### Diagnosis Red bumps in [[HIV]] patients and other immunosuppressed patients, like transplants. When found in the liver, it is called bacillary peliosis and any organ can be involved. Serology, PCR, and biopsy make the diagnosis. ### Epidemiologic Risks [[HIV]] and cats. Bad combination. Actually, anything and cats is a bad combination. Except, perhaps, a speeding auto. ### Microbiology Due to *[[Bartonella]]* *henselae* (cats) or *B*. *quintana* ([[Lice]]) and they like growing in blood vessels. Other things that cause red bumps in [[HIV]] include [[Kaposi's Sarcoma]], *[[Mycobacterium]]* *avium*, and *[[Cryptococcus]]*. ### Empiric Therapy Empiric therapy is, one must admit, moronic. Given the differential mentioned above, it makes more sense to, oh, I don't know, MAKE A DIAGNOSIS. Then treat with [[Azithromycin]] OR [[erythromycin]] OR [[doxycycline]] (perhaps the drug of choice) OR a quinolone.