Case Study Two:
The patient is a 10 year-old boy from Florida who developed abdominal pain while on a skiing trip with his family in Colorado. He was brought to the emergency department of a Denver hospital where a complete blood count (CBC) was ordered. These results were obtained:
| WBC | 18.5 x 109/L | 3.2 - 9.8 x 109/L |
| RBC | 5.45 x 1012/L | 4.50 - 5.70 x 1012/L |
| Hemoglobin | 16.0 g/dL | 13.6 - 17.2 g/dL |
| Hematocrit | 48.2% | 35 - 49% |
A manual differential performed as part of the CBC revealed that more than 70% of the segmented neutrophils had bi-lobed or mono-lobed nuclei; the cells with bi-lobed nuclei had two round segments of nearly equal size, connected by a thin chromatin strand, as seen in this representative field. The nuclei in some other cells were mono-lobed and peanut shaped, slightly indented, or round, leading to confusion as to whether to classify them as segmented or band neutrophils. The chromatin appeared fully mature and parachromatin was evident. No toxic granulation was observed. What is the most likely cause for the nuclear morphology that is seen demonstrated in the image shown here?
Please select the single best answer
