Intestinal and extraintestinal cryptosporidiosis in AIDS patients

Abstract

In a prospective study in AIDS patients with chronic diarrhea, the overall prevalence of intestinal cryptosporidiosis was 15.6% (43/275). The prevalence was higher in homosexual patients (33.3%) than in intravenous drug abusers (10.6%) (p < 0.001). Extraintestinal infection was present in 30% (13/43) of the patients with known intestinal cryptosporidiosis. Eight of the 13 (61.5%) patients with extraintestinal cryptosporidiosis had Cryptosporidium in the bile and 7 of 13 (16.28%) had it in the sputum. Of the seven patients with Cryptosporidium in the sputum, four had respiratory symptoms and an abnormal chest radiograph, although another pulmonary pathogen was isolated simultaneously. Two other patients from whom Cryptosporidium was the sole respiratory pathogen isolated had no respiratory symptoms and normal chest radiographs. The seventh patient had pulmonary symptoms, interstitial infiltrate on chest radiograph and excessive activity on a pulmonary Gallium scan; Cryptosporidium was the only organism detected in induced sputum and bronchoalveolar lavage specimens. The mean CD4+ lymphocyte count in patients with extraintestinal cryptosporidiosis was 55 cells/mm3.

Cryptosporidium parvum is cytopathic for cultured human biliary epithelia via an apoptotic mechanism

“…The immune response to C. parvum is not completely understood, although a low CD4 count in AIDS patients is associated with chronic severe infection. 4 Although the clinical consequences of cryptosporidial infection have been documented, the pathophysiology is not well understood. Histological changes associated with intestinal cryptosporidiosis are relatively nonspecific, with blunting of villi, hyperplasia of intestinal crypt cells, and infiltration of inflammatory cells into the lamina propria.…”

“…Histologically, there is a periductal inflammatory response with interstitial edema, mixed inflammatory cell infiltrates, and hyperplasia and dilatation of the periductal glands. 3,4 Study of this parasitic infection has been difficult, in part because of the lack of experimental models for the disease, including cell culture systems. Relatively few epithelial cell lines will support growth of the organism in culture, and, to date, attention has focused on intestinal cryptosporidiosis, employing the intestinal cell lines, T84, Caco-2, and HCT-8, for most studies.…”

“…[3][4][5] Although the intestinal disease is selflimited and biliary abnormalities are not seen in immunecompetent individuals, C. parvum infection in AIDS patients is a chronic, debilitating condition, and involvement of the biliary tract is associated with a much poorer prognosis than with intestinal infection alone. 4 Although the actual frequency of biliary cryptosporidiosis in patients with AIDS is unclear and is related not only to the clinical stage of the disease, but also to the occurrence of episodes of water contamination with C. parvum, 6 some series report clinically detectable biliary infection in up to 15% of patients with advanced AIDS. 7 To date, there is no effective medical treatment for either intestinal or biliary cryptosporidiosis, and in AIDS patients, the infection is rarely spontaneously cleared.…”

Criptosporidiose pulmonar em pacientes com AIDS, uma doença subdiagnosticada

“…(1,2) In the pre-antiretroviral therapy (ART) era, intestinal cryptosporidiosis was responsible for diarrheal symptoms in 10-30% of AIDS patients in developed countries and in 30-50% of those in developing countries. (3) Currently, in developed countries in which the rates of environmental contamination are low and in which potent ART is widely available, intestinal cryptosporidiosis occurs at an incidence rate of < 1 per 100 personyears among AIDS patients. (4) Pulmonary impairment is a rare complication of intestinal cryptosporidiosis, having been reported in immunocompromised patients, most of whom have AIDS and severe immunodeficiency.…”

“…oocysts. (3) The pathogenesis of pulmonary cryptosporidiosis has yet to be fully clarified. (2,6) The possibility that pulmonary involvement is due to inhalation of oocysts during an episode of vomiting or results from hematogenous dissemination has been a point of discussion.…”