Mycobacterial central venous catheter tunnel infection: a difficult problem

Area of Science:

• Infectious Diseases
• Hematology
• Oncology

Background:

• Central venous catheters (CVCs), such as Hickman-Broviac catheters, are crucial for immunosuppressed patients with hematological malignancies undergoing high-dose chemotherapy and bone marrow transplantation (BMT).
• Non-tuberculous mycobacterial (NTM) infections are a rare but serious complication associated with CVCs, particularly in immunocompromised individuals.

Observation:

• This study reports on NTM infections occurring at the tunnel site of Hickman-Broviac catheters in patients with hematological malignancies.
• A unique aspect observed was the development of tunnel site NTM infections even after the removal of the CVCs.
• Identified pathogens included Mycobacterium chelonae (a known cause) and Mycobacterium haemophilum (newly reported in this context).

Findings:

• The study details three cases of NTM tunnel infections: one with M. chelonae and two with M. haemophilum.
• Effective treatment necessitates early, wide surgical excision of the infected tunnel site combined with prolonged antibiotic therapy.
• Recurrence of infection was observed in two of the three cases despite these interventions.

Implications:

• These findings highlight the challenge in treating NTM tunnel infections, even post-catheter removal, in immunocompromised patients.
• Close collaboration with microbiology laboratories is essential for the accurate diagnosis of these fastidious organisms.
• Empirical antibiotic strategies should consider M. chelonae and M. haemophilum, necessitating the inclusion of drugs active against these specific mycobacteria.