Enteric pathogens associated with gastrointestinal dysfunction in children with HIV infection

Area of Science:

• Pediatric Infectious Diseases
• Gastroenterology
• Immunology

Background:

• Gastrointestinal (GI) manifestations are frequent in children with human immunodeficiency virus (HIV) infection, leading to diarrhea, malabsorption, and growth failure.
• The exact causes and mechanisms of GI dysfunction in pediatric HIV are not fully understood.
• Standard microbiological tests often fail to identify pathogens in these cases.

Purpose of the Study:

• To investigate the presence of opportunistic pathogens in the intestinal tissue of HIV-infected children experiencing GI dysfunction or growth failure.
• To compare findings in HIV-infected children with those in HIV-uninfected children.

Main Methods:

• Immunocytochemical analysis of intestinal biopsy samples from 19 HIV-infected children with GI symptoms.
• Testing for antigens of Pneumocystis carinii, cytomegalovirus (CMV), and herpes simplex virus (HSV) using immunohistochemistry.
• Comparison with intestinal tissue samples from 10 HIV-uninfected children with non-infectious GI conditions.

Main Results:

• Opportunistic pathogens were detected in intestinal tissues of 8 (42%) of 19 HIV-infected children.
• Pneumocystis carinii was the most common pathogen (5/8), even in children on prophylaxis and without active pulmonary infection.
• CMV antigens were found in 4 children, and HSV in 1 child. Two children had multiple infections.
• No targeted pathogens were found in HIV-uninfected control patients (P < 0.01).

Conclusions:

• Opportunistic pathogens, including P. carinii, CMV, and HSV, can cause GI dysfunction in HIV-infected children, often missed by standard stool analysis.
• Intestinal P. carinii infection can occur despite standard prophylaxis for pulmonary disease.
• These findings highlight the importance of investigating opportunistic infections in the GI tract of pediatric HIV patients.