Mycoplasma pneumoniae: nervous system complications in childhood and review of the literature

An accurate and convenient method for Mycoplasma pneumoniae via one-step LAMP-CRISPR/Cas12b detection platform

Introduction

Mycoplasma pneumoniae (MP) is the major cause of respiratory infections that threaten the health of children and adolescents worldwide. Therefore, an early, simple, and accurate detection approach for MP is critical to prevent outbreaks of MP-induced community-acquired pneumonia.

Methods

Here, we explored a simple and accurate method for MP identification that combines loop-mediated isothermal amplification (LAMP) with the CRISPR/Cas12b assay in a one-pot reaction.

Results

In the current study, the whole reaction was completed within 1 h at a constant temperature of 57°C. The limit of detection of this assay was 33.7 copies per reaction. The specificity of the LAMP-CRISPR/Cas12b method was 100%, without any cross-reactivity with other pathogens. Overall, 272 clinical samples were used to evaluate the clinical performance of LAMP-CRISPR/Cas12b. Compared with the gold standard results from real-time PCR, the present method provided a sensitivity of 88.11% (126/143), specificity of 100% (129/129), and consistency of 93.75% (255/272).

Discussion

Taken together, our preliminary results illustrate that the LAMP-CRISPR/Cas12b method is a simple and reliable tool for MP diagnosis that can be performed in resource-limited regions.

Analysis of the relation between cerebrospinal fluid antibody titers and clinical characteristics in pediatric patients with anti-N-methyl-D-aspartate receptor encephalitis

OBJECTIVE

This retrospective study aimed to investigate the relationship between cerebrospinal fluid (CSF) antibody titers of N-methyl-d-aspartate receptor (NMDAR), and clinical characteristics in pediatric patients with anti-NMDAR encephalitis.

METHODS

The clinical and laboratory characteristics of hospitalized patients with anti-NMDAR encephalitis, stratified by antibody titers in CSF and disease severity, were retrospectively studied. The demographics, clinical characteristics, main accessory examinations, immunotherapy, and prognosis of patients were recorded, and each observed indicator was statistically analyzed.

RESULTS

A total of 103 pediatric anti-NMDAR encephalitis patients were enrolled in the study, including 41 males (39.8%) and 62 females (60.2%) with a mean age of 8.0 ± 4.0 years. The proportion of patients with cognitive dysfunction and the positive pathogen was higher in the high-titer group than in the low-titer group (p = 0.023, p = 0.042). Consciousness disturbance that occurred as an initial symptom or during the course in the severe group was higher than in the non-severe group (p = 0.002, p < 0.001). More patients in the high-titer group received plasma exchange (PE) than in the low-titer group (p = 0.022). The cure rate of patients was higher with PE (65.2%) than with Corticosteroids and (or) intravenous immunoglobulin (58.1%).

CONCLUSIONS

Patients with symptoms of disturbance of consciousness may be severer. The severity in pediatric anti-NMDAR encephalitis patients was not correlated with anti-NMDAR antibody titers. Patients with high CSF antibody titers had a better prognosis after early PE therapy.

Determining the Clinical Characteristics, Treatment Strategies, and Prognostic Factors for Mycoplasma pneumoniae Encephalitis in Children: A Multicenter Study in China

BACKGROUND AND PURPOSE

Most of the knowledge of Mycoplasma pneumonia (M. pneumoniae) encephalitis (MPE) in children is based on case reports or small case series. This study aimed to describe the clinical features and prognostic factors of MPE, and the efficacy of azithromycin with or without immunomodulatory therapy.

METHODS

The medical data of 87 patients with MPE from 3 medical centers in southwestern China over a 7-year period were reviewed.

RESULTS

MPE was found in children of all ages except for neonates. The most common neurological manifestations included consciousness disturbance (90%) and headache (87.4%), the most common extraneurological manifestations included fever (96.5%) and respiratory system involvement (94.3%); multisystem involvement (98.2%) and elevated C-reactive protein (CRP) (90.8%) were also prominent. M. pneumoniae was detected in cerebrospinal fluid (CSF) less often than in blood and respiratory tract secretions. Azithromycin with intravenous immunoglobulin or/and corticosteroid treatment can shorten the hospitalization duration and the clinical improvement process. Most patients (82.8%) received a favorable prognosis; serum lactate dehydrogenase (LDH) and CSF protein levels were higher in the poor-outcome group than in the good-outcome group (p<0.05). Neurological sequelae are likely to continue when the onset of this condition occurs during teenage years.

CONCLUSIONS

MPE generally presented with nonspecific clinical manifestations. In children with acute encephalitis accompanied by multi-system involvement and prominently elevated CRP, M. pneumoniae should be considered as a possible pathogen. Immunomodulating therapies should be recommended regardless of the duration of the prodromal period. High CSF protein level, blood LDH elevation, and higher age may be associated with an unfavorable outcome.

The Coexistence of Antibodies to Neuronal Cell and Synaptic Receptor Proteins, Gangliosides and Selected Neurotropic Pathogens in Neurologic Disorders in Children

Various primarily non-autoimmune neurological disorders occur synchronously with autoantibodies against tissues in the nervous system. We aimed to assess serum and cerebrospinal fluid (CSF) autoantibodies in children with neurologic disorders. To find new diagnostic tools, we compared the laboratory and clinical findings between the distinguished groups. Retrospectively, 508 patients were divided into six subgroups: neuroinfections, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, neurologic autoimmune and demyelinating diseases, epilepsy, pervasive developmental disorders and other patients. We analysed serum anti-aquaporin-4, antiganglioside, neuronal antinuclear and cytoplasmic antibodies, as well as antibodies against surface neuronal and synaptic antigens in the CSF and serum. We involved available demographic and clinical data. Autoantibodies appeared in 165 (32.3%) children, with 24 showing multiple types of them. The most common were anti-neuroendothelium (anti-NET), anti-N-Methyl-D-Aspartate receptor (anti-NMDAr), anti-glial fibrillary acidic protein and anti-myelin antibodies bothering 46/463 (9.9%), 32/343 (9.4%), 27/463 (5.8%) and 27/463 (5.8%), respectively. Anti-NET and anti-NMDAr antibodies appeared more frequently in children with autoimmunity (p = 0.017; p < 0.001, respectively), increasing the autoimmune disease risk (OR = 2.18, 95% CI 1.13–13.97; OR = 3.91, 95% CI 1.86–8.22, respectively). Similar pathomechanisms appeared in diseases of different aetiology with clinical spectrums mimicking each other, so we proposed the model helping to diagnose autoimmune disease. We proved the influence of age, living place and medical history on the final diagnosis.

Performance Analysis of Novel Nucleic Acid Detection Kit for Mycoplasma pneumoniae

Respiratory tract infections caused by Mycoplasma pneumoniae is a serious risk for child health. It has been difficult to prevent and control for a variety of reasons; therefore, timely diagnosis is particularly important for treatment of patients. At present, the rapid M pneumoniae test kits based on nucleic acid amplification have been commercialized and used as primary diagnostic tools for M pneumoniae infection, but current kits are time-consuming, which is difficult to meet the requirement for accurate and rapid diagnosis of M pneumoniae during epidemics. Rapid and accurate test kits are urgently required to diagnose M pneumoniae infection. In this article, we evaluated the performance of a novel nucleic acid detection kit (A) for M pneumoniae from feasibility and sensitivity, and compared it with kit B. Results showed this kit has the advantage of being rapid, sensitive, and specific, which meets the demands for the diagnosis of M pneumoniae infection in clinical settings.

Clinical Characteristics of Macrolide-Refractory Mycoplasma pneumoniae Pneumonia in Korean Children: A Multicenter Retrospective Study

Mycoplasma pneumoniae is a major causative pathogen of community-acquired pneumonia in children, and the treatment of choice is macrolides. There is an increasing trend in reports of refractory clinical responses despite macrolide treatment due to the emergence of macrolide-resistant M. pneumoniae. Early discrimination of macrolide-refractory M. pneumoniae pneumonia (MrMP) from macrolide-sensitive M. pneumoniae pneumonia (MSMP) is vital; however, testing for macrolide susceptibility at the time of admission is not feasible. This study aimed to identify the characteristics of MrMP in Korean children, in comparison with those of MSMP. In this multicenter study, board-certified pediatric pulmonologists at 22 tertiary hospitals reviewed the medical records from 2010 to 2015 of 5294 children who were hospitalized with M. pneumoniae pneumonia and administered macrolides as the initial treatment. One-way analysis of variance and the Kruskal-Wallis test were used to compare differences between groups. Of 5294 patients (mean age, 5.6 years) included in this analysis, 240 (4.5%), 925 (17.5%), and 4129 (78.0%) had MrMP, macrolide-less effective M. pneumoniae pneumonia, and MSMP, respectively. Compared with the MSMP group, the MrMP group had a longer fever duration, overall (13.0 days) and after macrolide use (8.0 days). A higher proportion of MrMP patients had respiratory distress, pleural effusion, and lobar pneumonia. The mean aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and C-reactive protein levels were the highest in the MrMP group, along with higher incidences of extrapulmonary manifestations and atelectasis (during and post infection). Pre-existing conditions were present in 17.4% (n = 725/4159) of patients, with asthma being the most common (n = 334/4811, 6.9%). This study verified that MrMP patients show more severe initial radiographic findings and clinical courses than MSMP patients. MrMP should be promptly managed by agents other than macrolides.

Dual arterial thrombosis: A diagnostic enigma

Cold agglutinin disease is a rare cause of arterial thrombosis leading to stroke, commonly encountered against a background of mycoplasma pneumonia infections. A 22-year-old patient presented with acute-onset left hemiplegia preceded by a short history of fever and cough. Magnetic resonance imaging (MRI) showed a right middle cerebral artery infarct. Serially repeated hemoglobin levels showed a progressive drop and peripheral smear showed evidence of hemolysis. Blood drawn for investigations would rapidly clot, suggesting a possibility of cold agglutinin-induced hemolysis. The patient was then worked up for all the possible causes of hemolytic anemia including secondary causes which were all negative except for significant immunoglobulin M mycoplasma levels with elevated cold antibody titers. The patient was then initiated on pulse steroids with azithromycin and doxycycline and hemoglobin levels stabilized. The patient also developed pulmonary thromboembolism which was managed with anticoagulation. The patient made a steady improvement, was discharged, and is on follow-up. Here, we present a unique case of mycoplasma associated cold agglutinin disease causing arterial thrombosis.

Absence of Association between Previous Mycoplasma pneumoniae Infection and Subsequent Myasthenia Gravis: A Nationwide Population-Based Matched Cohort Study

Mycoplasma pneumoniae (M. pneumoniae) is not only one of the most common pathogenic bacteria for respiratory infection but also a trigger for many autoimmune diseases. Its infection process shared many similarities with the pathogenesis of myasthenia gravis (MG) at cellular and cytokine levels. Recent case reports demonstrated patients present with MG after M. pneumoniae infection. However, no epidemiological studies ever looked into the association between the two. Our study aimed to investigate the relationship between M. pneumoniae infection and subsequent development of MG. In this population-based retrospective cohort study, the risk of MG was analyzed in patients who were newly diagnosed with M. pneumoniae infection between 2000 and 2013. A total of 2428 M. pneumoniae patients were included and matched with the non-M. pneumoniae control cohort at a 1:4 ratio by age, sex, and index date. Cox proportional hazards regression analysis was applied to analyze the risk of MG development after adjusting for sex, age, and comorbidities, with hazard ratios and 95% confidence intervals. The incidence rates of MG in the non-M. pneumoniae and M. pneumoniae cohorts were 0.96 and 1.97 per 10,000 person-years, respectively. Another case-control study of patients with MG (n = 515) was conducted to analyze the impact of M. pneumoniae on MG occurrence as a sensitivity analysis. The analysis yielded consistent absence of a link between M. pneumoniae and MG. Although previous studies have reported that M. pneumoniae infection and MG may share associated immunologic pathways, we found no statistical significance between M. pneumoniae infection and subsequent development of MG in this study.

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.

Mycoplasmas-Host Interaction: Mechanisms of Inflammation and Association with Cellular Transformation

Mycoplasmas are the smallest and simplest self-replicating prokaryotes. Located everywhere in nature, they are widespread as parasites of humans, mammals, reptiles, fish, arthropods, and plants. They usually exhibiting organ and tissue specificity. Mycoplasmas belong to the class named Mollicutes (mollis = soft and cutis = skin, in Latin), and their small size and absence of a cell wall contribute to distinguish them from other bacteria. Mycoplasma species are found both outside the cells as membrane surface parasites and inside the cells, where they become intracellular residents as "silent parasites". In humans, some Mycoplasma species are found as commensal inhabitants, while others have a significant impact on the cellular metabolism and physiology. Mollicutes lack typical bacterial PAMPs (e.g., lipoteichoic acid, flagellin, and some lipopolysaccharides) and consequently the exact molecular mechanisms of Mycoplasmas' recognition by the cells of the immune system is the subjects of several researches for its pathogenic implications. It is well known that several strains of Mycoplasma suppress the transcriptional activity of p53, resulting in reduced apoptosis of damaged cells. In addition, some Mycoplasmas were reported to have oncogenic potential since they demonstrated not just accumulation of abnormalities but also phenotypic changes of the cells. Aim of this review is to provide an update of the current literature that implicates Mycoplasmas in triggering inflammation and altering critical cellular pathways, thus providing a better insight into potential mechanisms of cellular transformation.

Development of loop-mediated isothermal amplification coupled with nanoparticle-based lateral flow biosensor assay for Mycoplasma pneumoniae detection

Mycoplasma pneumoniae (MP) is one of the most common pathogens causing respiratory tract infection, especially for community-acquired pneumonia (CAP) in school-age children. There was considerable amount of studies on loop-mediated isothermal amplification (LAMP) assay for MP detection. However, the result interpretation of these developed LAMP assays was sophisticated and subjective. Therefore, we developed and evaluated a LAMP coupled with nanoparticle-based lateral flow biosensor (LFB) assay (LAMP-LFB) for simple, reliable, and objective identification of MP (MP-LAMP-LFB). Six primers specific to P1 gene of MP were designed, and the preferred temperature for this assay was confirmed to be 65 °C. The amplification products could be visually interpreted by LFB within 2 min. The MP-LAMP-LFB assay specifically identified DNA templates of MP, and no cross-reactivity with other pathogens was obtained. The limit of the detection for this assay was 600 fg of DNA templates in pure cultures, which was in complete accordance with colorimetric indicator detection and agarose gel electrophoresis analysis. This assay was applied to 209 oropharyngeal swab specimens collected from children with acute respiratory tract infection for clinical evaluation, and compared to real-time PCR detection. Using the LAMP-LFB and real-time PCR assay, the positive rates of MP were 47.8% and 31.6%, respectively. Results suggested that the LAMP-LFB assay displayed high sensitivity compared to real-time PCR method. In summary, LAMP-LFB assay established here was a simple, objective, and sensitive assay for MP detection, which can be widely applied in clinical settings, especially in rural areas.

Mycoplasma pneumoniaeassociated transverse myelitis presenting as asymmetric flaccid paralysis

Acute transverse myelitis is a rare spinal cord inflammatory disorder that manifests as sudden onset of motor, sensory, and autonomic dysfunctions. Here, we report a case of acute transverse myelitis in a 13- year-old boy secondary to Mycoplasma pneumoniae infection. He presented with left facial palsy and contralateral upper extremity weakness without sensory or autonomic changes. The patient was diagnosed with transverse myelitis based on his magnetic resonance imaging findings, although his presentation was mainly motor dysfunction, which is more consistent with acute flaccid paralysis.

Rapid diagnosis of Mycoplasma pneumonia infection by denaturation bubble-mediated strand exchange amplification: comparison with LAMP and real-time PCR

M. pneumoniae infection is often ignored due to its similar clinical symptom with respiratory tract infections caused by bacteria or viruses, and thus leading to misdiagnosis and delayed treatment. It is critical to develop a rapid, sensitive and specific diagnosis method. Denaturation Bubble-mediated Strand Exchange Amplification (SEA) was established, which is an isothermal method with only a primer pair and one Bst DNA polymerase. Notably, colorimetric SEA assay was developed with simple visual readout, making instrument-independent in detection step. The method could detect as low as 1.0 × 10⁴ copies/mL genomic DNA within 60 min. Considering that more than 80% infected patients have 1.0 × 10⁵−1.0 × 10⁷ copies/mL M. pneumonia DNA, SEA is available for the practical diagnosis of M. pneumoniae in clinical specimens. Through comparing 224 sputum specimens, excellent performance of SEA assay with 90.48% sensitivity and 100% specificity relative to real-time PCR was observed. Compared with LAMP, a comparable sensitivity and low false positive rate was observed for SEA method. Therefore, SEA is a promising method for detecting M. pneumoniae directly from clinical specimens, which is especially suitable for point-of-care testing in primary care facilities and resource-limited settings with minimal equipment and technological expertises.

Stroke Associated With Recent Mycoplasma Pneumoniae Infection: A Systematic Review of Clinical Features and Presumed Pathophysiological Mechanisms

Introduction: An association between Mycoplasma pneumoniae (MP) infection and stroke has been described, especially in children. However, current knowledge on this rare potential cause of stroke is scant. The purpose of this systematic review of all published cases was to help better understand the relationships between recent MP infection and ischemic stroke on a clinical, radiological and pathophysiological perspective.

Material and Methods: A PubMed and Embase search was performed in September 2018 to identify all published cases of stroke occurring within 4 weeks after MP infection.

Results: Twenty-eight patients with ischemic stroke associated with MP infection were identified. Median age was 8 years (range: neonate to 57). The middle cerebral artery territory was involved in 25 (89%) patients. Fifteen (54%) patients had at least one arterial occlusion. Elevated D-dimer and/or fibrinogen was reported in 8 (29%) patients. Four patients had transient anticardiolipin IgM antibodies. Cerebrospinal fluid analysis showed pleocytosis in 7/20 (35%) patients (median: 19 leucocytes/μL, range: 10 to 63) and MP PCR was positive in 3/8 (38%) patients. The etiological work-up was considered inconclusive in 25 (89%) patients. Three (11%) patients died during follow-up, all of early respiratory deterioration. Neurological functional outcome was good in 22/27 (81%) patients.

Conclusion: The association between MP infection and ischemic stroke in children and young adults is rare. Underlying pathogenesis might include hypercoagulability and vasculitis. Most patients achieve a favorable recovery. Whether MP infection could be a long-term risk factor for stroke by promoting atherosclerosis is uncertain and deserves further investigation.

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.

Post-Encephalitic Parkinsonism and Sleep Disorder Responsive to Immunological Treatment: A Case Report

We describe a 70-year-old man who, after a viral encephalitis associated with pneumonia, progressively developed a parkinsonism associated with lethargy. Encephalitis manifested with persistent hiccups, seizures and impairment of consciousness. After 2 weeks, the initial neurologic symptoms subsided and the patient progressively developed movement disorders (rigidity and bradykinesia, resistant to L-DOPA), lethargy and behavioral hypersomnia. Magnetic resonance imaging showed thalamic and hippocampal signal abnormalities, immunohistochemistry on a mouse brain substrate revealed serum autoantibodies binding to the brainstem neuropil. Polysomnographic monitoring was consistent with a very severe disruption of sleep: the sleep-wake cycle was fragmented, and the NREM-REM ultradian cycle was irregular. Intravenous immune globulin therapy resulted in the complete reversal of the movement and the sleep disorders. Our observation confirms that parkinsonism and sleep disorders may be consequences of encephalitis, that an immune-mediated pathogenesis is likely, and, consequently, that immunotherapy can be beneficial in these patients. The polysomnographic monitoring suggests that lethargia, rather than a mere hypersomnia, is the result of a combination between sleep disruption and altered motor control.

Clinically mild encephalitis/encephalopathy with a reversible splenial lesion associated with Mycoplasma pneumoniae infection

Background

Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a clinico-radiological syndrome characterized by transient mild symptoms of encephalopathy and a reversible lesion in the splenium of the corpus callosum on magnetic resonance imaging (MRI). It is often triggered by infection. The common pathogens of MERS are viruses, especially influenza virus. However, Mycoplasma pneumoniae (M.pneumoniae) are relatively rare pathogens for MERS.

Case presentation

Here we report two paediatric cases of M.pneumoniae infection-induced MERS. The diagnosis of M.pneumoniae infection was established based on polymerase chain reaction (PCR) and specific serum antibodies (IgM). Both of the two patients presented with mild encephalopathy manifestations and recovered completely within a few days. The initial MRI showed a lesion in the central portion of the splenium of the corpus callosum, which completely resolved on the seventh and eighth day after admission for case 1 and case 2. Lumbar puncture was performed in both patients, which revealed no pleocytosis. In case 1, the patient had hyponatremia, peripheral facial nerve paralysis, and rash. To the best of our knowledge, it is the first MERS case associated with peripheral nerve damage. In case 2, interleukin-6(IL-6) was moderately increased in the cerebrospinal fluid (CSF). It suggested that IL-6 may play a role in the pathogenesis of M.pneumoniae-induced MERS.

Conclusion

Our study enriches the available information on the pathogens of MERS and provides valuable data for better understanding of this syndrome.

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.

Mycoplasma pneumoniae as a trigger for Henoch-Schönlein purpura in children

Mycoplasma pneumoniae is one of the most common causes of respiratory tract infections in children. Extrapulmonary manifestations are seen in up to 25% of infected patients. Extrapulmonary complications are associated with the central nervous system, gastrointestinal tract, skin changes, myocarditis, pericarditis, hemolytic anemia, thrombocytopenia and thrombosis. The majority of extrapulmonary symptoms are associated with skin changes such as exanthematous skin eruptions, erythema nodosum, urticaria, Stevens-Jonson syndrome. M. pneumoniae stimulates production of the interleukins and tumor necrosis factor (TNF) α and can cause vasculitis. Henoch-Schönlein purpura (HSP) is a leucoclastic vasculitis that affects small vessels. Clinical manifestations of HSP include typical rash, arthritis, gastrointestinal and sometimes renal involvement. The main feature in HSP is abnormal IgA deposits in vessel walls. Circulating abnormal glycosylated IgA 1 and IgG antibodies form immune complexes: IgA1-IgG and anti-IgA 1. Immune complexes activate cytokines, parts of complement and influence directly the endothelium. We report cases of three children with Henoch-Schönlein purpura with prolonged and recurrent skin and joint changes. The serological analysis (positive serum IgM) confirmed Mycoplasma pneumoniae infection. Treatment with clarithromycin caused complete regression of disease. We suggest that in the case of prolonged symptoms of vasculitis due to Henoch-Schönlein purpura, Mycoplasma pneumonia infection may be a potential cause of exacerbation of the disease.

Reversible bilateral striatal lesions following Mycoplasma pneumoniae infection associated with elevated levels of interleukins 6 and 8

BACKGROUND

Reversible bilateral striatal necrosis associated with Mycoplasma pneumoniae (M. pneumoniae) infection is a rare neurological disease. The exact pathogenic mechanism remains unknown.

PATIENT

We report reversible bilateral striatal lesions with a favorable outcome secondary to M. pneumoniae infection in an 8-year-old Chinese girl. Cranial MRI showed abnormal signals in bilateral striatum, which disappeared 8 months later. To better understand the pathogenesis of this encephalopathy, we examined cytokines levels in serum and cerebrospinal fluid from this patient. The results revealed the concentrations of interleukin-6 and interleukin-8 increased significantly in serum (26 pg/mL and 66 pg/mL, respectively) and cerebrospinal fluid (122 pg/mL and 325 pg/mL, respectively), and were reduced markedly after the therapy. Intrathecal production of interleukin-6 and interleukin-8 is probably related to the pathogenesis of striatal lesions caused by M. pneumoniae. These cytokines may cause local vascular injury, and finally leading to local vascular occlusion.

CONCLUSION

Our results suggest that interleukin-6 and interleukin-8 may play important roles in the pathogenesis of this disease. This is the first report to describe the role of cytokines in this condition and relevant literature is reviewed. Our findings may lead to better understanding of the pathogenesis of M. pneumoniae-associated striatal lesions.

A New Observation of an Atypical and Severe Variant of the Guillain-Barre Syndrome in a Child: Remaining Challenges for Diagnosis, Nosologic Classification, and Therapeutic Course

Guillain-Barré syndrome is a rare acute polyradiculoneuropathy. Several variants and unusual presentations have been described, particularly in pediatrics. In most cases, making an early diagnosis is challenging due to the treatments that consist in the rapid administration of intravenous immunoglobulin or plasma exchange. The authors present the case of a 7-year-old boy with an atypical and severe axonal Guillain-Barré syndrome, associated with Mycoplasma pneumonia. When he was admitted, febrile respiratory failure was the main focus, and then he presented signs of acute polyneuropathy with cranial nerve palsy and brief hyperreflexia. Mechanical ventilation was required for 48 days as well as 2 cycles of intravenous immunoglobulin. The authors describe all the medical challenges that the authors encountered. This case highlights the fact that respiratory distress can be the main clinical symptom in children. This delays the establishment of a correct diagnosis, even more so when neurological manifestations are abundant and unusual.

[Neurological symptoms due to Mycoplasma pneumoniae infection in nine children]

Mycoplasma pneumoniae infection is common in children. Extrapulmonary symptoms usually reveal as neurological symptoms, mainly as encephalitis with significant morbidity and mortality. Various other neurological presentations have also been reported. We describe a cohort of nine children with neurological manifestations due to M. pneumoniae infection, including five cases of encephalitis, one of polyradiculoneuritis, one of ophthalmoplegia, one of optic neuritis, and one of myositis. Progression was variable from ad integrum recovery to severe brain damage. Diagnosis is usually confirmed by PCR and/or serological follow-up, but the latter is still insufficiently used in practice to systematically affirm the diagnosis. Therapeutic management is not clearly defined and long-term progression can be uncertain despite early antibiotic and/or anti-inflammatory treatments.

Disordered eating and food restrictions in children with PANDAS/PANS

OBJECTIVE

Sudden onset clinically significant eating restrictions are a defining feature of the clinical presentation of some of the cases of pediatric acute-onset neuropsychiatric syndrome (PANS). Restrictions in food intake are typically fueled by contamination fears; fears of choking, vomiting, or swallowing; and/or sensory issues, such as texture, taste, or olfactory concerns. However, body image distortions may also be present. We investigate the clinical presentation of PANS disordered eating and compare it with that of other eating disorders.

METHODS

We describe 29 patients who met diagnostic criteria for PANS. Most also exhibited evidence that the symptoms might be sequelae of infections with Group A streptococcal bacteria (the pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections [PANDAS] subgroup of PANS).

RESULTS

The clinical presentations are remarkable for a male predominance (2:1 M:F), young age of the affected children (mean=9 years; range 5-12 years), acuity of symptom onset, and comorbid neuropsychiatric symptoms.

CONCLUSIONS

The food refusal associated with PANS is compared with symptoms listed for the new Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-V) diagnosis of avoidant/restrictive food intake disorder (ARFID). Treatment implications are discussed, as well as directions for further research.

Infektionen

In diesem Kapitel werden zunächst die für die Neurointensivmedizin wesentlichen bakteriellen Infektionen (Meningitis, spinale und Hirnabszesse, Spondylodiszitis, septisch-embolische Herdenzephalitis) abgehandelt, die trotz gezielt eingesetzter Antibiotika und neurochirurgischer Therapieoptionen noch mit einer erheblichen Morbidität und Mortalität behaftet sind. Besonderheiten wie neurovaskuläre Komplikationen, die Tuberkulose des Nervensystems, Neuroborreliose, Neurosyphilis und opportunistische Infektionen bei Immunsuppressionszuständen finden hierbei besondere Berücksichtigung. Der zweite Teil dieses Kapitels behandelt akute und chronische Virusinfektionen des ZNS sowie in einem gesonderten Abschnitt die HIVInfektion und HIV-assoziierte Krankheitsbilder sowie Parasitosen und Pilzinfektionen, die in Industrieländern seit Einführung der HAART bei HIV zwar eher seltener, aber mit zunehmender Globalisierung auch in unseren Breiten immer noch anzutreffen sind.

Pediatric acute-onset neuropsychiatric syndrome

Whether some instances of obsessive-compulsive disorder are secondary to infectious and/or autoimmune processes is still under scientific debate. The nosology has undergone an iterative process of criteria and acronyms from PITANDS to PANDAS to PANS (or CANS for neurology). This review focuses on the clinical presentation, assessment, proposed pathophysiology, and treatment of pediatric autoimmune neuropsychiatric disorders associated with streptococcus (PANDAS), and the newest iteration, pediatric acute-onset neuropsychiatric syndrome (PANS). Children who have these symptoms, which have become known as PANS, have been described by their parents as "changed children."

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.

Expanding the spectrum of MERS type 2 lesions, a particular form of encephalitis

We report on a 13-year-old boy who presented with signs suggestive of encephalitis and in whom magnetic resonance imaging revealed lesions in the genu and splenium of the corpus callosum and symmetrical lesions bilaterally in the center semiovale. This clinical-radiologic entity was previously reported in the literature and was given the acronym MERS type 2 (mild encephalitis with reversible splenial) lesion. The clinical, radiologic, and biochemical characteristics of the patient with MERS type 2 lesions presented in this article show some differences with those in previously reported patients. His clinical recovery was particularly slow, cerebrospinal fluid was abnormal, and on magnetic resonance imaging the typical time course of MERS type 2 lesions resolving through a phase of solitary lesions in the splenium of the corpus callosum, the so-called type 1 lesions, was not seen. He is also the first patient in whom mycoplasma pneumoniae was found to be associated with MERS type 2 lesions. These findings further expand the spectrum of MERS type 2 lesions. The question raises whether the MERS type 2 lesion represents a new type of encephalitis or a particular radiologically recognizable subtype of postinfectious encephalitis. In the article, previously reported patients with MERS type 2 lesions are reviewed.

Infektionen

Trotz Weiterentwicklung moderner Antibiotika in den letzten Jahren sind die Letalitätszahlen der bakteriellen (eitrigen) Meningitis weiterhin hoch; Überlebende haben häufig neurologische Residuen. Die ungünstigen klinischen Verläufe der bakteriellen Meningitis sind meist Folge intrakranieller Komplikationen, wie z. B. eines generalisierten Hirnödems, einer zerebrovaskulären arteriellen oder venösen Beteiligung oder eines Hydrozephalus.

Neurologic infectious disease emergencies

Nearly 70 years after the discovery of penicillin, neurologic infectious diseases (NIDs) remain an important worldwide source of morbidity and mortality. The clinician faced with a potential NID must urgently consider patient demographics, pace of illness and clinical syndrome, and laboratory data. In keeping with the topics of this issue, initial emergency diagnosis and management are emphasized, with appropriate references to relevant literature for subsequent longer-term interventions.

Mycoplasma pneumoniae-related postencephalitic epilepsy in children

PURPOSE

Mycoplasma pneumoniae, a common respiratory pathogen, has been implicated as an etiology of encephalitis, but there are few reports about it and postencephalitic epilepsy. This study aimed to investigate clinical factors, electroencephalography, and neuroradiologic features of M. pneumoniae-related encephalitis in a series of children with postencephalitic epilepsy and to examine possible prognostic factors.

METHODS

Cases of M. pneumoniae-related encephalitis between January 2001 and June 2010 were retrospectively reviewed. Systematic clinical data were evaluated.

KEY FINDINGS

The 99 enrolled patients with M. pneumoniae-related encephalitis were all positive by serology and 47 (47.5%) of them developed postencephalitic epilepsy. During the acute phase, 53 patients (53.5%) had seizures, the most common type of which was primary focal with secondary generalized tonic-clonic seizure (39.6%). The most common initial electroencephalography was focal/diffuse cortical dysfunction (37.4%) and focal epileptiform discharge (26.4%). The time of follow-up ranged from 6-131 months. At the end of the study, 19 (40.4%) of the 47 children with postencephalitic epilepsy had intractable seizures.

SIGNIFICANCE

Postencephalitic epilepsy is not a rare complication of M. pneumoniae-related encephalitis. Seizures in the acute phase and focal epileptiform discharges in initial electroencephalography are significant prognostic factors.

Complete resolution of advanced Mycoplasma pneumoniae encephalitis mimicking brain mass lesions: report of two pediatric cases and review of literature

Mycoplasma pneumoniae is a well-known cause of atypical pneumonia. CNS involvement is a relatively frequent extrapulmonary manifestation, most commonly manifesting as encephalitis in the pediatric population. We present two unusual cases of M. pneumoniae encephalitis that presented with symptoms and imaging findings suggesting mass occupying lesions, and worsening altered mental status. Biopsy of the lesions was necessary in both cases to aid with diagnosis. Histopathologic features excluded neoplasm, and established the diagnosis of encephalitis, but did not point toward its etiology. The only finding that indicated M. pneumoniae as the most likely pathogen was serum IgM positivity in the absence of any other identifiable infectious source, and complete neurologic recovery following specific anti-mycoplasmal treatment. The patients were successfully treated with antibiotics and steroids, with the second case also requiring intravenous immunoglobulin and anti-epileptics. The clinical presentation and histopathologic findings suggested an immune-mediated pathogenesis, but acute disseminated encephalomyelitis was excluded due to extensive gray matter involvement. Disease resolution despite status epilepticus and herniation in case 2 is a novel finding of the study. Current principles of diagnosis and management of encephalitis as the presenting manifestation of mycoplasmal infection are discussed.

Constrictive pericarditis secondary to infection with Mycoplasma pneumoniae

Pericardial effusions can be insidious, variable in presentation, and may result from a wide variety of causes. We report here a rare case of pericardial effusion in a pediatric patient secondary to infection with Mycoplasma pneumoniae that progressed to cardiac tamponade and constrictive pericarditis. The differential diagnosis of pericardial effusion is reviewed as well as current treatments for pericardial effusions and constrictive pericarditis.

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.

Transverse myelitis as a rare, serious complication of Mycoplasma pneumoniae infection

We report on the first published case of a Mycoplasma pneumoniae-associated transverse myelitis appearing in childhood and leading to persistent paraplegia and bowel and bladder dysfunctions. Magnetic resonance imaging of the spinal cord indicated extensive transverse myelitis extending from T(5)-T(12). A repeated scan established spinal cord atrophy in the affected area. Various therapies (methylprednisolone pulse therapy, plasmapheresis, and roxythromycine) produced no clinical effect.

Pathogenesis of neurologic manifestations of Mycoplasma pneumoniae infection

Mycoplasma pneumoniae has been associated with various neurologic manifestations, but exactly how the organism can cause such a wide variety of diseases is a long-standing mystery. In this respect, although pneumonia has been considered the hallmark of Mycoplasma pneumoniae infection, emerging accumulations of data have revealed that the infection can cause a number of extrapulmonary manifestations even in the absence of pneumonia. The importance of host immune response in the pathomechanism of pneumonia has been established, but the pathomechanisms of extrapulmonary manifestations remain largely unknown. For this review, extrapulmonary manifestations due to M. pneumoniae infection were classified into three categories: a direct type, in which locally induced cytokines must play a role; an indirect type, in which immune modulation such as autoimmunity must play a role; and a vascular occlusion type, in which vasculitis or thrombosis (either or both, and with or without systemic hypercoagulable state) must play a role. This classification was then applied within a literature review for neurologic manifestations. Most neurologic manifestations due to M. pneumoniae infection could be reasonably classified into and explained by one of the three types of pathomechanisms.