Diff-Quik stain as a simplified alternative to Papanicolaou stain for determination of quality of endocervical specimens submitted for PCR detection of Chlamydia trachomatis

The simple, rapid, two-step Diff-Quik stain procedure (Baxter Diagnostics) was compared with the Papanicolaou stain for microscopic determination of endocervical specimen quality. Results from 230 (98.7%) of 233 specimens stained by both methods indicated agreement between the two staining methods for detection of the endocervical cells or erythrocytes indicating specimen adequacy. By using the Amplicor Chlamydia trachomatis Test (Roche Diagnostic Systems) to detect C. trachomatis and the Diff-Quik stain to assess specimen adequacy, PCR-positive results were obtained from 147 (9.1%) of 1,615 microscopically adequate specimens but from only 13 (2.2%) of the 583 inadequate specimens (P < 0.001).