2614 Astrovirus Enteritis in an Immunocompetent Adult in the Setting of Chronic Proliferative Synovitis

Abstract

INTRODUCTION: Astrovirus enteritis is a clinical entity seen mainly in children and immunocompromised adults resulting in severe diarrheal episodes. It is quite rarely implicated in acute gastroenteritis in immunocompetent adults with only few cases reporting its incidence. Here, we report a case of Astrovirus enteritis in an immunocompetent adult with chronic proliferative synovitis and positive ANA titers. CASE DESCRIPTION/METHODS: We present a 38-year-old woman with history of chronic proliferative synovitis who presented with acute nausea, crampy mid abdominal pain, and profuse non-bloody diarrhea after 12 hours of eating from a restaurant. The diarrheal episodes were associated with fevers up to 103oF with chills and rigors. The patient reported to have two recent sick contacts with similar diarrheal episodes and a course of amoxicillin 1 month ago for a dental indication. However, she denied any vomiting, recent meat, dairy or egg consumption or travel history. She had no past medical history of gastrointestinal complaints, immunosuppression or any new medications. Clinical examination only revealed mild abdominal diffuse tenderness. Initial clinical workup was remarkable for a mild leukocytosis, newly increasing AST and ALT, but normal total bilirubin, ALP and lipase levels. Microbiological investigation revealed positive Astrovirus in GI PCR, negative C. difficile assay and negative HIV status. An autoimmune workup revealed positive ANA titers of 1:80 in the setting chronic proliferative synovitis. The patient underwent supportive treatment for her diarrhea with Loperamide and IV fluids following which she improved clinically. DISCUSSION: Astrovirus is a positive single stranded RNA virus implicated in acute gastroenteritis in children and immunocompromised individuals. However, it has a low prevalence among healthy adults which is hypothesized to be due to acquired immunity gained from a prior childhood infection. In this patient, her chronic proliferative synovitis with raised ANA titers seems to have increased her predisposition to acquiring Astrovirus enteritis. Patients with chronic inflammatory conditions like SLE or synovitis seem to be more prone to viral infections due to their pro-inflammatory condition, making them more susceptible to infections that are otherwise cleared by the adult immune system. Hence, it is important to consider this clinical entity when assessing severe gastroenteritis in patients with pro-inflammatory status.