Introduction

Infective endocarditis (IE) is still a life-threatening disease with a high morbidity and mortality. To date, in Germany the incidence of an acute IE is about 11.6/100.000 residents with an intrahospital mortality of 17% [1,2]. Therefore, the early diagnosis of an IE with beginning of an appropriate anti-infective therapy is crucial. Due to the high variability at clinical presentation, diagnosis of IE is sometimes challenging. Patients can present with acute, subacute or chronic symptoms. They can show signs of an acute infection like sepsis and fever. But also, unspecific symptoms like subfebrile temperature, weight loss, night sweats or fatigue can be shown, which may mislead the initial diagnosis as they are accompanied by many chronic diseases of the rheumatological, neurological or immunological field [3]. Around 70-87% of the cases of IE are caused by pathogens belonging to staphylococcus (Stapylococcus aureus 30%) and streptococcus (Streptococcus viridans around 17%) group, followed by enterococci (around 10%), pathogens of the HACEK-group and fungi (around 2%) [4]. Abiotrophia defectiva (A. defectiva) is a very rare specimen belonging to the streptococcus group, which is described to cause IE with a high risk of embolic complications, treatment failure and mortality [4-6]. Repetitive blood testing especially blood culture testing is crucial for the diagnosis of IE based on the Duke criteria and represents the basis of an calculated anti-infective therapy. Imaging modalities like transthoracic echocardiography (TTE), trans-oesophageal echocardiography (TOE), computer tomography (CT), nuclear imaging (PET) and cardiac magnetic resonance imaging (CMR) are important for confirmation of IE, assessment of the severity of valve defect and prognosis. Based on the latest ESC Guidelines a ‘Endocarditis Team’ should be involved for the therapeutic management right up to indication and timing of cardiac surgery [3]. Jehovah’s Witnesses belong to a distinct Christian movement, separate from mainstream Christianity. Founded in the United States in 1872 by Charles Russell, they have over 8 million members worldwide, with 170.000 in Germany. Their religious beliefs prohibit them from accepting whole blood transfusions or its primary components. A review shows that cardiac surgery in Jehova´s Witness patients without blood transfusion is feasible and can yield results equivalent to those of other patients. Advances in blood conservation methods, including the use of pharmacological agents such as iron and erythropoietin (EPO), have contributed to achieve favourable surgical outcomes [7].

Case Presentation

A 50-year-old man, presented to his family doctor with a 6-month history of intermittent fever, night sweats, weight loss (approx. 14 kg in the previous 6 months), abdominal pain and poor appetite. He noticed shortness of breath but denied chest pain, palpitation or cough. Seven months prior to his presentation, he had a dental extraction. He denied intravenous drug use, smoking or heart diseases and consumed alcohol only rarely. The patient was referred to the gastroenterology clinic in our hospital for further investigation due to splenomegaly and suspected segmental splenic infarct. On admission the patient was afebrile, had a regular heart rate of 95 beats per minute and a blood pressure of 121/94 mmHg. The physical examination revealed a pansystolic murmur in the mitral area, splenomegaly and vision impairment on both sides. Laboratory investigation revealed a normal blood count (hemoglobin of 11.4 g/dL, WBC 9.6 10⁹/L, platelets 316 x 10⁹/L), with enhanced levels of CRP 55.7 mg/L, serum creatinine 1.21 mg/dL [8]. ECG showed sinus rhythm with no reciprocal changes. Contrast sonography and CT scan of the abdomen showed segmental splenic infarct, mild splenomegaly and liver hemangioma (Figure 1). The patient was presented to cardiology and department for consultation. TTE and 3D-TOE showed a severe eccentric mitral regurgitation (MR) due to multiple vegetation’s on the posterior mitral leaflet (PML) and the anterior mitral leaflet (AML) with a maximum expansion of 16 x 8mm leading to a PML prolapse (Figure 2-3). The left ventricular ejection fraction was normal without any other heart valve defects; especially no further vegetation’s were detected. Brain MRI showed a small area of white matter abnormality suggestive of embolism in the right middle cerebral artery branches. Clinical examination showed no petechiae or Janeway lesions. Multiple sets of blood cultures could detect A. defectiva, which was tested sensitive to ampicillin and gentamicin. Hence, the patient was commenced on intravenous gentamicin (3mg/kg/day i.v. in 1 dose) and ampicillin (12g/day i.v. in 4 doses) leading to gradual CRP decrease. The TOE control showed no obvious reduction of the vegetation on the MV with persistent severe eccentric MR. In the further course, the patient developed acute cardiac decompensation with severe dyspnea due to MR, and therefore, indication for urgent surgical treatment was given. However, the patient, adhering to Jehovah’s Witness beliefs, declined any blood transfusions or blood products. Consequently, we admitted the patient to our intensive care unit for intravenous diuretic therapy, continued the intravenous antibiotic treatment, and initiated intravenous iron substitution (1.000 mg Ferrinject) to address the iron deficiency anemia. Subsequently, recombinant EPO (600 I.E./kg KG per week for 2 weeks) was administered to manage the progressing anemia associated with chronic endocarditis and iron deficiency. With these measures, hemodynamic stability was achieved and hemoglobin level reached 12 g/dl to minimize the risk of bleeding during upcoming operation. After 6 weeks of intravenous antibiotic treatment, the patient was discharged from our hospital. He was referred to cardiac surgery and received biological MV replacement (Carpentier-Edwards-Perimount 33

mm). Microbiological investigation of the native MV showed still A. defectiva DNA by 16S-PCR so anti-infective treatment was continued for 6 six weeks after MV replacement. During 24 months, follow up after MV replacement the patient showed no evidence of MV dysfunction or endocarditis (Figure 4).

Figure 1: Segmental splenic infarct (red star) and liver hemangioma (blue arrow) seen on CT.

Figure 2: Transthoracic echocardiography showing vegetation on posterior (red star) and anterior mitral leaflet (blue arrow) in 4-chamber view (A) and 3-chamber view (B)

Figure 3: Trans-oesophageal echocardiography showing vegetation on posterior and anterior mitral leaflet (A) with accompanying severe mitral valve insufficiency (B)

Figure 4: Transthoracic echocardiography showing the biological mitral valve prothesis in the Follow up control, 24 months after surgery.