Screening for Microbial Contamination of Multi-dose Lignocaine Vials in a Dental Hospital: A Prospective Study.

Aim: Multidose vials (MDVs) for local anesthetic injections are routinely used in dental practice. MDVs contain multiple doses of a parenteral drug intended for administration to the same or multiple patients. Potentially harmful microbes have been shown to be able to live and occasionally multiply in MDVs if not handled aseptically. The goal of this study thus was to evaluate the bacterial and fungal contamination (FC) of lignocaine MDVs after use in a dental hospital. Materials and methods: A total of 27 MDVs of lignocaine free of any microbial contamination were distributed to different departments of the dental hospital and they were asked to use them on patients routinely. The samples were recollected from the departments either at the end of the 28th day or as and when the contents in the MDVs reached a predetermined level marked on the bottle during its usage, whichever was earlier. These leftover samples were subjected to a microbiological investigation by inoculation into thioglycolate broth and subsequent subculturing onto agar plates. Results: None of the inoculated broths showed turbidity. Subcultured agar plates, even on the 7th day of incubation, did not show any bacterial or fungal growth. The lignocaine MDVs tested after use were thus found to be sterile. Conclusion: There was no bacterial or FC detected in MDVs of lignocaine subjected to testing after use in the dental hospital. Clinical significance: Multidose vials (MDVs) continue to be used in clinics for economic reasons. But the clinician opting for MDVs should be conscious of their potential for microbial contamination and should meticulously follow the protocol for their aseptic use. How to cite this article: Renu SM, Rao AP, Biranthabail D, et al. Screening for Microbial Contamination of Multi-dose Lignocaine Vials in a Dental Hospital: A Prospective Study. Int J Clin Pediatr Dent 2023;16(5):678-680.

Rapid method for detecting and differentiating Mycobacterium tuberculosis complex and non-tuberculous mycobacteria in sputum by fluorescence in situ hybridization with DNA probes.

OBJECTIVE: In resource-limited tuberculosis-endemic countries, Mycobacterium tuberculosis in sputum is mainly detected by acid-fast bacillus (AFB) staining and the identification of sputum-derived cultures. PCR techniques are practical only in well-resourced laboratories. This study investigated the application of a rapid, simple, and inexpensive fluorescence in situ hybridization (FISH) assay to identify and differentiate M. tuberculosis complex (MTBC) from non-tuberculous mycobacteria (NTM) in sputum. METHODS: The Mycobacterium/Nocardia Genus (MN Genus)-MTBC FISH assay performed in this study utilizes two different DNA probes labeled with different fluorescent molecules that hybridize respectively with 16S rRNA of the genus Mycobacterium and 23S rRNA of MTBC. The assay was tested on 202 patient sputum samples in Mangaluru, Karnataka State, India. Sputa were first liquefied and bacteria concentrated before performing the FISH assay and parallel culturing and AFB staining. The identities of cultured bacteria from DNA sequencing were compared with FISH assay findings from corresponding sputa. RESULTS: Of the 202 sputum samples tested, 67 reacted with both MN Genus-specific and MTBC-specific probes, none reacted only with the MTBC-specific probe, and 22 reacted only with the MN Genus-specific probe. The FISH assay yielded results in 2h and had a limit of detection of 2.2×104CFU/ml in sputum spiked with cultured M. tuberculosis. The diagnostic sensitivity, specificity, and positive and negative predictive values of the FISH assay for MTBC in patient sputa were 89.7%, 95.5%, 88.0%, and 92.6%, respectively. NTM were a significant cause of tuberculosis-like infections in Mangaluru. CONCLUSIONS: The MN Genus-MTBC dual probe fluorescence FISH assay previously applied to cultures can also be utilized in resource-limited tuberculosis-endemic countries for rapidly identifying and differentiating MTBC and NTM in sputum samples.

Antibiogram and genetic relatedness of clinical isolates of Enterococcus spp. in Mangalore, India.

INTRODUCTION: Drug-resistant Enterococcus species is a persisting clinical problem and may serve as a reservoir of resistant genes. The present study was undertaken in Mangalore, India to know the antibiogram and genetic relatedness of Enterococcus spp. isolated from clinical samples. METHODOLOGY: A total of 150 non-repetitive Enterococcus spp. isolated from clinical samples were subjected to antimicrobial susceptibility testing by Kirby Bauer disk diffusion method. Molecular typing of the isolates was done by Random amplification of polymorphic DNA (RAPD). RESULTS: Among the 150 isolates, 79 were from urine, 68 from pus and three from blood samples. Of this 58.7 % were E. faecalis and the remaining were E. faecium. Urinary isolates of E. faecium showed a higher percentage of antibiotic resistance when compared to E. faecium isolates from pus (p < 0.001). E. faecium from blood samples were resistant to ampicillin, penicillin, ciprofloxacin and were sensitive to vancomycin and teicoplanin. E. faecalis blood isolates were resistant to ciprofloxacin, penicillin, and erythromycin. 73% of Enterococcus isolates from pus were resistant to erythromycin. All the Enterococcus spp. were sensitive to vancomycin. Among the total Enterococcus isolates 44 were high-level aminoglycoside resistant (HLAR) by disc diffusion method which corresponded to MIC of > 500 µg/mL for gentamicin and > 1000 µg/mL for streptomycin. These isolates were subjected to RAPD, which showed similarity and differences in the banding patterns. CONCLUSIONS: Our study showed a baseline resistance among Enterococcus spp. in our area, which poses a challenge to the treating physicians and a reservoir for transmission of antibiotic resistant genes.

A Case of Lower Respiratory Tract Infection with Canine-associated Pasteurella canis in a Patient with Chronic Obstructive Pulmonary Disease.

This is the report of lower respiratory tract infection with Pasteurella canis in a chronic obstructive pulmonary disease (COPD) patient with history of casual exposure to cats. Pasteurella species are part of the oral and gastrointestinal flora in the canine animals. These organisms are usually implicated in wound infection following animal bites, but can also be associated with a variety of infections including respiratory tract infections.

Molecular characterization and clinical significance of New Delhi metallo-beta-lactamases-1 producing Escherichia coli recovered from a South Indian tertiary care hospital.

CONTEXT: The increased rate of infection by New Delhi metallo-beta-lactamases-1 (NDM1) producing Escherichia coli is a major concern since they show a high rate of drug resistance and are responsible for mortality and morbidity. AIMS: To characterize the NDM1 producing E. coli isolates and their impact on patients' clinical outcome. SETTINGS AND DESIGN: This descriptive study was carried out in a multi-specialty tertiary care hospital. MATERIALS AND METHODS: Three hundred nonrepeat strains of E. coli from inpatients were included in the study. Modified Hodge test and metallo-beta-lactamases (MBL) e-test were performed to detect carbapenemase and MBL activity. Polymerase chain reaction (PCR) technique was performed to detect NDM1. NDM1 positive isolates were further tested for plasmid mediated AmpC, blaCTX , blaSHV , blaTEM genes and also for phylogrouping by PCR methods. Treatment and patients' clinical outcome were also analyzed. RESULTS: Out of 300 isolates, 21 (7%) were MBL producers by phenotypic methods. Of this, 17 (81%) were NDM1 positives, among the NDM1 producers 6 (35%) isolates were belongs to phylogroups D followed by A 5 (29%), B1 4 (24%) and B2 2 (12%), 15 (88%) isolates were blaCTX-M positive suggestive of extended-spectrum beta lactamase producing strain and 7 (47%) were positive with CIT type of AmpC. With the follow-up of the patients, it was found that 12 (71%) recovered and 3 (18%) developed relapses, and mortality was seen in 2 (12%) patients. CONCLUSIONS: NDM1 producing isolates showed a high degree of drug resistance but can be treated with suitable antimicrobials, in the majority. Early detection and choice of appropriate antibiotics may help in reducing mortality and morbidity.