safranine-t and Cryptosporidiosis

Despite the availability of many parasitological methods for detection of Cryptosporidium and Isospora (Cystoisospora) belli in fecal samples, there are uncertainties about the accuracy of these techniques in laboratory practice. In this study, 27 formalin-fixed positive stool samples for Cryptosporidium and 15 for I. belli were analyzed by 2 concentration methods, sedimentation by centrifugation (SC) and formalin-ethyl acetate (FE), and by 3 tintorial techniques, modified Ziehl-Neelsen (ZN), safranin (SF), and auramine (AR). No significant differences were observed on Cryptosporidium identification between concentration methods, while a significantly higher number of I. belli oocysts (P < 0.0001) was detected in fecal smears concentrated by the SC than by the FE method. Fecal samples processed by FE produced a median oocyst loss to the fatty ring of 34.8% for Cryptosporidium and 45.4% for I. belli. However, FE concentration provided 63% of Cryptosporidium and 100% of I. belli slides classified as superior for microscopic examination. Regarding the efficiency of staining methods, a more significant detection of Cryptosporidium oocysts was observed in fecal smears stained by ZN (P < 0.01) or AR (P < 0.05) than by the SF method. Regular to high-quality slides for microscopic examination were mostly observed in fecal smears stained with AR or ZN for Cryptosporidium and with SF or ZN for I. belli. This study suggests a great variability in oocyst power detection by routine parasitological methods, and that the most frequent intestinal coccidians in humans have specific requirements for concentration and staining.

Topics: Acetates; Acquired Immunodeficiency Syndrome; Benzophenoneidum; Centrifugation; Coloring Agents; Cryptosporidiosis; Cryptosporidium; Diarrhea; Feces; Fixatives; Formaldehyde; Humans; Indicators and Reagents; Isospora; Isosporiasis; Phenazines; Staining and Labeling

The present study was carried to explore the incidence of Cryptosporidium infection among lambs in Qalubia governorate as well as to study the ability of three staining techniques developed for rapid identification of Cryptosporidium oocysts in faecal samples of 120 neonatal lambs less than one month old. The stains used in this investigation were modified Zeihl-Neelsen stain (MZN), Safranin-methylene blue (SMB) and Giemsa stain (GS) to detect the recovered oocysts with their incidence variation. The diagnostic value was raised by direct smear and concentration floatation technique. The infection rates with Cryptosporidium oocysts among the investigated faecal samples from neonatal sheep were 82, 58, 36, out of 120 (68.3, 48.3 and 30%) by modified Zeihl-Neelsen stain, Safranin-methylene blue and Giemsa stain respectively. The lambs less than one week had higher infection rate. The relationship between age susceptibility and infection was discussed. The use of modified Zeihl-Neelsen stain was currently recommended procedure with the concentration floatation technique for the accurate diagnosis and rapid identification of Cryptosporidium oocysts.

Topics: Animals; Animals, Newborn; Azure Stains; Cryptosporidiosis; Cryptosporidium; Egypt; Feces; Incidence; Methylene Blue; Oocysts; Parasite Egg Count; Phenazines; Sheep; Sheep Diseases; Staining and Labeling

Cryptosporidium and isospora, two of the intestinal coccidian parasites known to be the causative agents of acute diarrhoea in animals, have now emerged as one of the main causes of prolonged life threatening diarrhoea in immunocompromised patients particularly so in patients with AIDS. Between June 1996 and December 1997, a total of 75 immunocompromised patients presenting with diarrhoea were investigated both for Cryptosporidium and Isospora. The study group consisted of cancer and AIDS patients with history of diarrhoea. Cryptosporidium oocysts were detected in 35 patients (46.7%). One of the faecal samples from an AIDS patient with diarrhoea showed the presence of both Cryptosporidium and Isospora oocysts. To the best of our knowledge, this is the second documented report of Isospora associated diarrhoea in an AIDS patient from India. The various techniques used for demonstration of these parasites were modified acid fast staining, Safranine Methylene-blue staining and direct immunofluorescence test.

Topics: Acquired Immunodeficiency Syndrome; Adult; Aged; Animals; Coccidiosis; Coloring Agents; Cryptosporidiosis; Diarrhea; Feces; Female; Fluorescent Antibody Technique, Direct; Humans; Immunocompromised Host; Isospora; Male; Methylene Blue; Middle Aged; Neoplasms; Phenazines

Infection by cryptosporidium causes acute or chronic diarrhea in immunocompetent or immunosuppressed patients respectively. We compared the Ziehl-Nielsen and the safranine stains in 604 stool samples from children with acute diarrhea. Sensitivity for safranine (96%) and for Ziehl-Nielsen (88%) was not significantly different. Given the simplicity and low cost of the safranine stain, this is proposed as a routine method for the investigation of infection by cryptosporidium.

Topics: Child; Cryptosporidiosis; Diarrhea; Feces; Humans; Phenazines; Staining and Labeling

Features are described of a new staining method for the detection of Cryptosporidium oocysts in faeces. Smears, fixed in acid-methanol, are stained with heated safranin and counterstained with methylene blue. Oocysts stain a vivid orange-pink and are easily recognized. The method is rapid and simple with little source of error. The method is more sensitive than currently recommended Ziehl-Neelson methods; of 26 cases of cryptosporidiosis diagnosed by the new method only 19 were detected by acid-fast and only 11 by acid-alcohol-fast methods. Oocysts can be stained by safranin-methylene blue after concentration by various methods, in paraffin-embedded material, and after storage for months at various temperatures.

Topics: Animals; Child; Cryptosporidiosis; Cryptosporidium; Feces; Humans; Methylene Blue; Parasite Egg Count; Phenazines; Staining and Labeling

Cryptosporidium oocysts were present in 20 (10.4%) of 193 Rwandese children and in 3 (3.0%) of 100 adults with diarrhea. In four of the children and in one adult, Cryptosporidium was associated with other enteric pathogens. The higher incidence of Cryptosporidium in diarrheic children was statistically significant. The parasite was not found in 94 formed stools submitted for parasitological examination. The mean age of the Cryptosporidium-positive children was 13.3 months. In four children, Cryptosporidium was associated with severe malnutrition. All of those required rehydration, and one child died as a direct consequence of severe diarrhea. The three adult patients showed no recognizable immunodeficiency, and their diarrhea resolved spontaneously. Staining with 1% safranin was not only more simple and rapid but also more sensitive than the modified Ziehl-Neelsen technique.

Topics: Adolescent; Adult; Africa, Central; Animals; Child; Child, Preschool; Coccidia; Cryptosporidiosis; Cryptosporidium; Diarrhea; Feces; Female; Humans; Infant; Male; Phenazines; Staining and Labeling