Characteristics distinguishing disseminated Mycobacterium tuberculosis (MTB) and non-tuberculous mycobacterial (NTM) infection in HIV patients
© Bailey et al; licensee BioMed Central Ltd. 2008
Published: 10 November 2008
Purpose of the study
The characteristics that distinguish disseminated MTB and NTM infection in patients with advanced HIV disease remain poorly studied. We aim to describe clinical, laboratory and radiological features of MTB and NTM and identify discriminatory findings.
We conducted a retrospective case note review of all patients with culture-proven disseminated mycobacterial disease at a UK centre from 2005–2007. Patients with infection in ≥2 non-contiguous sites, or positive blood or bone marrow cultures, were included and stratified by causative pathogen. Categorical data were analysed by Fisher's exact test and non-categorical data by rank sum test.
Summary of results
MTB (n = 21)
NTM (n = 10)
Prior/concurrent AIDS-defining illness (%)
Median CD4 count at MTB/NTM diagnosis, cells/mm3 (IQR)
On HAART at MTB/NTM diagnosis (%)
Parenchymal lung disease on CT scan* (%)
Thoracic/abdominal lymphadenopathy on CT or US scan* (%)
Positive AFB smear on sputum/BAL* (%)
Positive sputum/BAL culture* (%)
Positive blood culture* (%)
Positive bone marrow culture and/or histology* (%)
Clinical and laboratory characteristics of patients with MTB and NTM overlap. In patients with suspected disseminated mycobacterial infection, prior or concurrent AIDS defining illnesses and recent HAART initiation favour NTM, while >100 CD4 T-cells/mm3 and parenchymal lung disease are suggestive of MTB.
This article is published under license to BioMed Central Ltd.