Background Enteric fever is a serious public health problem in Pakistan. Growing problem of drug-resistant Salmonella strains and outbreak of ceftriaxone-resistant Salmonella typhi in Hyderabad during 2016-2017 is concerning. This study aimed to determine the antibiogram profile of Salmonella typhi and Salmonella paratyphi isolated from blood cultures of patients presenting in Pakistan Institute of Medical Sciences (PIMS), Islamabad. Materials and methods A retrospective cross-sectional study conducted in PIMS. A case of enteric fever was defined as a patient with blood culture positive for either S. typhi or S. paratyphi. Demographics and antibiogram profile of the 664 cases who presented during 2012-2018 were included in this study. Results Out of 664 cases, S. typhi was isolated from 528 and S. paratyphi was isolated from 136 cases. Males accounted for the majority of the cases (n = 440, 66.3%). Clustering of the cases was observed in young adults (18-25 years). Incidence was highest during months of summer and monsoon (May-September). Most of the S. typhi isolates were resistant to the first-line antibiotics (amoxicillin 57.6%, co-trimoxazole 61.4%, chloramphenicol 46.9%) and ciprofloxacin (62.7%). Antibiotic resistance rates were lowest for imipenem (3.8%) and ceftriaxone (4.4%). Among S. typhi isolates tested for all first-line antibiotics, 44.6% (149/334) were multidrug-resistant (MDR). In contrast, only 12.2% (11/90) of the S. paratyphi isolates were MDR. 0.7% (2/283) of the tested S. typhi isolates were extensively drug-resistant (XDR). XDR strains were sensitive to imipenem. There was an overall reduction in first-line antibiotic resistance rates from 2012 to 2018.

Background Tuberculosis (TB) is a major health problem. In Pakistan, the diagnosis of pulmonary tuberculosis mainly relies on acid-fast bacilli (AFB) smear microscopy and Xpert® MTB/RIF assay (Cepheid Inc., Sunnyvale, CA) - a nucleic acid amplification test - where available. There is a wide variation in the reported sensitivity of Ziehl-Neelsen (ZN) smear microscopy across previous studies. This study aimed to determine the accuracy of sputum ZN smear microscopy in diagnosing pulmonary tuberculosis as compared with the sputum GeneXpert (Xpert MTB/RIF assay) as the reference test. Materials and methods This is a retrospective cross-sectional study conducted in the outpatient department of the Pakistan Institute of Medical Sciences. This study included 326 patients, aged 12 years and above, who had their sputum samples tested for ZN smear microscopy and GeneXpert during the period January to June 2019. Patients' demographic details, sputum ZN smear microscopy, and GeneXpert test results were collected for data analysis. A case of pulmonary tuberculosis was defined as a patient with positive sputum GeneXpert test result. Results Out of the 326 patients, GeneXpert detected MTB deoxyribonucleic acid (DNA) in 50 patients and ZN smear microscopy detected AFB in 30 patients. There was a marginal male predominance among GeneXpert positive cases. Adolescents were the least affected age group. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of ZN smear microscopy were 60%, 100%, 100%, 93.24%, and 93.87%, respectively. The positive likelihood ratio was infinite whereas the negative likelihood ratio was 0.4. The area under curve (AUC) for ZN smear microscopy was 0.800 and receiver operating characteristic (ROC) curve analysis revealed a diagonal straight line closer to the left upper corner. Conclusion Sputum ZN smear microscopy is a highly specific but moderately sensitive test for the diagnosis of pulmonary tuberculosis. This study recommends the sputum GeneXpert MTB/RIF test to avoid a missed diagnosis of smear-negative pulmonary TB.

Aim:The present study was carried out to study the effect of ursolic acid (UA) as a potential anti-biofilm agent in dispersing the biofilm generated by Staphylococcus aureus isolated from milk samples of crossbred dairy cows on the day of drying. Further, in the S. aureus isolates, the presence of intracellular adherence gene locus involved in biofilm production (icaD) was investigated.Materials and Methods:A total of 50 S. aureus strains were isolated over a period of 3 months from 200 milk samples collected from crossbred dairy cows on the day of drying. These isolates were subjected for biofilm detection by Congo red agar (CRA), microtiter plate assay (MTP), and polymerase chain reaction specific for icaD gene. The antagonistic effect of biofilm formation by UA was studied using different concentrations (30 µg/ml and 60 µg/ml) of UA and compared with the control group.Results:Among the 50 S. aureus subjected for biofilm detection, 34 and 40 isolates were detected as biofilm agents by CRA and MTP methods, respectively. The in vitro studies on the effect of UA in inhibiting biofilm formation by S. aureus using MTP assay showed 71.5% and 48.6% inhibition at UA concentrations of 60 µg/ml and 30 µg/ml, respectively, with a significant difference (p<0.05) between the treated and untreated isolates, which was further evident by scanning electron microscopy. Interestingly, the isolates that were tested to be resistant through Antibiotic Sensitivity Test to commonly used antibiotics were found to be sensitive to all the tested antibiotics following UA treatment at both the tested concentrations. Furthermore, molecular detection of icaD gene for biofilm detection revealed that all the isolates that were positive by MTP had icaD gene.Conclusion:Increased incidence of biofilm agents in dairy infections must be considered as an alarming situation. UA treatment significantly enhanced the sensitivity of the microbial pathogens to commonly used antibiotics. Hence, attention must be paid toward implementation of new strategies such as therapeutic regimes with a combination of antibiotic and anti-biofilm agents for effective treatment of infections in dairy farms.