The antibiogram of pus cultures in federal tertiary care hospital, Islamabad and its utility in antimicrobial stewardship

Background and Objectives

Antimicrobial resistance has emerged as a significant global health threat. Infections caused by Multi Drug-Resistant (MDR) bacteria pose formidable challenges in terms of treatment options and patient outcomes. Pus cultures serve as crucial diagnostic tools in identifying the agents responsible for various infections, and their antimicrobial susceptibility patterns which help in establishment of empirical therapy guidelines. This study was conducted to determine the pathogen and its susceptibility pattern from pus cultures and to generate antibiogram in our tertiary care setting.

Materials and Methods

It was a cross-sectional study, conducted for a period of six months, from July 2022 to December 2022, in the Pathology Department of Pakistan Institute of Medical Sciences (PIMS).

Results

Out of total 2507 samples received, 1242 (49.5%) showed positive culture. Among the 1242 positive samples, 364 were Gram positive cocci (GPCs) and 878 were Gram negative rods (GNRs). Methicillin resistant Staphylococcus aureus (MRSA) was the most common isolate (23%) followed by Klebsiella pneumoniae (22.6%), Pseudomonas aeruginosa (16.9%), Enterobacter spp. (15.5%) and Escherichia coli (14.2%). Vancomycin was found to be highly effective (100%) against MRSA. GPCs were highly susceptible to linezolid (98%) while GNRs showed high level of sensitivity to colistin (96%) and tigecycline (92%).

Conclusion

The generation of a local antibiogram specific to the hospital setting is essential to effectively manage infections empirically and preserve the efficacy of existing antibiotics. By implementing antimicrobial stewardship practices based on a better understanding of antibiotic susceptibility patterns, we can contribute to the mitigation of antibiotic resistance and improve patient outcomes.

Novel Para-Aminobenzoic Acid Analogs and Their Potential Therapeutic Applications

A "building block" is a key component that plays a substantial and critical function in the pharmaceutical research and development industry. Given its structural versatility and ability to undergo substitutions at both the amino and carboxyl groups, para-aminobenzoic acid (PABA) is a commonly used building block in pharmaceuticals. Therefore, it is great for the development of a wide range of novel molecules with potential medical applications. Anticancer, anti-Alzheimer's, antibacterial, antiviral, antioxidant, and anti-inflammatory properties have been observed in PABA compounds, suggesting their potential as therapeutic agents in future clinical trials. PABA-based therapeutic chemicals as molecular targets and their usage in biological processes are the primary focus of this review study. PABA's unique features make it a strong candidate for inclusion in a massive chemical database of molecules having drug-like effects. Based on the current literature, further investigation is needed to evaluate the safety and efficacy of PABA derivatives in clinical investigations and better understand the specific mechanism of action revealed by these compounds.

Synthesis, crystal structure, spectroscopic and computational investigations of the newly synthesized Schiff bases scaffold as enzyme inhibitor

The current project was planned to access the enzyme inhibition potential of the synthesize imines; (E)-2-(2-hydroxy-4,5-dimethoxybenzylideneamino)benzonitrile 1 and (E)-2-(((3-hydroxy-4-methylphenyl)imino)methyl)-4-methoxyphenol 2 by the reported protocol of our continuous research and also assess their theoretical function in term of in silico action. The structural characterization of imines was done through advanced techniques i.e., FTIR, ¹H NMR, ¹³C NMR, and UV spectroscopy. Moreover, a single X-Ray diffraction technique (SCXRD) was employed for real structural identification of imines dimensions, which revealed that compound 1 has a triclinic crystal system although 2 has a monoclinic one. A 2D fingerprint plot and Hirshfeld surface analysis (HS) was employed in the crystalline assembly of compounds to check intermolecular contacts and also their degree of contributions. Both compounds were optimized by B3LYP functional mode using a certain basis set (6-31G). The practical data (XRD) and theoretical data (DFT) of both molecules were compared and found between a sound coherence. Molecular docking studies in term of in silico assessment were conducted against enzymes of the esterase and alpha-glucosidase family. The docking outputs give a forecast about compounds that could be employed as protein inhibitors against analyzed protein surfaces.

Computational modeling of imines based anti-oxidant and anti-esterases compounds: Synthesis, single crystal and In-vitro assessment

Molecular modeling strategy was adopted to check the biological potential of the imine based molecules against free radical, acetylcholine esterase and butyrylcholine esterase. Three Schiff based compounds as (E)-2-(((4-bromophenyl)imino)methyl)-4-methylphenol (1), (E)-2-(((3-fluorophenyl)imino)methyl)-4-methylphenol (2) and (2E,2E)-2-(2-(2-hydroxy-5-methylbenzylidene)hydrazono)-1,2-diphenylethanone (3) were synthesized with high yield. The synthesized compounds were characterized with the help of modern techniques such as UV, FTIR and NMR while exact structure was depicted with Single Crystal X-Ray diffraction technique which disclosed that compound 1 is orthorhombic, while 2 and 3 are monoclinic. A hybrid functional (B3LYP) method with general basis set of 6-31 G(d,p) were applied to optimize synthesized Schiff bases. The contribution of in-between molecular contacts within a crystalline assembly of compounds were studied using Hirshfeld surface analysis (HS). In order to check the ability of the synthesized compounds toward free radical and enzyme inhibition, in vitro models were used to assess the radical scavenging and enzyme inhibition potential which depicted that compound 3 showed highest potential (57.43 ± 1.0%; DPPH, 75.09 ± 1.0%; AChE and 64.47 ± 1.0%; BChE). The ADMET assessments suggested the drug like properties of the synthesized compounds. It was concluded from results (in vitro and in silico) that synthesized compound have ability to cure the disorder related to free radical and enzyme inhibition. Compound 3 was shown to be the most active compared to other compounds.

Reviving the role of mecillinam against extended spectrum beta-lactamase producing enterobacterales

Background and Objectives: This study was designed to determine the in vitro efficacy of mecillinam against extended spectrum beta lactamse producing Enterobacterales. Materials and Methods: After proper permission from Ethical Review Committee of the Institute, all samples yielding growth of ESBL producingEnterobacterales were part of the study and were processed according to routine microbiological procedures. Routine antibiotic sensitivity testing was done onMuller Hinton Agar by Modified Kirby Bauer Method. All Gram negative isolates were subjected to concomitant detection of ESBL production by doubledisc synergy method. All ESBL producers were then subjected to the mecillinam Minimum Inhibitory Concentration (MIC) determination by E test. The results were interpreted as per CLSI Guidelines. Results: A total of 120 ESBL producing Enterobacterales isolates were included in the study. The mean age of patients with ESBL infection was 45 ± 18.7years. There were 44% male and 55% female patients. Majority of the ESBL producing Enterobacterales were isolated from urine samples (56%), followed bypus. Among the isolated organisms, Escherichia coli (45%) was the most frequently isolated organism followed by Klebsiella spp. (22%). Overall 83% of theisolates turned out to be sensitive to mecillinam. MIC50 of mecillinam against ESBL producing Gram negative rods (GNR) turned out to be 1 ug/ml and MIC90 turned out to be 2 ug/ml. Conclusion: Mecillinam shows good in vitro efficacy against ESBL producing Enterobacterales in our study. Further studies with more sample size and from diverse areas across the country should be done to evaluate its efficacy.  

Designing of Thiazolidinones for COVID‐19 and its Allied Diseases: An In silico Evaluation

In silico studies in terms of density functional theory (DFT), molecular docking, and ADMET (absorption, distribution, metabolism, excretion and toxicity) were performed for 55 thiazolidinones compounds derived from different amines and aldehydes. DFT is a computational quantum mechanical modeling method used to predict the various properties of the compounds. Different parameters such as Electronegativity (x), Chemical Hardness (ŋ), Chemical Potential (μ), Ionization potential (IP), and Electron Affinity (EA), etc. were calculated by Koopmans theorem. The compounds were docked with Molecular Operating Environment (MOE) software using already reported PDB files of BChE, AChE, and α‐glucosidase. To analyze the Spike Glycoprotein of SARS‐Cov‐2 and heterocyclic compounds, molecular interactions study was carried out between Spike Glycoprotein of SARS‐Cov‐2 (6VXX) and 55 synthetic heterocyclic compounds. It was performed by the utilization of PyRx Virtual Screening Tool and AutoDock Vina based virtual environment was used in PyRx. Maximum binding affinity was observed with compound A7 which was −8.7 kcal/mol and then with A5 which was −8.5 respectively. In the case of the AChE enzyme, B5 has a maximum docking score of −12.9027 kcal/mol while C7 depicted the maximum score for the BChE enzyme with a value of −8.6971 kcal/mol. The docking studies revealed that C6 compound has maximum binding capacity toward glucosidase (−14.8735 kcal/mol). ADMET properties of under consideration compounds were determined by Swiss online‐based software which concluded that these molecules have a drug‐like properties and having no violation.

Surfactant stabilized gold nanomaterials for environmental sensing applications - A review

Surfactant stabilized Gold (Au) nanomaterials (NMs) have been documented extensively in recent years for numerous sensing applications in the academic literature. Despite the crucial role these surfactants play in the sensing applications, the comprehensive reviews that highlights the fundamentals associated with these assemblies and impact of these surfactants on the properties and sensing mechanisms are still quite scare. This review is an attempt in organizing the vast literature associated with this domain by providing critical insights into the fundamentals, preparation methodologies and sensing mechanisms of these surfactant stabilized Au NMs. For the simplification, the surfactants are divided into the typical and advanced surfactants and the Au NMs are classified into Au nanoparticles (NPs) and Au nanoclusters (NCs) depending upon the complexity in structure and size of the NMs respectively. The preparative methodologies are also elaborated for enhancing the understanding of the readers regarding such assemblies. The case studies regarding surfactant stabilized Au NMs were further divided into colorimetric sensors, surface plasmonic resonance (SPR) based sensors, luminescence-based sensors, and electrochemical/electrical sensors depending upon the property utilized by the sensor for the sensing of an analyte. Future perspectives are also discussed in detail for the researchers looking for further progress in that particular research domain.

Therapeutical Potential of Imines; Synthesis, Single Crystal Structure, Computational, Molecular Modeling, and ADMET Evaluation

Imines are multipurpose pharmacophores, simply accessible compounds, and have a broad range of usage in several areas of chemistry especially in medicine. Two novel compound imines, (E)-4-methyl-2-((o-tolylimino)methyl)phenol (1) and (E)-2-(((4-methoxybenzyl)imino)methyl)-4-methylphenol (2), were synthesized with effective product via reported protocol in the literature. Single crystal X-ray diffraction (SCXRD) was employed for structural exposition, disclosing that both compounds are orthorhombic. To optimize the newly designed imines, a B3LYP functional with a basis set 6-31G(d,p) was mainly considered. DFT results were utilized to check correlation between the data recovered from SCXRD outcomes and also to measure the energy difference. Hirshfeld surface study was done to demonstrate the intermolecular contacts along the percentage of interaction in the overall crystalline compound. Molecular operating environment program was tested against AChE and BChE enzymes to perform a modeling study of the compounds. The docking score and binding affinity of the compounds revealed that 2 showed comparatively more inhibition than 1. In silico ADMET studies exposed the physiochemical nature of these novel compounds, and it also unveiled that both compounds behaved as drug-like candidates.

Heterocyclic compounds as a magic bullet for diabetes mellitus: a review

Diabetes mellitus (DM) is a major metabolic disorder due to hyperglycemia, which is increasing all over the world. From the last two decades, the use of synthetic agents has risen due to their major involvement in curing of chronic diseases including DM. The core skeleton of drugs has been studied such as thiazolidinone, azole, chalcone, pyrrole and pyrimidine along with their derivatives. Diabetics assays have been performed in consideration of different enzymes such as α-glycosidase, α-amylase, and α-galactosidase against acarbose standard drug. The studied moieties were depicted in both models: in vivo as well as in vitro. Molecular docking of the studied compounds as antidiabetic molecules was performed with the help of Auto Dock and molecular operating environment (MOE) software. Amino acid residues Asp349, Arg312, Arg439, Asn241, Val303, Glu304, Phe158, His103, Lys422 and Thr207 that are present on the active sites of diabetic related enzymes showed interactions with ligand molecules. In this review data were organized for the synthesis of heterocyclic compounds through various routes along with their antidiabetic potential, and further studies such as pharmacokinetic and toxicology studies should be executed before going for clinical trials.

Diabetes mellitus (DM) is a major metabolic disorder due to hyperglycemia, which is increasing all over the world.

Endogenous methicillin resistant staphylococcus aureus as a source of post-operative surgical site infections

OBJECTIVE

To determine frequency of Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) in pre-operative patients and its frequency in Surgical Site Infections (SSIs) post operatively.

METHODS

It was a descriptive cross sectional conducted at Department of Microbiology, Fauji Foundation Hospital Rawalpindi (FFH), Pakistan. Samples were collected from 1st November-31st May 2018. Total 75 samples were collected during the period. Consecutive non-probability sampling technique was utilized. Specimens were collected from nose, axilla and groin of preoperative patients. Methicillin Resistant Staphylococcus aureus was identified if only isolated from these sites. Patients were followed till his/her discharge from the hospital and if they developed infection post operatively, pus specimen from infected site was also collected and identified.

RESULTS

Out of 75 specimen preoperatively, 11(14.7%) were identified as endogenous MRSA. From these, 33(44%) developed Surgical site infections (SSIs), among them 19(57%) were MRSA (09 endogenous, 10 exogenous), 7(21.2%) were Escherichia coli, 3(9.1%) were Klebsiella pneumoniae, 3(9.1%) were Enterococcus faecalis and 1(3%) was Methicillin Sensitive Staphylococcus aureus.

CONCLUSIONS

The results of this study determined that Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) could be isolated from patients going for surgery if microbiological screening was done at the time of admission. This could prevent patients from Surgical Site Infection Post operatively by these endogenous MRSA. This search and wipe out strategy is able to curtail the events of outbreak, reduce hospital stay and decrease budget of the hospital by providing guidance in choice of empirical therapy for infection.

Comparison of 99mTc Injected Activity with Prescribed Activity in Four Types of Nuclear Medicine Exams

BACKGROUND

99mTc is a radioactive isotope that is obtained by eluting a 99Mo/99mTc generator. (PINSTECH, Islamabad) and used for radionuclide scanning.

OBJECTIVES

The objective of this work is to study the uncertainties in 99mTc activity that exist due to time delay between injection preparation and administration to patients, during the process of gamma camera scanning.

METHODS

Lead canisters were used for storing elution vials and dose calibrator for measuring 99mTc activity in mCi. The activity of preparing 99mTc injection and its administration to patients were compared with the prescribed values of activity recommended in the Society of Nuclear Medicine procedure guidelines.

RESULTS

This study showed that uncertainty in the activity existed in one thyroid patient, 38 bone patients, 5 renal patients and 45 cardiac patients.

CONCLUSION

This uncertainty in activity exists due to time delay between injection preparation and administration to patients, as well as due to residual radionuclide that is not injected into patients and remains in the syringe.

The metabolic syndrome and inflammation: role of insulin resistance and increased adiposity

OBJECTIVES

We sought to determine the role of obesity and insulin resistance (IR) in the pathogenesis of inflammation in metabolic syndrome (MetS).

METHODS

Our study included 100 patients with MetS and 100 age and gender matched control patients who attended a tertiary care laboratory in Rawalpindi, Pakistan. Anthropometric data was obtained including height and weight to calculate body mass index. A record of patient's blood pressure (BP), waist circumference (WC) and hip circumference (HC) was made. Biochemical analysis included measurements of fasting glucose, triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), insulin, and high-sensitivity C reactive protein (hsCRP). IR was determined by the homeostasis mode assessment insulin resistance (HOMA-IR) method.

RESULTS

The levels of hs-CRP were found to be elevated in all patients with MetS where it correlated significantly with all its components including measures of obesity, fasting insulin and glucose levels, IR, TG and HDL-c. However, on linear regression analysis only WC, fasting insulin, and HOMA-IR remained significantly correlated with hs-CRP.

CONCLUSION

MetS is a condition characterized by chronic low-grade inflammation, which arises because of increased abdominal adiposity and IR. Large multicenter studies are needed to gain insight into its pathogenesis and derive treatment strategies.

Modified Hodge test: A simple and effective test for detection of carbapenemase production

BACKGROUND AND OBJECTIVES

Resistance among bacterial isolates is the leading cause of increased mortality and morbidity worldwide. Carbapenems once thought to be effective are becoming ineffective mostly due to the emergence of carbapenemase. This study was designed to determine in vitro efficacy of Modified Hodge test for detection of carbapenemase production in Gram negative rods.

MATERIAL AND METHODS

The study was done in the Department of Microbiology, Armed Forces Institute of Pathology Rawalpindi Pakistan from January 2010 to December 2010. A total of 200 Gram negative rods from different clinical samples were taken. Those isolates which showed intermediate or susceptible zones i.e 16mm-21mm on disc diffusion were included in the study. These isolates were then subjected to Modified Hodge test.

RESULT

Out of 200 isolates, 138 (69%) were positive for carbapenemase production by Modified Hodge test. Out of 138 MHT positive organisms, the frequency of E. coli was 38%, followed by Pseudomonas aeruginosa (30%), Klebsiella pneumoniae (17%), Acinetobacter baumannii (12%), Citrobacter diversus (2%) and Enterobacter agglomerans (1.4%).

CONCLUSION

Modified Hodge test is a simple test which can be performed in the routine lab for detection of carbapenemases in isolates showing intermediate or sensitive zone diameter on disc diffusion.

Non-dermatophyte moulds as pathogens of onychomycosis

OBJECTIVE

To determine the role and pattern of non-dermatophyte moulds as causative agents of onychomycosis.

STUDY DESIGN

Case series.

PLACE AND DURATION OF STUDY

Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from November 2009 to July 2010.

METHODOLOGY

Nail clippings and nail scrapings were obtained from abnormal looking nails with treatment and detection failure for onychomycosis. Microscopic (40% potassium hydroxide mounts) examination and culture on Sabouraud's dextrose agar (SDA), SDA containing chloramphenicol, and SDA containing actidione and chloramphenicol were used for species identification.

RESULTS

Non-dermatophyte moulds were isolated from 32 out of the total 47 culture positive cases (68%). Alternaria alternata was the commonest species (46%). Dermatophytes were isolated from only 7 patients (15%) belonging to genus Trichophyton. Yeasts were isolated in 8 (17%). There was no fungal growth in 53% of cases.

CONCLUSION

The non-dermatophytes should be considered important in evaluating the culture negative cases for dermatophytes as well as those cases ending up in treatment failure after empirical treatment for dermatophyte infections.

Ambu bag as a source of Acinetobacter baumannii outbreak in an intensive care unit

This case report describes an outbreak of multidrug resistant Acinetobacter baumannii in the intensive care unit of a tertiary care hospital. Three patients were infected on the same day from an Ambu bag which was used on all the patients. The outbreak was immediately identified and the source was traced within one week. Appropriate measures were taken and a continuous surveillance was carried out resulting in reporting of no such case from the intensive care unit in the last 6 months.