Abstract
A number of disorders for which an association with hepatitis C virus infection exist. These disorders include essential mixed cryoglobulinemia, membranoproliferative glomerulonephritis, and idiopathic pulmonary fibrosis. This study was initiated to investigate the cellular content and lymphocyte subpopulations of bronchoalveolar lavage fluid obtained from individuals with chronic hepatitis C and to compare the results to those of controls. Eighteen patients with chronic hepatitis C (male/female, 6/12) and 14 healthy volunteers (male/female, 6/8), were studied. Bronchoalveolar lavage fluid was obtained from each; and the lymphocyte subtypes and the presence of HCV‐RNA in the bronchoalveolar lavage fluid were determined. All anti‐HCV positive subjects were HCV‐RNA positive in serum. One (5.6%) had a HCV‐RNA positive bronchoalveolar lavage. The total cell and neutrophil counts of the bronchoalveolar lavage fluid were significantly greater in patients with chronic hepatitis C as compared to controls (5,799.6 ± 957.4 × 10^3^/ml vs. 1,835.7 ± 447.8 × 10^3^/ml, P = 0.001; 1,175.8 ± 634.7 × 10^3^/ml vs. 53.1 ± 28.1 × 10^3^/ml, P = 0.029). In contrast, the lymphocyte, macrophage and eosinophil counts did not differ. No difference in the percentage, median or range of individual T cell subsets or B cell numbers in the bronchoalveolar lavage fluid existed between the groups. It is concluded that hepatitis C virus infection may be associated with an occult pulmonary inflammatory reaction manifested by an increased number of polymorphonuclear neutrophils in bronchoalveolar lavage fluid. This finding may contribute to the process that leads to idiopathic pulmonary fibrosis seen in a minority of cases of chronic hepatitis C. J. Med. Virol. 66:34–39, 2002. © 2002 Wiley‐Liss, Inc.