INEFFICACY OF INTESTINAL SECRETORY IMMUNE-RESPONSE TO CRYPTOSPORIDIUMIN ACQUIRED-IMMUNODEFICIENCY-SYNDROME

Background/Aims: An alteration of the secretory immune response has be en forwarded to explain frequent and chronic mucosal infections in pat ients with acquired immunodeficiency syndrome (AIDS). The aim of this study was to explore the intestinal immunoglobulin (lg) secretions in patients with AIDS and their relationships to cryptosporidiosis. Metho ds: Patients with AIDS and enteric cryptosporidiosis (n = 12), other e nteric infections (n = 10), and no identifiable enteric pathogen (n = 10) and human immunodeficiency virus-seronegative controls (n = 18) we re studied. The number of intestinal IgA and IgM plasma cells of the d uodenal lamina propria mucosa and total and anti-Cryptosporidium IgA, IgM, and IgG were measured in serum and feces. Results: Although not s ignificantly increased, the number of lgA and IgM plasma cells was gre ater in patients with AIDS (n = 20) than in controls (n = 5). In feces , total IgA outputs and specific anti-Cryptosporidium lgA levels were significantly higher in patients with AIDS and cryptosporidiosis than in the two other groups of patients with AIDS (P < 0.05 and P < 0.01, respectively) and controls (P < 0.001 and P < 0.01, respectively). Tot al fecal IgM output and specific anti-Cryptosporidium IgM coproantibod ies were increased only in the Cryptosporidium-infected patients relat ive to the controls (P < 0.05). Conclusions: Despite the development o f pathogen-specific mucosal antibody responses, patients with AIDS and cryptosporidiosis fail to clear the parasite.