Cryptosporidium
Dongyou Liu in Handbook of Foodborne Diseases, 2018
Humans can acquire cryptosporidiosis through several transmission routes, such as direct contact with infected persons (anthroponotic transmission) or animals (zoonotic transmission), and consumption of contaminated water (drinking or recreational) or food.7 The major public health importance of Cryptosporidium lies in the potential for outbreaks to occur when drinking water, recreational water, or food becomes contaminated with infectious Cryptosporidium oocysts.8 Numerous aspects of the biology of Cryptosporidium render the parasite particularly suited to foodborne and/or waterborne transmission. These include (1) the parasite's resistance to disinfection, including by chlorine9,10; (2) its ability to be shed in very large quantities, for example, infected neonatal calves can excrete up to 30 billion oocysts or more over a 1–2 week period11; (3) the low infectious dose (10–100 oocysts)12–14; and (4) the long incubation period of cryptosporidiosis (averaging 7 days),7 which delays the identification of the source and implementation of interventions to prevent transmission.
Overview of HIV Infection
Mark J. Rosen, James M. Beck in Human Immunodeficiency Virus and the Lung, 1998
The diagnosis of cryptosporidiosis is established by identifying the oocyst in stool or bronchial secretions. Cryptosporidia can easily be overlooked owing to their small size (4- to 5- µm oocysts) during routine stool examination for ova and parasites, or can easily be mistaken for yeast. Many stains have been employed to make the identification easier. Modified acid-fast stains stain the oocysts red, whereas yeasts will stain blue-green. A modified cold Kinyoun's stain gives a similar staining pattern (2,6). The modified Sheather's sugar flotation procedure is a concentration technique that increases the diagnostic sensitivity in nonliquid stool specimens. Immunological studies have shown that anticryptosporidium IgM, IgG, and IgA develop within 3 months of infection with Cryptosporidium spp., but may persist for various lengths of time; however, their presence does not clearly correspond to the severity of infection (2). Commercially available tests for use in research, such as a monoclonal antibody to the cryptosporidial oocyst wall, or an enzyme-linked immunosorbant assay (ELISA) with a soluble Cryptosporidium-specific antigen, have seen little diagnostic use in the clinical setting (1). The foregoing staining procedures have been used successfully in the examination of bronchial secretions in patients presenting with pulmonary symptoms, often in association with other pathogens, such as P. carinii and cytomegalovirus (6-8).
Cryptosporidium
Dongyou Liu in Laboratory Models for Foodborne Infections, 2017
Traditional method for diagnosing human intestinal cryptosporidiosis is based on microscopic detection of Cryptosporidium oocysts in stool samples with acid-fast, auramine, or indirect immunofluorescence stains. Use of fluorescence microscopy (e.g., light-emitting diode light sources) together with fluorescent stains (e.g., auramine-rhodamine, which makes oocysts appear yellow-orange) provides a more sensitive detection than the modified acid-fast stain [e.g., modified Ziehl–Neelsen (hot) or Kinyoun (cold), which demonstrates the acid resistance of oocysts]. Further, application of formalin-ether or formalin-ethyl acetate sedimentation concentration procedures, or Sheather’s flotation-concentration method (using a sucrose gradient) improves the sensitivity of microscopic detection. Nonetheless, Cryptosporidium oocysts (of 4–6 µm in diameter) must be differentiated from other partially acid-fast organisms (e.g., Cyclospora cayetanensis) and other similar looking yeast or fungal spores [23,24].
Traditional practices and childhood cryptosporidiosis in Nigeria: A review
Published in Alexandria Journal of Medicine, 2018
Adekunle B. Ayinmode, Oluwasola O. Obebe
Cryptosporidium infection is known worldwide as an important aetiology of diarrhoea in both immunocompromised and immunocompetent individuals.5,6 In the developed and developing countries, cryptosporidiosis occurs more often in infants and children than in adults.7,8 The infection is transmitted to the susceptible host via the fecal-oral route from the consumption of food and water contaminated with oocyst from an infected host.9 Other suggested sources of Infection include contact with infected humans, animals, and contaminated recreational waters.10–12 Cryptosporidiosis is characterised by a self-limited diarrheal illness in healthy individuals but may cause chronic diarrhoea that may be fatal to infants and individuals with compromised immune systems, such as persons with HIV/AIDS.13 In children, cryptosporidiosis is mainly characterised by watery diarrhoea that can persist for up to 12 weeks and this condition is usually fatal in malnourished children.14–17
Prevalence and associated risk factors of intestinal parasitic infections in Kurdistan province, northwest Iran
Published in Cogent Medicine, 2018
Fares Bahrami, Ali Haghighi, Ghasem Zamini, Mohammad Bagher Khadem-Erfan, Eznolla Azargashb
Cryptosporidiosis has been observed in five cases (0.36%) of all the studied subjects and 1.7% in the positive cases. In Shiraz, Iran, a prevalence of 10.8% has been reported (Mirzaei, 2007), which is higher compared with our result. In another study performed in New Zealand, a prevalence rate of cryptosporidiosis was higher in rural areas compared with urban areas (Snel et al., 2009). And cryptosporidiosis was also reported to be more common during late summer than the other seasons (Painter et al., 2015). Similarly, our results confirm that 80% of positive cases for cryptosporidiosis were diagnosed in summer, 20% in the middle of autumn, and 60% (3 of 5) were from rural areas in patients who had contact with domestic animals and who obtained water from wells and springs (Table 3). These findings have indicated that the summer, untreated water, contact with animals and job (farmer) are significant predictors for cryptosporidiosis (Table 4).
Maryland ACP Mulholland Mohler winning resident abstracts 2018
Published in Journal of Community Hospital Internal Medicine Perspectives, 2018
Maryellen Woodward
A 62-year-old female with AIDS (CD4 40) not on HAART and hepatitis C presented with diarrhoea for 2 months and was also found to be in acute hypoxemic respiratory distress. Physical examination was unremarkable other than HIV-associated wasting syndrome. Based on laboratory findings and radiographic data, TMP-SMX prednisone were started due to a high suspicion for severe Pneumocystis jirovecii pneumonia (PCP). PCP was confirmed by bronchoalveolar lavage. Stool testing confirmed cryptosporidiosis. Diarrhoea was managed supportively and did not persist beyond day 2 of hospitalization. On day 4 of hospitalization, she developed hypoglycaemia with blood glucose in the 40s. A supplemental dextrose infusion, multiple dextrose ampules, carbohydrate-rich food, and glucagon were ineffective. TMP-SMX was discontinued and replaced by clindamycin and primaquine for treatment of PCP. Normoglycaemia was achieved and maintained without supplemental dextrose 24 h following the last administered dose of TMP-SMX. Cortisol level was normal and C-peptide level was elevated at 7.78 ng/mL, suggesting that the hypoglycaemia was due to increased endogenous insulin secretion.
Related Knowledge Centers
- Cryptosporidium
- Ileum
- Immunocompetence
- Parasitic Disease
- Parasitism
- Respiratory Tract
- Immune System
- Autoimmune Disease
- Immunodeficiency
- HIV/AIDS