Methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus produce antimicrobial substances against members of the skin microbiota in children with atopic dermatitis.

Coagulase-negative Staphylococcus (CoNS) species inhibiting Staphylococcus aureus has been described in the skin of atopic dermatitis (AD) patients. This study evaluated whether Staphylococcus spp. from the skin and nares of AD and non-AD children produced antimicrobial substances (AMS). AMS production was screened by an overlay method and tested against NaOH, proteases and 30 indicator strains. Clonality was assessed by pulsed-field gel electrophoresis. Proteinaceous AMS-producers were investigated for autoimmunity by the overlay method and presence of bacteriocin genes by polymerase chain reaction. Two AMS-producers had their genome screened for AMS genes. A methicillin-resistant S. aureus (MRSA) produced proteinaceous AMS that inhibited 51.7% of the staphylococcal indicator strains, and it was active against 60% of the colonies selected from the AD child where it was isolated. On the other hand, 57 (8.8%) CoNS from the nares and skin of AD and non-AD children, most of them S. epidermidis (45.6%), reduced the growth of S. aureus and other CoNS species. Bacteriocin-related genes were detected in the genomes of AMS-producers. AMS production by CoNS inhibited S. aureus and other skin microbiota species from children with AD. Furthermore, an MRSA colonizing a child with AD produced AMS, reinforcing its contribution to dysbiosis and disease severity.

Methicillin-resistant and methicillin-sensitive Staphylococcus aureus isolates from skin and nares of Brazilian children with atopic dermatitis demonstrate high level of clonal diversity.

BACKGROUND: Atopic dermatitis (AD) primarily affects the pediatric population, which is highly colonized by S. aureus. However, little is known about the genetic features of this microorganism and other staphylococcal species that colonize AD patients. OBJECTIVE: This study aimed to characterize Staphylococcus spp. isolated from the nares and skin (with and without lesion) of 30 AD and 12 non-AD Brazilian children. METHODS: Skin and nasal swabs were cultured onto mannitol salt agar, and bacterial colonies were counted and identified by matrix assisted laser desorption ionization time of flight mass spectrometry and polymerase chain reaction (PCR). Antimicrobial susceptibility was evaluated by phenotypic and genotypic tests. In S. aureus isolates, Panton-Valentine leukocidin genes were detected by PCR, and their clonality was assessed by pulsed-field gel electrophoresis and multilocus sequence typing. RESULTS: S. aureus was more prevalent in the nares (P = 0.005) and lesional skin (P = 0.0002) of children with AD, while S. hominis was more frequent in the skin of non-AD children (P < 0.0001). All children in the study, except one from each group, were colonized by methicillin-resistant coagulase-negative Staphylococcus and 24% by methicillin-resistant S. aureus. Despite the great clonal diversity of S. aureus (18 sequence types identified), most AD children (74.1%) were colonized by the same genotype in both niches. CONCLUSION: High colonization by polyclonal S. aureus isolates was found among children with AD, while S. hominis was more frequent among non-AD children. The high prevalence of methicillin-resistant staphylococcal isolates highlights the importance of continued surveillance, especially when considering empiric antibiotic therapy for the treatment of skin infections in these patients.

Clinical oral profile of pediatric patients with atopic dermatitis: A cross-sectional study.

OBJECTIVES: This work aims to describe oral health conditions, eating habits, and oral hygiene in pediatric and adolescent patients with atopic dermatitis and correlate them with the severity of the Scoring Atopic Dermatitis (SCORAD). Also, we aim to estimate the effect of several variables on the diagnosis of dental caries in these patients. MATERIAL AND METHODS: A total of 92 children and adolescents with atopic dermatitis had their oral cavities examined. The effect of independent variables on the diagnosis of dental caries (outcome) was assessed using multiple binary logistic regression model. RESULTS: Mild patients presented higher score of decayed, missing, and filled teeth in permanent dentition than moderate patients (p = 0.040). In the multivariable regression final model, the covariates using inhaled corticoid (OR = 6.4; p = 0.003), type of teething [deciduous dentition (OR = 7.9; p = 0.027) and mixed dentition (OR = 10.5; p = 0.007)], and brushing quality [poor mechanical control (OR = 10.6; p < 0.0001)] demonstrated significant direct effect on the diagnosis of dental caries. CONCLUSIONS: Our findings suggest that the presence of dental biofilm, use of inhaled corticoid, and type of teething are related to the presence of caries in atopic dermatitis patients.

Oral Aspects Identified in Atopic Dermatitis Patients: A Literature Review.

INTRODUCTION: Atopic dermatitis is a chronic inflammatory skin condition that is more prevalent in children (10-20% of the world's population) than in adults. As its etiology is multifactorial, it is important to know the most frequent oral manifestations in atopic dermatitis patients. METHODOLOGY: In the last decades, the correlation between atopic dermatitis and conditions and/or changes in the oral cavity has been demonstrated by several studies. The objective of this paper was to describe, through a review of the literature, the oral health conditions and/or oral aspects identified in patients with atopic dermatitis. SEARCH STRATEGY: A descriptive literature review was carried out through a bibliographical survey based on the last 10 years, in order to answer the study questions. RESULTS: As a result, we found six studies with different sample sizes, ranging from 43 to 468 patients, and the majority of them were of cross-sectional study design. DISCUSSION: Two studies performed their analysis through dental exams and reported that patients with atopic dermatitis tend to have a greater frequency of carious lesions, and two studies correlated Candida with atopic dermatitis through mycological analyzes. CONCLUSION: There are a few studies in the literature that identify the oral aspects of atopic dermatitis. More investigations are needed in order to contribute to the knowledge of such oral aspects and the approach to treat these patients regarding oral health.

Eritema nodoso na criança: relato de quatro casos / Erythema nodosum in children: report of four cases

Foram estudadas quatro crianças com diagnóstico clínico e histopatológico de eritema nodoso. Como fatores citológicos: tuberculose pulmonar (um caso), infecçåo estreptocócica (um caso), Dipirona (um caso); em um caso nåo se detectou a etiologia. Destacam-se a ausência de publicaçöes em nosso meioe o interesse do eritema nodoso no diagnóstico de doenças gerais associadas