What Do Physicians Know About Cryptosporidiosis?

Outbreaks of cryptosporidiosis, induced by the protozoan parasite Cryptosporidium parvum have been reported secondary to contaminated water, raw milk, unpasteurized apple cider, public drinking water, exposures at day care centers, and while swimming in contaminated water. Knowledge about C. parvum has been reduced because it is easily mistaken for yeast on standard ova and parasite examinations, and clinicians often are unaware that special testing may be required to identify C. parvum with certainty.

In an effort to further elucidate the level of clinician knowledge in Connecticut, 730 physicians (gastroenterologists, general or family physicians, infectious disease specialists, internists, and pediatricians, all approximately comparably represented) received self-administered questionnaires. Questions sought knowledge base about persons who were at risk for, symptoms of, and laboratory diagnosis of C. parvum.

Although most respondents recognized AIDS as an increased risk for C. parvum, children in day care, overseas travelers, and persons in contact with farm animals were much less frequently recognized. Both infectious disease specialists and others incorrectly believed that nursing home residents were at increased risk.

More than one-third of all physicians, regardless of specialty, thought that a standard stool specimen for O&P was sufficient for evaluation of C. parvum. Physicians whose practice included at least 1% HIV positive patients were most likely to know that special testing is required.

There is substantial room for improvement in physicians’ knowledge about C. parvum. Though cost may be a potential barrier for ordering special tests (approximately $29 in hospital laboratories, $59 in clinical labs), elimination of further unnecessary evaluation of C. parvum infected persons may outweigh this expense.

Morin C. Arch Intern Med 1997;157: 1017-1022.