Cryptosporidiosis A07.2

Cryptosporidiosis is a parasitic, fecal-orally transmitted intestinal disease. It is caused by an infection with a coccidian parasite of the genus Cryptosporidium. Cryptosporidiosis in humans was originally believed to be caused by only one species, but since the advent of molecular studies, 15 other species have been discovered to cause this infection. Among them, Cryptosporidium hominis and Cryptosporidium parvum are the most common species (Sharma K et al. 2023).

Protozoan (genotypes: C. parvum and C. hominis). To date, 15 species are known that can infect humans, mammals, reptiles and fish. C. parvum infects humans and animals, C. hominis only infects humans. Fecal-oral transmission.

Alongside giardiasis, one of the most common intestinal parasitic diseases in humans.

Since the 1980s, there has initially been a significant increase in cases of the disease, particularly among HIV-infected people, but the numbers are currently declining due to HAART.

Mainly occurring in countries with poor hygienic conditions and among farmers who keep animals. 1-3% in immunocompetent people in industrialized countries, 7-10% in developing countries; the seroprevalence rates appear to be significantly higher: in the USA: 25-60%, in developing countries: 65-95%.

Incubation period: approx. 10 days.

Asymptomatic infection, mild diarrhea and severe enteritis are possible, as are acute and chronic courses.

In immunocompetent patients, self-limiting gastroenteritis with diarrhea (3-10 days) is usually observed.

Accompanying symptoms: weight loss, inappetence, nausea and vomiting as well as abdominal cramp-like pain (tenesmus).

Extraintestinal symptoms: arthralgia, eye pain, headache, fatigue.

The bile duct system may be affected. Then cholecystitis, sclerosing cholangitis, strictures, jaundice are seen.

Pulmonary involvement: non-specific respiratory symptoms such as cough.

Microscopy (detection of oocysts in stool, tissue, duodenal, bronchial and biliary fluid): fresh stool sample or formalin-fixed; stool concentration by flotation; light or phase contrast microscopy. Staining: Kinyoun (acid-fast staining), HE, Giemsa, Auramine, malachite green.

Antigen and antibody tests (ELISA)

PCR.

Spontaneous recovery possible after 10-14 days in immunocompetent patients.

Long and severe courses are more frequent in children and immunocompromised patients.

Immunocompetent patients (including children): Nitazoxanide (Alinia or Cryptaz): 2 times/day 500 mg p.o. for 3 days. Both preparations are not listed in Germany and are available from international pharmacies.

Immunosuppressed patients: Nitazoxanide 2 times/day 500 mg p.o. for 3 days. Alternatively: Paromomycin (Humatin) 25-35 mg/kg bw/day p.o. for 2-8 weeks, possibly in combination with azithromycin (Zithromax) 1 time/day 500 mg/day p.o. for 3 days.

According to studies, Rifaximin (Xifaxan) is very effective: 2 times/day 200 mg p.o. The preparation is not listed in Germany and is available from international pharmacies.

Volume and electrolyte substitution.

In HIV-infected persons: initiate, continue or optimize HAART if necessary.

Severe and prolonged courses in patients with disorders of the cellular and humoral immune response.

In immunocompetent patients, more than half develop a chronic disease. Approximately 10% of cases take a fulminant course.

Food and drinking water hygiene.

Toilet hygiene.

Spores can be eliminated by freezing, heating, ammonia and formalin.

Questionable prophylaxis with clarithromycin and rifabutin.

Remember! When sending stool samples, explicitly point out the suspicion of cryptosporidiosis. Otherwise cryptosporidia are often overlooked.

Remember! In accordance with § 7 Para. 1 No. 10 IfSG, direct or indirect detection of Cryptosporidium parvum, if it indicates an acute infection, must be reported to the public health department by name.

1. Caccio SM (2005) Molecular epidemiology of human cryptosporidiosis. Parassitologia 47: 185
2. Fox LM, Saravolatz LD (2005) Nitazoxanide: a new thiazolide antiparasitic agent. Clin Infect Dis 40: 1173
3. Sharma K et al. (2023) Cryptosporidiosis in India and the World: A Review. Infect Disord Drug Targets. 23:e030423215404.
4. Smith HV, Corcoran GD (2004) New drugs and treatment for cryptosporidiosis. Curr Opin Infect Dis 17: 557
5. Blanshard C, Shanson DC, Gazzard BG (1997) Pilot studies of azithromycin, letrazuril and paromomycin in the treatment of cryptosporidiosis. Int J STD AIDS 8: 124