Reduction in neutrophil count during hepatitis C treatment: drug toxicity or predictor of good response?

BACKGROUND: Bone marrow suppression is a well-recognized toxicity of the treatment of hepatitis C virus (HCV). Reduction of the peginterferon dose because of neutropenia is common in clinical practice. However, reduction of peginterferon dose during the first weeks of HCV treatment is associated with failure to achieve sustained virological response.

AIMS: The objective of this study is to investigate whether the fall of neutrophil count during hepatitis C treatment is associated with achieving sustained virological response.

METHODS: We performed an observational study of patients who completed peginterferon and ribavirin treatment in an Infectious Diseases Department in Manchester, UK.

RESULTS: Of the 74 patients included in the analysis, 78% had genotype 2 or 3 hepatitis C and 15% had liver cirrhosis. Sustained virological response was achieved in 78% of patients. On univariate analysis, factors related to achieving sustained virological response were younger age, genotype 2 or 3, baseline neutrophil count, and fall of neutrophil count during treatment. Multivariate analysis showed baseline neutrophil count >3.5 x 10(3) cells/mm(3) [odds ratio (OR) 5.7; 95% confidence interval (CI) 1.24-26.3] and a reduction of neutrophil count >60% (OR 4.5; 95% CI 1.03-19.9) to be independently associated with achieving sustained virological response. Neutropenia was not associated with an increased risk of infections.

CONCLUSIONS: In this observational study, higher baseline neutrophil count and fall of neutrophil count during the treatment of hepatitis C was associated with achieving sustained virological response. These findings could have important implications for the monitoring and management of HCV treatment with peginterferon if they are confirmed in other studies.