Pharmacokinetic-Pharmacodynamic Determinants of Clinical Outcomes for Rifampin-Resistant Tuberculosis: A Multisite Prospective Cohort Study

BACKGROUND

Rifampin-resistant and/or multidrug-resistant tuberculosis (RR/MDR-TB) treatment requires multiple drugs, and outcomes remain suboptimal. Some drugs are associated with improved outcome. It is unknown whether particular pharmacokinetic-pharmacodynamic relationships predict outcome.

METHODS

Adults with pulmonary RR/MDR-TB in Tanzania, Bangladesh, and the Russian Federation receiving local regimens were enrolled from June 2016 to July 2018. Serum was collected after 2, 4, and 8 weeks for each drug's area under the concentration-time curve over 24 hours (AUC0-24). Quantitative susceptibility of the M. tuberculosis isolate was measured by minimum inhibitory concentrations (MICs). Individual drug AUC0-24/MIC targets were assessed by adjusted odds ratios (ORs) for favorable treatment outcome, and hazard ratios (HRs) for time to sputum culture conversion. K-means clustering algorithm separated the cohort of the most common multidrug regimen into 4 clusters by AUC0-24/MIC exposures.

RESULTS

Among 290 patients, 62 (21%) experienced treatment failure, including 30 deaths. Moxifloxacin AUC0-24/MIC target of 58 was associated with favorable treatment outcome (OR, 3.75; 95% confidence interval, 1.21-11.56; P = .022); levofloxacin AUC0-24/MIC of 118.3, clofazimine AUC0-24/MIC of 50.5, and pyrazinamide AUC0-24 of 379 mg × h/L were associated with faster culture conversion (HR >1.0, P < .05). Other individual drug exposures were not predictive. Clustering by AUC0-24/MIC revealed that those with the lowest multidrug exposures had the slowest culture conversion.

CONCLUSIONS

Amidst multidrug regimens for RR/MDR-TB, serum pharmacokinetics and M. tuberculosis MICs were variable, yet defined parameters to certain drugs-fluoroquinolones, pyrazinamide, clofazimine-were predictive and should be optimized to improve clinical outcome.

CLINICAL TRIALS REGISTRATION

NCT03559582.

A Geospatial Bibliometric Review of the HIV/AIDS Epidemic in the Russian Federation

Background: Increasing rates of HIV/AIDS in Eastern Europe and Central Asia contrast global trends, but the scope of HIV/AIDS research originating from Russian Federation and countries of the former Soviet Union has not been quantified.

Methods: We searched six major scientific databases in Russian and English languages with medical subject heading terms “HIV” or “AIDS” and “Russia” or “Soviet Union” from 1991 to 2016. Each abstract indexed was reviewed and tagged for 25 HIV/AIDS research themes, location of research focus and first author.

Results and Discussion: A total of 2,868 articles were included; 2,156 (75.1%) and 712 (24.8%) described research in the Russian Federation and countries of the former Soviet Union, respectively. There were 15 publications per million population in Russian Federation. Federal districts of the Russian Federation with the highest rates of HIV had the most limited publications. An interactive web-map with time-lapse features and links to primary literature was created using ArcGIS^® technology [http://arcg.is/2FUIJ5v].

Conclusion: We found a lower than expected publication rate in the Russian Federation relative to rising HIV prevalence. The greatest deficits were in the most HIV burdened regions in the Russian Federation. Our findings highlight opportunities for new research strategies and public health efforts among key populations and subnational regions.

MEDICAL AND SOCIAL CHARACTERISTICS OF PATIENTS WITH TUBERCULOSIS OF CHILDREN IN CONDITIONS OF SOCIAL INSUFFICIENCY IN THE IRKUTSK REGION

Background. In cases of tuberculosis in children, contacts with patients with drug-resistant forms are often detected. Treatment and prevention of the disease is based on these data and adherence to treatment. Aims. To analyze the social status of the family of children with tuberculosis, clinical forms and drug resistance of MBT in patients who are sources of infection in the outbreak for adequate planning of preventive treatment of contact and treatment of children with tuberculosis. Materials and methods. The study involved 150 children with tuberculosis treated in a hospital in 2009–2012 and 142 children – in 2015–2017. We studied social factors and drug resistance of Mycobacterium tuberculosis in adult patients – sources to child transmission. Drug resistance of MBT cultures was determined by Löwenstein – Jensen me- dium and automated system BACTEC MGIT 960. Results. 50.0 % of children with tuberculosis are patients of preschool age, 33.0 % of children aged under 3 years. From 2009–2012 to 2015–2017 the proportion of socially disadvantaged families fell from 68.0 % to 45.1 %. At the same time the proportion of children with tuberculosis, contracted from a known contact decreased from 70.0 % to 57.0 %. Often children get infected from mother or from several close relatives (mother, father, grandfather, grandmother), TB patients source of infection of children are often diagnosed with infiltrative (21.9–38.3 %) and fibro-cavernous tuberculosis (17.0–21.0 %). To 2015–2017 multi-drug resistance in the nidi was recorded at 52.2 %. The development of tuberculosis in children was facilitated by the defects of preventative measures: absence of BCG vaccination (from 9.0 to 14.0 % of children), the absence of preventive treatment (55.3–67.5 %).

Undertreated HIV and drug-resistant tuberculosis at a referral hospital in Irkutsk, Siberia

SETTING

A referral hospital for tuberculosis (TB) in Irkutsk, the Russian Federation.

OBJECTIVE

To describe disease characteristics, treatment and hospital outcomes of TB-HIV (human immunodeficiency virus).

DESIGN

Observational cohort of HIV-infected patients admitted for anti-tuberculosis treatment over 6 months.

RESULTS

A total of 98 patients were enrolled with a median CD4 count of 147 cells/mm(3) and viral load of 205 943 copies/ml. Among patients with drug susceptibility testing (DST) results, 29 (64%) were multidrug-resistant (MDR), including 12 without previous anti-tuberculosis treatment. Nineteen patients were on antiretroviral therapy (ART) at admission, and 10 (13% ART-naïve) were started during hospitalization. Barriers to timely ART initiation included death, in-patient treatment interruption, and patient refusal. Of 96 evaluable patients, 21 (22%) died, 14 (15%) interrupted treatment, and 10 (10%) showed no microbiological or radiographic improvement. Patients with a cavitary chest X-ray (aOR 7.4, 95%CI 2.3-23.7, P = 0.001) or central nervous system disease (aOR 6.5, 95%CI 1.2-36.1, P = 0.03) were more likely to have one of these poor outcomes.

CONCLUSION

High rates of MDR-TB, treatment interruption and death were found in an HIV-infected population hospitalized in Irkutsk. There are opportunities for integration of HIV and TB services to overcome barriers to timely ART initiation, increase the use of anti-tuberculosis regimens informed by second-line DST, and strengthen out-patient diagnosis and treatment networks.

Administrative interventions associated with increased initiation on antiretroviral therapy in Irkutsk, Siberia

A bundle of initiatives to integrate human immunodeficiency virus (HIV) and tuberculosis (TB) services was assessed for the impact on antiretroviral therapy (ART) initiation at a TB referral hospital in Irkutsk, Russian Federation, from February 2014 to December 2015. The ART initiation rates in 166 ART-naïve patients undergoing anti-tuberculosis treatment (34.1% with multidrug or extensively drug-resistant TB) increased significantly from 14 (17%) pre-intervention to 44 (54%) post-intervention (P < 0.001). A survey of TB hospital staff identified administrative prioritisation as the most important initiative for increasing ART initiation.

Primary multidrug-resistant Mycobacterium tuberculosis in 2 regions, Eastern Siberia, Russian Federation

Of 235 Mycobacterium tuberculosis isolates from patients who had not received tuberculosis treatment in the Irkutsk oblast and the Sakha Republic (Yakutia), eastern Siberia, 61 (26%) were multidrug resistant. A novel strain, S 256, clustered among these isolates and carried eis-related kanamycin resistance, indicating a need for locally informed diagnosis and treatment strategies.