Case Presentation: A previously healthy 39-year-old male with a bicuspid aortic valve and mitral valve prolapse presented with three months of intermittent bilateral retro-orbital headache, abdominal discomfort, subjective fevers, night sweats, and 10-kg weight loss.
Two weeks prior to admission, he developed acute left-sided vision loss and left-sided weakness, and was diagnosed with right parietal brain hematoma. He underwent clot evacuation and decompressive hemicraniectomy.
Evaluation during that initial visit included brain MRI revealing a necrotic left occipital brain lesion; abdominal CT showing splenic artery aneurysm and left renal infarct; and transthoracic echocardiogram (TTE) showing the bicuspid aortic valve. His blood cultures were negative and he was discharged one week post-operatively.
The patient returned with persistent fevers, sweats, and abdominal pain, and blood cultures then grew Streptococcus sanguinis. Examination revealed Osler’s node on the right palm and a III/VI diastolic murmur at the aortic listening area. A repeat TTE was negative for vegetations; however, transesophageal echocardiogram showed a 1.3 cm aortic valve vegetation. CT of the abdomen showed rapid enlargement of the splenic artery aneurysm, requiring urgent coil embolization.
Discussion: This case of infective endocarditis (IE) included rare and highly morbid complications: intracranial hemorrhage (ICH) and mycotic aneurysm (MA). ICH may be due to arteritis or MA. Intracranial mycotic aneurysms (ICMAs) occur more frequently than other sites of MA. In one-third of cases with ICMA, concurrent extracerebral MA co-exists, as with our patient. Splanchnic MAs occur in less than 1% of IE cases and can occur in the superior mesenteric artery, renal artery, hepatic vasculature, or splenic artery. While a few dozen cases of splenic artery mycotic aneurysm (SAMA) secondary to IE have been reported, we report only the fourth case of a SAMA due to a Streptococcus viridans species IE and only the second case of SAMA and ICMA occurring in the same patient.
Conclusions: While endocarditis is known to cause MAs, suspecting endocarditis in the setting of aneurysm and other disparate clinical findings can be challenging. Our case of ICH and splenic artery aneurysm of unknown etiology was an elusive, but tell-tale sign of complicated surreptitious IE.
