#00060753

A 6 year old boy was referred with a leukocyte count of 125000/µl and a differential WBC count of monocyte 8%, eosinophil 15%, 7% atypical lymphocyte and a slight toxic granulation of neutrophils. Peripheral blood smears (PBS) examination revealed a large cell with abundant cytoplasm with numerous diplococcus bacterium. Two  other large cells with abundant cytoplasm that morphologically were consistent with epithelial cells (Figure 1) were also found.  Review of the smear failed to find phagocytic cells containing bacteria.A repeat blood smear failed to show bacteria.   It seems that the source of diplococcus loaden cell was patient’s skin epithelial cells contaminating the blood sample.  Careful examination can prevent the misdiagnosis of bacteremia and  inappropriate treatment.