USE OF CARTRIDGE BASED NUCLEIC ACID AMPLIFICATION TEST FOR RAPID DETECTION OF MYCOBACTERIUM TUBERCULOSIS IN PULMONARY AND EXTRAPULMONARY TUBERCULOSIS

Objective: Tuberculosis is an airborne infection caused by Mycobacterium tuberculosis. Timely diagnosis and treatment are important to prevent the spread of infection. Cartridge-based nucleic acid amplification test (CBNAAT) provides a valuable tool in the early detection of TB. This study is undertaken to evaluate the utility of CBNAAT for the detection of MTB. Comparison of cartridge-based nucleic acid amplification testing with ZN staining. Methods: This prospective observational study was carried out in the Department of Microbiology, BLDEDU’s Shri B. M. Patil Medical College, Hospital and RC and Dr. Karigoudar Diagnostic Laboratory, Vijayapur. A total of 129 samples from patients with the presumptive diagnosis of TB based on history, clinical presentation, and radiological findings were included in the study. All samples were subjected to ZN staining, and Cartridge-based nucleic acid amplification test and data were analyzed. Results: The present study showed ZN smear positivity of 7.75% and CBNAAT positivity of 19.38%. CBNAAT sensitivity and specificity were 90% and 86.55, respectively, compared with ZN staining with a significant P value of <0.001. Conclusion: CBNAAT helps diagnose TB and detect rifampicin resistance within 2-3 h with high sensitivity and specificity. Rifampicin resistance detection is of great concern, which otherwise leads to treatment failure and on time spread of multidrug resistance TB, leading to increased morbidity and mortality

Detection of AmpC Beta-lactamases among Escherichia coli isolates at a tertiary care hospital in Karnataka

Background & objective: AmpC β-lactamases are clinically significant because they may confer resistance to a wide variety of β-lactam drugs, including α-methoxy-β-lactams, such as cefoxitin, narrow-, expanded- and broad-spectrum cephalosporins, β-lactam-β-lactamase inhibitor combinations and aztreonam. Although reported with increasing frequency the true occurrence in different organisms remains unknown. The present study was conducted to determine the occurrence of AmpC β-lactamases among the clinical isolates of Escherichia coli. Methods: A total of 100 non-repeat clinical isolates obtained from urine, pus, sputum, blood and body fluids were taken. All the isolates were screened for AmpC β-lactamases by standard disc diffusion breakpoint for cefoxitin (30µg). Isolates with zone diameter less than 18 mm were tested for AmpC activity by AmpC disc test. Results: Of the 100 isolates that were tested, 30 yielded cefoxitin zone diameters less than 18 mm (screen positive). Production of AmpC β-lactamase was detected in 24 isolates by AmpC disc test. Conclusion: AmpC disc test can be used as a simple, convenient and rapid screening test for detection of AmpC β lactamase in clinical laboratories

Bacteriological Profile of Catheter Associated Urinary Tract Infection and its Antimicrobial Susceptibility Pattern in a Tertiary Care Hospital

Introduction: Among nosocomial infections catheter associated urinary infection (CAUTI) is one of the most common infection. Uropathogens isolated from CAUTI are more multi-drug resistant than from community acquired urinary tract infection (UTI). Hence the aim of this study is to isolate uro-pathogens from CAUTI and find out antibiotic sensitivity pattern among the isolates. Material and Methods: This is a prospective and observational study conducted at tertiary care teaching hospital over a period of One year. Urine samples were collected from patients who were catheterized, according to CDC guidelines using sterile needle from tubing of catheter under aseptic precautions. The samples were processed in the Department of Microbiology, as per standard protocols. Uropathogens were isolated, identified and subjected to antibiotic sensitivity testing. Results: The present study shows the pathogens causing CAUTIs and their antibiotic susceptibility pattern. Of 200 urine samples cultured from patients with CAUTI 50 (25%) yielded growth of single organism and 150 (75%) showed no evidence of growth. Escherichia. coli 38% was the predominant pathogen followed by Klebsiella pneumoniae 30%, Pseudomonas aeruginosa 10% Staphylococcus aureus 6.0%. Conclusion: The result showed that the most predominant bacterial isolate causing CAUTI was E. coli. Overall, the percentage of sensitivity of Gram-negative bacteria to all antibiotics tested was relatively low, except for Amikacin, Meropenem and Imipenem which were relatively high. Gram positive cocci showed high susceptibility to Linezolid, Tigecycline and Vancomycin

Comparison of Active and Passive Methods of Air Sampling to Evaluate the Microbial Contamination of Air in Operation Theaters

The microbiological assessment of the air in operating theatres is critical to control hospital-acquired infections. Regular surveillance is an important tool to evaluate the quality of air and find areas requiring intervention. In this context, the present study is undertaken to assess and compare the microbial contamination levels in operation theatre by active and passive methods. All the environmental surfaces and equipment of OTs and ICU at tertiary care hospital in Vijayapur, included in the study. This study used three sampling procedures: active, passive methods for air sampling, and swabing method for surfaces and equipment. Out of 15 OTs air sampling, the passive method showed more bacterial air contamination than the active method. Statistically, a significant difference was observed with the passive method compared to the active method with p-value of 0.0336 for both bacteria and fungus growth assessment. Out of total 90 swabs collected from all the OTs surfaces and instruments, Pseudomonas species (40%), Bacillus species (40%), Klebsiella species (20%) were the common species isolated. From the 50 swabs collected from in ICUs surfaces and instruments, culture positivity was 16% for pathogenic bacteria; Pseudomonas aeruginosa (62%), Klebsiella pneumonia (25%), and Escherichia coli (13%). The present study showed that the passive method is a better monitoring tool than the active method. So we recommend using passive air sampling method compared to active method, which is easy, cheap, and no instrument is needed for sampling the air

Antibiogram of Gram Negative Bacteria Isolated from the Skin and Soft Tissue Infections a Guide for Empirical Therapy to the Clinicians

The antibiogram gives the periodic summary of antimicrobial susceptibilities of local bacterial isolates submitted to the hospitals microbiology laboratory. Antibiogram can be of great use in assessing the local susceptibility rates and can serve as a tool in designing the empirical antibiotic therapy and also in monitoring the resistance trends over time within in an institution. Pus samples from various clinical conditions like abscess, cellulitis, necrotizing fasciitis, wound infections; diabetic foot ulcers were included in the study. A total of 1124 positive cultures were obtained out of which 736 yielded various Gram negative organisms and 488 were Gram positive organisms. Only Gram negative organisms were considered in the study as gram negative organisms are common etiological agents of skin and soft tissue infections and pose a great challenge to the treating physician as they are known to develop a high antimicrobial resistance. The organisms isolated in our hospital were Pseudomonas aeruginosa (192), Klebsiella pneumonia (173), Escherichia coli (168), Citrobacter species (117), Acinetobacter species (47), and Proteus species (39). In our study which aims at formulating an empirical therapy for Gram negative organisms the drugs with highest sensitivity were Imipenem (51%), Amikacin (43%), Meropenem (38%), Tobramycin (36%), and Ciprofloxacin (34%) Gentamicin (34%), Netimicin (33%), Cotrimoxazole (32%), Piperacillin (28%),Tetracycline (28%), Ceftazidime (28%), Levofloxacin (26%), Ceftriaxone (26%), Colistin (22%), Carbenecillin (21%), Cefoperazone (21%), Cefoperazone +Sulbactum (21%), Azonetrem (21%), Cefipime (20%), Cefuroxime (17%), Cephaxlein (15%), Ampicillin (12%), Amoxyclav (10%). With the knowledge of most commonly isolated organisms causing SSTIs and their antimicrobial susceptibility patterns the clinicians can start the most likely antibiotic and can change accordingly once the sensitivity report is available

Comparative Analysis of Enzyme-Linked Immunosorbent Assay and Immunochromatography for Rotavirus and Adenovirus Detection in Children below Five Years with Acute Gastroenteritis

Introduction The most frequent etiologies of viral gastroenteritis among young children are rotavirus and enteric adenovirus. The clinical signs and symptoms of viral gastroenteritis are not distinct enough to allow for diagnosis. For the diagnosis and treatment of acute gastroenteritis, it is preferable to use quick, simple, and low-cost procedures. This study was undertaken to determine efficacy of immune-chromatography test (ICT) in comparison with enzyme-linked immunosorbent assay (ELISA) to detect rotavirus and adenovirus antigen in fecal specimen among children less than 5 years of age with acute gastroenteritis. Materials and Methods In a cross-sectional observational study, 314 fecal samples were collected from children aged less than 5 years with acute gastroenteritis attending or admitted to a tertiary care hospital during the 1 year study period. Samples were tested for rotavirus and adenovirus antigen using ICT and ELISA. Results Among the 314 children evaluated, 112 (35.66%) had rotavirus infection, nine (2.86%) had adenovirus infection, and three (0.95%) had both rotavirus and adenovirus infection. This study found that ICT is 98.20% sensitive and 100% specific for the diagnosis of rotaviral diarrhea and 100% sensitive and 99.7% specific for adenovirus diarrhea, compared to ELISA. Conclusion Immunochromatography tests used for the detection of rotavirus and adenovirus in the fecal sample showed a high degree of sensitivity and specificity. The ICT is easy to perform and rapid, and it does not require any special equipment. Hence, the ICT could be used as an alternative method for detecting viral pathogens in clinical practice

DETECTION OF METALLO BETA - LACTAMASES AMONG ENTEROBACTERIACEAE ISOLATES AT A TERTIARY CARE HOSPITAL, SOUTH INDIA

Background: The spread of carbapenem resistant bacteria has caused grave concern due to the limited choice in antibiotics for treating infections caused by them. The emergence of  metallo beta-lactamse (MBL) producing  gram negative bacilli poses a therapeutic challenge and is of serious concern for infection control in hospital environment. Materials & Methods: A total of 475 non repeat clinical isolates of family Enterobacteriaceae were included in the study. Resistance to imipenem was determined in isolates by disc diffusion & minimum inhibitory concentration (MIC) method. Imipenem resistant  isolates  were tested for MBL production by combined disc diffusion test and modified Hodge test. Results: Out of the 475 Enterobacteriaceae strains,  20 showed resistance to imipenem. MBL activity was detected in all 20 (4.2%) isolates by combined disc diffusion test, in 18 isolates by modified Hodge test. The MBL producing isolates included clinical strains of Klebsiella spp (45%), E. coli (40%), Citrobacter spp (15%).  Majority of the MBL isolates were from Intensive care unit (65%), from patients with comorbid conditions and with invasive devices.  MBL producing isolates showed high level of resistance to aminoglycosides and fluoroquinolones but all were susceptible to colistin. Conclusion: The need of the hour is to detect MBL producing isolates for better patient outcomes, to execute prompt infection control measures and decrease the escalation of resistance