Differentially culturable tubercle bacteria dynamics during standard anti-tuberculosis treatment: A prospective cohort study.

This study aimed to evaluate the dynamics of culture filtrate dependent subpopulations of Mycobacterium tuberculosis in a prospective cohort study following 17 patients through a standard 6-month anti-tuberculosis regimen, performing monthly sputum collection. We performed the limiting dilution method with culture filtrate supplementation of liquid media in pre- and post-treatment sputum samples to assess the bacillary load and to evaluate the Mycobacterium tuberculosis subpopulation dynamics within the 6-months standard anti-tuberculosis regimen. We found that supplementation increased the bacillary load by 30% in pre-treatment samples (p = 0.0005) and 35% in samples after one month of treatment (p = 0.0977). We found a weak linear correlation between the decrease of Mycobacterium tuberculosis growth in liquid media with and without culture filtrate supplementation (ρ = 0.54; p = 0.026). None of the patients had bacilli recovery after two months of treatment. Our study constitutes the first follow-up regarding Mycobacterium tuberculosis subpopulation dynamics throughout a standard 6-month anti-tuberculosis treatment and also supports the use of culture filtrate to increase bacillary load in liquid media. Moreover, it highlights that any new treatment regimens should test the efficacy of the drugs in all Mycobacterium tuberculosis subpopulations.

Sputum sample collected over a period of 5 h: A reliable procedure for early bactericidal activity studies.

Our study was designed to test the hypothesis that an early morning sputum may be sufficient for calculation of early bactericidal activity (EBA). Patients underwent sputum collection randomly (spot, 5 h and 12 h) in consecutive days. The median CFU count in the spot samples group was 5.67 log10 CFU/mL compared to 6.17 log10 CFU/mL in 5 h and 6.23 log10 CFU/mL in 12 h samples. Inter-patient comparison showed low coefficient of variation for both 12 h (11%) and 5 h samples (10%). Intrapatient samples analysis demonstrated that the median bacillary load variation (0.037 log10 CFU/mL and 0.022 log10 CFU/mL for 5 and 12 h samples respectively) was comparable to the other EBA studies and did not vary significantly from one day of collection to another. We concluded that 5 h pooled sputum when collected appropriately in the morning can be sufficient for calculation of EBA.

The impact of ocular tuberculosis on vision after two months of intensive therapy.

Tuberculosis is an infectious disease of global importance with major economic and social burden accounting for 25% of all avoidable deaths in developing countries. Extrapulmonary involvement may occur either in association with clinically apparent pulmonary tuberculosis or in isolation. This cross-sectional descriptive study aimed to evaluate the impact of ocular tuberculosis in visual acuity at baseline and after two months of intensive anti-tuberculous therapy. A sample of 133 pulmonary tuberculosis patients, seven disseminated tuberculosis, and three pleural tuberculosis patients was evaluated. All patients underwent routine ophthalmic evaluation, including assessment of visual acuity, biomicroscopy, applanation tonometry, indirect ophthalmoscopy, and fluorescent angiography as appropriate. None of the patients had impaired visual acuity due to tuberculosis. A rate of 4.2% (6/143) of ocular involvement was found. None of the patients with ocular involvement were HIV-infected. Of the six patients with ocular involvement, five met the diagnostic criteria for probable and one for possible ocular lesions. As for the type of ocular lesions, two patients had bilateral findings: one had sclerouveitis and the second had choroidal nodules. The other four patients presented with unilateral lesions: peripheral retinal artery occlusion in the right eye (one case), choroidal nodules in the left eye (one case), and choroidal nodules in the right eye (two cases). Patients progressed favorably after two month of intensive therapy, with no significant reduction in vision.