Modified acid fast staining: a better diagnostic tool in chronic diarrhoea due to cryptosporidiosis.

Cryptosporidium parvum is an emerging pathogen responsible for chronic diarrhoea in children and immuno-compromised individuals,especially aids patients. currently,there is no effective therapeutic strategy for treating cryptosporidiosis,therefore control and supportive treatment of cryptosporidiosis depends upon rapid and accurate diagnosis of this infection. a descriptive study was conducted in the pathology department of khyber medical college and pathology laboratory of khyber teaching hospital over a period of one year march 2007-april 2008. a total of 200 stool samples were tested for the presence of c. parvm oocysts from children < 5 years age suffering from diarrhoea for > 5 days. total and differential leukocyte count was determined to assess immune status of the patients. modified ziehl-neelsen (z-n) staining,a rapid,sensitive and easy test,was used successfully for the detection of c. parvum oocysts in stool specimen. cryptosporidium oocysts were found in 18 (9.0%) samples. out of 18 positive cases,13 (72.2%) children had lymphopenia hence their immune status was impaired. infection was common in children between 1-24 months of age. mean duration of diarrhoea was 11 months. most of c. parvum infected children were consumers of well water (77.8%). cryptosporidiosis,although a self-limiting disease,rarely investigated routinely,can become chronic and life threatening in immuno-compromised individuals. majority of affected patients are immune-compromised. modified z-n is a sensitive and rapid method which can explore the gravity of this infection even further if used routinely and may control morbidity and mortality associated with this infection.