Erythema Multiforme in Children and Mycoplasma pneumoniae Aetiology.

Erythema multiforme (EM) in children is understudied and confused with Stevens-Johnson syndrome (SJS) despite their being separate diseases with unique aetiologies and clinical presentations. The goal of this study was to determine the prevalence of Mycoplasma pneumoniae in paediatric patients with EM minor, EM major (EMM), and SJS. This retrospective cohort at The Hospital for Sick Children accrued all cases of EM minor, EMM, and SJS from 1999 to 2013. Sixty-five cases were identified: 20 of EM minor, 23 of EMM, and 22 of SJS. Aetiologies were attributed in 58% of cases: 79% infection and 21% drug aetiology. Sixty-one percent of patients with EMM were M pneumoniae positive, compared with 14% of those with SJS and 22% of those with EM minor (P < .01). M pneumoniae patients were older at presentation (P = .03) and more frequently had sore throat (P < .01) and atypical targets with central blistering (P < .01). These findings suggest that M pneumoniae should be suspected and treated until laboratory confirmation becomes available in patients presenting with atypical target lesions with central blistering.

Colonization with community-acquired methicillin-resistant Staphylococcus aureus in children with atopic dermatitis: a cross-sectional study.

BACKGROUND: Bacterial infection with Staphylococcus aureus is a common complication of atopic dermatitis (AD). The incidence of community-acquired methicillin-resistant S. aureus infection (MRSA) in the AD population is unknown. OBJECTIVES: This study aimed to assess the prevalence of S. aureus and MRSA in pediatric patients with AD, to compare disease severity, and to characterize the clonal diversity of the isolates. METHODS: We carried out a prospective, cross-sectional study of 200 patients with AD. The severity of AD was defined as mild, moderate, or severe depending on a composite AD severity score. A swab was taken from the nares of each patient and another from affected skin or folds. Genotyping of all S. aureus isolates was conducted by polymerase chain reaction (PCR) amplification of the S. aureus protein A (spa) gene. RESULTS: According to the severity score, 66.5% of subjects were ranked as having mild AD, 29.5% as having moderate and 4% as having severe AD. Staphylococcus aureus colonization was seen in 61.5% of all patients, represented by 43.7% of skin swabs and 48% of nares swabs. Only one of the isolations represented MRSA. Older age and higher AD severity scores were associated with S. aureus colonization (P = 0.03 and P < 0.001, respectively). No significant associations were noted for attendance at day care, family members with frequent skin infections, or family members working in healthcare. Isolates from spa CC015 were cultured in 19.2% of patient samples. The single MRSA culture showed a new spa type that belonged to CC127. CONCLUSIONS: The results of this study confirm a high rate of S. aureus colonization of pediatric patients with AD. The low rate of MRSA requires further proof from larger prospective studies.