Due to the endemicity of acute viral hepatitis caused by hepatitis A and hepatitis E most clinicians do not investigate a typical “viral hepatitis” case. In the present case the jaundice can be explained only by the viral hepatitis alone. But persistence of jaundice led us to investigate the present case. Thus, the possibility of missing a diagnosis in resource poor setting is high where both the diagnostic facilities and follow up of patients is often inadequate. However, one more basic indicator pointing towards a chronic disease were the anthropometric measurements. The importance of diagnostic imaging and follow-up of disease course is illustrated in this case. We now discuss various possible clinical presentations and associated congenital anomalies of the Abernethy malformations followed by diagnostic workup and treatment options.
Congenital intra-hepatic portosystemic shunts can present in the early neonatal period with growth restriction [7
], galactosemia [8
], neonatal cholestasis [11
], and hepatic encephalopathy [12
]. Cases of CEPSh have a variable presentation. In countries having neonatal screening programmes, some cases can be diagnosed by neonatal screening tests due to presence of galactosemia [8
]. Many patients are diagnosed due to associated defects like heart disease, which are present in up-to 60% of the patients [4
]. Symptoms of secondary complications like hypoglycemia, hyperammonemia, encephalopathy and cardiac failure can be transient and can resolve spontaneously [12
]. Subclinical course is more common and some patients might not have any symptoms throughout life [12
]. Later, other lesions like nodular regenerative hyperplasia, partial nodular transformation, hepatoblastoma, hepatocellular carcinoma and adenoma can develop [4
The two possible explanations of development of these neoplasm are: a) diversion of hepatotrophic substances like insulin and glucagon away from liver leading to altered development, function and regenerative capacity of the liver and b) increased arterial hepatic flow [4
]. Our patient does not have any evidence of hepatic neoplasm (normal alfa feto protein) at present after more than two year follow up, however in view of the documented increased risk of hepatocellular carcinoma and adenoma we have advised a regular radiological and serological surveillance at six monthly interval.
Despite presence of porto-systemic shunt, patients with CEPSh usually do not present with encephalopathy. Hyperammonemia may be present without encephalopathy especially at younger age. Clinical encephalopathy is more common at older age. The possible explanations are a) an increased sensitivity of the aging brain to toxic effects of ammonia and other toxic metabolites b) extent of shunt determined by the portal/systemic shunt ratio. A shunt ratio of more than 60% may predict the age of onset of hepatic encephalopathy [6
]. In our case, the ammonia concentration was within normal range and patient has had no clinical evidence of encephalopathy till date.
Varying degree of dyspnoea on exertion could be a presentation of portopulmonary hypertension or hepatopulmonary syndrome. Hepatopulmonary syndrome presents with hypoxemia and or orthopnea with clubbing; due to abnormal intrapulmonary vascular dilatations [13
]. In our patient there is no evidence of hepatopulmonary syndrome, till date clinically as well as on echocardiography.
Congenital hepatic shunt can also present with hypoglycaemia. This might be due to combined effect of defective uptake of glucose and hyperinsulinemia due to reduced hepatic degradation of normal quantity of secreted insulin [18
]. A work up of common associated anomalies was done but revealed no anomaly. These include cardiac defects (60%), biliary atresia (20%), polysplenia (20%), situs inversus (10%) and malrotation (10%) [14
A diagnosis of Abernethy malformation is made by non-invasive cross-sectional imaging techniques such as ultrasound, CT or MRI, which show the shunt and any intrahepatic portal vein branches [17
The planning of treatment is dependent on the type of shunt as classified by Morgan and Superina [3
] and needs to be tailored to the individual patient in accordance with preoperative evaluation [15
]. Usually in patients with CEPSh type I, occlusion of shunt is not performed, as it is the only drainage route for the mesenteric venous blood. But recently published experience by several authors [15
] point that many patients with CEPSh type I malformations might have small portal vein radicals which cannot be seen on ultrasonography but could be visualized on shunt angiography. The balloon occlusion test of the fistula can also be done [15
]. This test helps to decide on a single stage or a two-staged shunt closure procedure. A two-step procedure allows the portal branches to enlarge slowly and can avoid acute severe portal hypertension [15
]. Extremely hypoplastic or undetectable portal veins will require banding of the fistula before closure [17
]. Shunt closure results in restoration of intrahepatic portal flow in most patients [17
]. Clinical improvement in form of regression of benign liver masses, and regression or stabilization of pulmonary, cardiac, neurological, and renal complications is seen in patients post shunt [17
]. CEPSh typeI patients also need clinical, biochemical and imaging follow-up [17
]; as is done in our patient. For patients with CEPSh type I developing complications like encephalopathy or neoplasms, till recently liver transplant was the only treatment option [6
], but transplant should be reserved for exceptionally complex anatomy where closure of the shunt is not possible.
Patients with CEPSh type II with hepatic encephalopathy can benefit by early shunt occlusion surgery [15
]. Reconstruction of the portal vein should be done early to avoid mesenteric venous congestion [20
]. Shunt surgery when possible is the treatment of choice for CEPSh type I and type II. Our patient is asymptomatic at present but since the patient has nodular lesion in the liver she should be considered “symptomatic”. In view of this our patient has been counselled for need for shunt surgery.