ANNALS OF IBADAN POSTGRADUATE MEDICINE
A. C. Jemilohun1 and O. G. Adewoye2
Autoimmune hepatitis (AIH) is a rare cause of chronic liver disease (CLD). It presents with varied clinical features from acute hepatitis to CLDs like chronic viral hepatitis and alcoholic liver disease, making it difficult to diagnose in the absence of a high index of suspicion and adequate laboratory support. Autoantibody-mediated hepatocyte injury is the major feature of AIH.
We present a 44 year old woman with recurrent jaundice, ascites, splenomegaly, coagulopathy, negative chronic viral hepatitis screening, elevated IgG and positive anti-smooth muscle antibody. The patient responded well to immunosuppressive therapy. This report brings to the fore the need for physicians to maintain a high index of suspicion and thoroughly evaluate all CLD cases of seemingly ‘unknown’ etiology for AIH in order to prevent progression to end-stage liver-disease, since the disease is highly amenable to immunosuppressive therapy.
Keywords: Autoimmune hepatitis, Autoimmune liver disease, Chronic liver disease, Nigeria
Dr. A.C. Jemilohun
Department of Medicine,
LAUTECH Teaching Hospital,
Ogbomoso, Oyo State,
Autoimmune hepatitis (AIH) is a non-contagious chronic inflammatory disease that results from autoantibody-mediated hepatocyte injury. Autoimmune hepatitis, primary biliary cirrhosis and primary sclerosing cholangitis are together classified as autoimmune liver disease.1
AIH is classified into different types on the basis of the serum autoantibody profiles. The common denominator for all the types is the presence of hypergammaglobulinemia, precisely IgG.2 Type 1 AIH is defined by the presence of antinuclear antibody (ANA), anti-smooth muscle antibody (Anti-SMA), or both and constitutes 80% of AIH cases.2 It is also commonly associated with other autoimmune diseases like autoimmune thyroiditis, celiac disease and ulcerative colitis, with about 25% having cirrhosis at presentation.2
Type 2 AIH is characterized by the presence of antiliver kidney microsomal (Anti-LKM) 1 and/or anti-LKM 3 and/or anti-liver cytosol1 (Anti-LC1) antibodies.2 It is commoner in children, acute severe presentation does occur, and progression to cirrhosis commonly follows.2
The diagnosis of AIH is usually suspected when ongoing hepatocellular inflammation cannot be explained on the basis of chronic viral infection, alcohol consumption, or exposure to hepatotoxic medications or chemicals.2 As such, it is often a diagnosis of exclusion.
The incidence, prevalence and characteristics of AIH vary in different geographical regions. On a general note, it has a mean incidence of 1-2 per 100,000 and a point prevalence of 11–17 per 100,000.2 It is commoner in women (especially young women) than men with a ratio around 4:1 but it occurs in all age groups, races and geographical areas.2–5 The exact prevalence of the disease is not known in Nigeria as most studies on CLD focused on viral hepatitis, alcoholic liver disease and hepatocellular carcinoma. Only one case report of AIH in Nigeria was found in our literature search.6 A case of a 9-year-old girl with co-occurring wild-type chronic hepatitis B and antinuclear antibody-positive autoimmune hepatitis was reported in Senegal, a West African country.7 We present a young woman with liver cirrhosis that resulted from autoimmune hepatitis. The rarity of the disease, as well as the scarcity of reported cases in Nigeria, necessitated this effort.