Non-tuberculous mycobacteria: epidemiological pattern in a reference laboratory and risk factors associated with pulmonary disease.

The diseases caused by non-tuberculous mycobacteria (NTM), in both AIDS and non-AIDS populations, are increasingly recognized worldwide. Although the American Thoracic Society published the guidelines for diagnosis of NTM pulmonary disease (NTM-PD), the diagnosis is still difficult. In the first part of the study, we collected data on NTM isolates in the Mycobacteriology Laboratory of Careggi Hospital (Florence, Italy) and analysed the epidemiological data of NTM isolates. Then, to analyse the risk factors associated to NTM-PD, we studied the presence of ATS/IDSA criteria for NTM-PD in patients who had at least one positive respiratory sample for NTM and were admitted to the Infectious Disease Unit and the Section of Respiratory Medicine. We selected 88 patients with available full clinical data and, according to ATS/IDSA criteria, classified 15 patients (17%) as NTM-PD cases and 73 as colonized patients (83%). When comparing colonized and NTM-PD patients we did not find significant differences of age, gender and comorbidity. We observed that Mycobacterium avium and M. intracellulare were statistically associated with NTM-PD (P = 0·001) whereas M. xenopi was statistically associated with colonization. Although the number of studied patients is limited, our study did not identify risk factors for NTM-PD that could help clinicians to discriminate between colonization and disease. We underline the need of close monitoring of NTM-infected patients until the diagnosis is reasonably excluded. Further larger prospective studies and new biological markers are needed to identify new useful tools for the diagnosis of NTM-PD.

Successful tigecycline lock therapy in a Lactobacillus rhamnosus catheter-related bloodstream infection.

INTRODUCTION: Catheter-related bloodstream infections very often involve the premature removal of long-term intravascular devices (LTID). The antibiotic lock therapy (ALT) represents a conservative approach to the treatment of uncomplicated infections of tunneled LTID when catheter removal is not a feasible option. CASE REPORT: We present here the first reported case of tunneled LTID bloodstream infection due to a multidrug resistant Lactobacillus rhamnosus. The patient, who had large granular lymphocytic leukemia, was successfully treated with systemic tigecycline therapy and lock therapy. CONCLUSION: Our results confirm ALT as a valid catheter-salvage strategy for the treatment of CRBSIs in clinically stable patients when catheter removal is not a feasible option, tigecycline appear to be a good option.