Molecular testing for cryptosporidium (Cryptosporidium parvum) is used for the diagnosis and laboratory documentation of intestinal cryptosporidiosis.
Cryptosporidium is a protozoon of the coccidia group which is a common parasite in farm animals and can infect and survives in surface water. Cryptosporidium has a worldwide distribution and can be found in surface water, swimming pools, daycare centers, and hospitals. Human infection occurs through the fecal-oral route or the consumption of contaminated water. The precise mechanism by which the microorganism causes gastroenteritis is unknown.
Cryptosporidiosis occurs as severe diarrhea in immunosuppressed AIDS patients and as self-limiting mild diarrhea in young children.
The parasite is protected by an outer shell, which allows it to survive outside the host for long periods of time and makes it highly resistant. Boiling is the most common method of eliminating the parasite from water. In contrast, hand antiseptic gels have no effect on these microorganisms.
Cryptosporidium parvum can be detected by fecal parasitological examination, but the specificity and sensitivity of the method are low and may require up to 3 or more samples to make a diagnosis. Instead, molecular testing of feces for the presence of Cryptosporidium DNA using the technique of real-time PCR (RT-PCR), is a faster, more sensitive, and more effective method for detecting the parasite.