Impairment of neutrophil antifungal activity against hyphae of Aspergillus fumigatus in children infected with human immunodeficiency virus.

Human immunodeficiency virus (HIV)-infected patients may acquire invasive aspergillosis without previously recognized risk factors, such as neutropenia or corticosteroid therapy. Because neutrophils (PMNL) are an important component of host defense in aspergillosis, the antifungal activity of PMNL against hyphae of Aspergillus fumigatus in 31 HIV-infected children was assessed. Hyphal damage was unaffected in 15 HIV-infected children with age-adjusted CD4 cell counts > or = 25% of the normal median value; it was decreased in 16 with CD4 cell counts < 25% (both vs. 20 healthy controls, P = .001. Incubation with sera from 12 of 14 HIV-infected children but not with the recombinant HIV proteins gp120, gp41, and p24 suppressed antifungal activity of normal PMNL compared with normal serum (P = .002). Pretreatment of defective PMNL from 5 patients with granulocyte colony-stimulating factor (G-CSF) partially corrected the defect (P = .002). These findings suggest that impaired serum-mediated antifungal activity against Aspergillus hyphae exists in PMNL of HIV-infected patients with low CD4 cell counts; G-CSF may improve this activity.