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Clinical, Cosmetic and Investigational Dermatology 2018:11 37–39 Clinical, Cosmetic and Investigational Dermatology Dovepress submit your manuscript | www.dovepress.com Dovepress 37 R e s e a R C h L e t t e R open access to scientific and medical research Open Access Full Text Article http://dx.doi.org/10.2147/CCID.S136730 the effect of oral clindamycin and rifampicin combination therapy in patients with hidradenitis suppurativa in singapore harumi Ochi Lixian Chris tan hazel h Oon Department of Dermatology, National skin Centre, singapore Abstract: Hidradenitis suppurativa (HS) is a chronic inflammatory disease of follicular occlu- sion characterized by abscesses, draining sinuses, and scarring. The efficacy and tolerability of combination treatment with oral clindamycin and rifampicin have previously been assessed in 4 studies including groups of Caucasian patients. Overall results are promising with reported improvement rates between 71.4% and 85.7%. In this study, we propose that combination therapy is safe and efficacious in the treatment of HS, not only among Caucasians, but also in a group of Asian patients in Singapore. Keywords: hidradenitis suppurativa, combination therapy, clindamycin, rifampicin Introduction Hidradenitis suppurativa (HS) is a chronic inflammatory disease of follicular occlu- sion. Although HS is not primarily an infectious disease, Staphylococcus aureus and Staphylococcus epidermidis are pathogens most frequently isolated as secondary colonizers.1 In this study, we propose that combination therapy with oral clindamycin and rifampicin is efficacious in the treatment of HS in a group of Asian patients in Singapore. Methodology This retrospective study assessed the efficacy of a 10-week course of oral clindamycin 300 mg twice daily and oral rifampicin 300 mg twice daily in the treatment of HS. Patients who received this combination therapy between 1 December 2012 and 31 July 2013 in a tertiary dermatological center in Singapore were included. This study was approved as an audit by the Head of Acne Clinic of National Skin Centre (NSC), Singapore. As this was performed retrospectively, permission to access the medical records of the patients was granted by the Director of NSC. Patient consent was waived by the Head of Acne Clinic as data were de-identified and retrospective. Results Eleven patients (9 males) had a mean age of 24.5±8.8 years. There were 6 Chinese (54.5%), 4 Malays (36.3%) and 1 Indian (9.1%). Five were smokers (45.5%), 6 were obese (54.5%) and 1 had a family history of HS (9.1%). The duration of HS prior to commencement of oral clindamycin and rifampicin ranged from 2 to 20 years. Eight patients (72.7%) had previous treatments, including retinoids and antibiotics, with limited effect and persistent disease. At the end of 10 weeks of treatment, 7 of the Correspondence: harumi Ochi Department of Dermatology, National skin Centre, 1 Mandalay Road, 308205, singapore tel +65 6253 4455 Fax +65 6253 3225 email ochi.harumi@mohh.com.sg Journal name: Clinical, Cosmetic and Investigational Dermatology Article Designation: Research Letter Year: 2018 Volume: 11 Running head verso: Ochi et al Running head recto: Effect of oral clindamycin and rifampicin in hidradenitis suppurativa DOI: http://dx.doi.org/10.2147/CCID.S136730 http://www.dovepress.com/permissions.php www.dovepress.com www.dovepress.com www.dovepress.com https://www.facebook.com/DoveMedicalPress/ https://www.linkedin.com/company/dove-medical-press https://twitter.com/dovepress https://www.youtube.com/user/dovepress Clinical, Cosmetic and Investigational Dermatology 2018:11submit your manuscript | www.dovepress.com Dovepress Dovepress 38 Ochi et al 11 patients (63.6%) reported clinical improvement. Four patients had digital photography documenting response before and after treatment, and 2 blinded assessors evaluated the improvement using the HS Physician Global Assessment (PGA) score. Three patients achieved clear, minimal or mild scoring from all sites after completion of therapy, and 2 patients reported a 2-grade improvement relative to baseline from at least 1 site. There was only 1 patient (9.1%) who reported side effects of nausea and vomiting and 1 patient (9.1%) who defaulted follow-up (Table 1). Discussion The efficacy and tolerability of this combination treatment had previously been assessed in 4 studies. Overall results are promising with reported improvement rates between 71.4% and 85.7%.1–4 Statistically significant improvements in all quality-of-life dimensions of the Skindex-France question- naire were also described in 1 study.2 It is hypothesized that both the antibacterial and anti- inflammatory properties of clindamycin and rifampicin are responsible for the beneficial effects in treating HS. Clindamycin is a lincosamide antibiotic that is active against Gram-positive cocci and anaerobic bacteria. It mediates inflammation by suppressing complement-derived che- motaxis of polymorphonuclear leukocytes. Rifampicin is a lipid-soluble, broad-spectrum antibiotic highly effective against S. aureus. Additionally, it modifies cell-mediated hypersensitivity by suppressing antigen-induced transforma- tion of sensitized lymphocytes. Rapid emergence of bacterial resistance may result with rifampicin monotherapy.5 Hence, combination therapy is synergistic with reduced resistance rates and increased anti-inflammatory properties. Although Table 1 Demographics of patients, previous treatments, response and side effects of combination therapy Case number Age (years) Gender Duration of disease (years) Affected area(s) Prior therapy Physician clinical assessment Pretreatment PGA score Posttreatment PGA score Reported side effects 1 18 Male 2 axilla, neck Doxycycline, topical clindamycin Improved Nil Nil Nil 2 18 Male 4 Perineal Doxycycline, erythromycin, isotretinoin, minocycline Improved Nil Nil Nil 3 19 Male 9 Perineal Bactrim, cephalexin, doxycycline, erythromycin, isotretinoin, minocycline Improved 2.75 1.50 Nil 4 20 Male 6 Perineal, axilla augmentin, topical clindamycin Nonresponder Nil Nil Nil 5 21 Male 13 Perineal, axilla Doxycycline, topical clindamycin Improved 2.67 1.00 Nil 6 21 Male 3 Perineal, axilla, neck Nil Improved 1.75 2.00 Nil 7 21 Male 3 Perineal, back Defaulted Defaulted Nil Nil Nil 8 22 Male 5 Perineal Isotretinoin, minocycline, topical clindamycin Improved Nil Nil Nil 9 48 Male 20 Perineal, axilla augmentin, acitretin. ciprofloxacin, clindamycin, ceftriaxone, isotretinoin, infliximab Nonresponder 3.13 3.00 Nil 10 27 Female 7 Perineal, axilla Doxycycline, isotretinoin Nonresponder Nil Nil Nausea, vomiting 11 35 Female 2 Perineal, axilla Nil Improved Nil Nil Nil Abbreviation: PGa, hidradenitis suppurativa Physician Global assessment. www.dovepress.com www.dovepress.com www.dovepress.com Clinical, Cosmetic and Investigational Dermatology 2018:11 submit your manuscript | www.dovepress.com Dovepress Dovepress Clinical, Cosmetic and Investigational Dermatology Publish your work in this journal Submit your manuscript here: https://www.dovepress.com/clinical-cosmetic-and-investigational-dermatology-journal Clinical, Cosmetic and Investigational Dermatology is an interna- tional, peer-reviewed, open access, online journal that focuses on the latest clinical and experimental research in all aspects of skin disease and cosmetic interventions. This journal is included on PubMed. The manuscript management system is completely online and includes a very quick and fair peer-review system, which is all easy to use. Visit http://www.dovepress.com/testimonials.php to read real quotes from published authors Dovepress 39 effect of oral clindamycin and rifampicin in hidradenitis suppurativa a longer duration of treatment appears warranted in chronic diseases like HS, no large differences in outcome between patients treated for 10 weeks or more and those treated for a shorter period have been reported.4 Other studies have similarly described good tolerability with low rates of side effects between 13.0% and 38.2% (Table 2). Gastrointestinal complaints were most commonly reported, but there were no cases of clindamycin-associated Clostridium difficile colitis.1–4 In a recent systematic review of HS treatment, only combination clindamycin–rifampicin regimen, infliximab, Nd:YAG laser and surgical excision were considered effective treatments. However, some of these modalities have limitations. Infliximab has resulted in adverse events including severe allergic reactions, multifocal motor neu- ropathy and drug-induced lupus reactions. Recurrence rates of up to 42.8% after surgical excision have also been described.6 Conclusion Oral clindamycin and oral rifampicin combination therapy is safe and efficacious in the treatment of HS in groups of Caucasian and Asian patients in Singapore. Table 2 summarized data of the available studies on rifampicin–clindamycin in hs Reference Number of patients Treatment modalities Assessment of the severity of HS Number of patients with improvement Number of patients with side effects Bettoli et al1 23 Rifampicin 600 mg and clindamycin 600 mg for 10 weeks sartorius 17/20 (85%) 3 (13%) Number of exacerbations Gener et al2 116 Rifampicin 600 mg and clindamycin 600 mg for 10 weeks sartorius 60/70 (86%) 10 (14%) hurley skindex-France questionnaire hs Patient Global assessment Mendonça and Griffiths3 14 Rifampicin 600 mg and clindamycin 600 mg for 10 weeks No specific score 10/14 (71%) 4 (29%) van der Zee et al4 34 Rifampicin and clindamycin different dosages and duration hurley 28/34 (82%) 13 (38%) Investigator total assessment Present study 11 Rifampicin 600 mg and clindamycin 600 mg 10 weeks hs Physician Global assessment 7/11 (63.6%) 1 (9.1%) Abbreviation: hs, hidradenitis suppurativa. Acknowledgment The authors thank Dr Heng Yee Kiat for assisting with the PGA scoring. Disclosure Dr Hazel H Oon has received research grants from Pfizer and Novartis and acted as a speaker for Novartis, Galderma, and AbbVie. The authors report no other conflicts of interest in this work. References 1. Bettoli V, Zauli S, Borghi A, et al. Oral clindamycin and rifampicin in the treatment of hidradenitis suppurativa-acne inversa: a prospective study on 23 patients. J Eur Acad Dermatol Venereol. 2014;28(1):125–126. 2. Gener G, Canoui-Poitrine F, Revuz JE, et al. Combination therapy with clindamycin and rifampicin for hidradenitis suppurativa: a series of 116 consecutive patients. Dermatology. 2009;219(2):148–154. 3. Mendonça CO, Griffiths CE. Clindamycin and rifampicin combina- tion therapy for hidradenitis suppurativa. Br J Dermatol. 2006;154(5): 977–978. 4. van der Zee HH, Boer J, Prens EP, Jemec GB. The effect of combined treatment with oral clindamycin and oral rifampicin in patients with hidradenitis suppurativa. Dermatology. 2009;219(2):143–147. 5. Van Vlem B, Vanholder R, De Paepe P, Vogelaers D, Ringoir S. Immuno- modulating effects of antibiotics: literature review. Infection. 1996;24(4): 275–291. 6. Rambhatla PV, Lim HW, Hamzavi I. A systematic review of treatments for hidradenitis suppurativa. Arch Dermatol. 2012;148(4):439–446. www.dovepress.com www.dovepress.com www.dovepress.com Publication Info 4: