Parasites and Biliary stones

Cryptosporidiosis ٥٥
present. The respiratory tract also is a possible site of infection; however,
the clinical presentation may be relatively nonspecific. In addition, most
of the immunocompromised patients that were diagnosed with this form
of cryptosporidiosis via bronchial lavage had a concurrent infection with
cytomegalovirus (CMV) or Pneumocystis carinii (Mandell et al., 2000).
Diagnosis:
The “gold standard” for detecting Cryptosporidium oocysts in stool
was a modified acid-fast stain of a fecal smear. However, the sensitivity
for the detection of Cryptosporidium is better with enzyme-linked
immunosorbent- based immunoassay formats or immunofluorescent
assays that facilitate the visualization of fecal oocysts (Katanik et al.,
2001).Polymerase chain reaction (PCR) nucleic acid amplification for
detection of Cryptosporidium oocysts also has been used as a research
tool in both environmental and fecal samples. In addition to increased
sensitivity, PCR can provide genotype and sequence information
important for epidemiologic studies (Robinson et al., 2003). These tests
hold agreat promise but are not standardized yet for routine clinical use.
Other experimental methodologies include 2-color, flow cytometry and
colorimetric detection systems. The 2-color flow cytometry provides
better sensitivity than do any other assays for the quantitation of oocysts
(Moss and Arrowood, 2001).
As this is a non-inflammatory diarrhea that has both a malabsorptive
and secretory component, levels of serum B12, stool fat, d-xylose
adsorption, and electrolytes should be measured. In biliary disease,
alkaline phosphate, gamma-glutamyl transferase, and bilirubin levels may
be elevated. Imaging studies are not indicated as a first-line diagnostic
approach. Abdominal radiographs and computed tomography (CT) scans
are non-specific and may show distended loops of bowel or air fluid