Disseminated abscesses from Treponema denticola diagnosed by next-generation sequencing: case report

Treponema denticola is a fastidious oral spirochete that is difficult to detect by conventional culture, and extraoral disseminated infections are exceedingly rare. We report a rare case of disseminated abscesses involving the liver, kidney and pararenal regions caused by T. denticola, highlighting the role of next-generation sequencing (NGS) in diagnosis of uncommon abscesses. A 50-year-old female presented with a refractory lumbar abscess. Initial conventional cultures were negative, and empirical antibiotic therapy was ineffective. Abdominal computed tomography (CT) revealed liver abscess, and multiple renal and hepatic abscess. After the initial NGS analysis of the abscess fluid led to an inappropriate treatment adjustment, repeat NGS analysis of a liver biopsy specimen identified T. denticola. The patient's condition was alleviated after the administration of a combined penicillin and doxycycline regimen and radical resection of the right hepatic lobe and kidney. This case confirms that T. denticola can cause severe systemic infection. The integration of advanced diagnostic technologies and multidisciplinary collaboration is crucial in managing infections of unknown origin.