Molecular markers for the detection of pathogenic and food poisoning potential of methicillin resistant Staphylococcus aureus isolated from wounds of hospitalized patients.

Pathogenic strains of Staphylococcus aureus are mostly resistant to methicillin and they can cause severe infections. The current study was planned to assess the food poisoning potential of pathogenic, methicillin resistant Staphylococcus aureus by molecular detection of enterotoxin A (Eta) gene. A total of 100 septic wound samples from patients admitted in surgical ward (n=50) and burn unit (n=50) of Mayo Hospital Lahore were collected aseptically. These samples were processed primarily for bacterial growth on nutrient agar and purified on mannitol salt agar where twenty (20) samples showed pin-point colonies with yellow discoloration of media. Moreover, isolates were further characterized on the basis of microscopic appearance and biochemical assays where fourteen (14) isolates were declared Staphylococcus. DNA of these isolates were subjected to 16S rRNA gene amplification and sequences of S. aureus were submitted to NCBI GenBank viz., MW344063.1, MW341438.1, MW344064.1, MW344065.1, MW341439.1, MW341440.1, MW345971.1, MW345972.1, MW345973.1, MW716458.1. All the isolates (n=10) demonstrated molecular confirmation of pathogenicity and methicillin resistance by amplification of Coa and mecA gene. Out of these ten isolates, three amplified enterotoxin A (Eta) gene were confirmed. It is concluded that enterotoxin A of S. aureus which causes food poisoning is present in pathogenic, methicillin resistant S. aureus isolated from various wounds infections.

Distribution and antibiotic sensitivity pattern of Mycobacterium tuberculosis isolates from children, enrolled in a tertiary care hospital.

The present study was planned to assess the distribution of tuberculosis in children and evaluate the antimycobacterial sensitivity pattern of Mycobacterium tuberculosis (MTB) isolates from pediatric patients. A total number of 1718 pediatric patients suspected of Mycobacterium tuberculosis were enrolled in the Institute of Child Health and Children's Hospital, Lahore during 2016-17. Out of 1718, only 710 different types of samples were tested for MTB. The samples were processed using bacteriology and GeneXpert along with the chest X-ray and clinical picture of the patients. The sensitivity pattern of Streptomycin, Isoniazid, Rifampicin and Ethambutol (SIRE) was determined using BACTEC MGIT 960. Total patients were divided into four groups including group A (birth to 12 months), B (1 to 5 years), C (6 to 10 years), and D (11 to 15 years). Out of 710, 106 (55 females and 51 males) were declared positive and 604 negative for tuberculosis. Out of 106 positive cases, 89 (83.96%) were sensitive to Rifampicin and 17 (16.04%) were resistant. Only, 04 (3.77%) were resistant to both Rifampicin and Isoniazid and declared as multidrug-resistant (MDR). It was concluded that children of age 11 to 15 years were more prone to MTB and a minimum percentage of MDR isolates was recorded in age group A (birth to 12 months).

Appraisal of anti-mycobacterial potential against MDR-MTB in pediatric patients, cytotoxicity and mutagenicity of Aloe vera and Allium sativum.

The purpose of the studies was to evaluate an in-vitro anti-mycobacterial activity of Aloe vera and Allium sativum against MDR-MTB, their cytotoxicity and mutagenicity. Four extracts of Aloe vera and Allium sativum were prepared by Soxhlet apparatus and their minimum inhibitory concentrations (MIC's) were determined by BACTEC MGIT960 system against multi drug resistant Mycobacterium tuberculosis (MDR-MTB) isolates, collected from pediatric patients. Fractions of Aloe vera and Allium sativum extracts were separated using glass column chromatography, followed by evaluation of cytotoxicity and mutagenicity by tetrazolium salt (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Ames test, respectively. Out of four extracts, ethanol extracts of Aloe vera and Allium sativum exhibited activity at MIC 5mg/mL to 7mg/mL and 3mg/mL to 5mg/mL, respectively and IC50 by MTT assay for combination of all fractions were 278.3mcg/100µL and 270.8mcg/100µL and in Ames assay M.I of TA98 were 0.14 and 0.07 and M.I of TA100 were 1.14 and 0.44, respectively. Aloe vera and Allium sativum extracts showed anti-mycobacterial activity against MDR-MTB isolates so, MIC of ethanol extracts of each plant and fractions of column chromatography had been checked. The MTT and Ames tests depicted that ethanol extracts of Aloe vera and Allium sativum were non-cytotoxic and non-mutagenic, and can be used in treatment of patients suffering from MDR-MTB.