title: Thyroid involvement in patients with overt HCV-related mixed cryoglobulinaemia.
abstract: 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.
authors.affiliation: Department of Internal Medicine, University of Pisa, via Roma, 67, 56100, Pisa, Italy. a.antonelli@med.unipi.it
authors.forename: A
authors.initials: A
authors.lastname: Antonelli
authors.forename: C
authors.initials: C
authors.lastname: Ferri
authors.forename: P
authors.initials: P
authors.lastname: Fallahi
authors.forename: D
authors.initials: D
authors.lastname: Giuggioli
authors.forename: C
authors.initials: C
authors.lastname: Nesti
authors.forename: G
authors.initials: G
authors.lastname: Longombardo
authors.forename: P
authors.initials: P
authors.lastname: Fadda
authors.forename: A
authors.initials: A
authors.lastname: Pampana
authors.forename: M
authors.initials: M
authors.lastname: Maccheroni
authors.forename: E
authors.initials: E
authors.lastname: Ferrannini
mesh_terms: 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