Detection of Gram-Ghost Bacilli and Additional Ziehl-Neelsen Stain for the Early Diagnosis of Driveline Infection: A Case Report.

Abstract

Background: Driveline infections (DLI) caused by nontuberculous mycobacteria (NTM) in patients with implantable left ventricular assist devices (iLVAD) are rare but fatal, requiring early diagnosis and appropriate treatment. Herein, we present a rare case of DLI caused by Mycobacterium chelonae, which was promptly diagnosed using Gram stain and Ziehl-Neelsen stain and followed a favorable clinical course.

Case presentation: A 51-year-old man with an iLVAD complicated by DLI was admitted to our center. He had no fever but had a slight ache and rash around the driveline exit site on admission. The wound condition gradually deteriorated with increasing purulent discharge from the driveline exit site and an elevated inflammatory response, despite daily irrigation. Gallium scintigraphy led to the diagnosis of deep DLI, followed by surgical debridement and omental flap transposition with driveline translocation. The Gram stain of the purulent discharge from the surgical site showed unstained bacilli (Gram-neutral, neither positive nor negative) along with leukocyte phagocytosis. Additionally, the Ziehl-Neelsen stain was positive. NTM was suspected after confirming the negative polymerase chain reaction for M. tuberculosis. Antibiotic therapy was switched to a specific regimen for skin and soft tissue infections caused by NTM. After identifying M. chelonae, antibiotic therapy was switched to a more specific regimen (clarithromycin and doxycycline) for M. chelonae according to the susceptibility test results. The patient was discharged after 3 months without infection recurrence.

Conclusions: Detecting Gram-ghost bacilli and using an additional Ziehl-Neelsen stain can be beneficial for the early diagnosis of repeated DLI with unknown etiology.