"Idiopathic neutropenia" in very low birthweight infants.
We employed a standardized investigative approach to evaluate four cases of "idiopathic neutropenia" in very low birthweight infants. The evaluation included maternal anti-neutrophil antibodies, a marrow aspiration, and a three-day trial of recombinant granulocyte colony-stimulating factor (rG-CSF). All patients had neutropenia at or shortly following delivery, and remained neutropenic (generally <500/microl) for 1-9 weeks until rG-CSF was administered. Blood and bone marrow studies in all 4 indicated that the neutropenia was: (i) the kinetic result of diminished neutrophil production; (ii) not alloimmune; (iii) not cyclic; and (iv) not associated with recognized inborn errors, bacterial or viral infections, or medications. All responded to rG-CSF by transiently increasing their blood neutrophils to normal, and the neutropenia resolved in all cases with time. It is likely that "idiopathic neutropenia" in this population represents a common phenotype of several different causes, rather than a single entity. Some cases, perhaps the majority, will respond to a short course of rG-CSF administration.
Juul
S E
SE
Department of Pediatrics, University of Florida College of Medicine, Gainesville 32610-0296, USA.
Calhoun
D A
DA
Christensen
R D
RD
D004200:Diseases in Twins; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000627:therapeutic use*; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000188:drug therapy; D008297:Male; D009503:Neutropenia / Q000188:drug therapy; D011994:Recombinant Proteins; D016896:Treatment Outcome; D014310:Triplets; D014427:Twins
D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor