Hayk Davtyan

Dr. Hayk Davtyan

Tuberculosis Research and Prevention Center
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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RBRegina Banu
Regina Banu
JAJorge Matheu Alvarez
Jorge Matheu Alvarez
ARAnthony J. Reid
Anthony J. Reid
Wendemagegn EnbialeWendemagegn Enbiale
Wendemagegn Enbiale
ALAppiah-Korang Labi
Appiah-Korang Labi
HSHeike Schmitt
Heike Schmitt
Infections by Extended-Spectrum Beta-Lactamase producing Escherichia coli (ESBL-Ec) are on the increase in Ghana, but the level of environmental contamination with this organism, which may contribute to growing Antimicrobial Resistance (AMR), is unknown. Using the WHO OneHealth Tricycle Protocol, we investigated the contamination of E. coli (Ec) and ESBL-Ec in two rivers in Ghana (Odaw in Accra and Okurudu in Kasoa) that receive effluents from human and animal wastewater hotspots over a 12-month period. Concentrations of Ec, ESBL-Ec and percent ESBL-Ec/Ec were determined per 100 mL sample. Of 96 samples, 94 (98%) were positive for ESBL-Ec. concentrations per 100 mL (MCs100) of ESBL-Ec and %ESBL-Ec from both rivers were 4.2 × 104 (IQR, 3.1 × 103–2.3 × 105) and 2.79 (IQR, 0.96–6.03), respectively. MCs100 were significantly lower in upstream waters: 1.8 × 104 (IQR, 9.0 × 103–3.9 × 104) as compared to downstream waters: 1.9 × 106 (IQR, 3.7 × 105–5.4 × 106). Both human and animal wastewater effluents contributed to the increased contamination downstream. This study revealed high levels of ESBL-Ec in rivers flowing through two cities in Ghana. There is a need to manage the sources of contamination as they may contribute to the acquisition and spread of ESBL-Ec in humans and animals, thereby contributing to AMR.
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25 April 2020 in BMC Pulmonary Medicine
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VKVahe Khachadourian
Vahe Khachadourian
NTNune Truzyan
Nune Truzyan
AHArusyak Harutyunyan
Arusyak Harutyunyan
VPVarduhi Petrosyan
Varduhi Petrosyan
HDHayk Davtyan
Hayk Davtyan
Michael ThompsonMichael Thompson
Michael Thompson
Background: WHO’s directly observed therapy (DOT) strategy for tuberculosis (TB) treatment depends upon a well–organized healthcare system. This study sought to evaluate the effectiveness of self-administered drug intake supported by a family member versus in-clinic DOT.Methods: This open–label, nationally-representative stratified cluster randomized controlled non–inferiority trial with two parallel equal arms involved drug–susceptible pulmonary TB patients in the continuation treatment phase. We randomly assigned outpatient–TB–centres (52 clusters) to intervention and control arms. The intervention included an educational/counseling session to enhance treatment adherence; weekly visits to outpatient–TB–centres to receive medication, and daily SMS medication reminders and phone calls to track adherence and record side effects. Controls followed clinical DOT at Outpatient–TB–centres. Both groups participated in baseline and 4–5 months follow–up surveys. The trial’s non–inferiority comparisons include: treatment success as the clinical (primary) outcome and medication adherence (self–reported), knowledge, depressive symptoms, stigma, quality of life, and social support as non–clinical (secondary) outcomes.Results: Per–protocol analysis showed that the intervention (n = 187) and control (n = 198) arms achieved successful treatment outcome of 92.0 and 92.9%, respectively, indicating that the treatment success in the intervention group was non–inferior to DOT. Knowledge, depression, stigma, quality of life, and social support also showed non–inferiority, demonstrating substantial improvement over time for knowledge (change in the intervention = 1.05: 95%CL (0.49, 1.60); change in the control = 1.09: 95%CL (0.56, 1.64)), depression score (change in the intervention = − 3.56: 95%CL (− 4.99, − 2.13); change in the control = − 1.88: 95% CL (− 3.26, − 0.49)) and quality of life (change in the intervention = 5.01: 95%CL (− 0.64, 10.66); change in the control = 7.29: 95%CL (1.77, 12.81)). The intervention resulted in improved treatment adherence.Conclusions: This socially empowering alternative strategy might be a preferable alternative to DOT available to patients in Armenia and in other countries. Further research evaluating cost effectiveness of the intervention and generalizability of the results is warranted.Trial registration: Clinicaltrials.gov:NCT02082340, March 10, 2014.

BABenjamin Asamoah
Benjamin Asamoah
ALAppiah-Korang Labi
Appiah-Korang Labi
HGHimanshu A. Gupte
Himanshu A. Gupte
HDHayk Davtyan
Hayk Davtyan
GPGeorgette Marfo Peprah
Georgette Marfo Peprah
PSPaul Sekyere-Nyantakyi
Paul Sekyere-Nyantakyi
Management of urinary tract infections is challenged by increasing antimicrobial resistance (AMR) worldwide. In this study, we describe the trends in antimicrobial resistance of uropathogens isolated from the largest private sector laboratory in Ghana over a five-year period. We reviewed positive urine cultures at the MDS Lancet Laboratories from 2017 to 2021. The proportions of uropathogens with antimicrobial resistance to oral and parenteral antimicrobials recommended by the Ghana standard treatment guidelines were determined. The proportion of multi-drug resistant isolates, ESBL and carbapenemase-producing phenotypes were determined. Of 94,134 urine specimens submitted for culture, 20,010 (22.1%) were culture positive. Enterobacterales was the most common group of organisms, E. coli (70.6%) being the most common isolate and Enterococcus spp. the most common gram-positive (1.3%) organisms. Among oral antimicrobials, the highest resistance was observed to ciprofloxacin (62.3%) and cefuroxime (60.2%) and the least resistance to fosfomycin (1.9%). The least resistance among parenteral antimicrobials was to meropenem (0.3%). The highest multi-drug resistance levels were observed among Klebsiella spp. (68.6%) and E. coli (64.0%). Extended-spectrum beta-lactamase (ESBL) positivity was highest in Klebsiella spp. (58.6%) and E. coli (50.0%). There may be a need to review the Ghana standard treatment guidelines to reflect increased resistance among uropathogens to recommended antimicrobials.

MAMakhliyo Abdusalomova
Makhliyo Abdusalomova
ODOlga Denisiuk
Olga Denisiuk
HDHayk Davtyan
Hayk Davtyan
Jamshid GadoevJamshid Gadoev
Jamshid Gadoev
BABarno Abdusamatova
Barno Abdusamatova
ASAbduvohid Sodikov
Abduvohid Sodikov
The treatment of childhood tuberculosis can be challenging due to the lack of pediatric drug formulations and monitoring of drug-toxicity in routine settings. There are no published studies from Uzbekistan on the adverse drug reactions (ADR) associated with anti-tuberculosis treatment in children. In this study, we aimed to investigate the ADR associated with anti-tuberculosis treatment in children. This was a cohort study using secondary program data of children treated at the city and regional tuberculosis clinics in Tashkent, Uzbekistan. Of the 302 patients evaluated, 135 (44.7%) reported ADR. New tuberculosis was registered in 277 (92%) patients and 262 (87%) had extrapulmonary tuberculosis. Factors associated with ADR included treatment at a regional hospital (adjusted odds ratio, aOR = 1.75; p = 0.026), female sex (aOR = 2.2; p = 0.004), and treatment with second-line drugs (aOR = 8.82; p < 0.001). The most common ADRs were gastrointestinal disorders (28.5%) followed by hepatitis (8.9%) and dermatologic reactions (8.6%). Most of the ADRs were mild (55.6%) or moderate (43.7%), only one child had severe ADR. Patients with the identified risk factors should be closely monitored during the treatment. We also recommend expansion of ADR surveillance throughout the country for more representative data in the future.

14 January 2021 in Monaldi Archives for Chest Disease
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TATeona Avaliani
Teona Avaliani
YSYuliia Sereda
Yuliia Sereda
HDHayk Davtyan
Hayk Davtyan
Nestani TukvadzeNestani Tukvadze
Nestani Tukvadze
TTTamar Togonidze
Tamar Togonidze
AHArax Hovhannesyan
Arax Hovhannesyan
Tuberculosis treatment is challenging, especially among people with drug-resistant forms of tuberculosis. The introduction of fully oral modified short treatment regimen has a great potential to shorten duration of treatment, improve safety and ultimately increase treatment success rate. In 2019 Georgia has piloted the modified fully oral shorter treatment regimen in a routine programmatic condition. Our study aimed to evaluate effectiveness and safety of the modified shorter treatment regimen in Georgia among the first 25 consecutively enrolled patients with rifampicin-resistant tuberculosis with proven sensitivity to fluoroquinolone and without prior exposure to second-line tuberculosis drugs. Regimen consisted of 9-month daily administration of bedaquilline, linezolid, levofloxacin, clofazimine and cycloserine. Study patients were enrolled between March-August 2019. We used a national electronic surveillance system, medical records and active TB drug-safety monitoring and management database to extract study related data. The mean age of the study participants was 48 years, 68% were male, 8% were HIV positive, 16% had diabetes and 12% tested positive for hepatitis C infection. The median time to culture conversion among 16 patients who were culture positive at treatment initiation was 1.0 (95% CI: 1.0-2.0) month. Of those, by the end of treatment 15 patients converted to negative. Out of the 25 patients in the study cohort 22 (88%) had successful treatment outcome, one patient (4%) died and two (8%) were lost to follow up. The regimen was largely well tolerated. Three patients (12%) experienced serious adverse events, of which in two cases were possibly related to TB drugs in the regimen. Seven patients developed adverse events of interest in eight instances, including musculoskeletal (twice), psychiatric, gastrointestinal disorders, hepatotoxicity, peripheral neuropathy, cardiotoxicity and myelosuppression (once each). In four patients (16%) the duration of the treatment was extended beyond nine months due to insufficient radiological improvements. Our findings demonstrate that good treatment outcomes are achievable in people with fluoroquinolone-sensitive tuberculosis within routine programmatic conditions using fully oral modified short treatment regimen. The extensive use of fully oral modified shorter treatment regimen in Georgia and other high priority countries in the World Health Organization European Region is warranted.

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Gerald MboowaGerald Mboowa
Gerald Mboowa
Dickson AruhomukamaDickson Aruhomukama
Dickson Aruhomukama
ISIvan Sserwadda
Ivan Sserwadda
FKFreddy Kitutu
Freddy Kitutu
HDHayk Davtyan
Hayk Davtyan
HKHenry Mawerere Kajumbula
Henry Mawerere Kajumbula
Antimicrobial Resistance (AMR) and Healthcare Associated Infections (HAIs) are major global public health challenges in our time. This study provides a broader and updated overview of AMR trends in surgical wards of Mulago National Referral Hospital (MNRH) between 2014 and 2018. Laboratory data on the antimicrobial susceptibility profiles of bacterial isolates from 428 patient samples were available. The most common samples were as follows: tracheal aspirates (36.5%), pus swabs (28.0%), and blood (20.6%). Klebsiella (21.7%), Acinetobacter (17.5%), and Staphylococcus species (12.4%) were the most common isolates. The resistance patterns for different antimicrobials were: penicillins (40–100%), cephalosporins (30–100%), β-lactamase inhibitor combinations (70–100%), carbapenems (10–100%), polymyxin E (0–7%), aminoglycosides (50–100%), sulphonamides (80–100%), fluoroquinolones (40–70%), macrolides (40–100%), lincosamides (10–45%), phenicols (40–70%), nitrofurans (0–25%), and glycopeptide (0–20%). This study demonstrated a sustained increase in resistance among the most commonly used antibiotics in Uganda over the five-year study period. It implies ongoing hospital-based monitoring and surveillance of AMR patterns are needed to inform antibiotic prescribing, and to contribute to national and global AMR profiles. It also suggests continued emphasis on infection prevention and control practices (IPC), including antibiotic stewardship. Ultimately, laboratory capacity for timely bacteriological culture and sensitivity testing will provide a rational choice of antibiotics for HAI.
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