For patients with hidradenitis suppurativa a short course of intravenous antibiotics given prior to longer term oral combined antibiotic therapy can deliver a fast response in symptoms, according to a study by dermatologists in Germany.

The effect of  a five day loading  dose  of  IV clindamycin  (3×600  mg/d)  given prior  to  the European recommended therapy of  10  to  12  weeks  clindamycin/rifampicin  combination treatment was investigated by clinicians at Dessau Medical Centre and the European Hidradenitis Suppurativa Foundation in 61 treatment-naïve patients with hidradenitis suppurativa.

The study population had a mean age of 42.5 years, mean onset of HS at 28.9 years, and 44% had Hurley stage III disease.

Clinically significant improvements were seen in HS severity, as measured by the International Hidradenitis Suppurativa Severity Score System (IHS4) , and quality of life (Dermatology Life Quality Index, DLQI) at all time points in the study.

For HS severity, the IHS4 median value was reduced from 10 at baseline, to 7 after the five day loading dose of clindamycin (p<0.001), and 4 at completion of combination therapy (p=0.4 in comparison to T1) .

For quality of life, the DLQI median value decreased from 17  at baseline to 8 at five days (p=0.002), and remained at this level at 12 weeks

The minimal clinical important difference for quality of life (DLQI3) was achieved in 56% of patients after the loading dose and in 63% of the patients, at the end of treatment.

Writing in the British Journal of Dermatology, the study investigators said clindamycin was used in hidradenitis suppurativa for its effects on inflammatory lesions, but the exact mechanism of its action was not know. The benefits in hidradenitis suppurativa may be due to reduction of bacterial load, but the investigators noted that serum clindamycin levels were greatly reduced after two weeks of oral treatment, possibly through the detected rifampicin-induced P450 enzyme upregulation.

They said the study had confirmed a significant benefit for the European guideline recommended treatment of oral antibiotic combination, with an additional rapid benefit from a loading dose.

They acknowledged that the use of IV clindamycin had the potential to cause adverse effects such as C. difficile colitis, but said no adverse events were reported in the study participants during the five-day loading treatment. Five patients discontinued oral treatment due to clindamycin-associated abdominal pain and/or diarrhoea and exanthema.

The study investigators suggested the rapid response seen in the study with a loading dose and early improvement in quality of life would act as an incentive for patients to adhere to longer term oral therapy.

“Loading  therapy  prior  to  a  combined  oral  clindamycin/rifampicin treatment could provide significant benefits for therapy-naive patients,” they concluded.