Mycobacterium ulcerans infection: treatment with rifampin, hyperbaric oxygenation, and heat.

The effectiveness of hyperbaric oxygenation (HBO), heat, and rifampin for treating mice infected with Mycobacterium ulcerans was analyzed. Four hundred mice were innouclated in the hind footpads with 10(8) organisms. The seven treatment groups (50 mice each) were HBO (2.5 ATA for 1.5 h, twice a day), rifampin (RIF) (20 mg/kg body weight/d), heat (mice maintained at 37 degrees C), and all combinations of the three treatments. The severity of infection in the treated mice was compared weekly for 20 weeks with that of infected controls. The most effective treatments were RIF/HEAT and RIF/HBO/HEAT, RIF/HBO/HEAT treatment was further evaluated to determine the effectiveness of treating mice at various stages of infection. Three hundred mice were inoculated in the hind footpads, and, as the infection progressed, they were separated into groups (50 mice/group) according to the severity of infection. The treatment groups were compared to positive controls. The effectiveness of therapy was indirectly proportional to the severity of infection.