P. Kazanjian et al., Pneumocystis carinii cytochrome b mutations are associated with atovaquoneexposure in patients with AIDS, J INFEC DIS, 183(5), 2001, pp. 819-822
This retrospective cohort study was conducted to determine whether Pneumocy
stis carinii cytochrome b gene mutations in patients with AIDS and P. carin
ii pneumonia (PCP) are associated with atovaquone exposure. Portions of the
P. carinii cytochrome b genes that were obtained from 60 patients with AID
S and PCP from 6 medical centers between 1995 and 1999 were amplified and s
equenced by using polymerase chain reaction. Fifteen patients with previous
atovaquone prophylaxis or treatment exposure were matched with 45 patients
with no atovaquone exposure. Cytochrome b coenzyme Q binding site mutation
s were observed in 33% of isolates from patients exposed to atovaquone, com
pared with 6% from those who were not (P = .018). There was no difference i
n survival 1 month after treatment between patients with or without cytochr
ome b mutations (P = .14). Thus, cytochrome b mutations are significantly m
ore common in patients with AIDS and PCP with atovaquone exposure, but the
clinical significance of these mutations remains unknown.