Bartonella Quintana培養陰性心内膜炎の1例．

A Case of Bartonella Quintana Culture-Negative Endocarditis.

• Sonika Patel
• Mary Elizabeth Richert
• Rachel White
• Tyler Lambing
• Paul Saleeb

抄録

背景 培養陰性の Bartonella quintana 心内膜炎は診断が難しく、高い死亡率と関連しています。Bartonella quintana感染症の診断確認には特殊な検査法が必要で、血清学的交差反応の割合が高いため、血清学的にBartonella henselae心内膜炎を特定することは困難です。本症例は、疫学的データ、組織学的検査、核酸増幅検査により診断された培養陰性のBartonella quintana心内膜炎の症例報告である。CASE REPORT ホームレス歴のある28歳男性が生産性咳嗽の悪化，体重減少，腹痛を訴えて入院した．経胸腔心エコー図（TTE）では肺弁植生と大動脈弁植生が数個認められた。入院経過は心原性ショックと敗血症性ショックを合併しており，第三次医療集中治療室への転院が必要であった．血液培養では細菌感染は陰性のままであったが，血清検査ではBartonella henselaeとBartonella quintana IgMとIgGが陽性であった．弁組織を用いた16SリボソームRNA（rRNA）の核酸増幅検査ではBartonella quintanaが診断された。結論 培養陰性のBartonella quintana心内膜炎のこの症例は、診断を確認するための診断用核酸増幅法の使用を実証している。

BACKGROUND Culture-negative Bartonella quintana endocarditis is challenging to diagnose and is associated with high mortality rates. Diagnostic confirmation of Bartonella quintana infection requires specialized assays, as identifying Bartonella henselae endocarditis by serology can be difficult due to the high rate of serological cross-reactivity. This is a case report of culture-negative Bartonella quintana endocarditis that was diagnosed with epidemiologic data, histology, and nucleic acid amplification testing. CASE REPORT A 28-year-old man with a history of homelessness was admitted to hospital with worsening productive cough, weight loss, and abdominal pain. A transthoracic echocardiogram (TTE) showed pulmonary valve vegetation and several aortic valve vegetations. His hospital course was complicated by cardiogenic shock and septic shock requiring transfer to a tertiary care medical intensive care unit. Although blood cultures remained negative for bacterial infection, serology testing was positive for Bartonella henselae and Bartonella quintana IgM and IgG. Nucleic acid amplification testing for 16S ribosomal RNA (rRNA) using valve tissue was diagnostic for Bartonella quintana. CONCLUSIONS This case of culture-negative Bartonella quintana endocarditis demonstrates the use of diagnostic nucleic acid amplification methods to confirm the diagnosis.