Combined use of CRP with neutrophil-to-lymphocyte ratio in differentiating between infectious and noninfectious inflammation in hemodialysis patients

We tested whether CRP combined with the neutrophil-to-lymphocyte ratio (NLR) optimizes the prediction of infectious inflammation in hemodialysis patients. We conducted a retrospective study of 774 (mean age 71.1 ± 12.8 years, 35% women) hemodialysis patients from our institution, hospitalized between 2007 and 2021 for various reasons, with CRP levels available at admission. Infection was defined according to the International Sepsis Definition Conference criteria. An algorithm for the optimal CRP and NLR cutoff points for predicting infection was developed based on a decision tree analysis in the training cohort (n = 620) and then tested in the validation cohort (n = 154). A CRP level above 40 mg/L (obtained as the cutoff point in predicting infections in the training group, using ROC curve analysis) predicted an infection diagnosis with a sensitivity of 75% and a specificity of 76% with an odds ratio (OR) of 9.37 (95% CI: 5.36-16.39), according to a multivariate logistic regression analysis. Whereas, CRP levels above 23 mg/L together with an NLR above 9.7 predicted an infection diagnosis with a sensitivity of 69% and a specificity of 84% with an OR of 25.59 (95% CI: 9.73-67.31). All these results were reproduced in the validation set. Combined use of CRP with NLR may lower the CRP cutoff point in distinguishing between infectious and noninfectious inflammation in hemodialysis patients.

Effluent lipopolysaccharide is a prompt marker of peritoneal dialysis-related gram-negative peritonitis

BACKGROUND

To investigate the value of effluent lipopolysaccharide (LPS) for early detection of gram-negative peritonitis (GNP) in peritoneal dialysis (PD) patients.

METHODS

PD-related peritonitis episodes occurring between January 2016 and December 2018 were included in the study. Effluent LPS and the other infectious parameters were measured at peritonitis presentation, and peritonitis was categorized as GNP, non-GNP, and culture-negative peritonitis. Receiver operating characteristic (ROC) analysis was employed to evaluate the efficacy of effluent LPS to distinguish GNP.

RESULTS

A total of 161 peritonitis episodes were analyzed, including 49 GNP episodes and 82 non-GNP episodes. In contrast with non-GNP, GNP presented with higher effluent leukocyte count (3236 (1497-6144) vs. 1904 (679-4071) cell mm^-3, p = 0.008), increased effluent LPS (1.552 (0.502-2.500) vs. 0.016 (0.010-0.030) EU mL^-1, p < 0.001), lower blood leukocyte count (9.95 ± 3.18 vs. 11.56 ± 4.37 × 10⁹ L^-1, p = 0.017), greater neutrophil predominance (87.1 ± 4.6% vs. 83.4 ± 7.7%, p = 0.001), and greater "procalcitonin" (PCT, 4.90 (2.20-12.60) vs. 1.00 (0.51-4.07) µg L^-1, p < 0.001). It took 5.2 ± 3.1 h to report the results of effluent LPS. Effluent LPS cutoff value of >0.035 EU mL^-1 showed an area under the ROC curve of 0.972 (95% CI 0.951-0.994, p < 0.001) in differentiating GNP from non-GNP with a sensitivity of 100% and a specificity of 80.5%, and its joint utilization with PCT further increased the specificity (91.4%) to discriminate GNP.

CONCLUSIONS

PD effluent LPS could be an applicable early marker of gram-negative organism-related peritonitis in PD patients.

Selective cathepsin S inhibition attenuates atherosclerosis in apolipoprotein E-deficient mice with chronic renal disease

Chronic renal disease (CRD) accelerates the development of atherosclerosis. The potent protease cathepsin S cleaves elastin and generates bioactive elastin peptides, thus promoting vascular inflammation and calcification. We hypothesized that selective cathepsin S inhibition attenuates atherogenesis in hypercholesterolemic mice with CRD. CRD was induced by 5/6 nephrectomy in high-fat high-cholesterol fed apolipoprotein E-deficient mice. CRD mice received a diet admixed with 6.6 or 60 mg/kg of the potent and selective cathepsin S inhibitor RO5444101 or a control diet. CRD mice had significantly higher plasma levels of osteopontin, osteocalcin, and osteoprotegerin (204%, 148%, and 55%, respectively; P < 0.05), which were inhibited by RO5444101 (60%, 40%, and 36%, respectively; P < 0.05). Near-infrared fluorescence molecular imaging revealed a significant reduction in cathepsin activity in treated mice. RO5444101 decreased osteogenic activity. Histologic assessment in atherosclerotic plaque demonstrated that RO5444101 reduced immunoreactive cathepsin S (P < 0.05), elastin degradation (P = 0.01), plaque size (P = 0.01), macrophage accumulation (P < 0.01), growth differentiation factor-15 (P = 0.0001), and calcification (alkaline phosphatase activity, P < 0.01; osteocalcin, P < 0.05). Furthermore, cathepsin S inhibitor or siRNA significantly decreased expression of growth differentiation factor-15 and monocyte chemotactic protein-1 in a murine macrophage cell line and human primary macrophages. Systemic inhibition of cathepsin S attenuates the progression of atherosclerotic lesions in 5/6 nephrectomized mice, serving as a potential treatment for atherosclerosis in patients with CRD.

Significance of serum procalcitonin as biomarker for detection of bacterial peritonitis: a systematic review and meta-analysis

Background

Bacterial peritonitis is serious disease and remains a diagnostic challenge for clinicians. Many studies have highlighted the potential usefulness of procalcitonin (PCT) for identification of bacterial peritonitis, however, the overall diagnostic value of PCT remains unclear. Therefore, we performed a meta-analysis to assess the accuracy of PCT for detection of bacterial peritonitis.

Methods

We performed a systematic searched in MEDLINE, EMBASE, SCOPUS, China Biology Medicine Database (CBM), China National Knowledge Infrastructure Database (CNKI) and Cochrane databases for trials that evaluated the diagnostic role of PCT for bacterial peritonitis. Sensitivity, specificity and other measures of accuracy of PCT were pooled using bivariate random effects models.

Results

Eighteen studies involving 1827 patients were included in the present meta-analysis. The pooled sensitivity and specificity of serum PCT for the diagnosis bacterial peritonitis were 0.83 (95% CI: 0.76–0.89) and 0.92 (95% CI: 0.87–0.96), respectively. The positive likelihood ratio was 11.06 (95% CI: 6.31–19.38), negative likelihood ratio was 0.18 (95% CI: 0.12–0.27) and diagnostic odds ratio (DOR) was 61.52 (95% CI: 27.58–137.21). The area under the receiver operating characteristic curve (AUROC) was 0.94. Use of a common PCT cut-off value could improve the DOR to 75.32 and the AUROC to 0.95. Analysis of the seven studies that measured serum C-reactive protein (CRP) indicated that PCT was more accurate than CRP for the diagnosis of bacterial peritonitis.

Conclusions

Our results indicate that PCT determination is a relatively sensitive and specific test for the diagnosis of bacterial peritonitis. However, with regard to methodological limitations and significant heterogeneity, medical decisions should be based on both clinical findings and PCT test results.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-452) contains supplementary material, which is available to authorized users.

American Thyroid Association statement on optimal surgical management of goiter

BACKGROUND

Goiter, or benign enlargement of the thyroid gland, can be asymptomatic or can cause compression of surrounding structures such as the esophagus and/or trachea. The options for medical treatment of euthyroid goiter are short-lived and are limited to thyroxine hormone suppression and radioactive iodine ablation. The objective of this statement article is to discuss optimal surgical management of goiter.

METHODS

A task force was convened by the Surgical Affairs Committee of the American Thyroid Association and was tasked with writing of this article.

RESULTS/CONCLUSIONS

Surgical management is recommended for goiters with compressive symptoms. Symptoms of dyspnea, orthopnea, and dysphagia are more commonly associated with thyromegaly, in particular, substernal goiters. Several studies have demonstrated improved breathing and swallowing outcomes after thyroidectomy. With careful preoperative testing and thoughtful consideration of the type of anesthesia, including the type of intubation, preparation for surgery can be optimized. In addition, planning the extent of surgery and postoperative care are necessary to achieve optimal results. Close collaboration of an experienced surgical and anesthesia team is essential for induction and reversal of anesthesia. In addition, this team must be cognizant of complications from massive goiter surgery such as bleeding, airway distress, recurrent laryngeal nerve injury, and transient hypoparathyroidism. With careful preparation and teamwork, successful thyroid surgery can be achieved.

Pathogen-specific local immune fingerprints diagnose bacterial infection in peritoneal dialysis patients

Accurate and timely diagnosis of bacterial infection is crucial for effective and targeted treatment, yet routine microbiological identification is inefficient and often delayed to an extent that makes it clinically unhelpful. The immune system is capable of a rapid, sensitive and specific detection of a broad spectrum of microbes, which has been optimized over millions of years of evolution. A patient's early immune response is therefore likely to provide far better insight into the true nature and severity of microbial infections than conventional tests. To assess the diagnostic potential of pathogen-specific immune responses, we characterized the local responses of 52 adult patients during episodes of acute peritoneal dialysis (PD)-associated peritonitis by multicolor flow cytometry and multiplex ELISA, and defined the immunologic signatures in relation to standard microbiological culture results and to clinical outcomes. We provide evidence that unique local "immune fingerprints" characteristic of individual organisms are evident in PD patients on the day of presentation with acute peritonitis and discriminate between culture-negative, Gram-positive, and Gram-negative episodes of infection. Those humoral and cellular parameters with the most promise for defining disease-specific immune fingerprints include the local levels of IL-1β, IL-10, IL-22, TNF-α, and CXCL10, as well as the frequency of local γδ T cells and the relative proportion of neutrophils and monocytes/macrophages among total peritoneal cells. Our data provide proof of concept for the feasibility of using immune fingerprints to inform the design of point-of-care tests that will allow rapid and accurate infection identification and facilitate targeted antibiotic prescription and improved patient management.

Diagnostic value of serum procalcitonin in patients with chronic renal insufficiency: a systematic review and meta-analysis

BACKGROUND

The diagnostic value of procalcitonin (PCT) for patients with renal impairment is unclear.

METHODS

We searched multiple databases for studies published through December 2011 that evaluated the diagnostic performance of PCT among patients with renal impairment and suspected systemic bacterial infection. We summarized test performance characteristics with the use of forest plots, hierarchical summary receiver operating characteristic (HSROC) curves, and bivariate random effects models.

RESULTS

Our search identified 201 citations, of which seven diagnostic studies evaluated 803 patients and 255 bacterial infection episodes. HSROC-bivariate pooled sensitivity estimates were 73% [95% confidence interval (95% CI) 54-86%] for PCT tests and 78% (95% CI 52-92%) for CRP tests. Pooled specificity estimates were higher for both PCT and CRP tests [PCT, 88% (95% CI 79-93%); CRP, 84% (95% CI, 52-96%)]. The positive likelihood ratio for PCT [likelihood (LR)+ 6.02, 95% CI 3.16-11.47] was sufficiently high to be qualified as a rule-in diagnostic tool, while the negative likelihood ratio was not low enough to be used as a rule-out diagnostic tool (LR- 0.31, 95% CI 0.17-0.57). There was no consistent evidence that PCT was more accurate than CRP test for the diagnosis of systemic infection among patients with renal impairment.

CONCLUSIONS

Both PCT and CRP tests have poor sensitivity but acceptable specificity in diagnosing bacterial infection among patients with renal impairment. Given the poor negative likelihood ratio, its role as a rule-out test is questionable.

Recent peritonitis associates with mortality among patients treated with peritoneal dialysis

Peritonitis is a major complication of peritoneal dialysis, but the relationship between peritonitis and mortality among these patients is not well understood. In this case-crossover study, we included the 1316 patients who received peritoneal dialysis in Australia and New Zealand from May 2004 through December 2009 and either died on peritoneal dialysis or within 30 days of transfer to hemodialysis. Each patient served as his or her own control. The mean age was 70 years, and the mean time receiving peritoneal dialysis was 3 years. In total, there were 1446 reported episodes of peritonitis with 27% of patients having ≥ 2 episodes. Compared with the rest of the year, there were significantly increased odds of peritonitis during the 120 days before death, although the magnitude of this association was much greater during the 30 days before death. Compared with a 30-day window 6 months before death, the odds for peritonitis was six-fold higher during the 30 days immediately before death (odds ratio, 6.2; 95% confidence interval, 4.4-8.7). In conclusion, peritonitis significantly associates with mortality in peritoneal dialysis patients. The increased odds extend up to 120 days after an episode of peritonitis but the magnitude is greater during the initial 30 days.

[Prognostic value of procalcitonin, C-reactive protein and leukocytes in septic shock]

OBJECTIVES

This study evaluates the potential prognostic value of serial measurements of different biomarkers (procalcitonin [PCT], C-reactive protein and leukocytes [CRP]) in septic shock patients.

DESIGN

Prospective observational study.

SETTING

Intensive care unit of a third-level University Hospital.

PATIENTS

The study comprised a total of 88 septic shock patients defined using the 2001 Consensus Conference SCCM/ESICM/ACCP/ATS/SIS criteria. The PCT, CRP and leukocytes were recorded on admission to the ICU and again 72 hours after admission.

INTERVENTIONS

None.

RESULTS

Those patients with increasing procalcitonin levels showed higher hospital mortality than those with a decreasing levels (58.8% vs. 15.4%, P<0.01). No such effect was observed in relation to C-reactive protein or leukocytes. The best area under the curve for prognosis was for procalcitonin clearance (0.79). A procalcitonin clearance of 70% or higher offered a sensitivity and specificity of 94.7% and 53%, respectively.

CONCLUSIONS

Serial procalcitonin measurements are more predictive of the prognosis of septic shock patients than single measurements of this parameter. The prognostic reliability of the latter is also better than in the case of C-reactive protein and leukocytes. The application of serial procalcitonin measurements may allow the identification of those septic patients at increased mortality risk, and help improve their treatment.