Comparison of 2 dyes in the detection of Pneumocystis carinii
Casanova-Cardiel, L.J.; Cedillo-Rivera, R.; Garduño-Rodríguez, G.; Muñoz, O.
Revista de Investigacion Clinica; Organo del Hospital de Enfermedades de la Nutricion 48(6): 443-447
1996
ISSN/ISBN: 0034-8376 PMID: 9132888 Document Number: 466206
To evaluate two staining procedures used in the detection of P. carinii. Bronchoalveolar lavage samples were obtained from 20 immunosupressed rats. The samples were stained by three procedures: o-toluidine blue (OTB), Diff Quik (DQ), and a silver stain as the gold standard. The microscopic search for P. carinii was made independently by two observers. Fifteen of the 20 samples were positive to P. carinii with the silver stain. The sensitivity with DQ was 27% and the specificity 100%. With OTB the sensitivity was 93% and the specificity was 80%. The inter-raters' agreement by kappa was 0.11 for DQ and 0.53 for OTB. Our results suggest that the silver stain should be used for an adequate diagnosis of pneumonia caused by P. carinii.