Rapid Serologic and Molecular Diagnosis of Scrub Typhus among Suspected Febrile Patients Visiting Mymensingh Medical College Hospital

Scrub typhus, caused by the bacterium- Orientia tsutsugamushi is one of the leading causes of undifferentiated treatable febrile illness in Asia pacific region. It is grossly under diagnosed in many tropical countries of South Asia including Bangladesh, due to wide range of non-specific clinical presentations, low index of suspicion among clinicians, limited awareness and lack of accurate diagnostic facilities. This cross-sectional descriptive study was conducted at Department of Microbiology, Mymensingh Medical College to diagnose scrub typhus by rapid Immunochromatographic test (ICT) as well as molecular detection of O. tsutsugamushi by Nested PCR and automated nucleotide sequencing among suspected febrile patients in Mymensingh, Bangladesh during 2019-20. Blood samples were collected from 402 febrile patients of suspected Rickettsial illness, referred from inpatient and outpatient departments of Medicine and Pediatrics, Mymensingh Medical College Hospital (MMCH). Among the enrolled 402 patients, 89 samples (22.13%) were seropositive by Immunochromatographic test (ICT) and 65 samples (16.16%) were positive for O. tsutsugamushi DNA by Nested PCR, targeting 47KDa gene. Therefore, 113/402 (28.10%) samples were positive for scrub typhus by PCR and/ or ICT. Highest number of patients was detected positive by nested PCR during the first 5-10 days of fever but only 2 cases were positive after 20 days. In case of ICT, highest positivity for only IgM (8.13%) and both antibodies (2.43%) were documented in first 5-10 days of fever, but IgG positivity was highest (41.66) in >20 days of fever. From 65 PCR positive samples, automated nucleotide sequencing was performed on 20 randomly selected samples and all were genetically confirmed to be O. tsutsugamushi.

Prevalence of ESBL Encoding Genes in Acinetobacter baumannii Strains Isolated from Various Samples of a Tertiary Care Hospital in Mymensingh

The aim of this study was to find the prevalence of ESBL genes among A. baumannii isolates. In this cross sectional study, 49 Acinetobacter spp. were isolated from various clinical samples from March 2019 to February 2020 conducted in the department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. Clinical samples including endotracheal aspirates, wound swab/pus, urine and blood. A total of 380 samples were analyzed. Growth was obtained in 34.21% of the samples yielding 130 organisms. Out of 130 organisms, 49(37.69%) were Acinetobacter spp. Among 49 Acinetobacter spp, 39(79.59%) were Acinetobacter baumannii which was identified by PCR targeting OXA-51 like gene. Amplification of the ESBL encoding genes, namely CTX-M, TEM, SHV done by molecular technique PCR. The most antibacterial resistance was against ceftriaxone (79.48%) and lower resistance only showed in colistin (12.82%). All the isolates were sensitive to tigecycline. The distribution of ESBLs genes such as TEM 20(51.28%), CTX-M 16(41.02%) and SHV 0(0%). The high resistance to most of the antibiotics among the studied strains and also a high prevalence of TEM gene in A. baumannii strains found in our study gives alarming sign towards the treatment complexity of these strains.

Detection of Antimicrobial Resistance Pattern and ESBL Production among Clinical Isolates of Salmonella Species in Mymensingh, Bangladesh

The occurrence of antimicrobial resistance in Salmonella enterica serovars (both typhoidal and non-typhoidal Salmonellae) is a major public health problem especially in developing countries, which have been associated with treatment failures. Therefore, the study was undertaken to determine the current antimicrobial resistance pattern and extended spectrum β-lactamase (ESBL) production among clinical isolates of Salmonella spp. during 2019-2020 in Mymensingh, Bangladesh. In this cross sectional study, 36 Salmonella enterica isolates were obtained from blood and stool culture of suspected 200 enteric fever and 100 gastroenteritis patients attending at Mymensingh Medical College Hospital, Mymensingh, Bangladesh. Isolated Salmonella species were identified by biochemical tests and Polymerase Chain Reaction (PCR). Disk diffusion test was performed by modified Kirby Bauer method. Minimum Inhibitory Concentration (MIC) of ceftriaxone was detected by agar dilution method. Double disk synergy test was used as a screening test for ESBL production. PCR was done for detection of blaTEM, blaSHV and blaCTX-MU genes. The isolates showed 25% resistance to Ceftriaxone and 58.3% to Azithromycin. The highest sensitivity rates were 88.9% to Meropenem and 83.3% to Amikacin. Whereas 6(16.7%) isolates were Multi Drug Resistant (MDR). Eight (8) isolates were confirmed as ESBL producer by DDST. The marked increase in MIC was observed between 8->512μg/ml to ceftriaxone. blaTEM, blaSHV and blaCTX-MU genes were detected in 3, 5 and 8 isolates respectively. In conclusion, the current study observed, higher level of resistance to ceftriaxone and azithromycin. At the same times 22.2% isolates showed ESBL production, which is a cause for concern as it may lead to treatment failure. On the other hand the study also showed the re-emergence of chloramphenicol and Sulfamethoxazole-Trimethoprim sensitivity.