Illness linked to microbe in group that makes vinegar.

Researchers have identified a new bacterium in a severely ill patient. Other members of this microbial family, Acetobacteraceae, are used in the vinegar-making industry and aren't known to cause disease, says study coauthor David E. Greenberg, a physician at the National Institute of Allergy and Infectious Diseases in Bethesda, Md.

The patient, a 39-year-old man, had chronic granulomatous disease (CGD), a rare, inherited immune disorder that permits opportunistic pathogens to cause infections. This patient, who had a fever and infected lymph nodes in his lungs, had failed to respond to 3 months of antibiotic and other treatments. Analysis of lymph tissue removed from the patient revealed an Acetobacteraceae bacterium that differed from known microbes.

Experiments showed that this bacterium could multiply and cause illness in mice that were immune compromised, but Greenberg notes that it's not yet known whether it caused his patient's symptoms.

Examination of blood samples from 80 other CGD patients revealed that 10 percent carry the newly identified microbe. Among blood samples from healthy blood donors, about 5 percent harbored it.

After lymph surgery, Greenberg's patient has recovered.--N.S.