is better than BAL as PCR sample in MPP diagnosis for similar performance in PCR assay, cheap, and less invasive. BAL is useful in defining local inflammatory condition. Age is the only prefigurative factor in MPP.

Mycoplasma pneumoniae respiratory tract infections among Greek children

BACKGROUND

M. pneumoniae is a common cause of respiratory tract infections (RTIs) of variable severity especially in children. New diagnostic techniques offered more reliable information about the epidemiology of infection by this pathogen.

AIM

The aim of this study was to investigate the prevalence and epidemiology of acute M. pneumoniae infections among Greek children hospitalized for RTIs using more advanced techniques.

MATERIAL AND METHODS

The study included 225 Greek children hospitalized for RTIs during a 15-month period. Throat swab specimens were tested by PCR for the detection of M. pneumoniae, while IgG and IgM antibodies were determined by ELISA and, in certain cases, also by western-blot. In parallel, specimens were tested for the presence of additional respiratory pathogens.

RESULTS

M. pneumoniae infection was diagnosed as the only pathogen in 25 (11.1%) cases, being the second (after respiratory syncytial virus- RSV) most often detected pathogen. The proportion of cases with M. pneumoniae infection in age group 8-14 years (23.3%) was significantly higher than that in <3 years age group.

CONCLUSION

During our study period, M. pneumoniae was the second causative agent of RTIs after RSV. The proportion of children with M. pneumoniae RTIs increased with age, while most cases were reported during summer and autumn.

Prevalence of Mycoplasma pneumoniae-associated respiratory tract infections in hospitalized children: results of a 4-year prospective study in Tunis

Specific microbiologic, molecular, and serologic assays are hardly available in Tunis to confirm a suspected infection of Mycoplasma pneumoniae (MP). These diagnosis methods were used for the first time in a Tunisian prospective study to estimate the prevalence of MP infection in children and to evaluate their usefulness for diagnosis. A total of 540 children hospitalized in Tunis for lower respiratory tract infections (LRTIs) between 2005 and 2009 and 580 clinical specimens were investigated for the presence of MP by culture and by end-point polymerase chain reaction (PCR) targeting the P1 and the 16S rRNA genes. Real-time PCR was also used for MP detection on 158 respiratory samples. A total of 525 serum samples were tested for detection of MP-specific IgM and IgG. The P1 adhesin type and the antibiotic susceptibility testing were determined for the 9 clinical strains isolated during the study period. MP was detected in 33 (5.7%) clinical samples. Specific MP seropositivity was confirmed in 54 serum samples (10.3%), among which 19 (3.6%) were indicative of acute MP infection. MP infection was confirmed in 39 (7.2%) patients: 24 positive by PCR and/or culture, 10 serologically positive only, and 5 confirmed positive by both methods. MP infections occurred throughout the year with a slight decrease in autumn. The 9 MP isolates were susceptible to erythromycin, tetracycline, and ciprofloxacin, and all belonged to type I. The prevalence of MP infection in children with LRTI was 7.2% between 2005 and 2009, in Tunisia. Combination of direct detection and serology was required to enhance the clinical sensitivity of MP detection in clinical specimens.

Identification of an N-terminal 27 kDa fragment of Mycoplasma pneumoniae P116 protein as specific immunogen in M. pneumoniae infections

BACKGROUND

Mycoplasma pneumoniae is an important cause of respiratory tract infection and is increasingly being associated with other diseases such as asthma and extra-pulmonary complications. Considerable cross-reactivity is known to exist between the whole cell antigens used in the commercial serological testing assays. Identification of specific antigens is important to eliminate the risk of cross-reactions among different related organisms. Adherence of M. pneumoniae to human epithelial cells is mediated through a well defined apical organelle to which a number of proteins such as P1, P30, P116 and HMW1-3 have been localized, and are being investigated for adhesion, gliding and immunodiagnostic purposes.

METHODS

A 609 bp fragment P116(N-27), corresponding to the N-terminal region of M. pneumoniae P116 gene was cloned and expressed. A C-terminal fragment P1(C-40), of P1 protein of M. pneumoniae was also expressed. Three IgM ELISA assays based on P116(N-27), P1(C-40) and (P116 (N-27) + P1(C-40)) proteins were optimized and a detailed analysis comparing the reactivity of these proteins with a commercial kit was carried out. Comparative statistical analysis of these assays was performed with the SPSS version 15.0.

RESULTS

The expressed P116(N-27) protein was well recognized by the patient sera and was immunogenic in rabbit. P1(C-40) of M. pneumoniae was also immunogenic in rabbit. In comparison to the reference kit, which is reported to be 100% sensitive and 75% specific, ELISA assay based on purified P116(N-27), P1(C-40) and (P116(N-27) + P1(C-40)) proteins showed 90.3%, 87.1% and 96.8% sensitivity and 87.0%, 87.1% and 90.3% specificity respectively. The p value for all the three assays was found to be < 0.001, and there was a good correlation and association between them.

CONCLUSION

This study shows that an N-terminal fragment of P116 protein holds a promise for serodiagnosis of M. pneumoniae infection. The IgM ELISA assays based on the recombinant proteins seem to be suitable for the use in serodiagnosis of acute M. pneumoniae infections. The use of short recombinant fragments of P116 and P1 proteins as specific antigens may eliminate the risk of cross-reactions and help to develop a specific and sensitive immunodiagnostic assay for M. pneumoniae detection.

Limited utility of culture for Mycoplasma pneumoniae and Chlamydophila pneumoniae for diagnosis of respiratory tract infections

We assessed the utility of culture for Mycoplasma pneumoniae and Chlamydophila pneumoniae to diagnose respiratory tract infections. Compared to PCR and IgM serology, culture was less sensitive and had extremely low yield. Culture is not recommended for these pathogens, and this method should be eliminated from routine practice.

Seasonal patterns of viral and bacterial infections among children hospitalized with community-acquired pneumonia in a tropical region

Community-acquired pneumonia (CAP) is a common cause of morbidity among children. Evidence on seasonality, especially on the frequency of viral and bacterial causative agents is scarce; such information may be useful in an era of changing climate conditions worldwide. To analyze the frequency of distinct infections, meteorological indicators and seasons in children hospitalized for CAP in Salvador, Brazil, nasopharyngeal aspirate and blood were collected from 184 patients aged < 5 y over a 21-month period. Fourteen microbes were investigated and 144 (78%) cases had the aetiology established. Significant differences were found in air temperature between spring and summer (p = 0.02) or winter (p < 0.001), summer and fall (p = 0.007) or winter (p < 0.001), fall and winter (p = 0.002), and on precipitation between spring and fall (p = 0.01). Correlations were found between: overall viral infections and relative humidity (p = 0.006; r = 0.6) or precipitation (p = 0.03; r = 0.5), parainfluenza and precipitation (p = 0.02; r = -0.5), respiratory syncytial virus (RSV) and air temperature (p = 0.048; r = -0.4) or precipitation (p = 0.045; r = 0.4), adenovirus and precipitation (p = 0.02; r = 0.5), pneumococcus and air temperature (p = 0.04; r = -0.4), and Chlamydia trachomatis and relative humidity (p = 0.02; r = -0.5). The frequency of parainfluenza infection was highest during spring (32.1%; p = 0.005) and that of RSV infection was highest in the fall (36.4%; p < 0.001). Correlations at regular strength were found between several microbes and meteorological indicators. Parainfluenza and RSV presented marked seasonal patterns.

Acute respiratory infection due to Mycoplasma pneumoniae: current status of diagnostic methods

Because of the absence of well-standardized both in-house and FDA-approved commercially available diagnostic tests, the reliable diagnosis of respiratory infection due to Mycoplasma pneumoniae remains difficult. In addition, no formal external quality assessment schemes which would allow to conclude about the performance of M. pneumoniae diagnostic tests exist. In this review, the current state of knowledge of M. pneumoniae-associated respiratory infections in the context of epidemiological studies published during the past 5 years is discussed, with particular emphasis on the diagnostic strategies used and their impact on results. The role of M. pneumoniae as a cause of respiratory tract infections (RTIs) differs from study to study due to geographical and epidemiological differences, as well as to the application of different diagnostic techniques and criteria used.

Mycoplasma pneumoniae associated opsoclonus-myoclonus syndrome in three cases

Opsoclonus-myoclonus syndrome (OMS) is a rare acquired movement disorder occurring in all age groups, predominantly in infants. Although the exact pathogenesis is still undefined, there is strong evidence for a paraneoplastic or parainfectious immune process resulting in central nervous system dysfunction. Mycoplasma pneumoniae has been implicated in a number of immune-mediated neurologic diseases [28]. However, the association of M. pneumoniae and opsoclonus-myoclonus-ataxia syndrome is not well established so far. We present three cases with opsoclonus-myoclonus-ataxia syndrome in adolescents following an infection with M. pneumoniae. Monophasic disease course and full recovery correspond to the favorable prognosis known from parainfectious cases in young adults. This should affect therapeutic consideration. OMS should be added to the spectrum of M. pneumoniae-associated neurologic complications. Nevertheless, neuroblastoma has to be ruled out in all cases of OMS.

Microfluidic platform versus conventional real-time polymerase chain reaction for the detection of Mycoplasma pneumoniae in respiratory specimens

Rapid, accurate diagnosis of community-acquired pneumonia (CAP) due to Mycoplasma pneumoniae is compromised by low sensitivity of culture and serology. Polymerase chain reaction (PCR) has emerged as a sensitive method to detect M. pneumoniae DNA in clinical specimens. However, conventional real-time PCR is not cost-effective for routine or outpatient implementation. Here, we evaluate a novel microfluidic real-time PCR platform (Advanced Liquid Logic, Research Triangle Park, NC) that is rapid, portable, and fully automated. We enrolled patients with CAP and extracted DNA from nasopharyngeal wash (NPW) specimens using a biotinylated capture probe and streptavidin-coupled magnetic beads. Each extract was tested for M. pneumoniae-specific DNA by real-time PCR on both conventional and microfluidic platforms using Taqman probe and primers. Three of 59 (5.0%) NPWs were positive, and agreement between the methods was 98%. The microfluidic platform was equally sensitive but 3 times faster and offers an inexpensive and convenient diagnostic test for microbial DNA.

A retrospective study of the patients with positive ImmunoCard Mycoplasma test on an outpatient clinic basis

The simplified ImmunoCard Mycoplasma test for rapidly detecting Mycoplasma pneumoniae-specific IgM antibodies has been widely used. We examined the usefulness of this test for outpatient practices as well as for the association with bronchial asthma. Among 196 patients whose ImmunoCard showed positive, we targeted 57 cases in which we were able to perform this test multiple times. We evaluated the degree of inflammatory response in the laboratory findings at the time of the test, the period until negative seroconversion for antibodies, and the course of their pulmonary function findings. The number of days from the onset of pyrexia until the test was a median of 10 (range 2-70) days, wherein the inflammatory response did not have a significant effect on that number of days. In 35 cases in which we observed the seroconversion to negative for antibodies, the period of the positive phase was 180 (21-421) days, wherein it was significantly longer for smokers. We observed exacerbation in the majority of the asthma patients, and some of the non-asthmatic patients showed either asthma or asthma-like clinical conditions. For ImmunoCard-positive individuals, it is desirable to ascertain the history of respiratory infection retrospectively to about half a year, although this test is known to suffer from lack of both of sensitivity and specificity. Additionally, it is necessary for ImmunoCard-positive patients to pay attention to the exacerbation of asthma and the development of asthma thereafter.

Prevalence of Mycoplasma IgM in children with lower respiratory tract illness

BACKGROUND

Few data are available for the recent occurrence of Mycoplasma infections in children in Japan. The purpose of the present study was therefore to identify the prevalence of Mycoplasma infections in children in Japan.

METHODS

IgM antibodies to M. pneumoniae were prospectively determined using the Meridian ImmunoCard Mycoplasma test in hospitalized patients with lower respiratory tract infections between January 2004 and June 2007. A total of 858 hospitalized patients aged 0-15 years (445 male, 413 female), diagnosed as having acute pneumonia or bronchitis, were enrolled. The number of patients with pneumonia or bronchitis was 331 (male/female, 167/164) and 527 (male/female/ 278/249), respectively. Two hundred and five of the 858 patients (23.9%) were ImmunoCard positive. Of the 205 patients, 121 children and 84 children were diagnosed as having pneumonia and bronchitis, respectively. One hundred and forty-three of the 727 patients (19.7%) <5 years of age were ImmunoCard test positive.

CONCLUSIONS

M. pneumoniae infection is not rare in children aged <5 years in Japan.

Mycoplasma pneumoniae-associated mucositis with minimal skin manifestations

Mycoplasma pneumoniae-associated mucositis is a rarely described complication of M. pneumoniae infection presenting with ocular, oral, and genital involvement but without the typical skin lesions seen in Stevens-Johnson syndrome. A 27-year-old man with a past history of asthma presented at the emergency room with a 1-week history of cough (initially non-productive but subsequently associated with non-bloody mucopurulent sputum), fever, myalgias, headache, and progressive dyspnea. Two days before admission he had commenced amoxicillin/clavulanic acid with no improvement. The patient reported bilateral conjunctival injection and hemorrhagic ulcers on the lips commencing the day prior to admission. Physical examination revealed fever (39 degrees C), bilateral exudative conjunctivitis, painful hemorrhagic ulcers on the lips, tongue, and oral mucosa, small scrotal erosions, erythema of the penile meatus, and small erythematous bullae on the dorsum of each hand; subsequently, the patient developed bullae at the venipuncture site on his right arm. Laboratory tests revealed positive IgM serology for M. pneumoniae, with titer elevation. The patient was successfully treated with levofloxacin and prednisolone. Our case appears to be the first adult patient described with M. pneumoniae-associated mucositis, which has previously been reported only in pediatric patients. This is also the first reported instance of a case of M. pneumoniae-associated mucositis treated with levofloxacin and prednisolone. M. pneumoniae infection should be considered in all cases of mucositis, and treatment of this condition with levofloxacin and prednisolone seems to be effective.