S3652 SOS: A Medication Crisis

Abstract

Introduction: Hepatic sinusoidal obstructive syndrome (SOS) is characterized by the absence of cirrhosis on liver biopsy, portal hypertension, and histological signs of portal sinusoidal vascular disease. It is a rare condition that often develops following hematopoietic stem cell transplantation (HSCT). We describe a case of SOS as a sequela of herbal supplement use. Case Description/Methods: A 65-year-old white woman was referred to the ED for progressive shortness of breath in the setting of new onset ascites. She had past medical history of Type 2 diabetes, hypothyroidism, and osteoarthritis. She denied the use of medication but reported taking multiple herbal supplements. She underwent paracentesis with SAAG of 1.6 and TP 2.6, which may be consistent with SOS. The liver biopsy showed porto-sinusoidal vascular disease. Small portal tracts were sclerotic with absence of normal veins. Some portal tracts contained inappropriate vascular spaces, with areas of diffuse sinusoidal dilatation. These findings were consistent with SOS and the patient was discharged with recommendation to discontinue all herbal supplements. She returned with severe liver failure and was referred to tertiary transplant center. Due to morbid obesity, she was not a candidate for liver transplant and transferred to hospice. Discussion: SOS is a rare and potentially fatal form of hepatic injury that occurs predominantly after HSCT. SOS is also observed in relation to herbal supplements containing pyrrolidine alkaloids (PAs), antineoplastic drugs, alcohol, contraceptives, and liver radiation. Mechanism of injury is believed to be toxin-induced damage to endothelial cells in the liver followed by cell necrosis and extrusion into sinusoids, leading to obstruction and congestion. Liver biopsy is the gold standard for diagnosis. Management focuses on prevention of further injury, support for complications, and liver transplantation in severe cases. The true incidence of herbal supplement induced SOS is unknown and likely underestimated. To the best of our knowledge, this is one of the very few cases describing herbal supplement use causing SOS leading to acute liver failure requiring transplantation.