Cryptosporidiosis

Cryptosporidiosis is an infection with Cryptosporidium. Symptom is, along with other symptoms of a gastrointestinal disorder, a watery diarrhea. The disease in immunocompetent patients characteristically self-limiting, but can also run persistent and difficult in patients with AIDS. Diagnosis is made by the identification of the pathogen or antigen in the stool. The treatment of immunocompetent persons is done as needed with nitazoxanide (Note for the German reader. In Germany, the therapeutic trial for symptom reduction paromomycin, spiramycin, azithromycin and octreotide and possibly a therapeutic trial with Kälberkolostrum recommended). In patients with AIDS a highly active antiretroviral therapy and supportive care are applied.

Cryptosporidiosis is an infection with Cryptosporidium. Symptom is, along with other symptoms of a gastrointestinal disorder, a watery diarrhea. The disease in immunocompetent patients characteristically self-limiting, but can also run persistent and difficult in patients with AIDS. Diagnosis is made by the identification of the pathogen or antigen in the stool. The treatment of immunocompetent persons is done as needed with nitazoxanide (Note for the German reader. In Germany, the therapeutic trial for symptom reduction paromomycin, spiramycin, azithromycin and octreotide and possibly a therapeutic trial with Kälberkolostrum recommended). In patients with AIDS a highly active antiretroviral therapy and supportive care are applied. Pathophysiology Cryptosporidium are among the coccidia that proliferate in small intestinal epithelial cells of vertebrate hosts. Infective oocysts are released into the lumen and excreted in the stool. Very few oocytes (z. B., <100) are required to cause disease, increasing the risk grows of a human-to-human transmission. After ingestion by another vertebrate the oocyst releases sporozoites which are converted in intestinal epithelial cells in trophozoites multiply and produce oocysts which are released into the intestinal lumen and complete the cycle. Thin-walled oocysts are involved in a car infection. Oocysts are resistant to harsh conditions, including chlorine in quantities that are typically used in public water treatment plants and swimming pools despite the observance of recommended residual chlorine levels. Epidemiology Cryptosporidium parvum (cattle genotype) and C. hominis (human genotype) are responsible for most infections in humans. An infection may result from ingestion of contaminated food or fecal contaminated water (often water in public or private pools, hot tubs, water parks or streams), direct contact from person to person or zoonotic spread. The disease occurs worldwide. Cryptosporidiosis up to 7.3% of diarrheal diseases in the developed world is responsible for 0.6, in areas with poor sanitation conditions even more common. In Milwaukee, Wisconsin, 1993> 400,000 people were affected by a mass outbreak by drinking water, as the water supply of the city was polluted by waste water during the spring rain and the filter system was not working properly. in particular an increased risk have children and cared for travelers in foreign countries with a reduced standard of hygiene, immunocompromised patients and medical staff, patients with cryptosporidiosis. In daycare there were outbreaks. The low number of oocysts required to cause an infection, prolonged excretion of oocysts, the resistance of oocysts to chlorination and their small size increases the risk of swimming pools that are used by children in diapers. Severe chronic diarrhea kryptosporidienbedingte is particularly a problem in AIDS patients. Symptoms and signs The incubation period is about 1 week, and it comes at> 80% of infected people to clinically manifest disease. The onset is abrupt with severe aqueous diarrhea, abdominal cramps, less often with nausea, anorexia, fever and malaise. The symptoms persist usually about 1-2 weeks, rarely ? 1 month and then disappear. Even after the disappearance of symptoms oocysts can be excreted for several weeks in the stool. Asymptomatic shedding occurs frequently in older children in developing countries. When immunocompromised host the onset may insidiously, the diarrhea but be pronounced. As long as the immunodeficiency underlying is not corrected, the infection can persist and cause a life-long, non-treatable diarrhea. Some AIDS patients have been reported fluid losses of> 5 to 10 l / day. The most common site of infection in immunocompromised hosts is the intestine; However, other organs (eg. as bile ducts, pancreas, respiratory tract) can also be affected. Diagnostic enzyme immunoassay for fecal antigens Microscopic examination of the chair (special techniques required) The detection of acid fast oocysts in stool confirmed the clinical diagnosis, however, conventional methods of stool examination (i. E. A routine testing of the chair on eggs and parasites) are not reliable. The oocysts are excreted intermittently, so multiple stool samples may be required. Through various enrichment process, the yield can be increased. Cryptosporidium oocysts can be identified by phase contrast microscopy or by staining by the modified Ziehl-Neelsen or Kinjoun staining. Immunofluorescence microscopy with fluorescein-labeled monoclonal antibodies is more sensitive and specific. The enzyme immunoassay for the detection of fecal Cryptosporidium antigen is more sensitive than the microscopic examination on oocysts. There have been developed DNA-based assays for the detection and speciation of C. parvum and C. hominis. The DNA tests are available from the Centers for Disease Control and Prevention (CDC) and are likely to be more readily available in the future in reference laboratories. By an intestinal biopsy Cryptosporidium can be detected within epithelial cells. Therapy nitazoxanide in patients without AIDS Antiretroviral therapy (ART) in patients with AIDS plus high-dose nitazoxanide in immunocompetent people a cryptosporidiosis runs self-limiting. In persistent infections nitazoxanide can be used; the recommended doses to be given in 3 days of age 1-3 years: 100 mg 2 times a day age 4-11 years: 200 mg 2 times a day Age ? 12 years: 500 mg 2 times a day in patients with AIDS is an immune reconstitution with ART crucial. High-dose nitazoxanide (500 to 1000 mg two times daily) for 14 days has been ul successfully in adults with a CD count> 50 /. Symptoms have subsided after effective ART in some patients. supportive measures, oral and parenteral rehydration and hyperalimentation are indicated for immunocompromised patients. Prevention stools of patients with Cryptosporidiosis is highly infectious, so the hygiene measures for the handling of chair should be strictly followed. For handling clinical samples special biosecurity measures have been developed. The most reliable measure decontamination consists of boiling water; Only filters with pore sizes ? 1 micron remove (called “absolute 1 micron” or tested by the NSF standard no. 53) Cryptosporidium cysts. Important points Cryptosporidiosis spreads easily, since the fecal excretion of oocysts continued for weeks after the symptoms have subsided, a very small number of oocysts for infection is necessary and difficult to remove oocysts by conventional water filtration and are resistant to chlorination. The excessive watery diarrhea with cramping is self-limiting, as a rule, but can be severe and life-long in patients with AIDS. To diagnose an enzyme immunoassay is used for fecal antigens; a microscopic stool examination is less accurate and requires special techniques. In individuals without AIDS nitazoxanide is used. In people with AIDS Amebizide are ineffective, but the symptoms may subside when the immune system with ART improved.

Health Life Media Team

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