Background: Infections caused by multidrug-resistant/difficult-to-treat (MDR/DTR) Pseudomonas aeruginosa present a significant challenge for treatment. Ceftolozane–tazobactam (C/T) and ceftazidime–avibactam (C/A) are important options that combine β-lactam and β-lactamase inhibitors, but their effectiveness compared to each other is still unclear. Methods: We performed a systematic review and meta-analysis, evaluated by Grading of Recommendations Assessment, Development, and Evaluation (GRADE), of comparative observational studies that included hospitalized adults with confirmed MDR/DTR P. aeruginosa infections up to 10 October 2025 (English only). Studies comparing C/T directly with C/A and matched therapies were included. We used random-effects Mantel–Haenszel models to calculate pooled risk ratios (RR) with 95% confidence intervals (CIs), and we assessed heterogeneity with I ² . We reviewed the certainty of evidence using GRADE. Results: Six observational cohorts ( n = 1161) met our criteria. There were no significant differences between C/T and C/A for clinical success (RR: 1.07, 0.89–1.29; I ² = 40%), 30-day all-cause mortality (RR: 1.02, 95% CI: 0.83–1.27; I ² = 0%), 30-day recurrence (RR: 0.85, 0.46–1.57; I ² = 48%), 90-day recurrence (RR: 0.80, 0.63–1.02; I ² = 0%; P = 0.08), emergence of resistance (RR: 0.73, 0.30–1.81; I ² = 84%), and microbiological response failure (RR: 0.91, 0.66–1.26; I ² = 8%). There was a non-significant trend that slightly favored C/T for 90-day recurrence. According to GRADE, the certainty of evidence varied from low to very low, mainly due to non-randomized study designs and variability across studies. Conclusions: In current comparative cohorts, C/T and C/A show similar outcomes for severe MDR/DTR P. aeruginosa infections. More high-quality randomized trials are needed to better define any potential differences and clarify long-term recurrence and resistance risks.

Facial acne scarring is a widely prevalent dermatological disease manifested as a permanent aftereffect of acne vulgaris. While fractional CO₂ laser and needling procedures are essential to treating atrophic acne scars, comparative and safety data remains limited. This systematic review and meta-analysis directly compares their efficacy and safety. According to PRISMA guidelines, PubMed, Cochrane, Google Scholar, and ClinicalTrials.gov were systematically searched. Only studies comparing fractional CO₂ laser with needling-based monotherapy treating facial atrophic acne scars in adults were included. A random-effects model was employed for meta-analysis using Review Manager (RevMan) to compare efficacy and safety outcomes. A total of 17 studies were included in the meta-analysis. For primary efficacy outcomes, the results were non-significant for mean scar score reduction (SMD: -1.08, 95% CI: [-2.48, 0.32], I² = 97%) or mean quantitative scar reduction (SMD: 0.12, 95% CI: [-0.80, 1.04], I² = 92%), with significant heterogeneity. However, categorical treatment success was significantly high for CO₂ laser (RR: 1.10, 95% CI: [1.01, 1.20], I² = 0%). For safety outcomes, fractional CO₂ laser showed significantly high risk of post-inflammatory hyperpigmentation (PIH) as compared to standard microneedling (RR: 3.04, 95% CI: [1.49, 6.21], I² = 3%), but showed significantly low pain scores as compared to RF microneedling (SMD: -0.74, 95% CI: [-1.27, -0.21], I² = 0%). No significant differences were found for erythema, crusting/scabbing, or edema. Both fractional CO₂ laser and microneedling procedures show comparable efficacy in treating atrophic acne scars, however, patient variables such as skin type, scar type, and possible complications should be taken into consideration. Moreover, further tailored therapies are crucial to treating acne scars with low risk for complications.

Background: Substance use disorders constitute a major public health crisis in the United States. While overall stroke mortality has declined significantly, trends in stroke mortality among individuals with documented substance use are incompletely understood across demographic and geographic strata. Objective: To compare stroke mortality trends between individuals with and without documented substance use from 1999 to 2023, and to identify demographic and geographic subgroups with elevated burden. Methods: We conducted a comparative retrospective analysis using the CDC WONDER database, examining death certificates from 1999 to 2023. Deaths were identified using ICD-10 codes for stroke and substance use. Age-adjusted mortality rates (AAMRs) per 100 000 were calculated using joinpoint regression, stratified by sex, race/ethnicity, age, census region, and urban-rural status. Results: From 1999 to 2023, stroke accounted for 4 456 273 deaths (average AAMR: 82.85 per 100 000), while stroke with documented substance use resulted in 294 474 deaths (average AAMR: 5.03 per 100 000). Overall stroke AAMR declined from 129.52 to 61.77 per 100 000 (AAPC: − 3.06%, 95% CI: − 3.66% to −2.45%, P <0.001), whereas substance-related stroke AAMR increased from 1.39 to 6.83 per 100 000 (AAPC: 6.64%, 95% CI: 4.93% to 8.38%, P <0.001). Females demonstrated steeper relative increases than males (AAPC: 8.42% vs. 6.27%), with the most dramatic acceleration among older adults ≥65 years (AAPC: 7.36%). Geographic patterns revealed highest rates in Midwest and Western states, with Oregon consistently demonstrating the highest state-level rates (14.28 per 100 000 in 2021–2023). Non-metropolitan areas experienced disproportionate burden compared to metropolitan areas (11.02 vs. 6.38 per 100 000 in 2020). Conclusions: This study identified divergent mortality trends, with declining overall stroke mortality contrasted by a nearly five-fold increase in stroke deaths with documented substance use. These patterns may reflect true epidemiological changes, improved documentation practices, or both, indicating potential for integrated surveillance and targeted interventions in high-burden populations.