Institute of Medical Microbiology, University Hospital Münster, Münster, Germany.
Department of Cardiology, University Hospital Münster, Münster, Germany.
BMC Infect Dis. 2022 Aug 17;22(1):696. doi: 10.1186/s12879-022-07590-1.
Capnocytophaga canimorsus, a Gram-negative rod, belongs to the Flavobacteriaceae family and colonizes the oropharynx of dogs and cats. Infections with C. canimorsus are rare and can induce a systemic infection with a severe course of the disease. So far, only five case reports of C. canimorsus infections associated with Waterhouse-Friderichsen Syndrome (WFS) have been reported with only two of the patients having a history of splenectomy.
Here, we report a fatal case of WFS due to C. canimorsus bacteremia and mycetal superinfection in a 61-year-old female asplenic patient. Despite extensive therapy including mechanical ventilation, antibiotic coverage with meropenem, systemic corticosteroids medication, vasopressor therapy, continuous renal replacement therapy, therapeutic plasma exchange, multiple transfusions of blood products and implantation of a veno-arterial extracorporeal membrane oxygenation the patient died 10 days after a dog bite. The autopsy showed bilateral hemorrhagic necrosis of the adrenal cortex and septic embolism to heart, kidneys, and liver. Diagnosis of C. canimorsus was prolonged due to the fastidious growth of the bacteria.
The occurrence of a severe sepsis after dog bite should always urge the attending physician to consider C. canimorsus as the disease-causing pathogen. A therapeutic regimen covering C. canimorsus such as aminopenicillins or carbapenems should be chosen. However, despite maximum therapy, the prognosis of C. canimorsus-induced septic shock remains very poor. Asplenic or otherwise immunocompromised patients are at higher risk for a severe course of disease and should avoid exposure to dogs and cats and consider antibiotic prophylaxis after animal bite.
噬二氧化碳噬纤维菌（Capnocytophaga canimorsus）是一种革兰氏阴性杆菌，属于黄杆菌科，定植于犬猫的口腔。感染噬二氧化碳噬纤维菌的情况较为罕见，但可引起全身性感染，病情严重。迄今为止，仅有 5 例与噬二氧化碳噬纤维菌感染相关的噬二氧化碳噬纤维菌感染相关的噬二氧化碳噬纤维菌感染（Waterhouse-Friderichsen 综合征，WFS）病例报告，其中仅有 2 例患者有脾切除术史。
本文报告了一例 61 岁女性无脾患者因噬二氧化碳噬纤维菌菌血症和真菌性二重感染导致致命性 WFS 的病例。尽管进行了广泛的治疗，包括机械通气、美罗培南覆盖的抗生素治疗、全身皮质类固醇治疗、升压治疗、连续肾脏替代治疗、治疗性血浆置换、多次输血和植入静脉-动脉体外膜肺氧合，但患者在被狗咬伤 10 天后死亡。尸检显示双侧肾上腺皮质出血性坏死和心、肾、肝的败血症性栓塞。由于细菌的生长要求苛刻，导致噬二氧化碳噬纤维菌的诊断被延长。
被狗咬伤后发生严重败血症时，临床医生应始终考虑噬二氧化碳噬纤维菌为致病病原体。应选择覆盖噬二氧化碳噬纤维菌的治疗方案，如氨青霉素或碳青霉烯类药物。然而，尽管进行了最大程度的治疗，噬二氧化碳噬纤维菌引起的感染性休克的预后仍然非常差。无脾或免疫功能低下的患者发生严重疾病的风险更高，应避免接触犬猫，并在被动物咬伤后考虑抗生素预防。
