Fluoroquinolone-resistant latent tuberculosis infection: A literature review and case series of 5 patients treated with linezolid monotherapy

Abstract

Latent tuberculosis infection (LTBI) constitutes an important public health problem because of risk of progression to TB disease. Effective treatment of multi-drug resistant (MDR) LTBI would prevent progression to MDR TB disease, which would improve patient and public health outcomes. The majority of MDR LTBI treatment studies have focused on the use of fluoroquinolone-based antibiotic regimens. Options for and experience in the treatment of fluoroquinolone-resistant MDR LTBI are limited in the published literature and not comprehensively addressed in current guidelines. In this review, we share our experience with the treatment of fluoroquinolone-resistant MDR LTBI with linezolid. We discuss treatment options for MDR TB that provide context for predicting effective MDR LTBI treatment, with a focus on the microbiologic and pharmacokinetic properties of linezolid that support its use. We then summarize the evidence for treatment of MDR LTBI. Finally, we present our experiences treating fluoroquinolone-resistant MDR LTBI with linezolid with an emphasis on dosing considerations to optimize efficacy and minimize potential toxicities.

Keywords: Latent tuberculosis infection; Linezolid; Multidrug-resistant tuberculosis.

Fig. 1

Complete blood count monitoring during therapy in case series #1. White blood cell count (WBC), Hemoglobin, and platelet count remained normal throughout therapy. Blood counts were monitored at two weeks and then monthly throughout the course of treatment without any evidence of cytopenia. A comprehensive metabolic panel was performed 4 months into therapy without evidence of impaired renal function or liver inflammation.