Systemic Mastocytosis Complicated by Non-cirrhotic Portal Hypertension and Variceal Bleeding

Abstract

Introduction: Systemic mastocytosis is characterized by mast cell hyperplasia with infiltration and accumulation in at least one extracutaneous organ. While the most common site of extracutaneous involvement is the bone marrow, hepatic involvement may result in hepatic fibrosis and pre-sinusoidal, non-cirrhotic portal hypertension. Case: An 82 year-old woman with a history of systemic mastocytosis, confirmed by bone marrow biopsy three years prior, on chronic prednisone presented with maroon-colored stool and bright red blood per rectum. She reported no previous episodes of gastrointestinal bleeding. On arrival, the patient was hemodynamically stable. Exam disclosed an elderly woman with anicteric sclera, benign abdominal exam with no organomegaly, and external hemorrhoids with gross maroon-colored stool on digital rectal exam. Initial laboratory data was notable for Hgb 6.8 mg/dL, albumin 2.9 g/dL, platelets 76, creatinine 0.4 mg/dL, INR 1.22, and unremarkable liver function tests aside from a chronically elevated alkaline phosphatase of 249 U/L. Endoscopy demonstrated three columns of large esophageal varices (EV) at 28 cm with extension to gastroesophageal junction and red wale sign, moderate portal hypertensive gastropathy in the gastric cardia, and no ulcerations [Figure]. Five bands were placed with obliteration of the EV, nadolol was started for secondary prophylaxis, and the patient had no further episodes of bleeding. Abdominal ultrasound demonstrated normal appearing liver with patent hepatic and portal veins. Alternative testing to evaluate the etiology of portal hypertension was unremarkable. No liver biopsy was performed as the patient was already on prednisone for treatment of mastocytosis and was high-risk for bleeding.Figure 1Discussion: While the exact mechanism is unknown, it is postulated that non-cirrhotic portal hypertension may develop as a result of infiltration of inflammatory mast cells within the portal vein and obstruction of the sinusoids, thus resulting in increased portal pressures and pre-sinusoidal obstruction. Given the involvement of mast cells, the addition of histamine and leukotriene receptor antagonists is an important addition to traditional management. Overall, no study has identified what percent of patients with systemic mastocytosis develop portal hypertension. Ultimately, this case reinforces the importance of and need for appropriate portal hypertensive screening in patients with systemic mastocytosis.