Thyroid involvement in patients with overt HCV-related mixed cryoglobulinaemia.
BACKGROUND
Mixed cryoglobulinaemia (MC), a systemic vasculitis associated with hepatitis C virus (HCV) infection in >90% of cases, is frequently complicated by multiple organ involvement. The prevalence of thyroid disorders in MC has not yet been studied.


OBJECTIVE
To investigate the prevalence and clinical features of thyroid involvement in patients with HCV-associated MC (HCV + MC).


METHODS
Case-control study.


METHODS
HCV + MC patients (n = 93, 17 men and 76 women, mean +/- SD age 63 +/- 10 years, mean disease duration 14 +/- 7 years) consecutively referred to the Rheumatology Unit were matched by sex and age (+/- 2 years) to (i) 93 patients with chronic C hepatitis (CH) without MC and (ii) 93 healthy (HCV-negative) controls from the local population. Measurements included prevalence of hypo- or hyperthyroidism, thyroid autoantibodies, thyroid nodules and thyroid cancer.


RESULTS
By McNemar's chi(2) test, the following thyroid abnormalities were significantly more frequent in HCV + MC patients than in HCV-negative controls: serum anti-thyroperoxidase autoantibody (AbTPO) (28% vs. 9%, p = 0.001); serum AbTPO and/or anti-thyroglobulin autoantibody (31% vs. 12%, p = 0.004); subclinical hypothyroidism (11% vs. 2%, p = 0.038); thyroid autoimmunity (35% vs. 16%, p = 0.006). Serum AbTPO were also significantly more frequent in HCV + MC patients than in CH controls (28% vs. 14%, p = 0.035).


CONCLUSIONS
The prevalence of thyroid disorders is increased in patients with HCV-related mixed cryoglobulinaemia. We suggest careful monitoring of thyroid function in these patients.
Antonelli
A
A
Department of Internal Medicine, University of Pisa, via Roma, 67, 56100, Pisa, Italy. a.antonelli@med.unipi.it
Ferri
C
C
Fallahi
P
P
Giuggioli
D
D
Nesti
C
C
Longombardo
G
G
Fadda
P
P
Pampana
A
A
Maccheroni
M
M
Ferrannini
E
E
D000368:Aged; D000704:Analysis of Variance; D044963:Biopsy, Fine-Needle / Q000379:methods; D016022:Case-Control Studies; D003449:Cryoglobulinemia / Q000097:blood / Q000821:virology*; D005260:Female; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000000981:diagnostic imaging; D015995:Prevalence; D013959:Thyroid Diseases / Q000000981:diagnostic imaging / Q000821:virology*; D014463:Ultrasonography