Case Presentation: A 45-year-old-man with no prior medical history presented to the emergency department with a symmetric lower extremity rash and recurrent fevers. The rash started two weeks prior as discrete mildly pruritic red lesions on his ankles and spread to his arms, torso and back. He subsequently developed recurrent fevers up to 38.9°C on a daily basis. He did not recall any tick bites or sick contacts. He denied intravenous drug use or new sexual partners.
On exam he was febrile (39.1°C) and tachycardic (116 beats per minute). Cardiovascular examination was pertinent for significant bilateral pitting edema of both legs. Heart and lung sounds were unremarkable. No hepatomegaly or splenomegaly was identified and neurological exam was non-focal. A diffuse non-blanching purpuric rash was noted predominantly over both legs. Admission labs showed a leukocytosis 11.4×109/L (3.5-10.5×109L), lactate 2.7mmol/L (0.9-1.7mmol/L) and a normocytic anemia (hemoglobin 9.5g/dL [13.5-17.5g/dL], and erythrocyte sedimentation rate 79 mm/1h [0-22 mm/h1]. Blood cultures were positive for alpha-hemolytic streptococci. He was treated for sepsis likely secondary to lower limb cellulitis with intravenous vancomycin, cefepime and doxycycline. However he had persistent recurrent fever with progressive worsening of the rash.
Human immunodeficiency virus, hepatitis B and C serology were negative. Given persistent symptoms, a transthoracic echocardiogram was performed which showed a mobile echo density (measuring 8mm x 1.2mm) arising from the ventricular surface of the aortic valve. This was confirmed on transesophageal echocardiogram and the patient was switched to IV ceftriaxone for treatment of native-valve endocarditis. Skin biopsy of the rash was consistent with infectious vasculitis. The patient did not have any prior cardiac history, rheumatic fever, or recent dental work. The organism was subsequently identified as Group D alpha-hemolytic Streptococcus bovis. After discharge he underwent a screening colonoscopy to rule out colorectal pathology. No macroscopic lesions were identified on colonoscopy. After 6 weeks of IV ceftriaxone he had complete resolution of his symptoms.
Discussion: Streptococcus bovis is a gram positive, catalase negative cocci in chains that encompasses the non-enterococcus component of Group D Streptococcus (GDS). GDS is found as normal colonic flora in 15% of humans. GDS bacteremia is significant as it has a strong association with colorectal cancer (16-32%) and infective endocarditis (~28%). Patients with GDS bacteremia/endocarditis typically present with subacute fevers, weight loss, and fatigue. This case is unique in that the patient’s initial manifestation was a rash secondary to infectious vasculitis. Echocardiography should be obtained to rule out endocarditis in any patient with positive blood cultures for GDS. Treatment is based on culture sensitivities. Duration of treatment is 2 weeks for bacteremia and a minimum of 4 weeks for endocarditis. Colonoscopy should be performed to rule out colorectal carcinoma.
Conclusions: This case represents a unique presentation for Streptococcus bovis in that the initial manifestation was a diffuse non-blanching rash. In patients presenting with subacute fevers and lethargy it is important to keep GDS on the differential. Once diagnosed, it is imperative to obtain proper testing to rule out endocarditis and colorectal cancer.
