Study of Cough Reflex Sensitivity in a Group of Egyptian Patients with Chronic Hepatitis C Virus Infection

Objective: The aim of this work was to study the effect of chronic hepatitis C viraemia on cough reflex sensitivity.Material and Method: Cough reflex sensitivity was tested by Capsaicin cough provocation in 57 patients (33.66±6.809 years old [M±SD]) with chronic HCV infection. Patients were divided into 3 subgroups: group I: 22 with normal Alanine aminotransferase (ALT) and no evidence of liver cirrhosis on ultrasound, group II: 19 with elevated ALT and active hepatitis but no cirrhosis on liver biopsy (8 on treatment) and group III: 16 with elevated ALT and positive cirrhosis on liver biopsy (6 on treatment). 23 normal age matched subjects were tested as controls. Results: log C5 was significantly lower in the three groups of patients than controls (p<0.05). Patients with liver cirrhosis showed a significantly lower log C5 than those without cirrhosis and normal ALT (p <0.05). No significant difference was found between the two groups with high ALT or the two groups without cirrhosis (p>0.05 for both). Females showed significantly lower log C5 values than males in normal controls but not in patients (p<0.05 and p>0.05 respectively. Patients on interferon therapy showed a significantly lower log C5 values than untreated patients (p<0.01). In all patients, the relation between viral load (RNA PCR) and provocative concentration of capsaicin was inverse and significant (r=-0.717, p<0.001). Conclusion: Both hepatitis C viraemia and interferon therapy enhance cough sensitivity in chronic hepatitis C patients and more studies are needed to explain how this occurs.