Infective endocarditis is a potential differential diagnosis of systemic lupus erythematosus: case report

Abstract

Background: Systemic Lupus Erythematosus (SLE) is multisystemic autoimmune chronic inflammatory disease. It has a relapsing remitting course. Here, we present a male patient with SLE who presented with signs and symptoms mimicking sub-acute infective endocarditis.

Case report: A 28 year old male presented with fatigue, fever, arthritis, and anaemia. He had past history of oral ulcers. Antinuclear antibody ANA was positive. Diagnosis of SLE depending on 2012 SLICC SLE criteria1 was done and methylprednisolone IV pulse therapy was given for 3 days. On the 4th day he developed chest pain for which echocardiography was done and showed vegetation. Because of suspicion of infective endocarditis IE which cannot be excluded at that time, IV antibiotics were started. Blood culture was negative, it can be negative in 2% to 40% of IE patients, so antibiotics were continued for 4 weeks. Echocardiography repeated at the end of 4th week revealed no vegetation. The patient was discharged and was asked to come back for follow up and to repeat ANA and anti-dsDNA antibodies. At the 5th week, the patient came with active arthritis, fatigue, discoid rash and vasculitic body rash. ANA was repeated and found to be highly positive 1:10240. A final diagnosis was SLE associated with Libman Sacks endocarditis.

Conclusion: Infective endocarditis shared a lot of signs and symptoms of SLE. Antinuclear antibodies are also positive in infective endocarditis and this makes some diagnostic difficulties.

Key words: Systemic lupus erythematosus, Libman Sacks endocarditis, Infective endocarditis