Rates of antibiotic resistance/sensitivity in bacterial cultures of hidradenitis suppurativa patients.

BACKGROUND: Antibiotic (AB) treatment is one of the first steps in the management of hidradenitis suppurativa (HS). Bacteria, in HS patients, may play a double role, as triggering factors of inflammatory reactions and/or agents of infection. OBJECTIVES: The aims of this study are as follows: (i) to assess prevalence and AB resistance of bacterial growths in HS patients (ii) assessment of the clinical relevance of obtained data in guiding the selection of the most effective AB therapy. METHODS: Purulent material from 137 skin lesions of HS patients was collected with swabs. Bacterial flora and AB sensitivity were determined using microbiological cultures for aerobic and anaerobic bacteria. RESULTS: A total of 114 samples resulted positive for bacteria. Sample was collected from the axillae, groin and perianal areas. A total of 163 single bacterial growths were observed; 55% were Gram-positive and 44% were Gram-negative. Among them, 18.4% were anaerobic. The most frequent bacterial families included enterobacteriaceae (30.7%), Staphylococcus (25.2%) and Streptococcus (14.1%). The most frequent genus or species were proteus spp. (13.5%) and Escherichia coli (9.8%). The prevalence of AB resistance observed was clindamycin 65.7%, rifampicin 69.3%, penicillin 70.0%, ciprofloxacin 74%, tetracycline 84.7% and erythromycin 89.0%. A limitation of the study is represented the short culture period adopted which may have impaired the isolation of anaerobes. CONCLUSIONS: Bacterial growth in HS patients has shown a high level of resistance to ABs, including rifampicin, clindamycin and tetracyclines, cited as an empiric choice in HS therapeutic guidelines. A targeted and specific AB therapy, driven by microbiological evaluations with prolonged culture periods, seems more appropriate than empiric, generic, non-specific, therapeutic approaches. Current knowledge regarding HS bacterial AB resistance should be considered in the update of current therapeutic guidelines for HS.

Colonization by multidrug-resistant organisms in long-term care facilities in Italy: a point-prevalence study.

OBJECTIVES: To determine prevalence and risk factors for colonization by multidrug-resistant organisms (MDROs) in long-term care facility (LTCF) residents in Italy. Genotypes of MDRO isolates were investigated. METHODS: A point-prevalence study was conducted at 12 LTCFs located in four Italian cities (2 February to 14 March 2015). Rectal swabs, faeces and nasal/auxiliary swabs were cultured for extended-spectrum ß-lactamase (ESBL)- and/or carbapenemase-producing Enterobacteriaceae, Clostridium difficile and methicillin-resistant Staphylococcus aureus (MRSA) respectively. Antimicrobial susceptibility testing, detection of ESBL and/or carbapenemase genes and molecular typing of MDROs were performed. Risk factors for colonization were determined by univariate and multivariate analysis. RESULTS: A total of 489 LTCF residents aged ≥65 years were enrolled. The prevalence of colonization by ESBL-producing Enterobacteriaceae, MRSA and C. difficile was 57.3% (279/487), 17.2% (84/487) and 5.1% (21/409) respectively. Carriage rate of carbapenemase-producing Enterobacteriaceae was 1% (5/487). Being bedridden was a common independent risk factor for colonization by all MDROs, although risk factors specific for each MDRO were identified. ESBL-producing Escherichia coli carriage was associated with the sequence type (ST) 131-H30 subclone, but other minor STs predominated in individual LTCF or in LTCFs located in the same city, suggesting a role for intrafacility or local transmission. Similarly, MRSA from LTCF residents belonged to the same spa types/ST clones (t008/ST8 and t032/ST22) commonly found in Italian acute-care hospitals, but infrequent spa types were recovered in individual LTCFs. The prevalent C. difficile PCR ribotypes were 356/607 and 018, both common in Italian acute-care hospitals. CONCLUSIONS: MDRO colonization is common among residents in Italian LTCFs.

Active surveillance for asymptomatic carriers of carbapenemase-producing Klebsiella pneumoniae in a hospital setting.

The spread of carbapenemase-producing Klebsiella pneumoniae (CPKP) is a challenging public health threat. Early identification and isolation of infected patients and carriers are key measures of control. This study describes a CPKP screening strategy in a tertiary Italian hospital. During the five-month study period, 1687 patients were screened by rectal swabs. Of these, 65 (3.9%) tested positive for CPKP; 5.1% of case contacts tested positive. Screening case contacts appears to be the essential surveillance component for detecting asymptomatic carriers of CPKP. The added value of selective CPKP screening on hospital admission depends on the frequency of carriers among incoming patients.