Staphylococcus lugdunensis: case report and discussion

Clinical and microbiological properties of Staphylococcus lugdunensis skin infections

Staphylococcus lugdunensis is an emerging pathogen in skin and soft tissue infections that was previously considered a commensal. The aim of this study was to elucidate the characteristics of skin infections by S. lugdunensis and its appropriate management, in a tertiary referral medical center. The clinical files, bacterial cultures and histopathology reports of all S. lugdunensis isolates from skin infections over a period of 8 years (September 2009-September 2017) were reviewed. S. lugdunensis was isolated from 29 patients with skin infections, aged 7-89 years (mean 33.3 years). A state of immune suppression (drug-induced, malignancy or diabetes) was present in five patients (17%). Folliculitis and cutaneous pustulosis were the most common presentations (16 cases, 55%), followed by secondary infection of hidradenitis suppurativa (five cases, 17%). Other sources of isolation were infected molluscum contagiosum (two cases), folliculitis decalvans (one case), dissecting cellulitis (one case), abscess (one case), cyst (one case), impetigo (one case) and granuloma after trauma (one case). The in vitro antibiotic sensitivity tests showed susceptibility to most tested antibiotics, although a few isolates were resistant to gentamycin, penicillin and oxacillin. In 19 of 20 patients for whom follow ups were available, cutaneous manifestations improved or resolved with proper local and/or oral antibiotic therapy. S. lugdunensis may play a role as a primary or secondary pathogen in various skin infections, most commonly folliculitis and pustulosis. Proper antibiotic therapy may lead to improvement or resolution.

Hidradenitis suppurativa, a review of pathogenesis, associations and management. Part 1

Hidradenitis suppurativa is a chronic, painful, autoinflammatory condition resulting in nodules, abscesses and sinus tracts. We present an evidence-based review providing new understanding of the pathogenesis of hidradenitis suppurativa and associated comorbidities. By the nature of their speciality, dermatologists are uniquely positioned to investigate and treat patients with this condition. Data collected from a subspecialty hidradenitis suppurativa clinic (N = 106) and experiences thereof are discussed in this review.

Prevalence of methicillin resistance and macrolide-lincosamide-streptogramin B resistance in Staphylococcus haemolyticus among clinical strains at a tertiary-care hospital in Thailand

Staphylococcus spp. is a major cause of nosocomial infection and sepsis. However, increasing drug resistance is becoming a challenge to microbiologists. The purpose of this study was to identify and determine antimicrobial resistance phenotypes and drug resistance genes of clinical coagulase-negative staphylococci (CoNS) isolates at Mae Sot Hospital in Tak province, Thailand. A total of 229 CoNS isolates were collected from clinical specimens during two periods in 2014 and in 2015. Staphylococcus haemolyticus was the most prevalent species (37.55%), followed by S. epidermidis (21.83%), S. saprophyticus (11.79%) and S. hominis (11.35%) respectively. The remaining 17.48% of the organisms comprised S. capitis, S. arlettae, S. cohnii, S. equorum, S. xylosus, S. warneri, S. sciuri, S. pettenkoferi, S. kloosii and S. lugdunensis. Methicillin-resistant CoNS (MRCoNS), containing the mecA gene, were detected in 145 of 229 isolates, mostly found in S. haemolyticus and S. epidermidis. In addition, the differentiation of their macrolide–lincosamide–streptogramin B (MLS_B) resistance phenotypes was determined by the D-test and corresponding resistance genes. Among 125 erythromycin-resistant CoNS, the prevalence of constitutive type of MLS_B, inducible clindamycin resistance and macrolide–streptogramin B resistance phenotypes were 72, 13.60 and 14.40% respectively. These phenotypes were expressed in 80% of MRCoNS strains. In addition, the ermC gene (79.20%) was found to be more prevalent than the ermA gene (22.40%), especially among MRCoNS. These results indicate that CoNS may play an important role in spreading of drug resistance genes. More attention to these organisms in surveillance and monitoring programs is needed.