Lesson of the month 2: When steroids stop working - infective endocarditis, the great mimicker

Abstract

A 63-year-old man with an extensive travel history to South East Asia presented with generalised malaise, temporal headaches and high inflammatory markers. He was treated with corticosteroids for presumed giant cell arteritis. Unsuccessful attempts to wean him from prednisolone prompted further investigations by rheumatology, haematology and finally ophthalmology. Roth spots were identified which prompted blood cultures to be taken. All three sets grew Streptococcus sinensis, an alpha-haemolytic Streptococcus reported as an emerging cause of endocarditis worldwide. The patient had signs of severe aortic regurgitation, confirmed on transthoracic echo. A transoesophageal echo demonstrated large aortic valve vegetations. He underwent an aortic valve replacement and completed 6 weeks of intravenous antibiotics with resolution of his symptoms.This case illustrates the importance of challenging a previous diagnosis, including repeat examination, when a patient's condition does not evolve as expected. Endocarditis is recognised as a great imitator and the diagnosis remains challenging.

Keywords: Chronic infective endocarditis; Streptococcus sinensis; emerging infections.

Fig 1.

Positron emission tomography–computed tomography showing increased bone marrow uptake, hepato-splenomegaly and no evidence of systemic vasculitis.

Fig 2.

Fundoscopy showing Roth spots.

Fig 3.

Patient’s timeline and C-reactive protein values (mg/L).

Fig 4.

Transoesophageal echo demonstrating large vegetations on the aortic valve.