Enteroaggregative Escherichia coli (EAEC) are a leading cause of diarrhea among children. The objective of this study was to define the frequency of EAEC among diarrheal children from flood-affected areas as well as sporadic cases, determine multidrug resistance, and evaluation of virulence using an in vivo model of pathogenesis. Stool samples were collected from 225 diarrheal children from 2010 to 2011 from flood-affected areas as well as from sporadic cases in Pakistan. Identified EAEC isolates were characterized by phylogrouping, antibiotic resistance patterns including the extended-spectrum beta lactamase spectrum, single nucleotide polymorphism detection in gyrA and parC, and virulence potential using wax worm, G. mellonella. A total of 35 (12.5%) confirmed EAEC isolates were identified among 225 E. coli isolates. EAEC isolates displayed high resistance to tetracycline, ampicillin, and cefaclor. A total of 34.28% were ESBL positive. Single nucleotide polymorphism detection revealed 37.14% and 68.57% isolates were positive for SNPs in gyrA (A660 -T660 ) and parC (C330 -T330 ), respectively. Phylogrouping revealed that B2 phylogroup was more prevalent among all EAEC isolates tested followed by D, A, B1, and non-typeable (NT). Infection of G. mellonella with EAEC showed that killing infective dose was 100% higher than E. coli DH5 alpha control. EAEC are prevalent among Pakistani children with diarrhea, they are highly resistant to antibiotics, and predominantly fall into B2 phylogroup. Epidemiologic surveillance of EAEC and other E. coli pathotypes is critical to assess not only the role of these pathogens in diarrheal disease but also to determine the extent of multidrug resistance among the population.

Objective: This study was aimed to compare the diagnostic accuracy of GeneXpert in smear negative as compared to smear positive pulmonary tuberculosis patients. Methods: This comparative cross sectional study was undertaken at Health Research Institute (National Institute of Health) TB Research Centre, Pulmonology King Edward Medical University Lahore, Pakistan. A total of 101 patients in each smear negative and positive groups were included. After taking the informed consent a predesigned questionnaire was used to collect the data. Results: A total of 202 patients consisting of 94 (46.5%) male and 108 (53.5%) females with mean age of patients as 39.83±18.14 years were included in this study. Highest proportion of 45% patients remained to be in age range of 18-35 years. Culture presented the highest accuracy of 96.1% with sensitivity, specificity and positive predictive value of 95.9%, 100%, and 100% respectively while GeneXpert remained to be 94.6%, 94.9%, 80%, and 99.5% respectively in this study. Conclusion: Accuracy of GeneXpert is excellent in diagnosis of smear positive pulmonary tuberculosis patients and very well in diagnosing smear negative pulmonary TB patients and a great addition in early and definite diagnosis of TB and keeps the ability to confirm around 75% smear negative pulmonary tuberculosis.