Nakamura Yukihito, Hayakawa Manabu, Ishii Yoshihiro, Edamoto Masato, Sakaguchi Daisuke
General Practice, Miyazaki Prefectural Miyazaki Hospital, Miyazaki, JPN.
Cureus. 2025 Aug 28;17(8):e91167. doi: 10.7759/cureus.91167. eCollection 2025 Aug.
subsp. Pneumoniae (Kp) is a Gram-negative bacillus commonly encountered in clinical practice, often causing urinary tract infections and pneumonia. Kp includes classical strains (cKp) and hypervirulent strains (hvKp), the latter causing invasive syndromes, such as liver abscesses, endophthalmitis, and meningitis. HvKp is increasingly reported in East Asia, including Taiwan, and has occasionally been implicated in infectious aortic aneurysms (IAA). The hypermucoviscous phenotype of Kp (hmKp), identified by a positive string test, is strongly associated with hvKp. We report a case of sepsis caused by hmKp in a 65-year-old male. Although the patient initially responded to antibiotic therapy, low-grade fever and elevated inflammatory markers persisted. Reevaluation using contrast-enhanced computed tomography (CECT) revealed a delayed-onset IAA. The patient underwent emergency endovascular aneurysm repair (EVAR), followed by open aortic replacement (OAR), resulting in survival. This case highlights the importance of considering deep infections such as infectious aneurysms in patients with hmKp sepsis that fails to show expected clinical improvement despite appropriate treatment. Timely reevaluation with CECT is crucial for detecting life-threatening complications and enabling prompt, definitive management.
肺炎克雷伯菌亚种（Kp）是临床实践中常见的革兰氏阴性杆菌，常引起尿路感染和肺炎。Kp包括经典菌株（cKp）和高毒力菌株（hvKp），后者可引起侵袭性综合征，如肝脓肿、眼内炎和脑膜炎。在包括台湾在内的东亚地区，hvKp的报道日益增多，并且偶尔与感染性主动脉瘤（IAA）有关。通过拉丝试验阳性鉴定的Kp高黏液表型（hmKp）与hvKp密切相关。我们报告一例65岁男性由hmKp引起的败血症病例。尽管患者最初对抗生素治疗有反应，但低热和炎症标志物升高持续存在。使用对比增强计算机断层扫描（CECT）重新评估显示延迟发生的IAA。患者接受了急诊血管内动脉瘤修复术（EVAR），随后进行了开放性主动脉置换术（OAR），最终存活。该病例强调了对于尽管经过适当治疗但未能显示出预期临床改善的hmKp败血症患者，考虑深部感染如感染性动脉瘤的重要性。及时用CECT重新评估对于检测危及生命的并发症并实现迅速、明确的治疗至关重要。
