Background: Methicillin resistant Staphylococcus aureus (MRSA) is an important cause of
nosocomial infections. Vancomycin is one of the mainstays for the cure of MRSA infections and
vancomycin MIC creep have been reported from different parts of the world. This study evaluated the
trends of vancomycin MIC among the MRSA and analysed its relationship with vancomycin
consumption.
Methods: During the six years of this retrospective study, the MIC of Oxacillin and Vancomycin of
all clinically relevant Staphylococcus aureus were retrieved from the automated Vitek-2 compact
system. The consumption rate of vancomycin in our hospital as the defined daily doses (DDDs) per
1000 bed-days were collected from Pharmacy services. The data obtained were statistically analysed.
Results: Out of 1,19,112 total samples processed 2.02% were found as Staphylococcus aureus among
which 44.7% were MRSA. Over the study period, all the MRSA isolates were susceptible to
vancomycin and there was a statistically significant increase in isolates with vancomycin MIC =1 µg/ml
depicting the MIC creep phenomenon in our isolates. But a significant correlation between DDDs/1000
bed days of vancomycin and increase in MIC range could not be established.
Conclusion: There is a dire need to identify the trend of vancomycin MICs in our local area to assess
the existence of creep trend and warn the clinicians of these disastrous strains. Sensitization about this
type of MRSA MIC creep among the primary health physician is also needed to implement the control
measures and limit its spread in communities.

Background:   Microbiological laboratories are critical for diagnostic testing and infectious disease surveillance. However, they are prone to microbial contamination, which can impact diagnostic accuracy and patient safety. This study aimed to evaluate the pattern of bacterial contamination in a microbiological laboratory at a super-specialized hospital in Delhi and to develop effective contamination control strategies.

Methods:   A cross-sectional study was conducted from August 2022 to December 2022, involving the collection of 4000 surface swab samples from various laboratory areas. Samples were cultured on blood and MacConkey agar, incubated for 24 hours, and bacterial colonies were identified using standard microbiological techniques. Statistical analyses were performed to assess contamination levels and the effectiveness of cleaning protocols.

Results:   The culture positivity rate was 39%, with 1563 out of 4000 samples detected as  positive for bacteria. Of these, 90.47% had multiple isolates, with the most common being aerobic spore-forming bacilli, Staphylococcus aureus, Escherichia coli, and Acinetobacter baumannii. Laboratory workstations and incubators showed the highest contamination. Cleaning significantly reduced bacterial presence, with a p-value < 0.00001. Specific organisms isolated from different areas included ASB, Micrococcus,  Coagulase-negative staphylococcus species, Staphylococcus aureus.

Conclusion:   The study highlights substantial bacterial contamination across laboratory surfaces, underscoring the need for stringent contamination control measures. Key recommendations include routine cleaning and disinfection, staff training on aseptic techniques, environmental monitoring, and strict adherence to sterilization and biosafety protocols. These measures are essential to maintain diagnostic accuracy and safeguard personnel against laboratory-acquired infections.

Background:   Pseudomonas spp. is one of the major threat of nosocomial infections in hospitalized patients due to combination of various virulence factors and weakened host defense. Even more problematic is the development of resistance during the course of therapy, a complication which has been shown to double the length of hospitalization and overall cost of patient care So, it is important to know prevalence of Pseudomonas spp.in various clinical infections.

Methods:   This hospitalized based prospective study includes 250 Pseudomonas isolates subjected to identification by microscopy, culture, speciation and Antibiotic Sensitivity tests with standard guidelines.

Results:   In this study out of 2051 clinical samples, the most common was E. coli (38.23%), followed by Klebsiella (15.94%) and 250 (12.19%) Pseudomonas spp. were isolated. Of them,233 were of P. aeruginosa,141(56.4%) were from pus. Diabetes mellitus and post operative infections each 33(13.2%) were the most commonly known predisposing factors for  patients from whom Pseudomonas were isolated, P. aeruginosa isolates were most resistant to Piperacillin (78%) while  least resistant to Meropenem and Imipenem with resistance of 28% and 22% respectively.

Conclusion:   The study underlines the importance of preventing the spread of the resistant bacteria. For this, it is critically important to have strict antibiotic policies while surveillance programmes for multidrug resistant organisms and infection control procedures need to be implemented. In the meantime, it is desirable that the antibiotic susceptibility pattern of Pseudomonas in specialized clinical units to be continuously monitored and the results readily made available to clinicians so as to minimize the resistance. 

Background:   Truperella pyogenes (T. pyogenes) is a gram-positive bacterium which can lead to visceral abscesses in cattle. The abscesses may be found in internal organs such as spleen, kidney, liver, lungs and skin. The aim of this study is to focus on spleen abscesses due to T. pyogenes.

Methods:   The whole spleen was sent to the laboratory and the causative agent was evaluated using isolation methods and biochemical tests based on the colonies.

Results:   The appearance of isolated colonies and the results of biochemical tests confirmed the presence of T. pyogenes in the spleen lesions.

Conclusion:   The current results identified T. pyogenes as the only isolated bacterium in a case of visceral abscess. This study emphasizes the necessity of implementing effective planes such as improving sanitation, reducing stressful conditions, feeding cattle by balanced diet, avoiding sudden changes in grain intake, and controlling other diseases to prevent the chronic economical losses of visceral infection with T. pyogenes.

Background:   Resistance to carbapenem as a most effective antibiotic for treatment of Acinetobacter baumannii infection can make a complication in treatment of patients. Several phenotypic methods have been introduced for detection of the carbapenemase producing strains. The aim of this study was determined the efficacy of the newest method that is called Blue-CARBA test for identification of the carbapenemase producing Acinetobacter baumannii.

Methods:   In this cross sectional study 63 Acinetobacter baumannii have been collected from burn wounds infection. Carbapenem susceptibility testing has been conducted by disc diffusion agar method after identification The Modified Hodge test and Blue-CARBA test was performed for all carbapenem resistant strains. Vim, imp, oxa-23, oxa-48, NDM-1, SPM-1 and kpc genes have been detected as a most common carbapenemase in Acinetobacter baumannii.

Results:   Sequence analysis showed that 54 isolates include oxa-23 gene. Eight and 5 strains carried vim and kpc genes respectively. MHT and Blue-CARBA test were positive in 27 and 28 of imipenem resistant strains, respectively.

Conclusion:   According to the results of this study, Blue-CARBA test showed similar power of carbapenemase producing identification with Modified Hodge test and can be purposed use in place of MHT for detection of carbapenemase.

Background:   Exotoxin A (ExoA) is one of the most known and important virulence factors of Pseudomonas aeruginosa. This toxin is the cause of ADP-ribosylation in eukaryutic Elongation Factor-2 (EF-2), which results in the protein synthesis inhibition. Recent studies had shown immunostimulational characteristics of detoxified the ExoA. Our aim in this study was to evaluate the immunological properties of detoxified ExoA by Serum Bactericidal assay, in comparison with ELISA.

Methods:   The production of ExoA was done on the ExoA-producing strain, Pseudomonas aeruginosa PA103, provided by Pasteur institute of Iran. After culture in semi-industrial scale, it was detoxified and purified by dialysis. The dialysate was injected to mice and rabbit. After 3weeks, the total sera were collected. Serum bactericidal assay & ELISA were performed.

Results:   The results had shown a significant increase of antibodies against detoxified ExoA of 1/16 and antibody in ELISA method. Also, this has shown more antigenecity & immunogenosity by SBA method.

Conclusion:   To conclude the study that has been done here, SBA has much higher advantages than ELISA, in determining the immunological properties of Exo A. Furthermore, since Exo A could act as a hapten, many other subunits from other bacteria or viruses could be conjugated on Exo A and form multi-target vaccines.

Background:   Lung infection is a global health problem associated with high morbidity and mortality world-wide and increasing rates of hospitalization. Polymicrobial pleuropulmonary infection is define as the simultaneous isolations of two or more other organisms from lung secretions culture which are associated with increased infection severity outcome compared to monomicrobial Pleuropulmonary infections. The aim of this study is evaluation of polymicrobial pulmonary infection rate during March 2019 to   February 2024 at a Tertiary Hospital in Mashhad, Eastern Iran.

Methods:   This single-center retrospective study was conducted from   March 2019 to   February 2024 in Shahid Kamyab Hospital, Mashhad, Iran. Our data in this study included 429 patients with pulmonary infection in the five years studied, which 34 patients were under 18 years old and 395 patients were over 18 years old. The total number of positive lung samples of these patients was 532. In this study, we investigated the prevalence of polymicrobial lung infections along with the bacteria that cause them.

Results:   A total of 532 positive lung culture specimens were included, which 196 cases were polymicrobial (36.8 %) and 336 cases were monomicrobial (63.2 %). this study showed that Acinetobacter baumannii had the most frequency among other bacteria which cause polymicrobial pulmonary infections (32 %). 

Conclusion:   Pulmonary infection is a serious complication, which significantly increases mortality rate and medical costs. In this retrospective study we have found that polymicrobial pulmonary infections in patients in this hospital was 36.8 % that Acinetobacter baumannii was the most cause of infections.

Background:   Cupriavidus pauculus is a gram-negative, aerobic bacillus found in environment. This microorganism can rarely cause serious infections in immunocompromised patients. Catheter-related bloodstream infection caused by Cupriavidus pauculus is a hospital acquired infection which is an infrequent state with very few cases reported in the literature. In this research, we report the first case of Cupriavidus pauculus infection in Iran.

Methods:   Blood cultures were performed using the BD BACTEC (Becton, Dickinson, USA) automated haemoculture system and subsequently the gram negative bacilli with regular borders, smooth consistency and dry appearance colonies were identified as Cupriavidus pauculus by the BD Phoenix M50 Compact automated system.

Results:   In this paper, we report the first case of Cupriavidus pauculus infection in Iran.  this strain was susceptible to Piperacillin-Tazobactam, Ceftazidime, Cefepime, Trimethoprim-Sulfamethoxazole, Ciprofloxacin, Levofloxacin and resistant to Cefazolin, Ampicillin and Amoxicillin-Clavulanate and is intrinsically resistant to Aminoglycosides, first generation Cephalosporins, Aminopenicillins, Ampicillin-Sulbactam, Ticarcillin and Ceftriaxone.

Conclusion:   There are little evidence in the literature about infections caused by Cupriavidus pauculus. Catheter-related bloodstream infection caused by Cupriavidus pauculus is an infrequent infection in humans, but this microorganism should be considered as a potential pathogen in hospitalized immunocompromised patients which can cause serious infections in these individuals, requiring broad-spectrum antibiotic therapy.

Background:   Chromobacterium violaceum, a rare Gram-negative bacillus, is found in tropical and subtropical soils and stagnant water. Human infections, though uncommon, are often severe and rapidly progress to septicaemia with high mortality. Diagnosing C. violaceum infections in paediatric cases is challenging due to their clinical overlap with other bacterial and viral infections.

Methods:   Blood and tissue cultures were analysed using automated VITEK 2 and conventional biochemical tests, which identified C. violaceum and guided the antimicrobial therapy.

Results:   Persistent fever and necrotic lesions suggested bacterial sepsis rather than a viral cause. Blood and tissue cultures revealed C. violaceum, sensitive to aztreonam, gentamicin, imipenem, meropenem, chloramphenicol, ciprofloxacin, and cotrimoxazole. The patient was successfully treated with meropenem, cotrimoxazole, and gentamicin over three weeks, resulting in clinical improvement and discharge.

Conclusion:   This case highlights the diagnostic challenges in distinguishing C. violaceum infections from other pathogens. Early identification through automated VITEK 2 and sensitivity testing facilitated effective treatment, underscoring the importance of considering C. violaceum in septic cases with necrotic skin lesions after water exposure in endemic areas. Prompt diagnosis and targeted therapy are essential for managing this life-threatening infection.

Background:   Various viruses and bacteria are involved in the incidence of respiratory tract infections (RTIs), and viruses account for the majority of RTIs. Given the high economic and therapeutic burden of RTIs, the current review aimed to present a brief but comprehensive overview of the most important viral etiologies of RTIs along with their complications, manifestations, and transmission routes. A comprehensive literature search was performed in electronic databases including Google Scholar, Scopus, PubMed, and Web of Science to find articles related to the scope of this research, published in English. Eligible studies providing evidence on viral respiratory tract infections, their clinical complications, symptoms, and causes were included in this review.

Conclusion:    Considering the diversity and prevalence of viral RTIs and the economic and therapeutic burden imposed on health systems, it is necessary to raise public awareness about their transmission methods and preventive measures to control and manage these infections.