*not applicable
HB: hemoglobin
MCV: mean corpuscular volume
MCH: mean corpuscular hemoglobin
PBS: peripheral blood smear
BM: bone marrow
LDH: lactate dehydrogenase
BUN: blood urea nitrogen
Cr: creatinine
Impairment of the hematological system is one of the earliest signs of lead accumulation and could be characteristic. Even in milder cases of lead exposure, anemia may be the only obvious abnormality (5). Obviously, the PBS is the fastest, simplest and cost-effective test which could also be made and examined at emergency and screening rooms at hospitals and could prevent unnecessary laboratory tests and other invasive diagnostic procedures including inappropriate laparatomy(13). Since this process is among the most time-consuming ones in hematology laboratories and requires high technical competence to minimize the errors of subjectivity, each laboratory should make its own policy to review the blood smears. Clearly providing clinical data including occupational and environmental health history through communication between the clinicians and the laboratory team could lead to a more rapid and accurate diagnosis(14).
Our patient was a case of chronic lead poisoning with atypical symptoms and signs, such as severe bone pain and highly elevated liver enzymes which caused delayed diagnosis. In this case, a lot of laboratory and imaging work ups including hematologic tests (and also the initial PBS) failed to reach a correct diagnosis, while the second PBS review by an expert clarified the long and painful story. We believe that even the first PBS review may discover the problem if it is reviewed accurately and/or is provided with typical clinical data.