A Single Center, Prospective Clinical Trial of Intravenous Ertapenem in the Treatment of Hurley Stage II or III Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic, socially and cosmetically debilitating disease characterized by recurrent abscesses, draining sinus tracts, and scarring with a predilection for intertriginous skin folds.1 The lesions are painful and can drain malodorous fluid, leaving patients uncomfortable and self-conscious.1 It is not surprising that HS has a high degree of morbidity or that these patients have among the lowest quality of life scores of all skin disease.2-5

The pathophysiology of HS is not fully understood. It is thought to be multifactorial.1 The primary insult is believed to be follicular occlusion with hyperkeratinization and rupture of the follicle followed by bacterial colonization and biofilm formation.1 Most cultures of HS lesions are polymicrobial and commonly grow gram positive bacteria and anaerobes.6,7 A recent study observed evidence of biofilms in chronic HS lesions.8 Lesions with bacterial biofilms respond to antibiotics initially then demonstrate resistance as the bacteria develop metabolic adaptations and produce a protective layer, the extracellular matrix.1,8 This results in persistent, recalcitrant lesions.6 Lesions are difficult to treat and present significant frustration to both the patient and the provider.

The efficacy of antibiotics in HS has been explored. Antibiotics are commonly first line therapy in HS.1,9 Rifampicin, clindamycin, and tetracycline have successfully treated HS lesions.10,11 Other effective antibiotics include: carbapenems, fluoroquinolones, and penicillins with β-lactamase inhibitors.9 Triple therapy with oral rifampin, moxifloxacin, and metronidazole has been proposed.12 Although frequently successful in early stage disease, this regimen is less effective in Hurley stage II and III HS.12 Patients with Hurley stage II and III HS rarely experience remission on antibiotics alone. In chronic, recalcitrant HS, wide surgical excision is considered the treatment of choice.13 The Hurley Staging system is commonly utilized to classify the severity of a patient's hidradenitis suppurativa. Stage 1 disease consists of one or more abscesses with no sinus tract formation or scarring. Stage 2 disease involves one or more widely separated recurrent abscesses, with formation of a sinus tract and/or scarring. Stage 3 involves multiple interconnected sinus tracts and/or abscesses throughout an anatomical area.

In 2016, Join-Lambert et al investigated the use of intravenous (IV) ertapenem in 30 patients with severe, refractory HS.14 One gram of ertapenem daily for 6 weeks followed by consolidation antibiotics for 6 months demonstrated promising results in severe, recalcitrant HS.14 These patients reported significant improvements in pain, purulent drainage, and a decrease in handicap score.14 In this study, we propose the use of ertapenem for management of Hurley stage 2 and 3 hidradenitis suppurativa as a less invasive means of treating HS. The primary endpoint will be to determine the role of ertapenem in achieving Hidradenitis Suppurativa clinical response (HiSCR) at 6 weeks. HiSCR is defined as HS Clinical Response with ≥ 50% reduction from baseline in AN (total abscess and inflammatory nodule) count with no increase in abscess or in draining fistula counts. Secondary endpoints include a change in DLQI score from baseline to the end of week, work productivity and activity impairment (WPAI) outcome from baseline to the end of week six, C- reactive protein and hemoglobin from baseline to the end of 6 weeks, the change in HS-LASI from baseline to the end of week 6, and ultrasound changes from baseline to the end of week 6.

Study Synopsis