Monotherapy versus combination for the treatment of Stenotrophomonas maltophilia: a multicenter cohort study.

BACKGROUND: The aim of this study was to compare the safety and effectiveness of monotherapy versus combination therapy for the treatment of infections caused by S. maltophilia. METHODS: This retrospective, multicenter, cohort study included patients treated with either monotherapy or combination therapy for infections caused by S. maltophilia. Primary outcomes included overall in-hospital mortality, 30-day mortality, and clinical cure. Safety outcomes were also evaluated. Multivariable logistic regression was used as a control for confounding variables. RESULTS: A total of 407 patients were included, 330 patients received monotherapy and 77 patients received combination therapy. A total of 21% presented with concomitant bacteremia. After adjusting the differences between the two groups, there were no statistically significant differences between patients who received monotherapy versus combination therapy in clinical cure (55% vs 65%; OR, 0.72; 95% CI, 0.40-1.31) and overall in-hospital mortality (52% vs 49%; OR, 0.84; 95% CI, 0.45-1.57). However, patients who received monotherapy had a lower rate of 30-day mortality (28% vs 32%; OR, 0.45; 95% CI, 0.22-0.90) and acute kidney injury (9% vs 18%; OR, 0.35; 95% CI, 0.16-0.78). CONCLUSION: Clinical outcomes did not significantly differ in patients who received combination therapy versus monotherapy. More data are needed to validate these findings.

Novel ß-lactam-ß-lactamase inhibitors as monotherapy versus combination for the treatment of drug-resistant Pseudomonas aeruginosa infections: A multicenter cohort study.

BACKGROUND: Data comparing the clinical outcomes of novel ß-lactam-ß-lactamase inhibitors given in combination versus monotherapy for the treatment of multidrug-resistant (MDR) P. aeruginosa infections are lacking. METHOD: This retrospective cohort study included patients who received novel ß-lactam-ß-lactamase inhibitors as monotherapy or in combination for the treatment of MDR P. aeruginosa infections. The study was conducted between 2017 and 2022 in 6 tertiary care hospitals in Saudi Arabia. Overall in-hospital mortality, 30-day mortality, clinical cure, and acute kidney injury (AKI) were compared between recipients of monotherapy versus combination using multivariate logistic regression analysis. RESULT: 118 patients and 82 patients were included in monotherapy and combination therapy arms, respectively. The cohort represented an ill population with 56% in the intensive care unit and 37% in septic shock. A total of 19% of patients presented with bacteremia. Compared to monotherapy, combination therapy did not significantly differ in clinical cure (57% vs. 68%; P = 0.313; OR, 0.63; 95% CI, 0.36-1.14) in-hospital mortality (45% vs. 37%; P = 0.267; OR, 1.38; 95% CI, 0.78-2.45), or 30-day mortality (27% vs. 24%; P = 0.619; OR, 1.18; 95% CI, 0.62-1.25). However, AKI (32% vs. 12%; P = 0.0006; OR, 3.45; 95% CI, 1.67-7.13) was significantly more common in patients who received combination therapy. CONCLUSION: Novel ß-lactam-ß-lactamase inhibitors when used in combination with other antibiotics did not add clinical benefit compared to their use as monotherapy in the treatment of MDR P. aeruginosa infections. A Combination regimen was associated with an increased risk of nephrotoxicity.

External Validation of Obese/Critically Ill Vancomycin Population Pharmacokinetic Models in Critically Ill Patients Who Are Obese.

Obesity combined with critical illness might increase the risk of acquiring infections and hence mortality. In this patient population the pharmacokinetics of antimicrobials vary significantly, making antimicrobial dosing challenging. The objective of this study was to assess the predictive performance of published population pharmacokinetic models of vancomycin in patients who are critically ill or obese for a cohort of critically ill patients who are obese. This was a multi-center retrospective study conducted at 2 hospitals. Adult patients with a body mass index of ≥30 kg/m2 were included. PubMed was searched for published population pharmacokinetic studies in patients who were critically ill or obese. External validation was performed using Monolix software. A total of 4 models were identified in patients who were obese and 5 models were identified in patients who were critically ill. In total, 138 patients who were critically ill and obese were included, and the most accurate models for these patients were the Goti and Roberts models. In our analysis, models in patients who were critically ill outperformed models in patients who were obese. When looking at the most accurate models, both the Goti and the Roberts models had patient characteristics similar to ours in terms of age and creatinine clearance. This indicates that when selecting the proper model to apply in practice, it is important to account for all relevant variables, besides obesity.

Whole genome sequencing of resistance and virulence genes in multi-drug resistant Pseudomonas aeruginosa.

BACKGROUND: Pseudomonas aeruginosa is an opportunistic bacterium that causes serious hospital-acquired infections. To assess the risk of clinically isolated P. aeruginosa to human health, we analyzed the resistance and virulence mechanisms of a collection of clinical isolates. METHODS: This was a retrospective study in which P. aeruginosa isolates collected from January 1, 2018 to August 31, 2019 were analyzed using phenotypic and whole-genome sequencing (WGS) methods. The analysis included 48 clinical samples. Median patient age was 54.0 (29.5) years, and 58.3% of patients were women. Data from the microbiology laboratory database were reviewed to identify P. aeruginosa isolates. All unique isolates available for further testing were included, and related clinical data were collected. Infections were defined as hospital acquired if the index culture was obtained at least 48 h after hospitalization. RESULTS: High-risk P. aeruginosa clones, including sequence types (STs) ST235 and ST111, were identified, in addition to 12 new STs. The isolates showed varying degrees of biofilm formation ability when evaluated at room temperature, along with reduced metabolic activity, as measured by metabolic staining, suggesting their ability to evade antimicrobial therapy. Most isolates (77.1%) were multidrug resistant (MDR), with the highest resistance and susceptibility rates to beta-lactams and colistimethate sodium, respectively. CONCLUSIONS: The MDR phenotypes of the examined isolates can be explained by the high prevalence of efflux-mediated resistance- and hydrolytic enzyme-encoding genes. These isolates had high cytotoxic potential, as indicated by the detection of toxin production-related genes.

Ceftolozane-Tazobactam Versus Ceftazidime-Avibactam for the Treatment of Infections Caused by Multidrug-Resistant Pseudomonas aeruginosa: a Multicenter Cohort Study.

Ceftolozane-tazobactam (C-T) and ceftazidime-avibactam (CAZ-AVI) are two novel antimicrobials that retain activity against resistant Pseudomonas aeruginosa. The comparative effectiveness and safety of C-T versus CAZ-AVI remain unknown. A retrospective, multicenter cohort study was performed in six tertiary centers in Saudi Arabia and included patients who received either C-T or CAZ-AVI for infections due to multidrug-resistant (MDR) P. aeruginosa. Overall in-hospital mortality, 30-day mortality, and clinical cure were the main study outcomes. Safety outcomes were also evaluated. A multivariate analysis using logistic regression was used to determine the independent impact of treatment on the main outcomes of interest. We enrolled 200 patients in the study (100 in each treatment arm). A total of 56% were in the intensive care unit, 48% were mechanically ventilated, and 37% were in septic shock. Approximately 19% of patients had bacteremia. Combination therapy was administered to 41% of the patients. The differences between the C-T and CAZ-AVI groups did not reach statistical significance in the overall in-hospital mortality (44% versus 37%; P = 0.314; OR, 1.34; 95% CI, 0.76 to 2.36), 30-day mortality (27% versus 23%; P = 0.514; OR, 1.24; 95% CI, 0.65 to 2.35), clinical cure (61% versus 66%; P = 0.463; OR, 0.81; 95% CI, 0.43 to 1.49), or acute kidney injury (23% versus 17%; P = 0.289; OR, 1.46; 95% CI, 0.69 to 3.14), even after adjusting for differences between the two groups. C-T and CAZ-AVI did not significantly differ in terms of safety and effectiveness, and they serve as potential options for the treatment of infections caused by MDR P. aeruginosa.

Population pharmacokinetics of vancomycin in very low birth weight neonates.

Introduction: Vancomycin dosing in very low birth weight (VLBW) neonates is challenging. Compared with the general neonatal population, VLBW neonates are less likely to achieve the vancomycin therapeutic targets. Current dosing recommendations are based on studies of the general neonatal population, as only a very limited number of studies have evaluated vancomycin pharmacokinetics in VLBW neonates. The main aim of this study was to develop a vancomycin population pharmacokinetic model to optimize vancomycin dosing in VLBW neonates. Methods: This multicenter study was conducted at six major hospitals in Saudi Arabia. The study included VLBW neonates who received vancomycin and had at least one vancomycin serum trough concentration measurement at a steady state. We developed a pharmacokinetic model and performed Monte Carlo simulations to develop an optimized dosing regimen for VLBW infants. We evaluated two different targets: AUC0-24 of 400-600 or 400-800 µg. h/mL. We also estimated the probability of trough concentrations >15 and 20 µg/mL. Results: In total, we included 236 neonates, 162 in the training dataset, and 74 in the validation dataset. A one-compartment model was used, and the distribution volume was significantly associated only with weight, whereas clearance was significantly associated with weight, postmenstrual age (PMA), and serum creatinine (Scr). Discussion: We developed dosing regimens for VLBW neonates, considering the probability of achieving vancomycin therapeutic targets, as well as different toxicity thresholds. The dosing regimens were classified according to PMA and Scr. These dosing regimens can be used to optimize the initial dose of vancomycin in VLBW neonates.

Evaluation of vancomycin individualized model-based dosing approach in neonates.

BACKGROUND: Vancomycin is commonly used to treat methicillin-resistant staphylococcal infections in neonates. Consensus on its ideal dosing in neonates has not been achieved. Model-based dosing recently has evolved as an important tool to optimize vancomycin initial dosing. The aim of this is to evaluate a population pharmacokinetic model-based approach in achieving the vancomycin therapeutic target of an AUC0-24 400 as recommended by the recent IDSA treatment guidelines. This model was implemented as a simple Excel calculator to individualize and optimize vancomycin initial dosing in neonates. METHODS: An Excel calculator was developed using a previously published population pharmacokinetic model in neonates. It was evaluated using retrospectively retrieved data. For each patient, the initial empiric dose was calculated using the proposed Excel model and the most widely used neonatal dosing references. The probability of achieving the target AUC0-24 of >400 mg h/L using the model-based method was calculated and compared with that of the empiric doses using other references. RESULTS: This analysis included 225 neonates. The probability of achieving the target AUC0-24 >400 was 89% using our model-based approach compared with 11%-59% using tertiary neonatal dosing references (p < 0.01 for all comparisons). CONCLUSION: These innovative personalized dosing calculators are promising to improve vancomycin initial dosing in neonates and are easily applicable in routine practices.

Clinical characteristics and outcome of mucormycosis: A multi-center retrospective analysis in Saudi Arabia over 11 years.

Background: Mucormycosis is a life-threatening fungal infection with variable epidemiology between countries. Limited data are available locally; we aim to describe the clinical spectrum and outcome of mucormycosis in Saudi Arabia. Methods: A retrospective multi-center study including all patients with clinical and pathological evidence of mucormycosis in 3 tertiary care centers in Saudi Arabia from January 2009 to December 2019. Results: Thirty-three patients were identified during the study period. The mean age was 42 years. People with diabetes accounted for 48% of the patient population. The most common site of infection was cutaneous (27%), followed by isolated sinusitis (21%) and pulmonary and rhino-orbital-cerebral mucormycosis (each 18%). The most common isolated species were Rhizopus (50%) and Mucor (15%). Most patients received medical therapy with amphotericin B (79%), and more than half were treated surgically. The 1-year mortality rate reached 48%, with higher mortality observed in disseminated and rhino-orbital-cerebral infections than in other sites. Conclusion: Our study addressed the epidemiology of mucormycosis in Saudi Arabia and showed comparable patterns of clinical and mycological aspects to worldwide reports. Further studies are needed to evaluate mucormycosis risk factors and prognosis based on the species, site of infection and therapy type.

Analyzing central-line associated bloodstream infection prevention bundles in 22 countries: The results of ID-IRI survey.

BACKGROUND: Because central line-associated bloodstream infections (CLABSIs) are a significant complication of central venous access, it is critical to prevent CLABSIs through the use of central line bundles. The purpose of this study was to take a snapshot of central venous access bundles in various countries. METHODS: The participants in intensive care units (ICUs) completed a questionnaire that included information about the health center, infection control procedures, and central line maintenance. The countries were divided into 2 groups: those with a low or low-middle income and those with an upper-middle or high income. RESULTS: Forty-three participants from 22 countries (46 hospitals, 85 ICUs) responded to the survey. Eight (17.4%) hospitals had no surveillance system for CLABSI. Approximately 7.1 % (n = 6) ICUs had no CLABSI bundle. Twenty ICUs (23.5%) had no dedicated checklist. The percentage of using ultrasonography during catheter insertion, transparent semi-permeable dressings, needleless connectors and single-use sterile pre-filled ready to use 0.9% NaCl were significantly higher in countries with higher and middle-higher income (P < .05). CONCLUSIONS: Our study demonstrated that there are significant differences in the central line bundles between low/low-middle income countries and upper-middle/high-income countries. Additional measures should be taken to address inequity in the management of vascular access in resource-limited countries.

The COVID-19 vaccination acceptance/hesitancy rate and its determinants among healthcare workers of 91 Countries: A multicenter cross-sectional study.

The aim of this study was to investigate the COVID-19 vaccination acceptance rate and its determinants among healthcare workers in a multicenter study. This was a cross-sectional multi-center survey conducted from February 5 to April 29, 2021. The questionnaire consisted of 26 items in 6 subscales. The English version of the questionnaire was translated into seven languages and distributed through Google Forms using snowball sampling; a colleague in each country was responsible for the forward and backward translation, and also the distribution of the questionnaire. A forward stepwise logistic regression was utilized to explore the variables and questionnaire factors tied to the intention to COVID-19 vaccination. 4630 participants from 91 countries completed the questionnaire. According to the United Nations Development Program 2020, 43.6 % of participants were from low Human Development Index (HDI) regions, 48.3 % high and very high, and 8.1 % from medium. The overall vaccination hesitancy rate was 37 %. Three out of six factors of the questionnaire were significantly related to intention to the vaccination. While 'Perceived benefits of the COVID-19 vaccination' (OR: 3.82, p-value<0.001) and 'Prosocial norms' (OR: 5.18, p-value<0.001) were associated with vaccination acceptance, 'The vaccine safety/cost concerns' with OR: 3.52, p-value<0.001 was tied to vaccination hesitancy. Medical doctors and pharmacists were more willing to take the vaccine in comparison to others. Importantly, HDI with OR: 12.28, 95 % CI: 6.10-24.72 was a strong positive determinant of COVID-19 vaccination acceptance. This study highlighted the vaccination hesitancy rate of 37 % in our sample among HCWs. Increasing awareness regarding vaccination benefits, confronting the misinformation, and strengthening the prosocial norms would be the primary domains for maximizing the vaccination coverage. The study also showed that the HDI is strongly associated with the vaccination acceptance/hesitancy, in a way that those living in low HDI contexts are more hesitant to receive the vaccine.

Ceftolozane-tazobactam vs. colistin for the treatment of infections due to multidrug-resistant Pseudomonas aeruginosa: a multicentre cohort study.

OBJECTIVES: The aim of this study was to compare the safety and effectiveness of ceftolozane-tazobactam (C-T) to colistin-based regimen for treating infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa. METHODS: This was a retrospective, multicentre, observational cohort study of inpatients who received either C-T or intravenous colistin for treating infections caused by MDR P. aeruginosa. The study was conducted in five tertiary care hospitals in Saudi Arabia. The main study outcomes included clinical cure at end of treatment, in-hospital mortality, and acute kidney injury (AKI). Univariate analysis and multivariate logistic regression model were conducted to evaluate the independent effect of C-T on the clinical outcome. RESULTS: A total of 184 patients were included in the study: 82 patients received C-T, and 102 patients received colistin-based regimen. Clinical cure (77% vs. 57%; P = 0.005; OR, 2.52; 95% CI, 1.32-4.79) was significantly more common in patients who received C-T. After adjusting the difference between the two groups, treatment with C-T is independently associated with clinical cure (adjusted OR, 2.47; 95% CI, 1.16-5.27). In-hospital mortality (39% vs. 49%; P = 0.175; OR, 0.67; 95% CI, 0.37-1.20) was lower in patients who received C-T, but the difference was not significant. AKI (15% vs. 41%; P < 0.001; OR, 0.25; 95% CI, 0.12-0.51) was significantly less common in patients who received C-T. CONCLUSION: C-T is associated with a higher rate of clinical cure and lower rate of AKI compared to colistin. Our findings support the preferential use of C-T over colistin-based regimen for treating these infections.

Tocilizumab and Systemic Corticosteroids in the Management of Patients with COVID-19: A Systematic Review and Meta-Analysis.

BACKGROUND: To date, there is no effective treatment for the new coronavirus disease (COVID-19). We aimed to systematically review the literature on the association between the combination of tocilizumab (TCZ) and systemic corticosteroid therapy (SCT) on outcomes of COVID-19 patients. METHODS: We searched MEDLINE, Cochrane Central, and preprints, for studies in which health outcomes were compared between adults with severe COVID-19 who received TCZ and SCT and those who received standard of care without TCZ. Record screening, data extraction, and risk of bias assessment were performed in duplicate. Random effect models were used when pooling crude numbers and adjusted effect estimates of study outcomes. RESULTS: Our search identified seventeen studies. The pooled crude mortality rate was lower in the combination arm (relative risk, RR=0.62, 95% confidence interval [CI]=0.42 - 0.91; I2=60%). The adjusted mortality rates were also lower in the combination arm (RR=0.58, 95% CI=0.42 - 0.81; I2=71%). The rate of superinfections did not differ between the two interventions. CONCLUSIONS: The findings of this study show that combination of TCZ and SCT compared to SOC has lower mortality rates. There is an urgent need for well-designed randomized trials to assess the safety and efficacy of this combination in subjects with severe COVID-19.

Successful Use of Rifamycin-Sparing Regimens for the Treatment of Active Tuberculosis in Lung Transplant Recipients.

OBJECTIVES: Tuberculosis is an important opportunist infection that can complicate the posttransplant course of solid-organ transplant recipients. Lung transplant recipients are at higher risk of tuberculosis after transplant than are other solid-organ transplant recipients. Significant drug-drug interactions between antituberculous medications, especially rifampin, and immunosuppressant medications render treatment in this patient population especially challenging. Data on the management of tuberculosis in lung transplant recipients with rifamycin-sparing regimens are so far limited. Therefore, we evaluated the incidence, clinical features, treatment, and outcomes of active tuberculosis in lung transplant patients from a single center in Riyadh, Saudi Arabia. MATERIALS AND METHODS: Cases of active tuberculosis in lung transplant recipients diagnosed between January 2005 and December 2017 at our center were included. Data on patient demographics, clinical presentations, diagnosis, treatment regimens, and outcomes were collected. RESULTS: Seven of 133 lung transplant recipients (5.3%) were diagnosed with active tuberculosis during the study period, corresponding to an incidence rate of 2147/100 000 person-years. Patients were diagnosed at median time of 94 days posttransplant. Fever and weight loss were the most common presenting symptoms. All patients were initially treated with a regimen consisting of isoniazid, ethambutol, pyrazinamide, and moxifloxacin. Isoniazid was later substituted with rifabutin in 2 patients with isoniazid-resistant tuberculosis. All patients were treated for a total of 9 to 12 months, without any adverse event-related interruptions. All patients were alive at 12 months after the diagnosis of tuberculosis. There was no evidence of relapse in any of the patients after a median of 32 (range, 9-51) months of follow-up after treatment. CONCLUSIONS: Rifamycin-sparing regimens appear to be safe and highly efficacious in the treatment of active tuberculosis in lung transplant recipients.

Hydroxychloroquine Safety Outcome within Approved Therapeutic Protocol for COVID-19 Outpatients in Saudi Arabia.

BACKGROUND: Global healthcare is challenged following the COVID-19 pandemic, since late 2019. Multiple approaches have been performed to relieve the pressure and support existing healthcare. The Saudi Arabian Ministry of Health (MOH) launched an initiative to support the National Healthcare System. Since the 5th of June 2020, 238 outpatient fever clinics were established nationwide. This study aimed to assess the safety outcome and reported adverse events from hydroxychloroquine use among suspected COVID-19 patients. METHOD: A cross-sectional study included 2,733 patients subjected to MOH treatment protocol (hydroxychloroquine) and followed-up within 3-7 days after initiation. Data was collected through an electronic link and cross-checked with the national database (Health Electronic Surveillance Network, HESN) and reports from the MOH Morbidity and Mortality (M&M) Committee. RESULTS: 240 patients (8.8%) discontinued treatment because of side effects (4.1%) and for non-clinical reasons in the remaining (4.7%). Adverse effects were reported among (6.7%) of all studied participants, including mainly cardiovascular (2.5%, 0.15% with QTc prolongation), and gastrointestinal (2.4%). No Intensive Care Unit admission or death were reported among these patients. CONCLUSION: Our results show that hydroxychloroquine for COVID-19 patients in mild to moderate cases in an outpatient setting, within the protocol recommendation and inclusion/exclusion criteria, is safe, highly tolerable, and with minimum side effects.

Safety and tolerability of moxifloxacin for the treatment of disseminated BCGitis in children.

BACKGROUND AND OBJECTIVE: Disseminated BCGitis is a rare but serious complication of BCG vaccine in patients with underlying primary immunodeficiency. Fluoroquinolone antibiotics containing antimycobacterial regimen have been considered in the treatment of disseminated BCGitis, but there are limited data about the dosing, safety, and tolerability of fluoroquinolone such as moxifloxacin in children. The aim of this study was to report the experience with the dosing, safety, and tolerability of moxifloxacin in children with disseminated BCGitis. METHOD: This retrospective descriptive study included children who had been diagnosed with disseminated BCGitis and treated with an antimycobacterial regimen including moxifloxacin for more than two weeks from 2007 to 2017 at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. RESULT: Ten children were included: six (60.0%) were male and four (40.0%) were female. The primary diagnosis for five patients was Mendelian susceptibility to mycobacterial diseases (MSMD), four patients were diagnosed with severe combined immune deficiency (SCID), and the remaining patient had human immunodeficiency virus (HIV) infection. The overall mean duration of moxifloxacin treatment was 10.1 months. Liver toxicity was recorded in three patients. The most common medications used with moxifloxacin were ethambutol and clarithromycin. Moxifloxacin serum concentration level was determined in 5 patients. No musculoskeletal side effects were reported while the patient was on moxifloxacin. The treated patients showed a different response to an antimycobacterial regimen including moxifloxacin, with mortality in two patients. CONCLUSION: Our study suggests that moxifloxacin is generally tolerated in children and might be considered in disseminated BCGitis cases. Additionally, paying attention to side effects such as liver toxicity is recommended, particularly with the use of other antimycobacterial antibiotics, which could also be hepatotoxic. A moxifloxacin-containing regimen for disseminated BCGitis showed clinical improvement in some patients in this study, although the majority presented the same clinical condition.

Snake venom preparation for drug-resistant human immunodeficiency virus.

Resistance of human immunodeficiency virus to antiretroviral therapy is a major concern. As new therapies are few, progress to acquired immune deficiency syndrome will ensue. We report a patient with multidrug-resistant HIV, high viral load, and low CD4 count who took a snake venom preparation while maintained on antiretroviral therapy. The response was impressive with a decreased viral load and increased CD4 count that was maintained for one year.

Hypotension following treatment with aerosolized colistin in a patient with multidrug-resistant Pseudomonas aeruginosa.

OBJECTIVE: To report a case of a man who developed temporary hypotension after aerosolized colistin administration. CASE SUMMARY: A 62-year-old Arab male was admitted to the intensive care unit for respiratory failure and septic shock. Simultaneous therapy using intravenous and aerosolized colistin was initiated for the management of multidrug-resistant Pseudomonas aeruginosa. A significant but transient drop in blood pressure occurred when aerosolized colistin was introduced. However, when it was stopped, but intravenous administration was continued, no hypotension was observed. Moreover, the combined use of aerosolized amikacin with intravenous colistin did not significantly affect blood pressure. DISCUSSION: It is widely accepted that aerosolization allows safe administration of colistin in the absence of significant systemic adverse effects. However, in our patient, hypotension was observed with aerosolized colistin, but not with the systemic formulation. The lack of adverse effects with administration of aerosolized amikacin in this patient demonstrates the safety of the aerosolization technique. Use of the Naranjo scale indicated a probable relationship between hypotension and aerosolized colistin administration. CONCLUSIONS: This case suggests that hypotension may be induced with administration of aerosolized colistin. Although this effect is rare, clinicians should be aware that hypotension may develop in critically ill patients following aerosolized colistin treatment.