Thyroid hormonal disturbances related to treatment of hepatitis C with interferon-alpha and ribavirin

A systematic review and meta-analysis of endocrine-related adverse events associated with interferon

OBJECTIVES

To perform a systematic review and meta-analysis of interferon and endocrine side effects, including their incidence, evaluation, and management.

METHODS

PubMed was searched through March 7th, 2021, by 2 authors independently (LH Wang and H Zhao). Early phase I/II, phase III experimental trials, prospective and retrospective observational studies were included. Stata 16.0 (StataCorp LLC, 16.0) was the main statistical software for meta-analysis. The weighted incidence and risk ratio were estimated for primary thyroid disease and diabetes mellitus.

RESULTS

A total of 108 studies involving 46265 patients were included. Hypothyroidism was the most common thyroid disorder, followed by hyperthyroidism. IFN α+RBV treated patients experienced hypothyroidism in 7.8% (95%CI, 5.9-9.9), which was higher than IFN α (5.2%; 95%CI, 3.7-6.8) and IFN β (7.0%; 95%CI, 0.06-23.92). IFN α+RBV treated patients experienced hyperthyroidism in 5.0% (95%CI, 3.6-6.5), which was higher than IFN α (3.5%; 95%CI, 2.5-4.8) and IFN β (3.4%; 95%CI, 0.9-7.5). The summary estimated incidence of painless thyroiditis was 5.8% (95%CI, 2.8-9.8) for IFN α, and 3.5% (95%CI,1.9-5.5) for IFN α+RBV. The summary estimated incidence of diabetes was 1.4% (95%CI, 0.3-3.1) for IFN, 0.55% (95%CI, 0.05-1.57) for IFN α, 3.3% (95%CI,1.1-6.6) for IFN α+RBV.

CONCLUSIONS

Our meta-analysis shows a high incidence of endocrine adverse events provoked by IFN, further reinforced by combined RBV treatment.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022334131.

Thyroid Dysfunction in Chronic Hepatitis C Patients Treated with the Combined Pegylated Interferon-Ribavirin Therapy

Hepatitis C virus (HCV) is an Egyptian serious national health problem. The combination of pegylated interferon (PEG-IFN) with ribavirin (RIB) was considered the established therapy for chronic hepatitis C (CHC), and it was associated with several adverse effects, including thyroid dysfunction (TD). The aim of this work was to study TD in CHC patients receiving PEG-IFN+ RIB therapy. This retrospective study included 100 adult patients attending the outpatient clinics at AL-Kahera Al-Fatemya hospital and were eligible candidates for PEG-IFN+ RIB therapy. Thyroid hormonal profile (thyroid-stimulating hormone, free triiodothyronine, and free thyroxine) was done before initiation of treatment (week 0) and at weeks 12, 24, 48, and 72. The incidence of TD was more evident by the end of treatment (week 48); it was found to be 35%, mostly in the form of hypothyroidism, while the least incidence was detected by week 12 (2%), all in the form of hyperthyroidism. Generally, hypothyroidism was higher than hyperthyroidism in multiple folds. Thyroid profile was not significantly related to viral load.

Inflammation and increased myxovirus resistance protein A expression in thyroid tissue in the early stages of Hashimoto's thyroiditis

BACKGROUND

The role of viruses as environmental triggers for Hashimoto's thyroiditis (HT) is controversial. Thyroid epithelial cells express a variety of molecules involved in antiviral responses. This study combined histological, immunological, and virological tests to describe changes in tissue from patients with newly diagnosed and untreated HT. To study the early events, patients with positive thyroid peroxidase antibodies (TPO-Ab) and normal thyroid function were also included. This stage was defined as "prethyroiditis."

METHODS

Thyroid tissue was collected from 47 patients with high titers of TPO-Ab and from 24 controls. Seventeen patients had prethyroiditis, 17 had subclinical hypothyroidism, and 13 had overt hypothyroidism. The interferon (IFN)-α/β-inducible myxovirus resistance protein 1 (myxovirus resistance protein A; MxA) was used as a surrogate marker for type I IFN expression. Inflammation, expression of MxA, and the presence of the enteroviralcapsid protein (VP1) were characterized by immunohistochemistry. The presence of enterovirus (EV) RNA was examined by in situ hybridization.

RESULTS

The density of CD4+ T cells was increased in all three patient groups, while CD8+ T cells were increased only in patients with overt hypothyroidism. The density of plasma cells increased as the disease progressed. The density of plasmacytoid dendritic cells and the expression of MxA were significantly increased in all patient groups compared with controls (p<0.01). EV RNA was present in 11% of HT patients, but in none of the control subjects, whereas the enteroviral protein was detected in 19% and 16%, respectively.

CONCLUSION

The inflammatory reaction in the thyroid gland is a very early event in the pathogenesis of HT. The increased expression of MxA in the inflamed tissue suggests that type I IFN plays a role in disease development. Whether this is virus-dependent needs to be explored in further studies.

Thyroid disturbance related to chronic hepatitis C infection: role of CXCL10

Association between autoimmune thyroid diseases (AITD) and hepatitis C is controversial, but may occur or worsen during alpha-interferon treatment. The mechanism responsible for autoimmune diseases in infected patients has not been fully elucidated. This study aims to evaluate the frequency of AITD in chronic hepatitis C and the association of chemokine (CXC motif) ligand 10 (CXCL10) and AITD. One hundred and three patients with chronic hepatitis C and 96 controls were prospectively selected to clinical, hormonal, thyroid autoimmunity and ultrasound exams, besides thyroxine-binding globulin (TBG) and CXCL10 measurements and hepatic biopsies. The frequency of AITD among infected subjects was similar to controls. TT3 and TT4 distributions were right shifted, as was TBG, which correlated to both of them. Thyroid heterogeneity and hypoechogenicity were associated with AITD. Increased vascularization was more prevalent in chronic hepatitis C.CXCL10 was higher in infected patients (p=0.007) but was not related to thyroid dysfunction. Increase in CXCL10 levels were consistent with hepatic necroinflammatory activity (p=0.011). In summary, no association was found between chronic hepatitis C and AITD. Infected subjects had higher TT3 and TT4 which were correlated to TBG. Increased CXCL10 was not associated to thyroid dysfunction in HCV-infected population.