And the Oscar goes to peripheral blood film for detection of lead poisoning in a complicated patient: A case report with review of laboratory clues

Abstract Background Peripheral blood smear examination is an invaluable laboratory test which provides the complete hematologic and/or non-hematologic picture of a case. In addition to verifying the results of automated cell counters, it has the potential to identify some pathologic morphologic changes that remain hidden using the cell counters alone. Case presentation A 40-year-old man with a 3 year history of alcohol intake and marijuana abuse presented with severe lower extremities bone pain and abdominal pain. Physical examination showed high blood pressure, high pulse rate and abdominal tenderness. He underwent extensive laboratory and imaging tests, and cholecystectomy and bone marrow study, without any definite diagnosis or improvement. Right after all these invasive, expensive and time consuming investigations during a month, finding a point on the peripheral blood smear by an expert led to the final diagnosis. The finding was coarse basophilic stippling in the red blood cells. Elevated blood lead level and the presence of ring sideroblast in the bone marrow study confirmed the diagnosis of lead poisoning and the patient responded well to chelator therapy in a short period. Conclusion This case clearly shows the value of peripheral blood smear review and its impact on the patient care. In order not to lose the cases, laboratories are recommended to design their own policy for peripheral blood smear review. Peripheral blood smear is the fastest, simplest, and most available screening test which could prevent many misdiagnoses and malpractices. It provides rich morphological information, among which basophilic stippling is highly suggestive of lead poisoning.