A Ten-Year Trend in the Antimicrobial Sensitivity Pattern of Salmonella spp. Isolated from Bloodstream Infections: A Retrospective Observational Study.

Dr. Anand  Acharya; Dr. Nageswara  Rao T; Dr.Bhavika D

doi:10.51168/sjhrafrica.v6i12.2336

Authors

Dr. Anand Acharya Dean and Professor, Department of Pharmacology, Konaseema Institute of Medical Sciences, Amalapuram, Andhra Pradesh, India
Dr. Nageswara Rao T Associate Professor, Department of Pharmacology, Konaseema Institute of Medical Sciences and Research Foundation, Amalapuram, Andhra Pradesh, India
Dr. Bhavika.D Associate Professor, Department of Pharmacology, Government Medical College and General Hospital, Quthbullapur, Telangana, India

DOI:

https://doi.org/10.51168/sjhrafrica.v6i12.2336

Keywords:

Salmonella Typhi, bloodstream infection, antimicrobial resistance, fluoroquinolone, ceftriaxone

Abstract

Background:

Bloodstream infections (BSIs due to Salmonella spp.) remain a significant public-health concern in endemic regions. The evolving antimicrobial resistance (AMR) patterns among typhoidal and non-typhoidal Salmonella challenge empirical treatment strategies. This study evaluated ten-year trends in antimicrobial susceptibility of Salmonella isolates from bloodstream infections.

Methods:

A retrospective observational analysis was performed at a tertiary-care hospital from 2014 to 2023. A total of 200 non-duplicate Salmonella isolates recovered from blood cultures were included. Species identification was carried out using standard biochemical methods and MALDI-TOF mass spectrometry. Antimicrobial susceptibility testing was performed by disk diffusion and E-test in accordance with CLSI guidelines. Temporal trends in multidrug resistance (MDR) and resistance to key antimicrobials were analyzed.

Results:

Of the 200 isolates, Salmonella Typhi constituted 67% (n = 134), S. Paratyphi 18% (n = 36), and non-typhoidal Salmonella (NTS) 15% (n = 30). MDR among S. Typhi isolates declined from 35% in 2014 to 12% in 2023. In contrast, ciprofloxacin resistance showed a steady rise from 18% to 44% over the study period. Resistance to ceftriaxone and azithromycin remained consistently low (<5%). NTS isolates demonstrated heterogeneous resistance patterns, with sporadic emergence of cephalosporin resistance (2%).

Conclusion:

Over a decade, a notable reduction in MDR among typhoidal Salmonella was observed, alongside a concerning increase in fluoroquinolone resistance. Third-generation cephalosporins and azithromycin continue to be reliable therapeutic options.

Recommendations:

Regular institutional antibiogram updates, judicious use of fluoroquinolones, strengthening antimicrobial stewardship programs, and sustained laboratory-based surveillance are essential to guide empirical therapy and curb the progression of resistance.

Author Biographies

Dr. Anand Acharya, Dean and Professor, Department of Pharmacology, Konaseema Institute of Medical Sciences, Amalapuram, Andhra Pradesh, India

MBBS, MD (Pharmacology), currently serves as Dean and Professor, Department of Pharmacology, at the Konaseema Institute of Medical Sciences & Research Foundation (KIMS&RF), Amalapuram, Andhra Pradesh, India. A distinguished academician, researcher, and medical education leader, he has been pivotal in transforming KIMS&RF from its formative phase into a premier medical institution with over 200 undergraduate and 100 postgraduate seats.

With more than 18 years of teaching and administrative experience, Dr. Acharya has held several leadership positions, including Vice Principal, Principal, Chief Warden, Member Secretary of Institutional Ethics and Animal Ethics Committees, and is an approved PhD Guide under Dr. NTR University of Health Sciences, Vijayawada. His visionary leadership has significantly enhanced the institution’s academic quality, clinical exposure, research infrastructure, and postgraduate training standards.

He has successfully completed prestigious national faculty development programs such as the Revised Basic Course Workshop (rBCW), Advanced Course in Medical Education (ACME), and National Teacher Training Course (NTTC, JIPMER, Puducherry). He also serves as Coordinator for Pharmacovigilance and Materiovigilance Programs under IPC–PvPI and MoHFW, Government of India, contributing actively to national drug safety and regulatory initiatives.

A prolific academician, Dr. Acharya has authored and co-authored more than 100 scientific publications in reputed national and international indexed journals. His wide-ranging research covers toxicology, pharmacovigilance, antimicrobial resistance, endocrinology, neuropharmacology, and clinical pharmacology. His recent studies include long-term analyses of pyrethroid, paraquat, and chlorpyrifos poisoning, investigations into antimicrobial resistance trends, and predictive models for treatment outcomes in dermatological and toxicological emergencies.

Dr. Acharya’s professional interests include clinical pharmacology, toxicovigilance, rational drug use, pharmacovigilance systems, and innovations in medical education technologies. He continues to mentor numerous postgraduate and undergraduate researchers while playing an integral role in curriculum reform, ethics governance, and institutional academic advancement.ORCID iD: https://orcid.org/0009-0000-7967-9092

Dr. Nageswara Rao T, Associate Professor, Department of Pharmacology, Konaseema Institute of Medical Sciences and Research Foundation, Amalapuram, Andhra Pradesh, India

is currently serving as an Associate Professor of Pharmacology at Konaseema Institute of Medical Sciences and Research Foundation, Amalapuram, East Godavari District, Andhra Pradesh, India. He holds a doctoral degree in Medical Pharmacology from the prestigious Index Medical College and Research Institute, Madhya Pradesh. With over 16 years of teaching experience in various medical institutions, Dr. Nageswararao has made significant contributions to the field of pharmacology. His academic work includes nine research publications in reputed national and international journals, including one article indexed in PubMed. His dedication to research and education continues to enrich the academic and clinical landscape of medical pharmacology.T.Nageswararao:https://orcid.org/0009-0005-1638-6897

Dr. Bhavika.D, Associate Professor, Department of Pharmacology, Government Medical College and General Hospital, Quthbullapur, Telangana, India

MBBS, MD (Pharmacology), is currently serving as Associate Professor in the Department of Pharmacology, Government Medical College Quthbullapur. She worked as Assistant Professor at SVS Medical College, Mahbubnagar for a period of 1 year, She also worked as Assistant Professor at Kamineni Academy of Medical Sciences & Research centre for a period of 3 years then she joined as Assistant Professor at Government Medical College Nalgonda and served there for 5 years after which she was promoted to Associate Professor at Government Medical College Quthbullapur. She has guided Undergraduate and Postgraduate students in research work and thesis work. She has a teaching experience of 11 years and has authored 11 publications in reputed journals focusing on Pharmacology. ORCID iD: https://orcid.org/0000-0001-8921-1557

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