Hypervirulent Klebsiella pneumoniae is a highly pathogenic variant of Klebsiella pneumonae, which represents a global public health issue because it is very virulent and spreads easily. The objectives of this study were to assess the predominance of hvKp among health care-associated infections in intensive care units of Tanta University Hospital and to compare hvKp with classical K. pneumoniae (cKp) in terms of antibiotic resistance, virulence, and molecular features. The study included 300 patients suffering from HAIs from different ICUs of Tanta University Hospitals. K. pneumoniae isolates were identified and subjected to string testing and antibiotic susceptibility testing, and the tissue culture assay for biofilm formation and polymerase chain reaction (PCR) tests were performed for the identification of capsular genes (K1, K2, K57) and virulence genes (rmpA, rmpA2, iuc A). Fifty-seven K. pneumonaie isolates were isolated. A total of 21 (36.8%) of them were hvKp and 36 (63.15%) were cKp. Significantly higher antibiotic resistance was detected in the cKp group. There was a significant difference between biofilm formation between cKp and hvKp isolates (p < 0.004*). iucA, rmpA2, and K1 genes were significantly associated with hvKp. The string test shows 100% sensitivity and negative predictive value for the detection of hvKp. Consequently, using the string test alone for the screening of hvKp is required. However, combining aerobactin-positive with hypermucoviscous isolates while screening for hvKp is crucial.

Background: Oral candidiasis is an opportunistic infection of the oral cavity that can be distributed via the bloodstream, resulting in serious systemic candidiasis. Because of the toxicity and side effects of antifungal agents, research on the antifungal impact of silver nanoparticles (AgNPs) is necessary. Methods: Oral swabs were collected from fifty patients with oral candidiasis for the isolation and identification of candida species by automated Vitek 2. Biofilm formation was evaluated using a tissue culture plate assay. The anti-candida and anti-biofilm effects of AgNPs on isolated Candida species were investigated using agar-well diffusion and microdilution methods. Results: Candida albicans was the predominant isolate, accounting for 51.9%. Biofilm formation was identified in 63.5% of candida isolates, commonly in isolates of C. albicans (57.6%), C. tropicalis (30.3%), and C. parapsilosis (12.1%), while all C. glabarata isolates could not form a biofilm. A significant decrease in the growth of candida isolates was detected at 500 μg/mL of AgNPs. The largest zone of inhibition (22.6 mm ± 0.6) was detected with C. albicans, then C. parapsilosis (20.4 mm ± 0.9), C. tropicalis (18.4 mm ± 0.5), and C. glabrata (16.5 mm ± 0.6) with a statistically significant difference. AgNPs inhibited the biofilm production of Candida species up to 100% at 500 μg/ml. Generally, the AgNPs anti-biofilm activity was significantly higher against C. albicans than C. tropicalis and C. parapsilosis at concentrations ranging from 31.25 to 250 μg/ml. Conclusions: Synthesized AgNPs showed antifungal and antibiofilm activity against all albicans and non-albicans Candida species.

Background: Central line-associated bloodstream infections (CLABSI) are considered the third most frequent cause of healthcare-associated infections (HCAI). Objectives: This study aimed to detect infection rate of CLABSI in surgical intensive care unit (ICU), and to identify bacteriological profile & antibiotic sensitivity of infecting organisms causing CLABSI. Methods: This study was carried out on 450 ICU patients with CVC inserted for more than 2 days of admission in the hospital with no infection at the time of admission to the ICU, having the criteria of CLABSI [fever < 38°C or high leucocytic count <10000/ml], and no remote site of infection who were admitted to the ICU for at least 48 hours. Results: CLABSI was present in 57 (12.67%) of all included patients. Diabetes mellitus, hypertension, renal failure , cancer , care of central line, and mortality rate were statistically significant risk factors in positive CLABSI patients (P value <0.05). While, age, gender, length of hospital stay, site of central line (Subclavian, jagular, femoral), and use of other associated devices were statistically insignificant between positive and negative CLABSI patients. Conclusions: Our study revealed that the prevalence of bacterial pathogens was high and caused by both Gram positive and Gram negative bacteria. Unfortunately, most of the pathogens were multi drug resistant organisms. CLABSI was significantly associated with care of central line and mortality rate.

Background: Staphylococcus aureus has developed antibiotic resistance, a global challenge that makes managing infections difficult. The accessory gene regulator (agr) is a quorum-sensing system virulence regulator. Objectives: The objective of this study was to investigate the relations between agr types, antimicrobial resistance, and biofilm formation among S. aureus isolates. Methodology: Various clinical samples from patients with nosocomial infections in ICUs of Tanta University Hospitals were included. S. aureus isolates were identified, antibiotic sensitivity testing was done using Kirby-Bauer disk diffusion method, mecA gene screening by PCR, the tissue culture plate technique was utilized to evaluate the biofilm formation, and agr typing was detected by multiplex PCR. Results: Seventy-six S. aureus isolates were obtained; they were highly resistant to ampicillin (90.8%), imipenem (73.7%) and no resistance for vancomycin or linezolid in all isolates. 56 isolates (73.68%) were MRSA while 20 isolates (26.31%) were MSSA. There is a significant variation in biofilm formation between MSSA and MRSA isolates. Both biofilm-forming and non-forming isolates exhibited a rise in antibiotic resistance. Among all isolates, agr I was the commonest type (61.8%) followed by agr III (18.4%). The existence of agr I was linked to biofilm development. Isolates with agr I were resistant to Erythromycin, Gentamycin, Ciprofloxacin, Levofloxacin, and Tetracycline among MRSA isolates. Conclusion: High rate of antibiotic resistance, and biofilm production among agr-positive S. aureus isolates were detected in ICUs. Therefore, the development of a new effective anti-virulence agent is promising for the treatment of S. aureus infection.