HCV Infection Linked to Risk for Chronic Inflammatory Skin Diseases

Cryoglobulins are immunoglobulin (Ig) complexes that precipitate from the serum at low blood temperatures (<37°C) and then redissolve during incubation.1 Cryoglobulinemia occurs when excess cryoglobulins circulate in serum, resulting in different clinical manifestations based on the immunologic composition of the cryoglobulins. Three immunochemical types of cryoglobulins have been described. Of these, type 2, or MC, is most commonly found in patients with chronic HCV infection, with HCV infection accounting for 95% of all MC cases.1,2 Patients with MC have a mixture of circulating monoclonal IgMs and polyclonal IgGs, with the IgMs having rheumatoid factor (RF) positivity. Rarely, patients with chronic HCV infection may have immunochemical type 3, in which both IgM and IgG are polyclonal. Patients with type 2 or 3 cryoglobulinemia should be screened for HCV infection, and those with HCV and worsening renal function or cutaneous involvement should be tested for cryoglobulinemia.3 Photo Credit: ISM/Pr JL KEMENY.

Cryoglobulins are immunoglobulin (Ig) complexes that precipitate from the serum at low blood temperatures (<37°C) and then redissolve during incubation.1 Cryoglobulinemia occurs when excess cryoglobulins circulate in serum, resulting in different clinical manifestations based on the immunologic composition of the cryoglobulins. Three immunochemical types of cryoglobulins have been described. Of these, type 2, or MC, is most commonly found in patients with chronic HCV infection, with HCV infection accounting for 95% of all MC cases.1,2

Patients with MC have a mixture of circulating monoclonal IgMs and polyclonal IgGs, with the IgMs having rheumatoid factor (RF) positivity. Rarely, patients with chronic HCV infection may have immunochemical type 3, in which both IgM and IgG are polyclonal. Patients with type 2 or 3 cryoglobulinemia should be screened for HCV infection, and those with HCV and worsening renal function or cutaneous involvement should be tested for cryoglobulinemia.3

Photo Credit: ISM/Pr JL KEMENY.

The association between hepatitis C virus infection and chronic inflammatory skin diseases is assessed.

Hepatitis C virus (HCV) infection is associated with an increased risk for chronic inflammatory skin diseases (CISDs), but treatment with interferon-based antiviral therapy (IFN-based AVT) may be associated with a decrease in this risk, according to study findings published in the Journal of Dermatology.

The study included 23,509 participants (median age, 55.7 years; 49.1% men) with HCV infection from the Taiwan National Health Insurance (NHI) Research Database. Participants identified and included in this study were recorded in the NHI database from 1998 to 2011. In addition to analyzing HCV infection, the researchers also investigated use of IFN-based AVT with pegylated IFN-α-2b and ribavirin. A total of 94,036 age- and sex-matched control participants without HCV infection were also included in the analysis. The occurrence of CISD comprised the primary outcome.

Approximately 18.5% of patients with HCV infection received IFN-based AVT. A total of 300 patients with HCV developed CISD (incidence rate, 153.43 cases per 100,000 person-years), while 213 participants without HCV infection developed CISD (overall rate, 27.01 cases per 100,000 person-years). In an analysis adjusted for potential confounders, the researchers found that those with HCV infection had a 6.34-fold (95% CI, 5.30–7.58) increased risk of CISD compared with control participants.

In HCV-infected patients, the median duration between the index date and the initial CISD diagnosis was 3.4 years, and the median duration between these same time periods for control participants was 7.2 years (P <.0001). According to multivariable regression analyses, treatment with IFN-based AVT was associated with a decreased risk for CISD (adjusted hazard ratio [aHR], 0.42; 95% CI, 0.28–0.64; P <.0001).

In terms of individual CISD, patients with HCV infection had an increased risk for psoriasis (aHR, 6.42; 95% CI, 4.94–8.32; P <.0001), lichen planus (aHR, 13.14; 95% CI, 7.10–24.31; P <.0001), vitiligo (aHR, 6.45; 95% CI, 3.74–11.10; P <.0001), alopecia areata (aHR, 6.69; 95% CI, 4.28–10.44; P <.0001), and cutaneous lupus erythematosus (aHR, 13.48; 95% CI, 4.85–37.43; P <.0001).

The researchers note that only patients who sought medical attention were included in the study, which may have led to underestimation of CISD incidence in this population.

In their conclusion, the investigators wrote that their findings suggest “active monitoring of CISD in patients with HCV infection” may be warranted.

Disclosure: Multiple authors declared affiliations with the pharmaceutical industry. Please refer to the original article for a full list of disclosures.

Reference

Ma SH, Tai YH, Dai YX, Chang YT, Chen TJ, Chen MH. Association between hepatitis C virus infection and subsequent chronic inflammatory skin disease. J Dermatol. Published online August 30, 2021. doi:10.1111/1346-8138.16129