Outbreak of Mycoplasma pneumoniae-Associated Stevens-Johnson Syndrome

Predicting the impact of non-pharmaceutical interventions against COVID-19 on Mycoplasma pneumoniae in the United States

The introduction of non-pharmaceutical interventions (NPIs) against COVID-19 disrupted circulation of many respiratory pathogens and eventually caused large, delayed outbreaks, owing to the build up of the susceptible pool during the intervention period. In contrast to other common respiratory pathogens that re-emerged soon after the NPIs were lifted, longer delays (> 3 years) in the outbreaks of Mycoplasma pneumoniae (Mp), a bacterium commonly responsible for respiratory infections and pneumonia, have been reported in Europe and Asia. As Mp cases are continuing to increase in the US, predicting the size of an imminent outbreak is timely for public health agencies and decision makers. Here, we use simple mathematical models to provide robust predictions about a large Mp outbreak ongoing in the US. Our model further illustrates that NPIs and waning immunity are important factors in driving long delays in epidemic resurgence.

Metagenomic next-generation sequencing of bronchoalveolar lavage fluid in non-severe and severe pneumonia patients

Metagenomic next-generation sequencing (mNGS) is widely used as a more promising technology than conventional tests. However, its clinical utility in the context of bronchoalveolar lavage fluid (BALF) samples for discriminating between non-severe and severe pneumonia is not well established. Thus, this study aimed to investigate the diagnostic performance of mNGS on BALF samples from 100 individuals suspected of pneumonia, and compared it with conventional microbiological tests (CMT) of BALF samples and the final clinical diagnosis. Twenty-seven cases of non-severe pneumonia and 73 cases of severe pneumonia patients were finally clinically diagnosed. Among 100 cases, diagnostic performance of mNGS and culture showed a significant difference; 65 cases had the same sample types, of which 25 cases were diagnosed as positive by mNGS only (38.46%) and 1 was diagnosed as positive by culture only (1.54%). Moreover, 24 cases were diagnosed positive in both mNGS and culture (36.92%) and 15 cases tested negative in both mNGS and culture (23.08%). Among 35 cases, 28 out of 35 cases were diagnosed as positive by mNGS, while only 4 out of 35 cases were diagnosed as positive by the indirect immunofluorescence method (IIFT). In addition, the positive rate of mNGS was higher than that of culture in cases regardless of prior antibiotic exposure. Mixed pathogens were found to be significantly more prevalent in severe pneumonia patients than in non-severe pneumonia patients. Importantly, among 38 cases who were diagnosed solely by mNGS, 25 patients experienced an improved outcome after physicians changed the therapy according to the mNGS results. In conclusion, the results showed that mNGS of BALF represents a potentially effective tool for detection of mixed pathogens in severe pneumonia.

Ocular Manifestations and Outcomes in Children With Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Comparison With Adult Patients

PURPOSE

To compare the clinical features and visual outcomes in children and adults with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).

DESIGN

Retrospective comparative case series.

METHODS

This retrospective study included 280 eyes of 140 patients (35 children and 105 adults) with SJS/TEN treated between 2010 and 2020. The primary outcome measures were the final best-corrected visual acuity (BCVA) and severity of dry eye. The secondary outcome measure was the medical and surgical therapies used.

RESULTS

Among 64 eyes of children recruited in the study, acute ocular involvement was found in 58 eyes (90.6%). The chronic score in pediatric patients was significantly higher than that in adult patients (P = .004). The use of antibiotics/nonsteroidal anti-inflammatory drugs (NSAIDs) and Mycoplasma infection were the more common etiologies in children. In all, 75% of eyes in children maintained a visual acuity of 20/40 or better at a mean follow-up time of 4.3 years. The severity of dryness was comparable between the child and adult groups. The proportion of eyes undergoing amniotic membrane and oral mucosa transplantation was significantly higher in children than in adults in the chronic stage, reflecting that children exhibit much more severe complications.

CONCLUSIONS

Although pediatric SJS/TEN patients have more severe ocular complications than adults, most children maintain long-term good vision. Early intervention and aggressive treatment help to preserve vision.

A CRISPR-Cas12a-Based platform for ultrasensitive, rapid, and highly specific detection of Mycoplasma pneumonia in clinical application

Mycoplasma pneumoniae (MP), which is responsible for a majority of community-acquired pneumonia (CAP) in children, has been largely underestimated. Here, we coupled multiple cross displacement amplification (MCDA) technique with CRISPR-Cas12a-based biosensing system to design a novel detection platform termed MP-MCDA-CRISPR assay for MP infection diagnosis and clinical application. The MP-MCDA-CRISPR assay amplified the CARDS gene of MP by MCDA method, followed by trans-cleavage of the reporter molecular upon the formation of CRISPR-Cas12a-gRNA-target DNA complex, which was confirmed by the release of fluorescent signals. A set of standard MCDA primers, an engineered CP1 primer, a quenched fluorescent ssDNA reporter, and a gRNA were designed targeting the CARDS gene of MP. The optimal temperature for MCDA pre-amplification is 64°C, and the time for CRISPR-Cas12a-gRNA biosensing process is 5 min. The limit of detection (LoD) of the MP-MCDA-CRISPR assay is 50 fg per reaction without any cross-reaction with other non-MP pathogens. The MP-MCDA-CRISPR assay accurately identified the 50 real time-PCR positive clinical samples and 78 negative ones. Taken together, the MP-MCDA-CRISPR assay designed here is a promising diagnostic tool for point-of care (POC) testing of MP infection.

Bronchiolitis obliterans associated with toxic epidermal necrolysis induced by infection: A case report and literature review

Background

Stevens-Johnson syndrome/toxic epidermal necrolysis has a severe impact on patients' eyes, genital mucosa, and many other organs. Bronchiolitis obliterans is a rare complication of Stevens-Johnson syndrome/toxic epidermal necrolysis.

Data sources

We report a case of bronchiolitis obliterans associated with toxic epidermal necrolysis in our department. Furthermore, we examined the patients with bronchiolitis obliterans induced by Stevens-Johnson syndrome/toxic epidermal necrolysis and summarized the clinical characteristics, treatment, and prognosis. Databases available online in English including PubMed, Medline, and Web of Science were consulted.

Results

We report one case and review 23 published case reports. Of the 24 patients, 13 were female, the oldest patient was 59 years old and the youngest was 5 years old. The time of bronchiolitis obliterans onset after Stevens-Johnson syndrome/toxic epidermal necrolysis varied from 5 days to 5 months. Bronchoscopy examination showed ulceration, exudative lesions, occlusion, and inflammation. The CT of lung manifestation included mosaic perfusion, bronchiectasis, consolidation, air trapping, pneumatocele, pleural thickening, lung collapse, larger central airway dilatation, lung overinflation, oligemia, and pneumomediastinum. Most cases indicated pulmonary function tests with obstructive ventilation dysfunction. The prognosis was poor; six of the patients died.

Conclusions

Patients with Stevens-Johnson syndrome/toxic epidermal necrolysis may develop bronchitis obliterans at different stages, so all patients with Stevens-Johnson syndrome/toxic epidermal necrolysis should be followed up for possible respiratory complications.

The role of flexible bronchoscopy in children with Mycoplasma pneumoniae pneumonia

PURPOSE

To explore the effectiveness of flexible bronchoscopy in pediatric Mycoplasma pneumoniae pneumonia (MPP).

METHODS

This retrospective cohort study included children with MPP admitted between 2016 and 2019 in Shanghai. Tracheobronchial manifestations, etiologic findings, therapeutic effect, and health-economic indicators were assessed in bronchoscopy (plus bronchoalveolar lavage (BAL)) and non-bronchoscopy group. We used propensity-score matching and multivariable logistic regression to investigate the effect of bronchoscopy and BAL on disease recovery.

RESULTS

In 900 children with MPP, 24/278 (8.6%) of those who underwent bronchoscopy had sputum plugs. Coinfection rate was four-fold enhanced by BAL (19.6% vs. 4.5%, p < 0.01) in patients with severe MPP (SMPP) and nearly doubled (10.8% vs. 5.9%, p = 0.03) in those without SMPP, compared with no BAL. Total of 224 (24.9%) patients had multilobar consolidation; after BAL, a significantly shorter lesion-resolution duration was observed on imaging (OR: 0.2, 95% CI: 0.0-0.7). However, longer fever duration (OR: 2.8, 95% CI: 1.7-4.8), hospital stay (OR: 3.1, 95% CI: 1.9-5.1), and higher costs were found in the bronchoscopy group than in the non-bronchoscopy group.

CONCLUSIONS

Through BAL, coinfection may explain one-fifth of causes for SMPP. Bronchoscopy with BAL may increase the detection rate of pathogen and resolve pulmonary lesions in patients with multilobar consolidation.

IMPACT

Flexible bronchoscopy with bronchoalveolar lavage is of great assistance in the timely detection of coinfection, sputum plug and inflammatory polyps in children with Mycoplasma pneumoniae pneumonia (MPP), and improves the recovery of lung damage in MPP patients with multilobar consolidation. This study provides new insights into the indications of flexible bronchoscopy for the diagnosis and treatment of pediatric patients with MPP.

Tools to improve the diagnosis and management of T-cell mediated adverse drug reactions

Delayed drug T-cell immune-mediated hypersensitivity reactions have a large clinical heterogeneity varying from mild maculopapular exanthema (MPE) to severe cutaneous adverse reactions (SCARs) such as acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS) and severe skin necrosis and blistering as seen in Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Given the knowledge gaps related to the immunopathogenesis of these conditions, the absence of validated diagnostic tools and the significant associated morbidity and mortality, patients with SCARs often have limited drug choices. We performed a comprehensive review aiming to evaluate in vivo diagnostic tools such as delayed intradermal skin and patch testing and ex vivo/in vitro research assays such as the lymphocyte transformation test (LTT) and the enzyme-linked ImmunoSpot (ELISpot) assay. We searched through PubMed using the terms “drug allergy,” “in vivo” and “ex vivo” for original papers in the last 10 years. A detailed meticulous approach adapted to the various clinical phenotypes is recommended for the diagnostic and management of delayed drug hypersensitivity reactions. This review highlights the current diagnostic tools for the delayed drug hypersensitivity phenotypes.

Mycoplasma pneumoniae-Induced Rash and Mucositis (MIRM) Mimicking Behçet’s Disease and Paraneoplastic Pemphigus (PNP)

MIRM is an uncommon entity characterized by prominent mucositis, usually with sparse cutaneous involvement. The diagnosis of MIRM can be challenging due to the lack of awareness amongst clinicians. Patients with Behçet's disease usually present with recurrent and painful mucocutaneous ulcers, while other clinical manifestations of the disease are more variable. Here, we describe an interesting case of MIRM mimicking Behçet's disease and PNP highlighting the overlapping manifestations and diagnostic challenges.

Stevens-Johnson syndrome in children

PURPOSE OF REVIEW

The concept of Stevens-Johnson syndrome (SJS) in children is evolving. This manuscript reviews recent advances with the lens of new terminology namely infection-triggered reactive infectious mucocutaneous eruption and drug-induced epidermal necrolysis, with the objective of integrating this novel terminology practically.

RECENT FINDINGS

Traditionally considered to exist on a spectrum with toxic epidermal necrolysis, SJS in children is more often caused or triggered by infections instead of medications. Proposed pediatric-specific terminology can be applied to literature to gain further insights into blistering severe cutaneous adverse reactions.

SUMMARY

Distinguishing infection-triggered from drug-triggered blistering reactions is useful for 3 main reasons: (1) early clinically recognizable different features such as isolated or predominant mucositis, (2) different initial management depending on trigger, (3) avoiding the label of a drug reaction on cases triggered by infection.

Molecular Tools for Typing Mycoplasma pneumoniae and Mycoplasma genitalium

Mycoplasma pneumoniae and Mycoplasma genitalium are cell wall-less bacteria with strongly reduced genome content and close phylogenetic relatedness. In humans, the only known natural host, the microorganisms colonize the respiratory or genitourinary mucosa and may cause a broad range of clinical presentations. Besides fundamental differences in their tissue specificity, transmission route, and ability to cause prevalence peaks, both species share similarities such as the occurrence of asymptomatic carriers, preferred populations for infection, and problems with high rates of antimicrobial resistance. To further understand the epidemiology of these practically challenging bacteria, typing of strains is necessary. Since the cultivation of both pathogens is difficult and not performed outside of specialized laboratories, molecular typing methods with adequate discriminatory power, stability, and reproducibility have been developed. These include the characterization of genes containing repetitive sequences, of variable genome regions without the presence of repetitive sequences, determination of single and multi-locus variable-number tandem repeats, and detection of single nucleotide polymorphisms in different genes, respectively. The current repertoire of procedures allows reliable differentiation of strains circulating in different populations and in different time periods as well as comparison of strains occurring subsequently in individual patients. In this review, the methods for typing M. pneumoniae and M. genitalium, including the results of their application in different studies, are summarized and current knowledge regarding the association of typing data with the clinical characteristics of infections is presented.

[Viral exanthems in children]

Virale und paravirale Exantheme sind die häufigsten Exantheme des Kindesalters, die auch meist zu einer Vorstellung in der Praxis inklusive der Notaufnahme führen. Die Kenntnis der verschiedenen Krankheitsbilder ist entscheidend für die adäquate Diagnostik und Betreuung der kleinen Patient:innen, die entsprechende Aufklärung der Familie und ggf. das Minimieren des Infektionsrisikos. In der aktuellen Arbeit werden die kürzlich beschriebenen „reactive infectious mucocutaneous eruptions“ (RIME) und das „pediatric inflammatory multisystem syndrome“ (PIMS) vorgestellt. Zusätzlich werden wir einige atypische Manifestationen des Gianotti-Crosti-Syndroms und der Hand-Fuß-Mund-Erkrankung – wie z. B. die mit Mollusken assoziierte „Gianotti-Crosti-like reaction“ und das „eczema coxsackium“ – erläutern.

Chronic Spontaneous and Inducible Urticaria Associated With Mycoplasma pneumoniae Infection

Acute childhood urticaria is a common disorder that has been associated with infections. In a few children, it may last for more than six weeks, thereafter it is characterized as chronic urticaria (CU). We report two cases, one suffering from chronic spontaneous urticaria and one chronic inducible urticarias (dermographism and cold urticaria). Both children had concomitant respiratory symptoms that were associated with Mycoplasma pneumoniae (MP) infection. Urticarias' symptoms and signs were refractory to regular antihistamines dose but showed marked improvement or complete resolution following clarithromycin administration. CU response to antibiotics pointed strongly to a potential causative role of MP in the pathogenesis of chronic spontaneous and chronic inducible urticarias. It is not clear if MP was the etiopathogenic cause or just the trigger. Nevertheless, refractory to antihistamines urticarias associated with MP infection may respond to antibiotics, which should be considered as an alternative therapeutic approach.

Mycoplasma pneumoniae Genotypes and Clinical Outcome in Children

Factors leading to the wide range of manifestations associated with Mycoplasma pneumoniae infection are unclear. We investigated whether M. pneumoniae genotypes are associated with specific clinical outcomes. We compared M. pneumoniae loads and genotypes of children with mucocutaneous disease to those of children with pneumonia, family members with upper respiratory tract infection (URTI), and carriers from a prospective cohort study (n = 47; 2016 to 2017) and to those of other children with mucocutaneous disease from a case series (n = 7; 2017 to 2020). Genotyping was performed using macrolide resistance determination, P1 subtyping, multilocus variable-number tandem-repeat analysis (MLVA), and multilocus sequence typing (MLST). Comparisons were performed with a pairwise Wilcoxon rank sum test and a Fisher exact test with corrections for multiple testing, as appropriate. M. pneumoniae loads did not statistically differ between patients with mucocutaneous disease and those with pneumonia or carriers. Macrolide resistance was detected in 1 (1.9%) patient with mucocutaneous disease. MLVA types from 2016 to 2017 included 3-5-6-2 (n = 21 [46.7%]), 3-6-6-2 (n = 2 [4.4%]), 4-5-7-2 (n = 14 [31.1%]), and 4-5-7-3 (n = 8 [17.8%]), and they correlated with P1 subtypes and MLST types. MLVA types were not associated with specific outcomes such as mucocutaneous disease, pneumonia, URTI, or carriage. They were almost identical within families but varied over geographic location. MLVA types in patients with mucocutaneous disease differed between 2016 to 2017 (3-5-6-2, n = 5 [62.5%]) and 2017 to 2020 (4-5-7-2, n = 5 [71.4%]) (P = 0.02). Our results suggest that M. pneumoniae genotypes may not determine specific clinical outcomes.

Associations Between Stevens-Johnson Syndrome and Infection: Overview of Pharmacoepidemiological Studies

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are classified as type B adverse drug reactions, and are severe, potentially fatal rare disorders. However, the pathogenesis of SJS/TEN is not fully understood. The onset of SJS/TEN is triggered by the immune system in response to antigens with or by drugs. As activation of the immune system is important, infection could be a risk factor for the onset of SJS/TEN. Based on the hypothesis that infections induce the onset of SJS/TEN, we conducted pharmacoepidemiological investigations using two spontaneous adverse drug reaction reporting databases (Japanese Adverse Drug Event Report database and Food and Drug Administration Adverse Event Reporting System) and Japanese medical information database. These data suggest that infection could be a risk factor for the development of SJS/TEN. In this mini-review, we discuss the association between infection and the development of SJS/TEN.

Rash and Mucositis Associated With Mycoplasma pneumoniae and Chlamydophila pneumoniae: A Recurrence of MIRM?

INTRODUCTION

A new concept has come to light recently, that is, Mycoplasma-induced rash and mucositis (MIRM). Here, we report the first case of recurrent rash, mucositis, and conjunctivitis involving Mycoplasma pneumoniae and C. pneumoniae that fits under the criteria of what is currently defined as MIRM.

CASE PRESENTATION

A patient aged 12 years with a history of recurrent aphthous ulcers presented in 2013 with worsening oral lesions, conjunctivitis, and vesicular rash. Her respiratory polymerase chain reaction (PCR) panel was positive for M. pneumoniae. She was diagnosed with Stevens-Johnson syndrome (SJS) secondary to M. pneumoniae and treated with a macrolide, acyclovir, and intravenous immunoglobulin (IVIG). The same patient returned 3 years later with an identical constellation of symptoms, at which time her PCR was positive for C. pneumoniae. In addition to IVIG and a macrolide, a corticosteroid treatment was administered.

DISCUSSION

Here, we present the case of a pediatric patient with a recurrence of mucocutaneous disease that is more consistent with MIRM than the proposed SJS or erythema multiforme (EM) documented via histology. Our patient's symptoms were controlled with azithromycin and IVIG and, in the second episode, with corticosteroids as well. This case adds to that of Mayor-Ibarguren et al, providing further evidence that C. pneumonia may also be a trigger for MIRM. Patients will benefit from expanding the definition of MIRM, as the pathogenesis differs from SJS and EM and could result in more specific treatment options.

Mycoplasma pneumoniae pneumonia with pulmonary embolism: A study on pediatric cases in Jilin province of China

Mycoplasma is one of the most common pathogens causing community-acquired pneumonia in pediatric patients. In recent years, the number of refractory or severe cases with drug resistance has been gradually increasing and cases that developed embolism after Mycoplasma pneumoniae (M. pneumoniae) infection have been reported. The present study retrospectively analyzed the clinical features, diagnosis and treatment of M. pneumoniae pneumonia (MPP) combined with pulmonary embolism (PE) in a series of 7 cases encountered between January 1st, 2016 to August 1st, 2019 at the Department of Pediatric Intensive Care Unit of The First Hospital of Jilin University (Changchun, China). Combined with relevant Chinese and international studies published during the last two decades, a comprehensive analysis was performed. All of the pediatric patients of the present study had fever, cough and dyspnea respiratory symptoms at onset and the disease progressed rapidly. Thereafter, PE was confirmed by a series of examinations. Pulmonary CT indicated patchy inflammations and significantly elevated D-dimer levels, accompanied by positive anticardiolipin antibodies. Furthermore, a filling defect in the pulmonary artery branch was observed on CT pulmonary angiography (CTPA) examination. In 2 cases, the condition was improved with anti-infection and anticoagulation treatment with low-molecular-weight heparin and warfarin, respectively, and the pulmonary embolism disappeared after 3-4 months. A total of 5 cases, who were not responsive to the drug treatment, underwent surgical resection. During the operation, the local tissues were determined to be infarcted and the pathological diagnosis was consistent with pulmonary infarction. Among the 5 cases, 2 died of Acute Respiratory Distress Syndrome at 3-8 days after the operation. The remaining patients underwent 6-12 months of follow-up and respiratory rehabilitation and their quality of life is now good. In conclusion, compared with healthy individuals, pediatric patients with critical MPP have an elevated risk of embolism. It is necessary to be vigilant regarding whether MMP is combined with PE and perform timely CTPA examination. Early detection, early treatment and surgical intervention (if necessary) may significantly reduce the risk of mortality and disability.

Frequency and Clinical Presentation of Mucocutaneous Disease Due to Mycoplasma pneumoniae Infection in Children With Community-Acquired Pneumonia

Importance

The diagnosis of Mycoplasma pneumoniae infection as the cause of mucocutaneous disease is challenging because current diagnostic tests are not able to differentiate M pneumoniae infection from carriage.

Objective

To examine the frequency and clinical presentation of M pneumoniae-induced mucocutaneous disease in children with community-acquired pneumonia (CAP) using improved diagnostics.

Design, Setting, and Participants

This prospective, longitudinal cohort study included 152 children aged 3 to 18 years with CAP enrolled in a CAP study from May 1, 2016, to April 30, 2017, at the University Children's Hospital Zurich. Children were inpatients or outpatients with clinically defined CAP according to the British Thoracic Society guidelines. Data analysis was performed from July 10, 2017, to June 29, 2018.

Main Outcomes and Measures

Frequency and clinical presentation of M pneumoniae-induced mucocutaneous disease in childhood CAP. Mycoplasma pneumoniae infection was diagnosed by polymerase chain reaction (PCR) of oropharyngeal samples and confirmed with the measurement of specific peripheral blood IgM antibody-secreting cells by enzyme-linked immunospot assay to differentiate M pneumoniae-infected patients from carriers with CAP caused by other pathogens. Mucocutaneous disease was defined as any eruptive lesion that involved skin and/or mucous membranes occurring during the CAP episode.

Results

Among 152 enrolled children with CAP (median [interquartile range] age, 5.7 [4.3-8.9] years; 84 [55.3%] male), 44 (28.9%) tested positive for M pneumoniae by PCR; of these, 10 children (22.7%) developed mucocutaneous lesions. All 10 patients with mucocutaneous eruptions tested positive for specific IgM antibody-secreting cells. Skin manifestations were found in 3 cases (2.8%) of M pneumoniae PCR-negative CAP (P < .001). The spectrum of M pneumoniae-induced mucocutaneous disease included M pneumoniae-induced rash and mucositis (3 cases [6.8%]), urticaria (2 cases [4.5%]), and maculopapular skin eruptions (5 cases [11.4%]). Two patients had ocular involvement as the sole mucosal manifestation (bilateral anterior uveitis and nonpurulent conjunctivitis). Patients with M pneumoniae-induced mucocutaneous disease had longer duration of prodromal fever (median [interquartile range], 10.5 [8.3-11.8] vs 7.0 [5.5-9.5] days; P = .02) and higher C-reactive protein levels (median [interquartile range], 31 [22-59] vs 16 [7-23] mg/L; P = .04) than patients with CAP due to M pneumoniae without mucocutaneous manifestations. They were also more likely to require oxygen (5 [50%] vs 1 [5%]; P = .007), to require hospitalization (7 [70%] vs 4 [19%]; P = .01), and to develop long-term sequelae (3 [30%] vs 0; P = .03).

Conclusions and Relevance

Mucocutaneous disease occurred significantly more frequently in children with CAP due to M pneumoniae than in children with CAP of other origins. Mycoplasma pneumoniae-induced mucocutaneous disease was associated with increased systemic inflammation, morbidity, and a higher risk of long-term sequelae.

Reactive infectious mucocutaneous eruption: Mycoplasma pneumoniae-induced rash and mucositis and other parainfectious eruptions

Mycoplasma pneumoniae-induced rash and mucositis is the most accurate diagnosis for patients with blistering mucocutaneous disease provoked by an infection. Recent literature suggests expansion of the name is required, as other infections have caused a clinically similar presentation. This review provides a concise update on current understanding of M. pneumoniae-induced rash and mucositis and other reactive infectious mucocutaneous eruptions.

Stevens-Johnson Syndrome Due to Influenza Vaccination

Influenza is a common virus that affects millions of people every year. The influenza vaccine decreases morbidity and mortality associated with influenza and is generally well tolerated. Stevens-Johnson syndrome (SJS) is a rare disorder of the skin and mucous membranes. We report the second known case of SJS occurring after an influenza vaccination alone without any other associated drug exposure. This corroborates the possibility of the influenza vaccine alone causing SJS. Despite the initial adverse reaction, the patient made a full recovery. Although the disease can be associated with vaccinations, the benefits of receiving the vaccinations outweigh the potential harms.

Human adenovirus Coinfection aggravates the severity of Mycoplasma pneumoniae pneumonia in children

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae) is an important pathogen of community-acquired pneumonia (CAP) in children. The coinfection rate of M. pneumoniae pneumonia (MPP) can reach 52% in some areas, but the effects of coinfection with different pathogens have not been clearly recognized.

METHODS

The cases of MPP hospitalized in Beijing Children's Hospital from 1/1/2014 to 12/31/2016 were screened. MPP patients coinfected with Human adenovirus (HAdV) were categorized into the research group. Patients with single M. pneumoniae infection were categorized into the control group, matching the research group by age and admission time with a ratio of 1:3. Clinical manifestations, laboratory examinations, and disease severity were compared between these two groups.

RESULTS

A total of 2540 hospitalized MPP cases were screened in Beijing Children's Hospital, among which thirty cases were enrolled in the research group and ninety cases were enrolled in the control group. The results indicated that patients in the research group had longer hospital stays, longer fever durations and a higher rate of dyspnea, as well as a larger proportion applications of oxygen therapy and noninvasive continuous positive airway pressure (NCPAP). No obvious differences were found in lab examinations within the two groups. Regarding disease severity, the proportions of extremely severe pneumonia and severe disease defined by the clinical score system were higher in the research group than in the control group.

CONCLUSION

Compared with single M. pneumoniae infection, MPP coinfected with HAdV in children was relatively more serious.

Clinical Role of Serum Interleukin-17A in the Prediction of Refractory Mycoplasma pneumoniae Pneumonia in Children

Background

Mycoplasma pneumoniae pneumonia (MPP) is a common community-acquired pneumonia (CAP) in children, which may become refractory MPP (RMPP) to treatment.

Objective

The purpose of this study was to evaluate the clinical utility of measuring serum interleukin (IL)-17A to predict RMPP.

Patients and Methods

A retrospective clinical study at a single pediatric center included a review of the medical records of all children hospitalized for CAP between November 2015 and October 2019. The diagnosis of MPP was based on clinical presentation, chest radiography, and measurement of serum anti-Mycoplasma immunoglobulin IgM antibody titer using the microparticle agglutination method or sputum samples for Mycoplasma pneumoniae by PCR. Serum levels of IL-18 and IL-17A were determined by ELISA.

Results

Of the 625 children diagnosed with CAP, there were 154 children with MPP and without underlying diseases who were divided into a non-refractory MPP (NRMPP) group (n = 109) and a RMPP group (n = 45). The RMPP group had a higher incidence of tachypnea, cyanosis, hypoxia, segmental or lobar pneumonia, pleural effusion, and a longer period of hospitalization compared with NRMPP group (all P-values < 0.05). A serum IL-17A level above 10.8 pg/mL was a predictor for RMPP: area under the curve (AUC) 0.822; standard error (SE) 0.039; 95% confidence interval (CI) 0.746–0.897; diagnostic sensitivity and specificity of 77.8% and 77.1%, respectively. An LDH level above 436.5 IU/L and an IL-18 level above 464.5 pg/mL were the second most useful markers for RMPP: AUC 0.775, 0.775; SE 0.038, 0.039; 95% CI 0.700–0.850, 0.698–0.852; sensitivity 77.8%, 82.2%; specificity 62.4%, 59.6%; respectively.

Conclusion

This preliminary study of MPP in a pediatric population has shown that measurement of serum IL-17A may be a useful marker for the predictor of RMPP.

Mechanisms of Severe Cutaneous Adverse Reactions: Recent Advances

Cutaneous adverse drug reactions are unpredictable and include various different skin conditions of varying degrees of severity. The most concerning are usually referred to as severe cutaneous adverse reactions (SCARs) and include acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug-induced hypersensitivity syndrome (DiHS) or hypersensitivity syndrome (HSS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). All are delayed type IV hypersensitivity reactions in which a T-cell-mediated drug-specific immune response is responsible for causing the disease. Nonetheless, specific T-cell subpopulations develop in response to certain environmental conditions and produce cytokines that orchestrate the various phenotypes. Cytotoxic T lymphocytes (CTLs), T-helper type 1 (Th1), Th2, Th17, and regulatory T cells (Treg), among other T-cell subpopulations, participate in the development of SCAR phenotypes. Cell subpopulations belonging to the innate immune system, comprising natural killer cells, innate lymphoid cells, monocytes, macrophages and dendritic cells, can also participate in shaping specific immune responses in various clinical conditions. Additionally, tissue-resident cells, including keratinocytes, can contribute to epidermal damage by secreting chemokines that attract pro-inflammatory immunocytes. The final phenotypes in each clinical entity result from the complex interactions between a variety of cell lineages, their products, soluble mediators and genetic and environmental factors. Although the pathophysiology of these reactions is not fully understood, intensive research in recent years has led to major progress in our understanding of the contribution of certain cell types and soluble mediators to the variability of SCAR phenotypes.

Exanthematous Eruptions in Children

Childhood exanthems are commonly encountered by pediatricians in the hospital and the office. In the last several decades, we have seen a shift in the epidemiology of many of these diseases. After being deemed eliminated at the turn of 21st century, measles has experienced a resurgence secondary to falling vaccination rates, raising public health concerns. A new variant of hand, foot, and mouth disease caused by coxsackievirus A6 has been associated with more widespread and atypical disease, which can present diagnostic challenges to clinicians. Parvovirus B19, which is traditionally associated with fifth disease, is also the leading cause of papular purpuric gloves and socks syndrome, a rare condition with which providers may be unfamiliar. Since the introduction of routine vaccination, there has been a shift in the epidemiology and clinical presentation of primary varicella and herpes zoster. Finally, the recently described phenomenon of Mycoplasma pneumoniae-induced rash and mucositis will be discussed. [Pediatr Ann. 2020;49(3):e116-e123.].

Erythema multiforme, Stevens Johnson syndrome, and toxic epidermal necrolysis reported after vaccination, 1999-2017

BACKGROUND

Since the last review of vaccine safety surveillance data for erythema multiforme (EM), Stevens Johnson syndrome (SJS), SJS/TEN, and toxic epidermal necrolysis (TEN) (EM/SJS/TEN), over 37 new vaccines have been introduced in the United States. We sought to describe reported EM/SJS/TEN after vaccines during 1999-2017.

METHODS

We identified U.S. reports of EM/SJS/TEN received by the Vaccine Adverse Event Reporting System (VAERS) during 1999-2017. We stratified analysis by condition (EM, SJS, or TEN), and analyzed reports by serious or non-serious status, sex, age group, time from vaccination to symptom onset, exposure to known causes of EM/SJS/TEN, and vaccines administered. We used Empirical Bayesian data mining to detect vaccine-AE pairs reported more frequently than expected.

RESULTS

Of 466,027 reports to VAERS during 1999-2017, we identified 984 reports of EM, 89 reports of SJS, 6 reports of SJS/TEN, and 7 reports of TEN. Few reports of EM (9%), and most reports of SJS (52%), SJS/TEN (100%), and TEN (100%) were serious. Overall, 55% of reports described males, 48% described children aged < 4 years; 58% of EM/SJS/TEN occurred ≤ 7 days after vaccination. Few reports (≤5%) described exposure to known causes of EM/SJS/TEN. Overall, childhood vaccines (e.g., combined measles, mumps, and rubella vaccine) were most commonly reported. We identified 6 deaths; 4 were exposed to medications associated with EM/SJS/TEN. EM after smallpox vaccine was reported disproportionately among people aged 19-49 years.

CONCLUSIONS

EM/SJS/TEN were rarely reported after vaccination; data mining identified a known association between EM and smallpox vaccine.

Mycoplasma pneumoniae Among Children Hospitalized With Community-acquired Pneumonia

Background

The epidemiology of Mycoplasma pneumoniae (Mp) among US children (<18 years) hospitalized with community-acquired pneumonia (CAP) is poorly understood.

Methods

In the Etiology of Pneumonia in the Community study, we prospectively enrolled 2254 children hospitalized with radiographically confirmed pneumonia from January 2010-June 2012 and tested nasopharyngeal/oropharyngeal swabs for Mp using real-time polymerase chain reaction (PCR). Clinical and epidemiological features of Mp PCR-positive and -negative children were compared using logistic regression. Macrolide susceptibility was assessed by genotyping isolates.

Results

One hundred and eighty two (8%) children were Mp PCR-positive (median age, 7 years); 12% required intensive care and 26% had pleural effusion. No in-hospital deaths occurred. Macrolide resistance was found in 4% (6/169) isolates. Of 178 (98%) Mp PCR-positive children tested for copathogens, 50 (28%) had ≥1 copathogen detected. Variables significantly associated with higher odds of Mp detection included age (10-17 years: adjusted odds ratio [aOR], 10.7 [95% confidence interval {CI}, 5.4-21.1] and 5-9 years: aOR, 6.4 [95% CI, 3.4-12.1] vs 2-4 years), outpatient antibiotics ≤5 days preadmission (aOR, 2.3 [95% CI, 1.5-3.5]), and copathogen detection (aOR, 2.1 [95% CI, 1.3-3.3]). Clinical characteristics were non-specific.

Conclusions

Usually considered as a mild respiratory infection, Mp was the most commonly detected bacteria among children aged ≥5 years hospitalized with CAP, one-quarter of whom had codetections. Although associated with clinically nonspecific symptoms, there was a need for intensive care in some cases. Mycoplasma pneumoniae should be included in the differential diagnosis for school-aged children hospitalized with CAP.

Case Report: Clinical and Immunological Features of a Chinese Cohort With Mycoplasma-Induced Rash and Mucositis

Dermatological disorders are the most common extrapulmonary complications of Mycoplasma pneumoniae, of which Mycoplasma-induced rash and mucositis (MIRM) has recently been proposed to be a separate diagnostic entity. MIRM could easily be misdiagnosed as atypical Stevens-Johnson syndrome by clinicians due to the unawareness of this rare disease. We retrospectively reviewed the inpatient database from Jan. 2016 to Dec. 2019 of the Children's Hospital of Fudan University. In total, five patients (mean age 5.5 years, three male) matched the diagnostic criteria of MIRM. All patients had scattered lesions and more than two sites of mucosal involvement. The serum IgA level of three patients was higher than normal. Two patients had a significant decrease in peripheral blood CD3+ T and CD4+ T cells that improved with recovery. The percentage of TCRαβ+ CD4-CD8-T cells of Patient five was higher than normal. All patients received treatments with antibiotics and corticosteroids, 3 patients received intravenous immunoglobulin. Among five patients, three patients complained of dyspigmentation, and two patients had an uneventful recovery. MIRM is a separate entity with predominant mucosal involvement and excellent prognosis that more often affects younger patients. Excessive inflammatory reactions may lead to immune disorders, including lymphopenia and a redistribution of CD4+ T cells. We recommend that pneumonia accompanied by mucocutaneous eruptions, especially in young patients, should raise clinical suspicion of MIRM.

Outbreak of macrolide-resistant mycoplasma pneumoniae in a primary school in Beijing, China in 2018

Background

On 7th June, 2018, a primary school in Beijing, China notified Shunyi CDC of an outbreak of acute respiratory disease characterized by fever and cough among students and resulting in nine hospitalization cases during the preceding 2 weeks. We started an investigation to identify the etiologic agent, find additional cases, develop and implement control measures.

Methods

We defined probable cases as students, teachers and other staffs in the school developed fever (T ≥ 37.5 °C) with cough or sore throat; or a diagnosis of pneumonia during May 1–June 31, 2018. Confirmed cases were probable cases with Mycoplasma pneumoniae detected in oropharyngeal (OP) swabs by quantitative real-time polymerase chain reaction (qPCR). We searched case by reviewing school absenteeism records and interviewing students, teachers and staff in this school. Oropharyngeal swabs were collected from symptomatic students. Two qPCR) assay, a duplex qPCR assay, and sequencing were performed to determine the pathogen, genotype and macrolide resistance at the gene level, respectively.

Results

From May 1st to June 31st, 2018, we identified 55 cases (36 probable and 19 confirmed), of whom 25 (45%) were hospitalized for complications. All cases were students, none of the teachers and other staffs in the school were with similar symptoms. The attack rate (AR) was 3.9% (55/1398) for all students. The cases were mainly male (58%), with an age range of 7–8 years (median: 7 years). 72% (18/25) of inpatients had radiograph findings consistent with pneumonia, and some cases were hospitalized for up to 4 weeks. Pathogen detection results indicated that Mycoplasma pneumonia (M. pneumoniae) P1 type 1 was the causative agent in this outbreak, and the strain harbored one point mutation of A to G at position 2063.

Conclusions

The infections by macrolide-resistant M. pneumoniae are not always mild and pneumonia was common and M. pneumoniae could causes serious complications which require long-term hospitalization. In the future infectious disease prevention and control practice, M. pneumoniae should be paid more attention. It is necessary to establish and improve the pathogen and drug resistance surveillance system in order to prevent and control such mutated strains of M. pneumoniae from causing future outbreaks or epidemics in China.

The role of mixed Mycoplasma and Herpesvirus infections in case of skin lesions in children

Numerous literature data show the role of mycoplasma infection in the development of non-respiratory lesions of various organs and systems, including the skin. Herpesvirus and mycoplasma infections can trigger the development of immune-mediated inflammatory reactions of the skin and mucous membranes — erythema multiforme exudative, Stevens-Johnson syndrome, vesicular pustular dermatosis — Sneddon-Wilkinson syndrome, etc.

In order to study the frequency and nature of skin lesions with mycoplasmosis combined with herpesvirus infection, 45 patients aged 3 to 15 years of life were observed. A comprehensive clinical and laboratory study revealed skin lesions in 27 patients associated with current mycoplasma and herpesvirus infections. Thus, multiforme exudative erythema in the small form variant was diagnosed in 13 patients, skin vasculitis in 4, hemorrhagic purpura in 3, urticaria rash in 3, erythema nodosum in 2, mucositis in 2 children. In 18 children, a combined mycoplasma and herpesvirus infection was established. In 9 children, a mono infection was detected (in 5 — herpes virus and in 4 — mycoplasma).

All observed patients showed antibodies to smooth muscle antigens in titers from 1:80 to 1:160 (normal 1:40) and in the vast majority (in 24 patients) — antibodies to vascular endothelial antigens in titers from 1:80 to 1:320 (with the norm of 1:40). Compaction of the intima-media complex was detected in 6 patients with monoinfection and in 16 patients with co-infection, according to ultrasound duplex scanning of the vessels of the brachiocephalic department.

Thus, for various immuno-inflammatory, allergic skin diseases, screening for infections, in particular, mycoplasma and herpesvirus, is necessary to optimize treatment.

Extra-pulmonary diseases related to Mycoplasma pneumoniae in children: recent insights into the pathogenesis

PURPOSE OF REVIEW

Providing an overview on Mycoplasma pneumoniae-related extra-pulmonary diseases (MpEPDs) in children, who represent the preferred target population by those complications, and discussing the main pathogenic mechanisms implicated or potentially involved.

RECENT FINDINGS

Recent evidences supported the fact that M. pneumoniae is more than an extra-cellular pathogen colonizing epithelial cells of the respiratory tract. It is able to penetrate the cell membrane of host cells and to invade the respiratory mucosa, leading to pronounced inflammatory responses and also spreading outside the respiratory system, to some extent. Thus, direct and indirect (immune-mediated) mechanisms have been described in M. pneumoniae infections, but the latter ones have been mainly implicated in MpEPDs, as reviewed here. Recently, interesting insights have been provided, especially as concern neurologic complications, and new potential mechanisms of disease have been emerging for autoimmunity.

SUMMARY

The awareness of the occurrence of MpEPDs, showing very variable clinical expressions, could promote a correct diagnosis and an appropriate treatment. The knowledge of disease mechanisms in MpEPDs is largely incomplete, but recent advances from clinical studies and murine models might promote and direct future research.

Clinical features of Stevens-Johnson syndrome and toxic epidermal necrolysis

BACKGROUND

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, but these conditions are associated with high mortality. There have been few reports of SJS and TEN in children. The aim of this study was to evaluate the clinical features and outcomes of SJS and TEN in a group of Japanese children.

METHODS

We retrospectively reviewed pediatric cases of SJS and TEN, from 2000 to 2015.

RESULTS

We identified 12 pediatric cases of SJS and three of TEN. Six (all SJS) were caused by infection, and eight of the cases (SJS, n = 5; TEN, n = 3) were drug induced. Respiratory complications were the most common in terms of organ involvement, followed by hepatitis and gastrointestinal symptoms. Thirteen patients were treated with systemic corticosteroids, and two patients were treated with supportive therapy only. Concomitant with corticosteroid, four patients were given i.v. immunoglobulin. One patient with severe TEN was treated with systemic corticosteroids combined with plasmapheresis and cyclosporine. None of the present patients died. One patient with TEN had severe sequelae, with bronchiolitis obliterans and ocular involvement.

CONCLUSIONS

SJS/TEN are rare, but are associated with severe complications. General pediatricians need to have up-to-date information regarding these conditions. The present study provides insights into the confirmation of the risk of SJS/TEN as well as the treatment of these diseases.

Mycoplasma-Induced Rash and Mucositis in a Father and Son: A Case Report

This case report describes a father and son with recurrent Mycoplasma-induced rash and mucositis (MIRM). A father with a remote history of a similar rash in childhood presented to the hospital with a severe rash with mucosal involvement, and elevated Mycoplasma pneumoniae immunoglobulin M titers, consistent with MIRM. Four years later, a similar rash developed in his son with a positive M. pneumoniae polymerase chain reaction assay, which was consistent with MIRM. His course was complicated by recurrence of disease shortly after discharge from the hospital. To our knowledge, this case report is the first to describe recurrent MIRM affecting individuals within the same family.

Mycoplasma pneumoniae: A Potentially Severe Infection

Mycoplasma pneumoniae infections remain one of the most common etiologies of community-acquired pneumonia (CAP). The clinical presentation and manifestations vary widely and can affect all organs of the body. Diagnosis is challenging because there are no constant findings in physical exams or laboratory or radiological assessments that indicate Mycoplasma pneumoniae pneumonia, and specific diagnostic tools are not readily available. Extrapulmonary manifestations and severe pulmonary manifestations can lead to long-term sequelae. The increasing emergence of Mycoplasma pneumoniae that is resistant to macrolides in some areas of the world and increased world travel could add to the difficulty of controlling and treating Mycoplasma pneumoniae infections. We present a concise and up-to-date review of the current knowledge of Mycoplasma pneumoniae pneumonia.

A Retrospective Cohort Study of the Management and Outcomes of Children Hospitalized with Stevens-Johnson Syndrome or Toxic Epidermal Necrolysis

BACKGROUND

Severe cutaneous adverse reactions are rare yet life-threatening conditions. The current management and outcomes of these conditions in US children are unclear.

OBJECTIVE

To characterize the current management and outcomes of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) across US children's hospitals.

METHODS

We performed a retrospective cohort study of children younger than 18 years hospitalized with a primary diagnosis of SJS or TEN at 47 US freestanding children's hospitals. We compared treatment (intravenous immunoglobulin [IVIG], steroids, antibiotics, and others) and outcomes (length of stay [LOS], hospital mortality, readmission, recurrence, related complications, and adjusted hospital costs) across hospitals and by SJS versus TEN diagnoses.

RESULTS

We identified 898 pediatric patients hospitalized with a primary diagnosis of SJS or TEN. Of these patients, 167 (18.6%) were prescribed steroids only, 229 (25.5%) IVIG only, and 153 (17.04%) both IVIG and steroids. Median LOS was 8 days (interquartile range, 5-13) with median hospital-adjusted costs of $16,265. Readmissions were common, with 88 (9.9%) patients readmitted within 30 days of discharge and a recurrence rate of 2.7%. Overall hospital mortality in children was low at 0.56%. TEN was associated with higher mortality (3.23%) compared with SJS (0.13%). There was no association between the use of IVIG, systemic steroids, or IVIG and steroids during the first 2 days of hospitalization and decreased LOS or mechanical ventilation. Complex chronic conditions and TEN diagnoses were associated with increased LOS and increased odds of mechanical ventilation.

CONCLUSION

Survival in children with SJS and TEN is significantly better than that observed in adults. However, there is variability in the management and outcomes in children diagnosed with these severe cutaneous reactions. Further studies are needed to determine the most effective treatment strategies given the extent of health care utilization and high rate of readmissions observed in this population.

Clinical manifestations in infants and children with Mycoplasma pneumoniae infection

BACKGROUND

Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in older children. Pulmonary and extra-pulmonary symptoms associated with M. pneumoniae infection are reported. M. pneumoniae is mainly epidemic in Denmark with the recurrence every 4-7th year.

AIMS

Retrospectively, to describe the epidemiology and clinical features, in infants and children, during the M. pneumoniae epidemic in 2010 and 2011.

METHODS

All children under the age of 16 that were tested for M. pneumoniae during the period 01.02.2010-31.01.2012 were included. Medical charts, as well as radiological findings, were reviewed for all children with M. pneumoniae. A post-hoc analysis of viral co-infections was done on part of the cohort.

RESULTS

134 of 746 children were tested positive for M. pneumoniae by PCR or serology. Positive tests were found in 65% of children seven years and older, in 30% of 2-6-year-olds and 4% of infants (less than two years of age). Viral co-infection was found in 27% of the tested samples. The clinical presentation was a cough, asthma-like symptoms and low-grade fever. Extra-pulmonary symptoms were common and presented as nausea/vomiting by 33% of the children and skin manifestations by 25%. 84% of the children had a chest x-ray taken, and there were positive radiological findings in 94% of these.

CONCLUSION

M. pneumoniae also affected infants and young children and symptoms were similar to infections with respiratory viruses, but severe LRTI were also seen. During an up-coming epidemic, assessment of extra-pulmonary manifestations can be helpful when diagnosing M. pneumoniae infections.

Clinical and histologic features of Mycoplasma pneumoniae-related erythema multiforme: A single-center series of 33 cases compared with 100 cases induced by other causes

BACKGROUND

Mycoplasma pneumoniae infection has been documented in erythema multiforme (EM) and Stevens-Johnson syndrome-toxic epidermal necrosis (SJS-TEN). Clinical aspects of M pneumoniae-related EM have been poorly described in the literature.

OBJECTIVE

To highlight differences between M pneumoniae EM and non-M pneumoniae EM.

METHODS

This single-center, retrospective cohort study included all patients admitted to our dermatology department for EM during 2000-2015. We compared epidemiologic, clinical, and histologic data and follow-up for M pneumoniae EM and non-M pneumoniae EM cases.

RESULTS

Thirty-three patients with M pneumoniae EM were compared with 100 patients with non-M pneumoniae EM. Disease onset in winter was more frequent with M pneumoniae EM (P = .003). Acrally distributed lesions (32% vs 88%, P < .0001) and typical targets (45% vs 74%, P = .01) were less common in M pneumoniae EM than non-M pneumoniae EM. Multiple (≥2) mucousal membrane involvement was more frequent in M pneumoniae EM than non-M pneumoniae EM (97% vs 60%; P < .0001), as were mucosal and respiratory tract sequelae (P < .05). The mean hospital stay was longer with M pneumoniae EM patients: 9.5 days versus 5.1 days (P = .0002). A TEN-like pattern was observed in all 14 (100%) M pneumoniae EM skin biopsies versus 10 of 27 (48%) non-M pneumoniae EM biopsies (P < .001).

LIMITATIONS

The retrospective design.

CONCLUSION

M pneumoniae EM has a distinctive presentation compared with non-M pneumoniae EM, with more diffuse and atypical targets, more mucositis and respiratory tract sequelae. Histologic data show a TEN-like pattern in all M pneumoniae EM skin samples.

An Updated Review of the Molecular Mechanisms in Drug Hypersensitivity

Drug hypersensitivity may manifest ranging from milder skin reactions (e.g., maculopapular exanthema and urticaria) to severe systemic reactions, such as anaphylaxis, drug reactions with eosinophilia and systemic symptoms (DRESS)/drug-induced hypersensitivity syndrome (DIHS), or Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). Current pharmacogenomic studies have made important strides in the prevention of some drug hypersensitivity through the identification of relevant genetic variants, particularly for genes encoding drug-metabolizing enzymes and human leukocyte antigens (HLAs). The associations identified by these studies are usually drug, phenotype, and ethnic specific. The drug presentation models that explain how small drug antigens might interact with HLA and T cell receptor (TCR) molecules in drug hypersensitivity include the hapten theory, the p-i concept, the altered peptide repertoire model, and the altered TCR repertoire model. The broad spectrum of clinical manifestations of drug hypersensitivity involving different drugs, as well as the various pathomechanisms involved, makes the diagnosis and management of it more challenging. This review highlights recent advances in our understanding of the predisposing factors, immune mechanisms, pathogenesis, diagnostic tools, and therapeutic approaches for drug hypersensitivity.

The Epidemiology of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in China

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are life-threatening disease. However, there are only few epidemiologic studies of SJS/TEN from China. To analyze the clinical characteristics, causality, and outcome of treatment for SJS/TEN in China, we reviewed case reports of patients with SJS/TEN from the China National Knowledge Infrastructure (CNKI) and Wanfang database from 2006 to 2016 and patients with SJS/TEN who were admitted to the First Affiliated Hospital of Fujian Medical University during the same period. There were 166 patients enrolled, including 70 SJS, 2 SJS/TEN overlap, and 94 TEN. The most common offending drugs were antibiotics (29.5%) and anticonvulsants (24.1%). Carbamazepine, allopurinol, and penicillins were the most common single offending drugs (17.5%, 9.6%, and 7.2%). Chinese patent medicines accounted for 5.4%. There were 76 (45.8%) patients receiving systemic steroid and intravenous immunoglobulin (IVIG) in combination therapy, especially for TEN (80.3%), and others were treated with systemic steroids alone. Mortality rate of combination treatment comparing with steroid alone in TEN patients had no statistical significance. In conclusion, carbamazepine and allopurinol were the leading causative drugs for SJS/TEN in China. Combination of IVIG and steroids is a common treatment for TEN, but its efficacy in improving mortality needs further investigation.

SJS/TEN 2017: Building Multidisciplinary Networks to Drive Science and Translation

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a life-threatening, immunologically mediated, and usually drug-induced disease with a high burden to individuals, their families, and society with an annual incidence of 1 to 5 per 1,000,000. To effect significant reduction in short- and long-term morbidity and mortality, and advance clinical care and research, coordination of multiple medical, surgical, behavioral, and basic scientific disciplines is required. On March 2, 2017, an investigator-driven meeting was held immediately before the American Academy of Dermatology Annual meeting for the central purpose of assembling, for the first time in the United States, clinicians and scientists from multiple disciplines involved in SJS/TEN clinical care and basic science research. As a product of this meeting, this article summarizes the current state of knowledge and expert opinion related to SJS/TEN covering a broad spectrum of topics including epidemiology and pharmacogenomic networks; clinical management and complications; special populations such as pediatrics, the elderly, and pregnant women; regulatory issues and the electronic health record; new agents that cause SJS/TEN; pharmacogenomics and immunopathogenesis; and the patient perspective. Goals include the maintenance of a durable and productive multidisciplinary network that will significantly further scientific progress and translation into prevention, early diagnosis, and management of SJS/TEN.

Severe Delayed Drug Reactions: Role of Genetics and Viral Infections

Adverse drug reactions (ADRs) are a significant source of patient morbidity and mortality and represent a major burden to health care systems and drug development. Up to 50% of such reactions are preventable. Although many ADRs can be predicted based on the on-target pharmacologic activity, ADRs arising from drug interactions with off-target receptors are recognized. Off-target ADRs include the immune-mediated ADRs (IM-ADRs) and pharmacologic drug effects. In this review, we discuss what is known about the immunogenetics and pathogenesis of IM-ADRs and the hypothesized role of heterologous immunity in the development of IM-ADRs.

Characterization of Children With Recurrent Episodes of Stevens Johnson Syndrome

We performed a retrospective chart review for all cases of recurrent Stevens Johnson Syndrome (SJS) from March 2013 to March 2016. Nine children had 29 episodes of SJS or incomplete SJS; all children were male and 8 (88%) were white. Episodes affected mucus membranes with minimal skin involvement. Mycoplasma infections and HLA-B27/-B51 were common.

Mycoplasma pneumoniae from the Respiratory Tract and Beyond

Mycoplasma pneumoniae is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several years there has been much new information published concerning infections caused by this organism. New molecular-based tests for M. pneumoniae detection are now commercially available in the United States, and advances in molecular typing systems have enhanced understanding of the epidemiology of infections. More strains have had their entire genome sequences published, providing additional insights into pathogenic mechanisms. Clinically significant acquired macrolide resistance has emerged worldwide and is now complicating treatment. In vitro susceptibility testing methods have been standardized, and several new drugs that may be effective against this organism are undergoing development. This review focuses on the many new developments that have occurred over the past several years that enhance our understanding of this microbe, which is among the smallest bacterial pathogens but one of great clinical importance.