Anitmicrobial Susceptibility to Microoranisms in Hematological Malignancies; A Need to Review Institutional Protocols
Authors: Anwar Nida , Fatima Naveena , Jamal Aisha , Rizvi Qurat-Ul-Ain , Shamsi Tahir 
Published: November 2023

Abstract

Introduction
Febrile neutropenia is a medical emergency in patients with hematological malignancies. The severity of neutropenia and the duration of infection have an important implication on primary treatment outcome. Previously assessed institutional review revealed gram negative bacteria to be the most common microorganisms, and leading cause of febrile neutropenia. However, the predominance of gram positive bacteria had also increased in later past years [1]. In high risk patients, infections caused by multidrug resistant bacteria worsen treatment complications and thus at times empirical use of antibiotics like colomycin is required; otherwise the prognosis may be jeopardized [2]. Regular surveillance of local flora and susceptibility pattern of antimicrobial is must to elude the antimicrobial resistance.

Objective
The study was conducted to evaluate the prevalence of microorganisms and to observe the sensitivity pattern of antimicrobials as an institutional protocol to establish antimicrobial policies.

Material and methods
A cross sectional study was conducted at National Institute of blood diseases and bone marrow transplantation, PECHS campus from August 2021 - January 2022. Ethical approval was taken from research committee prior to the study and informed consent was taken from the patients. Febrile neutropenia was defined as a single reading of oral temperature of ≥38 °C on two or more occasions in 12 h in the presence of absolute neutrophil count of less than 1000cells/mm. Blood cultures were performed using the BACTEC blood culture system. Organisms were identified according to routine bacteriological procedures and disc diffusion method was used for interpreting antibiotic susceptibility. Data was analyzed by SPSS version 23.0. Frequencies and percentages were calculated for categorical variable and mean (standard deviation) was computed for quantitative variables. Association between categorical variables was observed using the chi-square test or Fisher’s exact test. P value of &lt;0.05 was considered statistically significant.

Results
A total of 310 cultures taken from blood (37.4%), peripheral line (4.2%), hickman line (8.1%), red line (2.6%), pus (7.1%), sputum (9.7%) and urine (31%) samples were observed. Out of total 213 (69%) were found to be gram negative and 97 (31%) were gram positive. Gram negative were mostly reported in blood cultures 61 (20%) while gram positive was found in urine cultures 80 (26%). E.coli (40.8%) was the most prevalent among the gram negative microorganisms followed Klebsiella pneumonae (16.9%), Pseudomonas species (11.7%), Pseudomonas aeruginosa (11.3%), Burkholderia cepacia (7%), Enterobacter species (3.3%), Moraxella species (3.3%), Proteus mirabilis (2.8%), Salmonella typhi (1.4%), Acinetobacter species (0.9%) and Citrobacter species (0.5%). In gram negative organisms, Acinetobacter species, Burkholderia cepacia, Citrobacter species and Moraxella species were identified substantially which were not previously prevalent. In gram positive microorganisms Staphylococcus epidermidis (55.3%) was more prevalent, followed by Enterococcus species (19%), Micrococcus species (16%), Streptococcus species (6%), Staphylococcus aureus (3.7%), from which Micrococcus species was reported for first time. Sensitivity of meropenem, amikacin and colistin was higher in gram negative while the sensitivity of fosfomycin, and linezolid was found in gram positive isolates The association of sensitivity and resistance with gram negative and positive isolates was found statistically significant with amikacin, vancomycin, fosfomycin and ciprofloxacin (p=&lt;0.05).

Conclusion
Gram negative isolates were found prevalent in our study. The sensitivity of meropenem, amikacin and colistin was high than other regimens in gram negative while the sensitivity of fosfomycin, and linezolid was found in gram positive isolates. Few emerging isolates were observed in the study as well. The regular review of microbial pattern and susceptibility evaluation is imminent for prevention of microbial resistance and assessment of institutional practices.

References
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2. Kanadan A, Bhagwath AA, Sebastian BT, Rudrapathy P, Manickam S. Study on oral microbial flora and antibiotic sensitivity pattern among oral cancer patients in a tertiary cancer care center. Journal of Orofacial Sciences. 2019 Jul 1;11(2):93.