Case Report: A Rare Syncope Case Caused by Abernethy II and a Review of the Literature

Liver bypass in the development of pathogen-associated pulmonary vascular disease: contribution of mesocaval and portosystemic shunts

Portosystemic and mesocaval shunts are aberrant vascular connections that bypass hepatic detoxification process, directly linking the portal to the systemic circulation. These shunts, whether congenital or acquired, might play a pivotal role in the pathogenesis of systemic inflammatory diseases, such as schistosomiasis-associated pulmonary hypertension (Sch-PH) by facilitating the dissemination of pathogen-derived eggs and antigens from the gut and mesentery into the lungs. Beyond the translocation of Schistosoma mansoni eggs, emerging evidence implicates that gut-lung microbiome dysbiosis contributes to the development of pulmonary hypertension (PH) in the preclinical animal model of Sch-PH. Sch-PH emerges as a chronic complication of schistosomiasis and evolves silently, progressively increasing the mean pulmonary arterial pressure and vascular resistance, leading to right heart hypertrophy, failure, and significant morbidity and mortality. Chronic schistosomiasis is often linked to the development of portal hypertension, which significantly contributes to the formation of the porto/mesocaval shunt as a compensatory response that can have far-reaching implications on pulmonary vascular physiology. In addition, portal hypertension compromises the integrity of the intestinal barrier, exacerbating peritoneal and mesenteric inflammation, potentially facilitating microbial and metabolite entrance into the systemic circulation. This article briefly discusses the mechanisms by which porto/mesocaval shunts contribute to PH, especially Group I PH, focusing on the interplay between portosystemic shunting, microbial translocation, and systemic dissemination of proinflammatory metabolites.

Case Report: Type Ib Abernethy malformation

Congenital extrahepatic portosystemic shunt, also known as Abernethy malformation, is a rare anatomic vascular malformation. Patients with Abernethy malformation may present with abdominal pain, abnormal liver function tests, hepatopulmonary syndrome, pulmonary hypertension, and/or portosystemic encephalopathy. Accurate identification of the shunt and portal vein and effective management of complications is vital in these patients. Routine imaging examinations are useful for the diagnosis and classification of Abernethy malformation. However, these examinations may miss some portal vein branches. Digital subtraction angiography is invaluable when routine imaging cannot precisely identify the hepatic portal vein in this situation.

Rare portal hypertension caused by Abernethy malformation (Type IIC): A case report

BACKGROUND

Abernethy malformation is a rare congenital vascular malformation with a portosystemic shunt that may clinically manifest as cholestasis, dyspnea, or hepatic encephalopathy, among other conditions. Early diagnosis and classification are very important to further guide treatment. Typically, patients with congenital portosystemic shunts have no characteristics of portal hypertension. Herein, we report an 18-year-old female with prominent portal hypertension that manifested mainly as rupture and bleeding of esophageal varices. Imaging showed a thin main portal vein, no portal vein branches in the liver, and bleeding of the esophageal and gastric varices caused by the collateral circulation upwards from the proximal main portal vein. Patients with Abernethy malformation type I are usually treated with liver transplantation, and patients with type II are treated with shunt occlusion, surgery, or transcatheter coiling. Our patient was treated with endoscopic surgery combined with drug therapy and had no portal hypertension and good hepatic function for 24 mo of follow-up.

CASE SUMMARY

This case report describes our experience in the diagnosis and treatment of an 18-year-old female with Abernethy malformation type IIC and portal hypertension. This condition was initially diagnosed as cirrhosis combined with portal hypertension. The patient was ultimately diagnosed using liver histology and subsequent imaging, and the treatment was highly effective. To publish this case report, written informed consent was obtained from the patient, including the attached imaging data.

CONCLUSION

Abernethy malformation type IIC may develop portal hypertension, and traditional nonselective beta-blockers combined with endoscopic treatment can achieve high efficacy.