Abstract
Dengue hepatitis is mostly asymptomatic but can lead to liver failure. Autoimmune hepatitis is mainly the disease of females and a potentially treatable cause of chronic liver disease. We report a rare case in which autoimmune hepatitis was unmasked by Dengue infection. The patient was managed for AIH with steroids and azathioprine and became asymptomatic in 30 days. Dengue is a proven risk factor for many autoimmune conditions but its association with AIH is not studied.
Introduction
Dengue is the most common arboviral infection in the world. Almost 2.5 billion people in 100 endemic countries are susceptible to this mosquito borne illness.1,2 Multiple organ systems are affected by dengue but the most common is hepatic system. Dengue hepatitis is asymptomatic in the majority of patients but can lead to a spectrum from symptomatic liver derangement to acute liver failure. Autoimmune hepatitis is, by contrast mainly a disease of females 3 and a potentially treatable cause of chronic liver disease. We report a rare case in which the latter was unmasked by the former.
Case report
A 40 year old man presented in our emergency department with a fever with chills, icterus, abdominal pain and distention for five days. The fever was associated with holocranial headache and myalgia without any rash, burning micturition or joint pains. He also complained of three episodes of vomiting the previous day which were not bilious nor blood-stained. He denied any comorbidity such as diabetes, hypertension previous blood transfusions or alcohol consumption. He had a similar episode 12 years previously when he was diagnosed to have dengue fever but had recovered without any complications. On general physical examination, he was conscious, oriented, febrile to touch (38.3°C) with a body mass index of 22.7 kg/m2. He was jaundiced with a tachycardia (100 beats/minute) and hypotensive (112/66 mm Hg).
He had right hypochondrial tenderness with ascites, without other signs. Initial laboratory investigations revealed thrombocytopenia (platelet count – 15 x 109/L), conjugated hyperbilirubinemia (Total Bilirubin – 0.3438 mmol/L, Direct Bilirubin – 0.1881 mmol/L), transaminitis (AST- 47.09 ukat/L, ALT -20.82 ukat/L & ALP- 3.33 ukat/L) and hypoalbuminemia (0.4063 mmol/L). Abdominal ultrasonography showed altered hepatic echotexture, moderate ascites and an oedematous gallbladder. Infectious disease serology showed Dengue IgM positivity while tests for other tropical infections and viral hepatitis were negative.
Our patient's condition improved and he became afebrile after three days. Despite symptomatic improvement conjugated hyperbilirubinemia with raised transaminase levels persisted beyond seven days.
Further investigations revealed Antinuclear antibody positivity (1:160, Homogenous pattern) but Anti LKM-1 and an extended nuclear antibody panel was negative. Further workup revealed Anti smooth muscle antibody positivity (1:80) with elevated IgG levels (1917 mg/dl) and a liver stiffness on a fibro scan of 16 kpa. He had normal serum ceruloplasmin and iron levels with absence of Kayser-Fleischer rings on slit lamp ocular examination. A liver biopsy revealed a lymphoplasmacytic infiltrate with focal ballooning and rosette formation. These findings were compatible with autoimmune hepatitis, scoring seven points and was diagnosed Type 1.
We commenced our patient on prednisone and azathioprine and gradually his bilirubin and liver enzyme levels decreased, becoming normal within three months. He continues on low dose prednisone and azathioprine and remains asymptomatic without any episodes of disease flare.
Discussion
Dengue infection is being increasingly recognized as a cause of acute on chronic liver disease in India. A cholestatic pattern is rare4 in dengue and other courses should be evaluated. In our case we believe there was an unmasking of autoimmune hepatitis by dengue. This has been associated with many autoimmune conditions such as Reiter syndrome, myasthenia gravis, autoimmune encephalomyelitis, multiple sclerosis and systemic lupus erythematosus (SLE)5,6
In the USA, autoimmune hepatitis affects 100,000 to 200,000 persons, and it accounts for 2 to 3% of paediatric and 4 to 6% of adult liver transplants performed in Europe and the USA.7 Almost 25% of adult autoimmune hepatitis patients are clinically asymptomatic. The most common finding is hepatomegaly. Cirrhosis is present in 28 - 33% at presentation, which suggests that it is underdiagnosed in older adults 8
In our case, an episode of dengue fever had occurred 12 years before and during the second episode he developed liver function derangement. A recent nationwide population-based study demonstrated dengue as a risk factor for the development of SLE. This association was significant when the duration between dengue and the diagnosis of autoimmune disease was less than three months. 9 To our knowledge this is the first case in which autoimmune hepatitis was unmasked or may have been triggered by dengue infection. This hypothesis needs further investigation and research.
Footnotes
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article
