Bartonella Infections clinical trials

The Efficacy of Prednisone and Azithromycin in the Treatment of Patients With Cat Scratch Disease

Bartonella henselae is the etiologic agent of cat scratch disease (CSD). 90% of patients present with regional lymphadenitis (typical CSD) while 10% will have disease involving other organs, such as neuroretinitis, arthropathy, erythema nodosum, and encephalitis (atypical CSD). In most CSD cases resolution occurs in 2 to 3 months although a prolonged course often occurs. Data on the efficacy of antibiotic therapy in CSD is limited. Azithromycin has been shown to have a small favorable effect in a small comparative study and is commonly prescribed for CSD, however its overall effect is not satisfactory. Corticosteroids may be effective in the treatment of CSD for the following reasons: - Many experts believe that host response is involved in the pathogenesis of CSD and is responsible for the clinical manifestations rather than the direct effect of B. henselae. The absence of viable organisms in affected lymph nodes (in the presence of positive PCR for B. henselae DNA), and the fact that arthritis, arthralgia and erythema nodosum (that are often associated with autoimmune diseases) have been described in CSD, support this concept. - Corticosteroids have been anecdotally reported to have been administered to patients with CSD, apparently with some success. The purpose of this study is to evaluate the efficacy of corticosteroids in addition to azithromycin in CSD. The study hypothesis is that corticosteroids will improve out come. Ten patients with typical CSD will be treated with a 5-day oral course of prednisone (1 mg/kg up to 60 mg/day) and azithromycin (500 mg on day 1 and 250 mg on days 2-5). Patients will be under followed up for 3 months. Major outcome measures will include duration of symptoms and signs, with particular emphasis on affected lymph node size and duration using a specific scoring system (lymphadenitis score, LS). LS will be used to evaluate lymphadenitis at each follow-up visit. The time period from baseline LS until 75% and 90% reduction in LS in the treatment group will be compared with historical controls. The historical control group will be consisted of age, sex, and clinical manifestations-matched CSD patients who were treated with azithromycin without corticosteroids.