BLINDED, EXTERNALLY CONTROLLED MULTICENTER EVALUATION OF LIGHT-MICROSCOPY AND PCR FOR DETECTION OF MICROSPORIDIA IN STOOL SPECIMENS

The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where t echnicians used light microscopy and for six laboratories where techni cians used PCR. The average overall sensitivities were 67% (89% for pa tient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities wer e 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used.