A controlled trial of bovine dialyzable leukocyte extract for cryptosporidiosis in patients with AIDS.

Cryptosporidial infection causes severe diarrheal disease in patients with AIDS. Fourteen patients with AIDS and symptomatic cryptosporidiosis were treated with a specific bovine dialyzable leukocyte extract (immune DLE) prepared from lymph node lymphocytes of calves immunized with cryptosporidia or a nonspecific (nonimmune) DLE prepared from nonimmunized calves. Six of 7 patients given immune DLE gained weight and had a decrease in bowel movement frequency, with eradication of oocysts from stool in 5 patients. Six of 7 patients given nonimmune DLE showed no decrease in bowel movement and 4, no clearing of oocytes from stool; 5 continued to lose weight. Subsequently, 5 of these 7 were treated with immune DLE; 4 had a decrease in bowel movement frequency and significant weight gain, with eradication of oocytes from stool in 2 patients. Immune DLE produces sustained symptomatic improvement in patients with AIDS and active cryptosporidiosis, but lack of an appropriate cryptosporidial antigen allows only postulation that an augmentation of cellular immunity to Cryptosporidium parvum induced by immune DLE resulted in the microbiologic and clinical improvement observed.