A Case Report of Infective Endocarditis with Failure of the Empirical Treatment—Q Fever Endocarditis Diagnosed by Metagenomic Next-Generation Sequencing

BACKGROUND: Infective endocarditis (IE) can be caused by a variety of pathogens. Endocarditis due to the Coxiella burnetii (C. burnetii) infection is common in patients with negative blood culture results and usually occurs in patients with previous valvular heart disease, impaired immune function, and during pregnancy. The diagnosis is difficult based on the conventional diagnostic method, and serious adverse outcomes may occur in the case of delayed diagnosis. CASE REPORT: In the present study, a case of a 43-year-old male patient with previous valvular heart disease was reported. The patient was admitted with a diagnosis of IE, but the etiology was unclear. Accurate diagnosis and treatment were achieved by combining metagenomic next-generation sequencing (mNGS) with Q fever serological antibody assay. CONCLUSION: Metagenomic next-generation sequencing has been increasingly applied in clinical practice in recent years to detect the DNA or RNA in samples, and this could play a decisive role in the etiological diagnosis of some infectious diseases.