• A 10-year-old girl was first seen at age 5 years with pneumonia and neutropenia. Since then, she has remained leukopenic, although manifesting a leukocytosis only when she has pulmonary infection. A rapid fall in her peripheral WBC count occurs with initiation of antibiotic therapy. Despite her neutropenia, marked myeloid hyperplasia is evident on marrow smear examination; many cells being hypersegmented with fine intralobular bridging with chromatin strands and cytoplasmic vacuolation. The peripheral WBC response to epinephrine administration did not indicate a shift from the circulating to marginal neutrophil pool. Results from a Rebuck skin window test suggested poor neutrophil tissue migration. A defect in granulocyte release from the patient's marrow may explain these bizarre hematologic findings.
(Am J Dis Child 131:655-658, 1977)
O'Regan S, Newman AJ, Graham RC. 'Myelokathexis': Neutropenia With Narrow Hyperplasia. Am J Dis Child. 1977;131(6):655–658. doi:10.1001/archpedi.1977.02120190049011
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