Purpose: The emergence of Neisseria gonorrhoeae strains that are resistant to the most commonly used antibiotics represents a great concern for global public health. This challenges the effectiveness of clinical treatment regimens and demands the development of alternative antigonococcal agent. In this regard, chitosan nanoparticles (CNPs) are known to have antimicrobial activity against a wide range of pathogens. Thus, they have become a potential candidate for combatting this era of multi-drug resistance. This study aims to formulate CNPs, characterize their physicochemical properties, and examine their antimicrobial activity against gonococcus. Materials and Methods: The ionic gelation method was used to prepare CNPs of different concentrations. Characterization for their particle size (PZ), polydispersity index (PDI), and zeta potential (ZP) was performed. The anti-microbial activity of CNPs was investigated against 13 WHO N. gonorrhoeae reference strains, using the broth dilution method. Cytotoxicity of CNPs and their effect on bacterial adhesion to HeLa cells were investigated. Results: The average PZ and ZP of the prepared NPs were increased when the concentration of chitosan was increased from 1 to 5 mg/mL and found to be in the range of 193 nm ± 1.9 to 530 nm ± 13.3, and 14 mV ± 0.5 to 20 mV ± 1, respectively. Transmission electron microscopes (TEM) images revealed spherical NPs, and the NPs had a low PDI value of ≤ 0.27. The formed CNPs produced antibacterial activity against all tested strains, including those resistant to multiple antibiotics, with a minimum inhibitory concentration (MIC90) of 0.16 to 0.31 mg/mL and a minimum bactericidal concentration (MBC) of 0.31 to 0.61 mg/mL. Of note, at all MIC90 and MBC, the CNPs had no significant cytotoxic effect on HeLa cells and reduced bacterial adhesion to these cells at MBC doses. Conclusion: The present work findings suggest the potential of the CNPs for the treatment of gonorrhoea.
Carbapenem-resistant Enterobacterales (CRE) is an urgent public health threat of significant global concern. Few observational studies have evaluated the clinical outcomes for treatment of CRE harbouring OXA-48 or NDM genes with ceftazidime/avibactam. Previous findings showed lower 30 day mortality with ceftazidime/avibactam ranges between 8.3% and 22%. This single-centre retrospective cohort study included adult patients aged ≥18 years admitted to King Abdulaziz Medical City (KAMC) who had received ceftazidime/avibactam for at least 72 h for infections caused by CRE with genes encoding for carbapenemase production (CP-CRE). A total of 211 patients, mostly male (57%), having CP-CRE infections treated with ceftazidime/avibactam were included, with an average age of 62 years. More than 50% of patients were critically ill, for which 46% received invasive ventilation and 36% were on inotropes. The most frequent infectious disease was hospital/ventilator-acquired pneumonia with Klebsiella pneumoniae being the most frequent causative pathogen. The majority of isolates harboured OXA-48 (81%), followed by NDM ± OXA-48 (19%). The overall clinical cure and 30 day mortality was 78% and 21% respectively (stratified per gene: 79% and 21.6% for OXA-48 and 75% and 17.5% for NDM ± OXA-48). This was the largest study that evaluated clinical outcomes associate with CP-CRE harbouring OXA-48 gene infections treated with ceftazidime/avibactam. Clinical cure and 30 day mortality were consistent with those of previous studies. Findings suggested that combination therapy with ceftazidime/avibactam had no direct impact on clinical outcomes for CP-CRE with OXA-48.
Spondylodiscitis is rare yet the most common form of spinal infection. It is characterized by inflammation of the intervertebral disk space and adjacent vertebral body. In Western countries, the incidence of spondylodiscitis is increasing. Clinical outcomes most commonly reported in the literature are the 1-year mortality rate (range, 6%–12%) and neurologic deficits. This multicenter retrospective cohort study assessed patients diagnosed with infectious spondylodiscitis who received treatment at King Abdulaziz Medical City in Riyadh and Jeddah, Saudi Arabia. All enrolled patients were ≥18 years old and were diagnosed per radiologic and microbiological findings and clinical manifestations between January 2017 and November 2021. This study enrolled 76 patients with infectious spondylodiscitis, with a median age of 61 years. All patients presented with back pain for a median 30 days. Patients were stratified into 3 groups based on the causative pathogen: brucellar spondylodiscitis (n = 52), tuberculous spondylodiscitis (n = 13), and pyogenic spondylodiscitis (n = 11). All laboratory data and biochemical markers were not significantly different. However, C-reactive protein, erythrocyte sedimentation rate, and white blood cells were significantly different in the pyogenic spondylodiscitis group, with medians of 121 mg/dL (P = .03), 82 mmol/h (P = .04), and 11.2 × 109/L (P = .014), respectively. Back pain is a common clinical feature associated with infectious spondylodiscitis. The immense value of microbiological investigations accompanied with histologic studies in determining the causative pathogen cannot be emphasized enough. Treatment with prolonged intravenous antimicrobial therapy with surgical intervention in some cases produced a cure rate exceeding 60%.
24 November 2021 in Journal of Infection and Public Health
Immunomodulators, including dexamethasone (DEX), have been recommended by the Infectious Disease Society of America (IDSA) to treat moderate, severe, and critical COVID-19. Tocilizumab (TCZ) was added to the treatment recommendations based on recent data from two large randomized controlled trials and its potential synergistic effect with DEX. We included adult patients admitted from June until October 2020 with a PCR confirmed SARS-CoV-2 infection. 135 patients with severe to critical COVID-19 and received TCZ and/or corticosteroid or DEX were retrospectively evaluated and followed until hospital discharge or death. The cohort was divided into two different groups of patients; TCZ group received TCZ ± corticosteroid, N = 100 and DEX group received DEX, N = 35. Groups were analyzed for hospital mortality. The rate of hospital mortality was 36% in TCZ and 37% in the DEX group, p = 0.91. Age of 60 years and above was associated with higher mortality rate with OR = 1.030 and 95% CI = (1.004, 1.057). More than 50% of patients required MV in both groups. Development of bacterial or fungal infection post immunomodulator were similar in TCZ and DEX groups, 29% vs. 31.4%. Our study revealed that age of 60 years and above is the only factor associated with higher mortality rate regardless of the type of immunomodulator therapy. Findings of this study also revealed the lack of synergistic effect between TCZ and DEX on the hospital mortality.
Staphylococcus aureus bacteremia is a life-threatening condition associated with a substantial financial burden on the health care system. The use of the GeneXpert ® methicillin-resistant S. aureus (MRSA)/ S. aureus blood culture (BC) test for the identification of S. aureus may influence antibiotic stewardship and clinical outcomes. This study assessed the clinical and financial impact of utilizing GeneXpert MRSA/SA in combination with criterion-based testing. The outcomes between October 1, 2018, and June 30, 2019, were evaluated in 65 adult patients who had positive BCs with Gram-positive cocci in clusters. GeneXpert MRSA/SA significantly shortened the time to optimal antimicrobial therapy by 1.7 days (2.5 vs. 44 hr, p < 0.0001). The cost saved because of interventions based on GeneXpert testing results was $4,121. GeneXpert testing has shortened the time to optimal therapy and positively impacted cost, although it had no significant effect on length of hospital stay and mortality rate.
3 December 2020 in Journal of Global Antimicrobial Resistance
Recent studies have shown that MRSA bacteremia with vancomycin MIC > 1 µg/mL is associated with a higher rate of treatment failure and a higher mortality rate. Daptomycin is an alternative to vancomycin, but has not been as well studied. The aim of this literature review was to evaluate effect of the MIC of daptomycin on the outcomes of S. aureus bacteremia. We conducted a literature search for the period from January 2010 to January 2019 using the MEDLINE and EMBASE databases. Four studies were included in the review. The outcomes were clinical cure and 30- or 60-day mortality. In two retrospective studies, 60-70% of S. aureus isolates had a low daptomycin MIC (≤0.5 µg/mL), patients with MRSA bacteremia who were treated with daptomycin had a lower mortality rate. In another study, patients with methicillin sensitive S. aureus bacteremia with low daptomycin MICs had lower risk of developing septic thrombophlebitis. One study showed that patients with MRSA bacteremia had a higher mortality rate if daptomycin MIC > 0.5 µg/mL. The included studies in this review suggest possible association between high daptomycin MIC and unfavorable clinical outcomes of S. aureus bacteremia. Further prospective studies are required to evaluate the impact of the daptomycin MIC on the clinical outcomes of S. aureus bacteremia.