Search Results (886)

Background/Objectives: Escherichia coli bacteremia is a major cause of morbidity, mortality, and healthcare expenditure. The increasing prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) complicates management and resource utilization. This study aimed to identify clinical predictors of higher hospital costs in E. coli bacteremia. Methods: We conducted a cross-sectional study of hospitalized patients with E. coli bacteremia in Surabaya, Indonesia (2022–2024). Hospital costs were categorized into bed costs, diagnostic costs, pharmacy costs, antibiotic costs, total costs, and daily costs. Costs were compared between ESBL and non-ESBL cases. Predictors of higher hospital costs were analyzed using generalized linear models with a Gamma distribution and log-link. Results: Among 209 patients, 131 (62.7%) had ESBL-producing E. coli. ESBL E. coli bacteremia was associated with significantly higher bed, diagnostic, pharmacy, total, and daily hospital costs than non-ESBL cases, while antibiotic costs were similar. ESBL E. coli bacteremia was associated with higher diagnostic and daily costs. High-care/ICU stay was the strongest predictor of increased costs. Pneumonia and infection source influenced cost components. Longer hospitalization increased total cost but reduced daily cost. Conclusions: Hospital costs in Escherichia coli bacteremia are driven by antimicrobial resistance, disease severity, and healthcare utilization. Targeted strategies such as antimicrobial stewardship and optimized critical care use are essential to reduce the economic burden. Full article

Background: Vancomycin-resistant Enterococcus (VRE) bacteremia represents a major therapeutic and epidemiological challenge, particularly in regions with high antimicrobial resistance rates such as Southern Europe. Longitudinal local data are essential to guide infection control and antimicrobial stewardship strategies. This study aimed to evaluate temporal trends in incidence, management, and mortality of VRE bacteremia in a tertiary care center in Greece over a six-year period, including comparison before and after the coronavirus disease 2019 (COVID-19) pandemic. Methods: This retrospective observational study included adult patients with VRE bacteremia at the University Hospital of Heraklion, Greece, from 2018 to 2023. Demographic and clinical data, such as the Pitt Bacteremia Index (PBI), as well as microbiological, and treatment data were collected from patient records. Incidence was calculated per 10,000 patient-days. Comparisons were performed between survivors and non-survivors and between pre- and post-COVID-19 eras. Multivariate regression analysis was used to identify predictors of in-hospital mortality. Results: A total of 96 patients were included (mean age 68.6 ± 14.5 years; 56.3% male). The incidence of VRE bacteremia increased more than five-fold during the study period, from 0.242 cases per 10,000 patient-days in 2018 to a peak of 1.344 per 10,000 patient-days in 2022, remaining elevated in 2023 (1.001 per 10,000 patient-days). The overall in-hospital mortality was 54.2%. Non-survivors had significantly higher PBI scores compared to survivors (median 2.5 vs. 0, p = 0.005). In the multivariate analysis, higher PBI was independently associated with in-hospital mortality [odds ratio: 1.449 (95% confidence intervals: 1.166–1.801)]. Appropriate empirical therapy was administered in 41.7% of cases and was not significantly associated with survival. Post-COVID-19 patients were older (69.9 vs. 61.4 years, p = 0.0365), and antimicrobial regimens were more frequently adjusted according to susceptibility testing (55.7% vs. 18.2%, p = 0.0141), but mortality did not significantly differ between periods. Conclusion: VRE bacteremia incidence increased dramatically over the six-year study period in our tertiary center, with persistently high mortality exceeding 50%. Severity of illness at the diagnosis of bacteremia, as measured by the PBI, was an independent predictor of in-hospital mortality. Strengthened infection prevention measures, optimized antimicrobial stewardship, and early aggressive management are urgently needed to mitigate the growing burden of VRE bacteremia. Full article

Background: Venous catheter placement is the most common invasive procedure performed in hospitals. Despite their widespread use and importance in healthcare, these devices can cause complications such as catheter-associated bloodstream infections (CABSIs). Although several studies have investigated potential risk factors, including sociodemographic, medical history, and clinical variables, the results remain inconsistent and inconclusive. Objectives: The aim of this study was to identify independent risk factors for CABSIs and to develop and validate a predictive model for CABSIs in patients with midline catheters, centrally inserted central catheters (CICCs), and peripherally inserted central catheters (PICCs). Methods: We conducted an observational cohort follow-up study including hospitalized patients with a CICC, PICC, or midline catheter between January 2016 and March 2022. Devices were randomly assigned to derivation (n = 6036) and validation (n = 1549) cohorts. Candidate predictors with p < 0.25 in univariate analysis entered a multivariable logistic regression model, and final variables were selected by backward stepwise regression. Performance in the validation cohort was assessed by calibration and discrimination using the Hosmer–Lemeshow test and AUC. Results: The prevalence of CABSIs in the derivation cohort was 1.8%. Independent risk factors for CABSIs included tracheostomy, a history of bacteremia within 3 months before catheter placement, the presence of a synchronous central catheter, active oncohematological disease, and having received total parenteral nutrition (TPN). The presence of these five variables increased the probability of CABSIs to 42.1%. The final model demonstrated good predictive performance with an area under the curve (AUC) of 0.73 in the derivation cohort and 0.77 in the validation cohort. Decision curve analysis showed that the predictive model offered a greater net clinical benefit than the “treat-all” or “treat-none” strategies among threshold probabilities between 0.5% and 5%. Conclusions: The model can help identify high-risk patients, guide risk-based clinical decisions, reduce unnecessary catheter use, and support infection prevention and antimicrobial stewardship. Full article

Background/Objectives: Infections caused by multidrug-resistant Gram-negative bacteria (MDR-GNB) represent a major therapeutic challenge, particularly in hospitalized and critically ill patients with limited treatment options. Cefiderocol, a novel siderophore cephalosporin, has demonstrated activity against a broad range of resistant Gram-negative pathogens. We aimed to evaluate the effectiveness and safety of cefiderocol for the treatment of MDR-GNB infection. Methods: We conducted a retrospective observational study including all adult patients who received ≥72 h of cefiderocol between November 2020 and October 2024 at a Spanish tertiary-care hospital. The primary outcome was clinical success, defined as survival and absence of clinical recurrence 30 days after cefiderocol initiation. Secondary outcomes included 30- and 90-day mortality, clinical and microbiological recurrence, emergence of resistance, and adverse events. Results: Eighty patients were included (median age 64 years [IQR 56–72]; 81.3% male). Respiratory (26.2%) and abdominal (22.5%) infections were the most common, and 20% presented with bacteremia. At infection onset, 26.2% had septic shock and 45% required intensive care unit admission. The three most frequently isolated pathogen was Pseudomonas aeruginosa (33.9%), followed by Enterobacterales (33%) and Stenotrophomonas maltophilia (30.1%). Clinical success was achieved in 67.5% of patients. Thirty and 90-day mortality rates were 27.5% and 36.5%, respectively. Recurrence within 90 days occurred in 5% of cases. Emergence of resistance was detected in one Klebsiella pneumoniae ST147 isolate, and serious adverse events occurred in 5% of patients. Conclusions: In a cohort including a substantial proportion of critically ill patients, cefiderocol was associated with favorable clinical outcomes and an acceptable safety profile. These findings suggest that cefiderocol may represent a useful therapeutic option for severe MDR-GNB infections in patients with limited treatment alternatives. Full article

Background: The global demographic shift towards an aging population has driven a steady, exponential increase in the utilization of cardiac implantable electronic devices (CIEDs). Consequently, device-related infectious complications have emerged as a leading cause of morbidity and healthcare expenditure. Patients in their eighth decade of life—octogenarians (aged 80–90 years)—represent an exceptionally high-risk demographic due to the compounding factors of physiological frailty, immunosenescence, and complex multi-morbidity. Despite this growing demographic, their specific clinical presentations, microbiological profiles, and procedural outcomes following infection remain poorly defined in the current literature. This study aimed to comprehensively compare the clinical characteristics, pathogen distribution, and in-hospital outcomes of CIED infections in an octogenarian cohort against a younger patient population. Methods: We conducted a robust retrospective cohort analysis of 383 consecutive patients treated for confirmed CIED infections at one major tertiary referral center (Heidelberg University Hospital) between January 2002 and December 2022. The cohort was stratified by age into octogenarians (n = 76) and a younger control group (n = 307). We systematically extracted and compared data regarding baseline clinical presentation, chronic comorbidities, detailed microbiological cultures (pocket, blood, and extracted leads), and definitive in-hospital outcomes, primarily mortality and length of stay. Results: The octogenarian cohort exhibited a significantly heavier comorbidity burden, notably higher rates of coronary artery disease (51.3% vs. 29.6%, p < 0.001), systemic hypertension (55.3% vs. 38.1%, p = 0.007), and chronic obstructive pulmonary disease (7.9% vs. 1.6%, p = 0.003). Furthermore, therapeutic systemic anticoagulant use was substantially more prevalent in the elderly group (60.5% vs. 45.0%, p = 0.015). Octogenarians presented overwhelmingly with localized generator pocket infections (73.0% vs. 30.0%, p < 0.001) but paradoxically also demonstrated higher rates of systemic bacteremia and sepsis (26.3% vs. 15.0%, p = 0.019). Microbiological analysis revealed a unique pathogen profile, with Staphylococcus capitis found with significantly higher frequency in the generator pockets of the elderly cohort. Remarkably, despite possessing a higher average lead burden (2.1 vs. 1.2 leads) and extreme comorbidity profiles, octogenarians demonstrated no statistically significant differences in in-hospital mortality (3.9% vs. 4.2%, p = 1.000) or overall length of hospital stay (14.7 vs. 17.2 days, p = 0.386) when compared to the younger cohort. Conclusions: Octogenarians suffering from CIED infections display highly distinct clinical and microbiological profiles, characterized predominantly by elevated rates of localized pocket infections, specific opportunistic pathogens, and a severe underlying comorbidity burden. Crucially, our findings indicate that with the application of modern extraction and management protocols, advanced age alone does not intrinsically correlate with increased in-hospital mortality. Future prevention and perioperative management strategies tailored to this rapidly expanding demographic must heavily prioritize the mitigation of pocket-related complications, particularly considering the high prevalence of concurrent anticoagulation therapy. Full article

Pasteurella species are facultatively anaerobic Gram-negative coccobacilli residing in the upper respiratory tract of mammals, fowl and domestic animals including cats and dogs. Localized infections with Pasteurella species are common but invasive infections are rare. There is a paucity of data available on risk factors, clinical presentations and outcomes with Pasteurella bloodstream infection. We conducted a retrospective review of patients with Pasteurella bacteremia presenting to our institution. There were 63 presentations (61 patients) with Pasteurella bacteremia. Immunosuppression, malignancy and alcohol misuse were common. Rates of admission to intensive care (n = 18, 29.5%) and death prior to hospital discharge (n = 7, 11.5%) were high. Full article

Background: Blood cultures are frequently obtained in the emergency department (ED), yet organism identification and subsequent antibiotic optimization commonly occur after hospital admission. Inappropriate empiric therapy remains common and is associated with adverse outcomes. MALDI-TOF MS can shorten the time to organism identification; however, real-world effectiveness may depend on laboratory cadence and stewardship support, and evidence for once-daily batch workflows without active antimicrobial stewardship is limited. Method: We performed a retrospective before–after cohort study at a tertiary medical center in central Taiwan, comparing positive blood cultures (PBCs) obtained in the ED before MALDI-TOF MS implementation (1 May–31 July 2018; conventional identification) and after implementation (1 September–30 November 2018; MALDI-TOF MS). Primary endpoints were appropriate antibiotic therapy at 24, 48, and 72 h after the first PBC report. Secondary endpoints included timing, location, and classification (escalation vs. de-escalation) of the first antibiotic modification. Results: After exclusions, 323 unique PBCs were analyzed (182 pre-implementation; 141 post-implementation). Baseline characteristics and clinical outcomes were similar, including in-hospital mortality (14.8% vs. 14.9%). Time to the initial positive report (Gram stain) and the final report (identification with antimicrobial susceptibility testing) did not differ significantly between periods. Appropriate antibiotic use at 24/48/72 h was comparable (75.3% vs. 76.6%, 82.4% vs. 80.1%, and 86.3% vs. 84.4%). The timing and pattern of the first antibiotic modification were also similar. In a secondary stratified analysis, patients modified before culture positivity had higher acuity and worse outcomes. Conclusions: Once-daily MALDI-TOF MS implementation was not associated with improved antibiotic appropriateness or modification patterns in ED bacteremia without active real-time stewardship oversight. Higher-frequency processing and real-time stewardship linkage may be required to translate faster diagnostics into timely therapeutic action. Full article

Background: Late-onset anaerobic prosthetic joint infection (PJI) is uncommon but may indicate underlying, previously asymptomatic colorectal malignancy. While the association between Streptococcus bovis group (SBG) bacteremia and colorectal cancer is well established, links between anaerobic PJIs and colorectal neoplasia are rarely reported. Anaerobic organisms originating from the gastrointestinal tract may translocate via the hematogenous route, and their presence in PJI should prompt clinicians to consider occult colorectal pathology. Methods: All periprosthetic arthroplasty infection cases between 2015 and 2025 were reviewed. Clinical records, diagnostic findings, microbiological data, and treatment outcomes were analyzed. Results: Three female patients (mean age 76.3 years) presented with late-onset PJI occurring at least five years after primary total knee arthroplasty. Causative organisms included Bacteroides fragilis, Morganella morganii, and Klebsiella pneumoniae. All patients underwent two single-stage revision surgeries and one debridement, antibiotics and implant retention (DAIR) procedure. Cross-sectional computed tomography imaging of the abdomen and pelvis (CT-AP) performed to evaluate hematogenous sources of infection consistently revealed previously undiagnosed colorectal malignancy. One patient had additional metastatic disease. Postoperative complications included one case of pulmonary embolism; no other major complications were observed. Conclusions: Anaerobic PJIs are rare, and their association with colorectal malignancy is not well established. These cases highlight the importance of evaluating potential gastrointestinal sources, including occult colorectal cancer, in patients presenting with late-onset anaerobic PJI. Full article

Background: The genus Brucella has expanded considerably in the 21st century. With the advent of advanced phylogenetic analyses, a close genetic relationship between Brucella and Ochrobactrum has been identified, leading to reclassification of Ochrobactrum species within the genus Brucella. Among these, Brucella anthropi (formerly Ochrobactrum anthropi) is increasingly recognized as a rare cause of invasive human infection. We report a clinically significant case of B. anthropi infective endocarditis and review the available literature. Methods: We report a case of B. anthropi infective endocarditis and conducted a narrative review of the English-language medical literature through 2025. Cases were analyzed for demographics, clinical presentation, antimicrobial susceptibility, and outcomes. Results: A 75-year-old man with a prosthetic aortic valve and prior endocarditis presented with fever of unknown origin, weight loss, and prior transient ischemic attacks. Blood cultures grew B. anthropi after prolonged incubation. Transesophageal echocardiography demonstrated vegetations involving both the aortic and tricuspid valves, and the patient required targeted combination antimicrobial therapy due to persistent bacteremia. Seven additional cases of B. anthropi infective endocarditis were identified on review of the literature. Most patients had underlying valvular disease or prosthetic material. Reported lethality approached 25%. Antimicrobial susceptibility patterns were variable, underscoring the importance of targeted individualized therapy. Conclusion: Consistent with other Gram-negative bacilli, B. anthropi is a rare but established cause of acute bacterial endocarditis. Despite its rarity, it may represent an under-recognized cause of invasive disease. This case highlights the importance of prolonged culture incubation, careful microbiologic interpretation, and susceptibility-guided therapy. Full article

Background: Ceftobiprole is an advanced-generation cephalosporin approved in Europe in 2013 for various indications, and in the United States (US) in 2024 for community-acquired bacterial pneumonia (CABP), acute bacterial skin and skin structure infections, and Staphylococcus aureus bacteremia, including right-sided endocarditis. Methods: The in vitro activity of ceftobiprole and comparators was evaluated against 2793 Streptococcus pneumoniae causing lower respiratory tract infections in 32 US sites (2016–2020), including against subsets from various geographic regions, resistance phenotypes and prevalent serotypes. Results: Ceftobiprole inhibited 99.5% of all S. pneumoniae at the MIC of ≤0.5 mg/L (MIC_50/90, 0.015/0.25 mg/L). Susceptibilities of 98.2% to 100% were observed for ceftobiprole against isolates originating from each surveyed year or each US Census Division. Ceftobiprole retained activity against isolates resistant to macrolides (98.8%), tetracycline (98.2%), oral penicillin (95.4%), against multidrug-resistant isolates (97.0%), and various serotypes (93.8–100%). Ceftriaxone (97.4%) and amoxicillin–clavulanate (95.1%) also showed elevated susceptibilities overall, but inconsistent results and lower than those observed for ceftobiprole were noted against isolates with elevated penicillin MIC or specific serotypes (i.e., 19A). Conclusions: These in vitro results, coupled with documented clinical efficacy, indicate that ceftobiprole is a valuable option to treat CABP caused by S. pneumoniae in the US. Full article

Background/Objectives: Non-typhoidal Salmonella (NTS) species are well-recognized causes of invasive infection in patients with sickle cell disease (SCD), with a particular predilection for the musculoskeletal system. Although Salmonella osteomyelitis is well described in this population, septic arthritis is uncommon, especially involving the shoulder joint. We describe a case of NTS bacteremia complicated by native shoulder septic arthritis in a patient with SCD and review its clinical implications. Methods: We report the clinical course, diagnostic evaluation, microbiologic findings, imaging studies, and management of a 22-year-old man with homozygous SCD who presented with a vaso-occlusive pain crisis and subsequently developed severe sepsis with persistent Salmonella enterica bacteremia following ingestion of undercooked poultry. Persistent bacteremia prompted further evaluation for metastatic infection using advanced imaging and diagnostic arthrocentesis. Results: Whole-body imaging identified septic arthritis of the native right shoulder, which was confirmed by synovial fluid cultures growing Salmonella species. The patient underwent arthroscopic irrigation and debridement for source control. Antimicrobial therapy was narrowed to intravenous ceftriaxone based on susceptibility data and continued for six weeks. The patient demonstrated clinical improvement with resolution of bacteremia and was discharged to rehabilitation to complete therapy. Conclusions: This case highlights the importance of a careful exposure history, including foodborne sources, in patients with SCD presenting with invasive Salmonella infection. Persistent bacteremia should prompt early investigation for metastatic foci, and timely surgical source control combined with targeted antimicrobial therapy is essential for optimal outcomes in this population. Full article

Background: Staphylococcus aureus bloodstream infections cause substantial hospital mortality (20–50%). Surveillance programs primarily focus on methicillin-resistant S. aureus (MRSA) as a quality indicator, while comprehensive data comparing MRSA and methicillin-susceptible S. aureus (MSSA) hospital-onset bacteremia remain limited outside the UK, the USA, and Canada. This study aims to evaluate incidence trends of all hospital-onset S. aureus bloodstream infections (HO-SABSIs, defined as positive blood cultures ≥ 48 h post-admission) from 2013 onwards, comparing MRSA and MSSA incidence patterns and their associated mortality rates in an Italian tertiary-care hospital through surveillance data. Methods: Retrospective cohort study of all HO-SABSIs from January 2013 to December 2023 at a 458-bed Italian tertiary hospital. Primary outcome was incidence density (cases per 1000 patient-days) stratified by methicillin resistance. Standardized Infection Ratios (SIRs) were calculated using 2013–2015 and 2013–2019 as baseline periods. Temporal trends were analyzed using negative binomial regression. Results: Among 414 HO-SABSI cases, 183 (44.2%) were MRSA and 231 (55.8%) MSSA. MRSA incidence decreased significantly (−6.5% annually; IRR 0.935, 95%CI 0.883–0.991; p = 0.023) from 0.198 to 0.111 per 1000 patient-days. MSSA increased non-significantly (+4.9% annually; IRR 1.049, 95%CI 0.999–1.103; p = 0.056) from 0.103 to 0.239, surpassing MRSA after 2016 and peaking during COVID-19 (2021: SIR 2.41, 95%CI 1.33–4.37). MRSA cases had higher mortality than MSSA (40.6% vs. 27.5%; p = 0.005). Conclusions: MSSA has replaced MRSA as the predominant hospital-onset S. aureus bacteremia pathogen since 2016, with sustained elevation during and after the COVID-19 pandemic. Current MRSA-focused surveillance misses the majority of preventable staphylococcal bacteremias. Comprehensive hospital-onset S. aureus surveillance encompassing both phenotypes is essential for accurate epidemiological assessment and infection prevention. Full article

Stenotrophomonas maltophilia bacteremia is an opportunistic infection associated with high mortality among intensive care unit (ICU) patients, largely due to intrinsic antimicrobial resistance and the severe underlying conditions of affected hosts. This study aimed to identify independent predictors of 28-day mortality, evaluate the prognostic value of laboratory biomarkers, and assess the impact of source control in ICU patients with S. maltophilia bacteremia. A retrospective single-center case–control study was conducted over a five-year period, including 148 ICU patients with S. maltophilia bacteremia and 1:1 matched non-S. maltophilia controls. Demographic, clinical, and laboratory data were analyzed using multivariate logistic regression to determine independent predictors of mortality, while receiver operating characteristic (ROC) analysis assessed the prognostic performance of selected biomarkers. Multivariate analysis identified shock (OR = 6.01; 95% CI: 3.13–11.56; p < 0.001), underlying malignancy (OR = 4.31; 95% CI: 1.44–12.96; p = 0.009), higher Sequential Organ Failure Assessment (SOFA) score (OR = 1.28; 95% CI: 1.16–1.41; p < 0.001), and elevated procalcitonin levels (OR = 1.014; 95% CI: 1.002–1.026; p = 0.019) as independent predictors of mortality. A multivariable prediction model incorporating age, SOFA score, shock, malignancy, procalcitonin, and lactate demonstrated good discriminative performance for predicting 28-day mortality (AUC = 0.817; p < 0.001). Source control was significantly associated with improved survival. These findings suggest that hemodynamic instability, malignancy, and severe organ dysfunction are major determinants of mortality in ICU patients with S. maltophilia bacteremia, and that multidimensional risk assessment models integrating clinical severity scores and biomarkers may facilitate early identification of high-risk patients and support targeted clinical management. Full article

Background: We aimed to describe the clinical and microbiological characteristics of biliary-source bloodstream infections (bBSIs) in patients with malignancies and identify risk factors for recurrence. Methods: All bBSI episodes in patients with active solid tumors during 2021–2025 were retrospectively reviewed. Independent risk factors for recurrent bBSI and mortality were identified. A previously published recurrence risk score was externally validated. Results: Overall, 136 patients experienced 199 bBSI episodes. Pancreatic (36.7%) and biliary tract (33.2%) were the most common cancers, and 60.8% had metastatic disease. The main pathogens were Escherichia coli (43.2%), Klebsiella pneumoniae (24.1%), and Enterococcus faecium (19.1%), and multidrug-resistant organisms accounted for 19.1%. Inappropriate empirical antibiotic treatment (IEAT) occurred in 37.2% and was independently associated with increased 30-day mortality, together with metastatic disease and septic shock. Thirty-day mortality was 24.6%. Recurrent bBSI occurred in 35.7% and was independently associated with biliary tract cancer, previous multidrug-resistant isolation, and prior hospitalization for suspected biliary infection. The externally validated recurrence score showed excellent discrimination (AUC 0.815). Conclusions: bBSI in oncology patients is associated with high rates of MDR pathogens, IEAT, recurrence, and mortality. A simple clinical score may identify patients at high risk of recurrence and guide preventive strategies. Full article

Background: Rapidly progressive glomerulonephritis (RPGN) is a severe nephrological emergency, frequently secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. In older adults, the coexistence of comorbidities and monoclonal gammopathy of undetermined significance (MGUS) makes it difficult to distinguish between ANCA vasculitis and monoclonal gammopathy of renal significance (MGRS), which differ in prognosis and treatment. The coexistence of PR3-ANCA-associated vasculitis and MGUS is uncommon and sparsely documented. Case Presentation: A 72-year-old woman with hypertension and type 2 diabetes presented with acute deterioration and rapidly progressive renal failure, requiring hemodialysis. She had subnephrotic proteinuria, hematuria, and an active urinary sediment. The autoimmune workup showed ANCA negativity using immunofluorescence, but PR3-ANCA positivity using ELISA. Hematologic characterization documented an IgG kappa monoclonal spike; no bone lesions, amyloidosis, or criteria for multiple myeloma were found; and the patient was classified as MGUS. Renal biopsy revealed necrotizing extracapillary pauci-immune glomerulonephritis with cellular and fibrocellular crescents and no monoclonal deposits, consistent with PR3-ANCA vasculitis. Induction therapy with methylprednisolone pulses and oral prednisone was initiated; cyclophosphamide was not administered because of catheter-associated Staphylococcus aureus bacteremia and upper gastrointestinal bleeding complicated by disseminated intravascular coagulation. The patient died on day 25 due to infectious and hemorrhagic complications. Conclusions: This case provides additional documentation of an uncommon overlap between PR3-ANCA-associated vasculitis and MGUS in a Latin American patient and highlights the role of renal biopsy in distinguishing MGRS from pauci-immune vasculitis in the presence of paraproteinemia. It also underscores the need to tailor immunosuppression in frail older adults, balancing disease control against the risk of severe infection. Full article