TALC IN THE LIVER OF PATIENTS WITH CHRONIC HEPATITIS-C INFECTION

Objectives: The presence of talc crystals in the liver has been associ ated with prior history of i.v. drug abuse (IVDA). Patients with hepat itis C virus (HCV) infection often deny IVDA, and many patients have n o other identifiable risk factors. To evaluate the role of prior surre ptitious IVDA in patients with chronic HCV infection and to assess the role of talc identification in liver tissue, an epidemiological evalu ation was performed. Methods: One hundred and nine patients with chron ic HCV (ALT abnormal > 6 months, HCV ELISA and recombinant immunoblot assay positive) underwent careful evaluation for risk factors potentia lly associated with HCV infection. All patients then had liver biopsy. Liver biopsies were reviewed by two observers to determine histologic al stage and were then examined by polarized light microscopy to revea l the presence or absence of typical talc crystals. Patients with disc ordance between history and histological findings were re-interviewed and were confronted with the information. Results: Patient interviews revealed the following risk factors: IVDA, 17.1%; blood transfusion, 2 4.3%; possible household/occupational exposure, 14.4%; and tattoos, 15 .3%. No identifiable risk factors were noted in 28.8% of the cohort. T alc crystals were seen in 9/109 (8.3%) of liver specimens. Of this gro up, only two patients admitted to prior history of IVDA. Seventeen pat ients with an IVDA history did not have identifiable talc crystals. Fo llow-up phone interviews were possible with five out of seven patients ,vith liver talc who had previously denied IVDA history. Of the five p atients, three admitted to prior IVDA but only after being confronted with the liver biopsy evidence. Conclusions: The findings of talc crys tals in liver biopsy specimens appears to be a specific, but not a sen sitive, marker for prior IVDA. Identification of talc crystals from li ver tissue may contribute to categorization of risk factors in patient s with community-acquired HCV infection. Tattoos are an important, and frequently unrecognized, risk factor for HCV infection. Despite these findings, a significant proportion of patients still have no identifi able risk factor for HCV acquisition.