[Paradoxical reactions and responses during antibiotic treatment for Mycobacterium ulcerans infection (Buruli ulcer). Four cases from French Guiana]. / Réponses et réactions paradoxales au cours du traitement médicamenteux de l'infection à Mycobacterium ulcerans (ulcère de Buruli). Quatre observations en Guyane française.

BACKGROUND: In recent years, first-line therapy for Mycobacterium ulcerans infection in French Guiana has consisted of antibiotics active against this organism. Two regimens are used comprising rifampicin associated with clarithromycin or amikacin. PATIENTS AND METHODS: We describe four patients presenting apparent worsening of their lesions during treatment: ulceration of a nodular lesion in a 32-year-old woman and worsening of an ulcerated lesion in three patients aged 16, 27 and 79 years. DISCUSSION: In these 4 patients, we concluded that the symptoms were caused by a paradoxical response or a reaction, a phenomenon already described in tuberculosis and leprosy. Such worsening is transient and must not be misinterpreted as failure to respond to treatment. The most plausible pathophysiological hypothesis involves the re-emergence of potentially necrotizing cellular immunity secondary to the loss of mycolactone, a necrotizing and immunosuppressive toxin produced by M. ulcerans, resulting from the action of the antibiotics.

[Dermatologic manifestations associated with immune reconstitution syndrome in HIV+ patients starting HAART: a retrospective study in French Guiana]. / Manifestations dermatologiques associées au syndrome de restauration immunitaire du patient VIH+ débutant un traitement antirétroviral: etude rétrospective en Guyane française.

Immune reconstitution syndrome (IRIS) is an unusual inflammatory reaction to an opportunistic infection in an HIV-positive patient. This syndrome occurs when immunity is restored in the first months of an effective highly active antiretroviral treatment (HAART). First, we described all patients with a cutaneous form of IRIS. Then, between 1992 and 2004 we conducted a retrospective cohort study comparing Herpes Zoster and Herpes Simplex infections among untreated patients, patients treated by HAART for < or = six months, and patients treated for > six months. We observed three cases of atypical leprosy and three original observations: two of these were fistulisation of lymph node histoplasmosis and tuberculosis, the third one reports the recurrence of a treated cutaneous leishmaniasis. Multivariate analysis showed that, after controlling for age, sex and CD4 counts, patients receiving HAART for < or = six months were more likely to develop Herpes Zoster or herpes simplex infections (p < 0.005). Herpes Simplex and Herpes Zoster infections are the two most frequent dermatological manifestations in our tropical setting. Although mycobacterial infections are more rarely observed than in visceral IRIS, the increased incidence of leprosy may be quite significant when the availability of HAART spreads to developing countries.