A clinical and virological study of hepatitis C virus-related cryoglobulinemia in Germany.
OBJECTIVE
Several reports, especially from Southern Europe, have demonstrated a close association between hepatitis C virus (HCV) infection and mixed cryoglobulinemia. In this study we have analyzed the significance of HCV-related cryoglobulinemia in Germany.


METHODS
Sera from 79 patients with cryoglobulinemia of type I (n=21), II (n=28) or III (n=30) were investigated for HCV markers. Furthermore, 132 consecutive patients with chronic hepatitis C were studied for the presence of cryoglobulins. Genotypes of HCV were determined according to Simmonds, and HCV-RNA concentrations were measured in patients with and without cryoglobulinemia.


RESULTS
In 79 patients with cryoglobulinemia we found anti-HCV antibodies in 17 (22%) and HCV-RNA in 11 patients (14%). HCV antibodies were more frequent in essential (44%) compared to secondary mixed cryoglobulinemia (15%). In 132 patients with chronic HCV infection cryoglobulins were detected in 37 patients (28%), in 21 of them at low levels. Clinical symptoms due to cryoglobulinemia were observed in eight of the 37 patients, severe vasculitis in three patients with high cryocrit-levels and cryoprecipitation at room temperature. HCV genotype 1 and subtype 1b were most prevalent, both in patients with and without cryoglobulinemia, and mean HCV-RNA levels were not different between the two groups. Comparison of HCV-RNA levels in cryoprecipitates, supernatant and native serum suggests binding of HCV-RNA to the cryoprecipitate with different affinity in individual patients.


CONCLUSIONS
The lower prevalence of HCV-related cryoglobulinemia in our study compared with data from Italy and France suggests a south-north gradient in the prevalence of HCV-associated cryoglobulinemia in Europe.
Division of Rheumatology and Clinical Immunology, University Hospital of Freiburg, Germany.
S M
SM
Weiner
T
T
Berg
H
H
Berthold
S
S
Weber
T
T
Peters
H E
HE
Blum
U
U
Hopf
H H
HH
Peter
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000373:Agglutinins / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001809:Blood Viscosity; D015933:Complement C3d / Q000032:analysis; D003449:Cryoglobulinemia / Q000453:epidemiology / Q000821:virology*; D005260:Female; D005838:Genotype; D005858:Germany / Q000453:epidemiology; D016174:Hepacivirus / Q000302:isolation & purification; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012217:Rheumatoid Factor / Q000097:blood; D019562:Viral Load
D000373:Agglutinins; D015415:Biomarkers; D015933:Complement C3d; D012217:Rheumatoid Factor