       Document 0629
 DOCN  M9550629
 TI    Cryptosporidium antigen detection in human feces by reverse passive
       hemagglutination assay.
 DT    9505
 AU    Farrington M; Winters S; Walker C; Miller R; Rubenstein D; Clinical
       Microbiology and Public Health Laboratory, Addenbrooke's; NHS Trust,
       Cambridge, United Kingdom.
 SO    J Clin Microbiol. 1994 Nov;32(11):2755-9. Unique Identifier : AIDSLINE
       MED/95155595
 AB    A reverse passive hemagglutination (RPH) assay was developed for
       Cryptosporidium oocyst antigen with an antioocyst monoclonal antibody
       (MAb; MAb-C1) coupled to stabilized sheep erythrocytes. RPH was compared
       with microscopy of auramine-phenol-stained smears of 56 oocyst-positive
       fecal samples, each of which was tested blindly by RPH with two
       oocyst-negative samples received on the same day (a total of 112
       controls). Thirty-nine additional fecal samples from human
       immunodeficiency virus type 1 antibody-positive patients with diarrhea
       (10 of which were positive in auramine-phenol-stained smears) were
       stored at -20 degrees C before testing. Thirty specimens with a variety
       of other fecal pathogens (all negative for oocysts) were also tested. Of
       the 237 samples tested, 69 were positive by one or both methods: 65 by
       RPH and 66 by microscopy. The kappa coefficient of agreement between the
       methods was very high at 0.926. The sensitivity of RPH was 93.9%, the
       specificity was 98.2%, the positive predictive value was 95.4%, and the
       negative predictive value was 97.7%. Visible oocyst numbers and RPH
       titers were measured after storage of fecal samples and oocyst
       concentrates for 8 days at 4 degrees C. Oocyst morphology was generally
       poor in specimens from the human immunodeficiency virus type 1
       antibody-positive group, and it degenerated during the 8-day storage
       experiments. MAb-C1-reactive antigen eluted from oocysts to give
       progressively higher reciprocal titers during storage, and it was
       partially removed from the oocysts by concentration. RPH is a promising
       technique for the detection of Cryptosporidium antigen in human feces
       and may be useful when specimens are stored before testing.(ABSTRACT
       TRUNCATED AT 250 WORDS)
 DE    Adolescence  Adult  Animal  Antigens, Protozoan/*ANALYSIS  Child  Child,
       Preschool  Cryptosporidium/*IMMUNOLOGY  Feces/*PARASITOLOGY
       Hemagglutination Tests  Human  HIV Antibodies/ANALYSIS  Infant  Parasite
       Egg Count  Support, Non-U.S. Gov't  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

