Serum immunoglobulin A levels and alcohol-induced liver disease

Recent data suggest intestinal immunity including immunoglobulin A (IgA) may contribute to the pathogenesis of alcohol-induced liver disease (ALD).

We documented serum IgA levels in ALD patients and determined whether those with elevated levels of IgA (E-IgA) had similar, more, or less advanced disease and different rates of progression than those with normal levels of IgA (N-IgA). Standard liver function tests (bilirubin, international normalized ratio [INR], and albumin), model for end-stage liver disease (MELD), and Fibrosis-4 (FIB-4) scores were used as indicators of disease severity.

From the study centre's clinical database, we identified 175 adult patients with ALD, 107 (61%) with E-IgA and 68 (39%) with N-IgA. Gender distribution and mean age of the two cohorts were similar. E-IgA patients had biochemical evidence of more advanced liver disease (higher serum bilirubin and INR and lower albumin levels) than N-IgA patients (ps < .05). E-IgA patients also had significantly higher median MELD and FIB-4 scores (ps < .01). A higher percentage of E-IgA patients had FIB-4 values in keeping with advanced fibrosis or cirrhosis (55% versus 28%, p = .02). After mean follow-up periods of approximately 4 years, liver biochemistry and MELD and FIB-4 scores changed to similar extents in the two cohorts.

Serum IgA levels were increased in approximately 70% of ALD patients. Although these patients had biochemical and non-invasive indicators of more advanced disease, elevations in serum IgA levels do not predict disease progression; therefore, IgA is unlikely to be of importance in the pathogenesis of ALD.