Cryptosporidium enteritis is an infection of the small intestine that is caused by the parasite cryptosporidium. The main symptom is diarrhea.

Cryptosporidium has recently been recognized as a worldwide cause of diarrhea in all age groups -- yet its major impact has been among individuals with weakened immune systems (including people with HIV or AIDS) and transplant recipients. In these groups, this diarrheal infection is not just bothersome but can lead to severe, and potentially life-threatening, wasting and malnutrition.

The major risk factor is swallowing water contaminated by fecal matter. Young children, animal handlers, people with close contacts of infected individuals, and men who have sex with men are at higher risk.

Outbreaks have been linked to drinking from contaminated public water supplies, drinking unpasteurized cider, and swimming in contaminated pools and lakes.

• Watery diarrhea, usually large-volume and multiple times a day
• Abdominal cramping
• Nausea
• Malaise
• Malnutrition and weight loss (in severe cases)

• Stool ova and parasites exam
• Special staining of the stool (called AFB staining), since cryptosporidium stains positive with AFB
• Intestinal biopsy (rare)