Evaluation of a manual technique for detection of neutropenia and thrombocytopenia in dogs receiving chemotherapy

OBJECTIVE: To determine accuracy of a manual technique for detection of neutropenia and thrombocytopenia in dogs receiving chemotherapy. DESIGN: Masked prospective study. ANIMALS: 11 dogs treated with chemotherapy for neoplasia. PROCEDURE: 124 blood samples from dogs being treated with chemotherapy for various neoplasms were processed through an automated cell counter, and results were compared with those obtained by use of a rapid manual technique for estimating neutrophil and platelet concentrations to determine whether the manual technique could accurately detect dogs with neutropenia or thrombocytopenia. RESULTS: By use of automated techniques, neutropenia (< 3,000 cells/microl) was detected in 17 of 124 blood samples, and thrombocytopenia (< 100,000 platelets/microl) was detected in 3 of 124 blood samples. The manual technique correctly identified 16 of 17 (94%) blood samples with neutropenia, with a specificity of 92% (98/107). The manual technique correctly identified 3 of 3 (100%) blood samples with thrombocytopenia, with specificity of 94% (114/121). CONCLUSIONS AND CLINICAL RELEVANCE: Manual estimates of neutrophil and platelet counts are sensitive and specific; however, a full differential cell count is still preferable.