Sepsis mimics among presumed sepsis patients at intensive care admission: a retrospective observational study.

BACKGROUND: Diagnosing sepsis remains a challenge because of the lack of gold-standard diagnostics. Since there are no simple, broadly accepted criteria for infection, there is a risk of misclassifying sepsis patients (sepsis mimics) among patients with organ failure. The main objective of this study was to investigate the proportion of non-infected patients (sepsis mimics) in ICU patients with presumed sepsis at intensive care unit (ICU) admission. METHODS: Adult patients were screened retrospectively during 3.5 years in four ICUs in Sweden for fulfilment of the sepsis-3 criteria at ICU admission (presumed sepsis). Proxy criteria for suspected infection were sampled blood culture(s) and concomitant antibiotic administration. Culture-negative presumed sepsis patients were screened for infection according to the Linder-Mellhammar Criteria of Infection (LMCI). Sepsis mimics were defined as without probable infection according to the LMCI. Confirmed sepsis was defined as presumed sepsis after the exclusion of sepsis mimics. RESULTS: In the ICU presumed sepsis cohort (2664 patients), 25% were considered sepsis mimics. The most common reasons for ICU admission among sepsis mimics were acute heart failure and unspecific respiratory failure. Comparing sepsis mimics and confirmed sepsis showed that confirmed sepsis patients were slightly more severely ill but had similar mortality. C-reactive protein had modest discriminatory power (AUROC 0.71) with confirmed sepsis as the outcome. CONCLUSIONS: One-fourth of a presumed ICU sepsis population identified with the sepsis-3 criteria could be considered sepsis mimics. The high proportion of sepsis mimics has a potential dilutional effect on the presumed sepsis population, which threatens the validity of results from sepsis studies using recommended sepsis criteria.

Plasma glial fibrillary acidic protein and tau: predictors of neurological outcome after cardiac arrest.

BACKGROUND: The purpose was to evaluate glial fibrillary acidic protein (GFAP) and total-tau in plasma as predictors of poor neurological outcome after out-of-hospital (OHCA) and in-hospital cardiac arrest (IHCA), including comparisons with neurofilament light (NFL) and neuron-specific enolase (NSE). METHODS: Retrospective multicentre observational study of patients admitted to an intensive care unit (ICU) in three hospitals in Sweden 2014-2018. Blood samples were collected at ICU admission, 12 h, and 48 h post-cardiac arrest. Poor neurological outcome was defined as Cerebral Performance Category 3-5 at 2-6 months after cardiac arrest. Plasma samples were retrospectively analysed for GFAP, tau, and NFL. Serum NSE was analysed in clinical care. Prognostic performances were tested with the area under the receiver operating characteristics curve (AUC). RESULTS: Of the 428 included patients, 328 were OHCA, and 100 were IHCA. At ICU admission, 12 h and 48 h post-cardiac arrest, GFAP predicted neurological outcome after OHCA with AUC (95% CI) 0.76 (0.70-0.82), 0.86 (0.81-0.90) and 0.91 (0.87-0.96), and after IHCA with AUC (95% CI) 0.77 (0.66-0.87), 0.83 (0.74-0.92) and 0.83 (0.71-0.95). At the same time points, tau predicted outcome after OHCA with AUC (95% CI) 0.72 (0.66-0.79), 0.75 (0.69-0.81), and 0.93 (0.89-0.96) and after IHCA with AUC (95% CI) 0.61 (0.49-0.74), 0.68 (0.56-0.79), and 0.77 (0.65-0.90). Adding the change in biomarker levels between time points did not improve predictive accuracy compared to the last time point. In a subset of patients, GFAP at 12 h and 48 h, as well as tau at 48 h, offered similar predictive value as NSE at 48 h (the earliest time point NSE is recommended in guidelines) after both OHCA and IHCA. The predictive performance of NFL was similar or superior to GFAP and tau at all time points after OHCA and IHCA. CONCLUSION: GFAP and tau are promising biomarkers for neuroprognostication, with the highest predictive performance at 48 h after OHCA, but not superior to NFL. The predictive ability of GFAP may be sufficiently high for clinical use at 12 h after cardiac arrest.

Prolonged Fatigue and Mental Health Challenges in Critical COVID-19 Survivors.

Background: The aim of this study was to investigate the development of fatigue and mental illness between 3 and 12 months after critical COVID-19 and explore risk factors for long-lasting symptoms. Study Design and Methods: A prospective, multicenter COVID-19 study in southern Sweden, including adult patients (≥18 years) with rtPCR-confirmed COVID-19 requiring intensive care. Survivors were invited to a follow-up at 3 and 12 months, where patient-reported symptoms were assessed using the Modified Fatigue Impact Scale (MFIS), the Hospital Anxiety and Depression Scale (HADS) and the Posttraumatic Stress Disorder Checklist version 5 (PCL-5). The development between 3 and 12 months was described by changes in relation to statistical significance and suggested values for a minimally important difference (MID). Potential risk factors for long-lasting symptoms were analyzed by multivariable logistic regression. Results: At the 3-month follow-up, 262 survivors (87%) participated, 215 (72%) returned at 12 months. Fatigue was reported by 50% versus 40%, with a significant improvement at 12 months (MFIS; median 38 vs. 33, P < .001, MID ≥4). There were no significant differences in symptoms of mental illness between 3 and 12 months, with anxiety present in 33% versus 28%, depression in 30% versus 22%, and posttraumatic stress disorder in 17% versus 13%. A worse functional outcome and less sleep compared to before COVID-19 were risk factors for fatigue and mental illness at 12 months. Conclusions: Fatigue improved between 3 and 12 months but was still common. Symptoms of mental illness remained unchanged with anxiety being the most reported. A worse functional outcome and less sleep compared to before COVID-19 were identified as risk factors for reporting long-lasting symptoms.

Plasma neutrophil gelatinase-associated lipocalin independently predicts dialysis need and mortality in critical COVID-19.

Neutrophil gelatinase-associated lipocalin (NGAL) is a novel kidney injury and inflammation biomarker. We investigated whether NGAL could be used to predict continuous renal replacement therapy (CRRT) and mortality in critical coronavirus disease 2019 (COVID-19). This prospective multicenter cohort study included adult COVID-19 patients in six intensive care units (ICUs) in Sweden between May 11, 2020 and May 10, 2021. Blood was sampled at admission, days two and seven in the ICU. The samples were batch analyzed for NGAL, creatinine, and cystatin c after the end of the study period. Initiation of CRRT and 90-day survival were used as dependent variables in regression models. Of 498 included patients, 494 were analyzed regarding CRRT and 399 were analyzed regarding survival. Seventy patients received CRRT and 154 patients did not survive past 90 days. NGAL, in combination with creatinine and cystatin c, predicted the subsequent initiation of CRRT with an area under the curve (AUC) of 0.95. For mortality, NGAL, in combination with age and sex, had an AUC of 0.83. In conclusion, NGAL is a valuable biomarker for predicting subsequent initiation of CRRT and 90-day mortality in critical COVID-19. NGAL should be considered when developing future clinical scoring systems.

Long-term Mortality and Hospital Readmissions Among Survivors of Sepsis in Sweden: A Population-Based Cohort Study.

Background: Survivors of sepsis may experience long-term risk of increased morbidity and mortality, but estimations of cause-specific effects beyond 1 year after a sepsis episode are lacking. Method: This nationwide population-based cohort study linked data from national registers to compare patients aged ≥18 years in Sweden admitted to an intensive care unit from 2008 to 2019 with severe community-acquired sepsis. Patients were identified through the Swedish Intensive Care Registry, and randomly selected population controls were matched for age, sex, calendar year, and county of residence. Confounding from comorbidities, health care use, and socioeconomic and demographic factors was accounted for by using entropy-balancing methods. Long-term mortality and readmission rates, total and cause specific, were compared for 20 313 patients with sepsis and 396 976 controls via Cox regression. Results: During the total follow-up period, 56% of patients with sepsis died, as opposed to 26% of the weighted controls. The hazard ratio for all-cause mortality was attenuated with time but remained elevated in all periods: 3.0 (95% CI, 2.8-3.2) at 2 to 12 months after admission, 1.8 to 1.9 between 1 and 5 years, and 1.6 (95% CI, 1.5-1.8) at >5 years. The major causes of death and readmission among the sepsis cases were infectious diseases, cancer, and cardiovascular diseases. The hazard ratios were larger among those without underlying comorbidities. Conclusions: Severe community-acquired sepsis was associated with substantial long-term effects beyond 1 year, as measured by mortality and rehospitalization. The cause-specific rates indicate the importance of underlying or undetected comorbidities while suggesting that survivors of sepsis may face increased long-term mortality and morbidity not explained by underlying health factors.

Increasing plasma calprotectin (S100A8/A9) is associated with 12-month mortality and unfavourable functional outcome in critically ill COVID-19 patients.

BACKGROUND: Calprotectin (S100A8/A9) is a pro-inflammatory mediator primarily released from neutrophils. Previous studies have revealed associations between plasma calprotectin, disease severity and in-hospital mortality in unselected COVID-19 patients. OBJECTIVE: We aimed to assess whether plasma calprotectin dynamics during the first week of intensive care are associated with mortality and functional outcome in critically ill COVID-19 patients. METHODS: This prospective study included 498 COVID-19 patients admitted to six intensive care units (ICUs) in Sweden between May 2020 and May 2021. Blood samples were collected on ICU admission and on day 7. The primary outcome was 12-month mortality. Secondary outcomes were functional outcome of survivors at 3 and 12 months, and the need for invasive mechanical ventilation (IMV) or continuous renal replacement therapy (CRRT) during the ICU stay. Functional outcome was assessed by the Glasgow Outcome Scale Extended (GOSE, range 1-8, with < 5 representing an unfavourable outcome). Associations between plasma calprotectin and outcomes were examined in binary logistic regression analyses adjusted for age, sex, BMI, hypertension, smoking, and creatinine. RESULTS: High plasma calprotectin on admission and day 7 was independently associated with increased 12-month mortality. Increasing calprotectin from admission to day 7 was independently associated with higher mortality at 12 months [OR 2.10 (95% CI 1.18-3.74), p = 0.012], unfavourable functional outcome at 3 months [OR 2.53 (95% CI 1.07-6.10), p = 0.036], and the use of IMV [OR 2.23 (95% CI 1.10-4.53), p = 0.027)] and CRRT [OR 2.07 (95% CI 1.07-4.00), p = 0.031)]. A receiver operator characteristic (ROC) model including day 7 calprotectin and age was a good predictor of 12-month mortality [AUC 0.79 (95% CI 0.74-0.84), p < 0.001]. Day 7 calprotectin alone predicted an unfavourable functional outcome at 3 months [AUC 0.67 (95% CI 0.58-0.76), p < 0.001]. CONCLUSION: In critically ill COVID-19 patients, increasing calprotectin levels after admission to the ICU are associated with 12-month mortality and unfavourable functional outcome in survivors. Monitoring plasma calprotectin dynamics in the ICU may be considered to evaluate prognosis in critical COVID-19. STUDY REGISTRATION: ClinicalTrials.gov Identifier: NCT04974775, registered April 28, 2020.