A Four-Year Silence: Late-Onset Stent-Graft Endocarditis Due to Rare Enterobacter hormaechei Diagnosed via Transesophageal Echocardiography

Abstract

Stent-graft infection (SGI) after thoracic endovascular aortic repair (TEVAR) is a rare but life-threatening complication. We report a case of a male patient who presented four years after TEVAR with systemic sepsis. At admission, laboratory investigations revealed a marked inflammatory response with a C-reactive protein (CRP) level of 212 mg/dL and a procalcitonin level of 23.30 progression. Diagnostic workup identified multidrug-resistant (MDR) Enterobacter hormaechei bacteremia. While transthoracic imaging was inconclusive, transesophageal echocardiography (TEE) confirmed a 6.6 x 5 mm mobile, fibrillar vegetation on the luminal surface of the aortic stent-graft, accompanied by severe aortic regurgitation. Following susceptibility results, the initial trimethoprim/sulfamethoxazole treatment was discontinued, and targeted intravenous gentamicin was initiated. Following the switch to gentamicin, a prompt therapeutic response was achieved, and inflammatory markers showed a significant downward trend. After multidisciplinary evaluation with the cardiovascular surgery department, a conservative management approach was adopted due to high operative risk. The patient remains under stable clinical follow-up. This case underscores the diagnostic necessity of TEE and the importance of targeted aminoglycosides in managing late-onset MDR prosthetic infections, especially when surgical intervention is not feasible.

Keywords

• Enterobacter hormaechei
• TEVAR
• stent-graft infection
• antibiotic resistance
• gentamicin.

Dört Yıllık Sessizlik: Transözofageal Ekokardiyografi ile Tanısı Konulan, Nadir Bir Patojen Olan Enterobacter hormaechei’ye Bağlı Geç Başlangıçlı Stent-Greft Endokarditi

Abstract

Torasik endovasküler aort onarımı (TEVAR) sonrası gelişen stent-greft enfeksiyonu (SGE), nadir görülen ancak hayati tehlike arz eden bir komplikasyondur. Bu yazıda, TEVAR işleminden dört yıl sonra sistemik sepsis tablosu ile başvuran bir erkek olgu sunulmaktadır. Başvuru anındaki laboratuvar incelemelerinde belirgin bir inflamatuar yanıt izlenmiştir. Tanısal süreçte yapılan kan kültürlerinde çoklu ilaç direnci (MDR) gösteren Enterobacter hormaechei üremesi saptanmıştır. Transözofageal ekokardiyografi (TEE) ile aortik stent-greftin lüminal yüzeyinde vejetasyon saptanmış ve eşlik eden ciddi aort yetmezliği izlenmiştir. Antibiyogram sonuçlarının ardından hedefe yönelik intravenöz gentamisin tedavisine başlanmış ve hızlı bir terapötik yanıt alınmıştır. Yüksek operatif risk nedeniyle konservatif yönetim kararı alınan hastanın klinik takibi stabil olarak devam etmektedir

Keywords

• Enterobacter hormaechei
• TEVAR
• stent-greft enfeksiyonu
• antibiyotik direnci
• gentamisin.

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