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

Abstract

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%) andEscherichia 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.

Clindamycin alone may be enough. Is it time to abandon rifampicin for hidradenitis suppurativa?

“…Lesional samples were particularly enriched in anaerobic Gram‐negative bacteria . Other studies showed a polymicrobial microflora in HS lesions, dominated mainly by Gram‐positive cocci, while Enterobacteriaceae was the most frequent family isolated among Gram‐negative strains …”

“…In fact, anaerobes were recovered from 95% and 100% of Hurley stage II and III lesions, respectively, compared with 54% of Hurley stage I nodules and abscesses . Lesional samples were particularly enriched in anaerobic Gram‐negative bacteria . Other studies showed a polymicrobial microflora in HS lesions, dominated mainly by Gram‐positive cocci, while Enterobacteriaceae was the most frequent family isolated among Gram‐negative strains …”

“…We speculated that the lower clindamycin concentration due to the inhibitory effect of rifampicin could reduce the strength of the treatment itself in severe HS lesions such as the draining tunnels, which are often colonized by polymorph‐abundant anaerobic microflora . In fact, anaerobes were recovered from 95% and 100% of Hurley stage II and III lesions, respectively, compared with 54% of Hurley stage I nodules and abscesses . Lesional samples were particularly enriched in anaerobic Gram‐negative bacteria .…”

Surgical and postsurgical wound care in hidradenitis suppurativa

“…Multiple treatments have been described for the management of HS patients (Alikhan et al, ; ; Bettoli, Manfredini, Calamo, et al, ; Bettoli, Manfredini, Massoli, et al, ). Surgical approaches are a quite common therapeutic modality for severe HS, even though postsurgical management is usually more complex with respect to other because of the large areas involved and of the ongoing inflammatory process in the adjacent involved skin areas (Garbarino, Manfredini, Rossi, & Magnoni, ).…”

Clindamycin alone may be enough. Is it time to abandon rifampicin for hidradenitis suppurativa? Reply from the authors

“…The development of resistance in HS is a challenging subject, but it seems to be clear that the resistance to clindamycin in HS is high, and increasing in anaerobes, so we are sceptical that the antibiotic effect of clindamycin can explain the results observed by Caposiena Caro et al . We also disagree with the arguments about rifampicin and tuberculosis and have made the case previously in this journal .…”