Mindray Bc-6900 Scattergram Analysis Combined With Peripheral Blood Smear In The Diagnosis Of T. Marneffei Infection In An Hiv-Positive Patient: A Case Report

Background: Rapid and accurate diagnosis of HIV-positive patients with Talaromyces marneffei (T. marneffei) infections remains challenging. A 60-year-old woman came to our inpatient department presenting with hematuria, abdominal pain, and diarrhea for one week. The patient had a past medical history of Acquired Immune Deficiency Syndrome (AIDS). The patient's stool was watery and the color of soy sauce. The patient was without fever, cough, and skin lesions.Methods: The blood routine was performed with a Mindray BC-6900 hematology analyzer.Results: Blood routine showed leukocytosis with neutrophilia and basophils and the WBC/DIFF scattergram showed a cluster of neutrophils connected with a monocyte and lymphocyte cluster and an additional cluster of immature granulocytes and heterotypic lymphocytes or primitive cells. Surprisingly, the peripheral blood film evaluation revealed small round-to-ovoid yeast cells within the cytoplasm of neutrophils. A T. marneffei infection was suspected and anti-fungal therapy was initiated. The patient's diarrhea improved after treatment with amphotericin B for two days. A second blood routine showed a normal number of leukocytes and basophils and a diminished cluster of immature granulocytes and heterotypic lymphocytes or primitive cells. After one week, blood cultures had grown T. marneffei.Conclusions: The WBC/DIFF scattergram obtained from a Mindray BC-6900 analyzer provided significant hints to enhance diagnosis of T. marneffei when combined with results of a peripheral blood smear.