The importance of determining procalcitonin and C reactive protein in different stages of sepsis

C-reactive protein for diagnosing late-onset infection in newborn infants

BACKGROUND

Late-onset infection is the most common serious complication associated with hospital care for newborn infants. Because confirming the diagnosis by microbiological culture typically takes 24 to 48 hours, the serum level of the inflammatory marker C-reactive protein (CRP) measured as part of the initial investigation is used as an adjunctive rapid test to guide management in infants with suspected late-onset infection.

OBJECTIVES

To determine the diagnostic accuracy of serum CRP measurement in detecting late-onset infection in newborn infants.

SEARCH METHODS

We searched electronic databases (MEDLINE, Embase, and Science Citation Index to September 2017), conference proceedings, previous reviews, and the reference lists of retrieved articles.

SELECTION CRITERIA

We included cohort and cross-sectional studies evaluating the diagnostic accuracy of serum CRP levels for the detection of late-onset infection (occurring more than 72 hours after birth) in newborn infants.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility for inclusion, evaluated the methodological quality of included studies, and extracted data to estimate diagnostic accuracy using hierarchical summary receiver operating characteristic (SROC) models. We assessed heterogeneity by examining variability of study estimates and overlap of the 95% confidence interval (CI) in forest plots of sensitivity and specificity.

MAIN RESULTS

The search identified 20 studies (1615 infants). Most were small, single-centre, prospective cohort studies conducted in neonatal units in high- or middle-income countries since the late 1990s. Risk of bias in the included studies was generally low with independent assessment of index and reference tests. Most studies used a prespecified serum CRP threshold level as the definition of a 'positive' index test (typical cut-off level between 5 mg/L and 10 mg/L) and the culture of a pathogenic micro-organism from blood as the reference standard.At median specificity (0.74), sensitivity was 0.62 (95% CI 0.50 to 0.73). Heterogeneity was evident in the forest plots but it was not possible to conduct subgroup or meta-regression analyses by gestational ages, types of infection, or types of infecting micro-organism. Covariates for whether studies used a predefined threshold or not, and whether studies used a standard threshold of between 5 mg/L and 10 mg/L, were not statistically significant.

AUTHORS' CONCLUSIONS

The serum CRP level at initial evaluation of an infant with suspected late-onset infection is unlikely to be considered sufficiently accurate to aid early diagnosis or select infants to undergo further investigation or treatment with antimicrobial therapy or other interventions.

Serum procalcitonin correlates with colonoscopy findings and can guide therapeutic decisions in postoperative ischemic colitis

BACKGROUND

Postoperative ischaemic colitis (POIC) is a life-threatening vascular gastrointestinal condition. Serum procalcitonin (PCT) levels be of value in the detection of necrosis.

AIMS

To evaluate the correlation between serum PCT levels and the colonoscopic assessment of the severity of POIC.

METHODS

Between January 2007 and November 2014, 150 patients with POIC and PCT data were included in the study. The main outcome measure was the correlation between serum PCT and the colonoscopy-based assessment of the severity of POIC (according to Favier's classification: stage 1/2 without multi-organ failure vs. stage 2/3 with multi-organ failure).

RESULTS

Eighty-five percent of the stage 1 cases (n=22) had a serum PCT level ≤2μg/L; 63% (n=19) of the stage 2 cases with multi-organ failure had a PCT level between 4 and 8μg/L, and 70% (n=52) of the stage 3 cases had a PCT level ≥8μg/L. The PCT level was strongly correlated with the Favier stage (Spearman's rho: 0.701; p<0.0001). PCT levels were similar in stage 2 cases with multi-organ failure and in stage 3 cases (16.06μg/L vs. 7.79μg/L, respectively; p=0.35).

CONCLUSION AND RELEVANCE

Serum PCT is correlated with stage 2/3 POIC requiring surgery. If PCT ≥5μg/L, surgery should be considered.

Predictive values for procalcitonin in the diagnosis of neonatal sepsis

BACKGROUND

Early diagnosis of neonatal sepsis followed by appropriate treatment decreases mortality and morbidity in infants. The aim of this study is to assess the role of procalcitonin (PCT) as a marker in the early diagnosis of neonatal sepsis.

METHODS

We present a cross sectional study where 35 neonates with early onset sepsis (admitted to the Neonatal Intensive Care Units at El-Minia Children University Hospital from August 2012 to August 2013) were included in the study. Another 35 healthy neonates with no clinical or biological data of infection were included as a control group. Subjects were subjected to a thorough history taking and routine laboratory investigations. Serum PCT and C-reactive protein (CRP) levels were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Mean levels of PCT and CRP in neonates with sepsis were significantly higher than in the control group (p=0.0001). There was a moderate, but significant, positive correlation between PCT and C-reactive protein (p=0.001, r=0.55) and an insignificant correlation between procalcitonin and total leukocytic count among the neonates with sepsis (p=0.2, r=0.2). In addition, procalcitonin had high sensitivity, specificity, a high positive predictive value, and a high negative predictive value (80%, 85.7%, 84.8%, and 81.1% respectively). Procalcitonin showed higher sensitivity when compared to CRP.

CONCLUSION

Procalcitonin is a sensitive, independent, and useful biomarker in comparison to CRP in early diagnosis of neonatal sepsis.

Serum value of procalcitonin as a marker of intestinal damages: type, extension, and prognosis

BACKGROUND

Ischemic and necrotic damages are complications of digestive diseases and require emergency management. Nevertheless, the decision to surgically manage could be delayed because of no sufficiently preoperative accurate marker of ischemia diagnosis, extension, and prognosis.

METHODS

The aim of this study was to assess the predictive value of serum procalcitonin (PCT) levels for diagnosing intestinal necrotic damages, their extension, and their prognosis in patients with ischemic disease including ischemic colitis and mesenteric infarction by a gray zone approach. Between January 2007 to June 2014, 128 patients with ischemic colitis and mesenteric infarction (codes K55.0 and K51.9) were operated, for whom data on PCT were available. We perform a retrospective, multicenter review of their medical records. Patients were divided into subgroups: ischemia (ID group) versus necrosis (ND group); the extension [focal (FD) vs. extended (ED)] and the vital status [deceased (D) vs. alive (A)].

RESULTS

PCT levels were higher in the ND (n = 94; p = 0.009); ED (n = 100; p = 0.02); and D (n = 70; p = 0.0003) groups. With a gray zone approach, the predictive thresholds were (i) for necrosis 2.473 ng/mL, (ii) for extension 3.884 ng/mL, and (iii) for mortality 7.87 ng/mL.

CONCLUSION

In our population, PCT could be used as a marker of necrosis; especially in case of extended damages and reflects the patient's prognosis.

Serum procalcitonin for predicting the failure of conservative management and the need for bowel resection in patients with small bowel obstruction

BACKGROUND

Ischemia and necrosis are complications of small bowel obstruction (SBO) and require rapid surgical treatment. At present, there are no sufficiently accurate preoperative biomarkers of ischemia or necrosis. The objective of the current study was to evaluate the value of serum procalcitonin levels for predicting conservative management failure and the presence of intraoperatively observed bowel ischemia (reversible or not) in patients with SBO.

STUDY DESIGN

One hundred and sixty-six participants of 242 in a randomized controlled trial focusing on the management of SBO (Acute Bowel Obstruction Diagnostic study [ABOD], NCT00389116) had available data on procalcitonin and were included in the study. The primary study objective was to determine whether serum procalcitonin could identify patients in whom conservative management (CM) failed (the surgical management [SM] group) and the subset of SM patients with intraoperatively observed ischemia (reversible or not). For the analysis, the patients were divided into subgroups according to the success or failure of CM and (for surgically managed patients) the presence or absence of intraoperative ischemia (reversible or not).

RESULTS

Procalcitonin levels were higher in the SM group (n = 35) than in the CM group (n = 131) (0.53 vs 0.14 ng/mL; p = 0.031) and higher in the group managed surgically with ischemia (n = 12) than patients managed surgically without intraoperative ischemia (n = 23) (1.16 vs 0.21 ng/mL, respectively; p < 0.001). A multiple logistic regression showed that procalcitonin is a risk factor for CM failure (odds ratio = 3.5; 95% CI, 1.4-8.5; p = 0.006) and for ischemia (reversible or not) (odds ratio = 46.9; 95% CI, 4.0-547.3; p < 0.001).

CONCLUSIONS

Procalcitonin can help predict CM failure and occurrence of bowel ischemia (reversible or not) in SBO patients, but additional studies are needed.

Screening for surgical nosocomial infections by crossing databases

Surgical site infection (SSI) is a major cause of morbidity and mortality, and they are the third cause of nosocomial infections. It has been shown that surveillance can reduce the rate of these infections because the publication of the results that introduce a interrogation on her surgical pratices. However, surveillance requires considerable medical resources. Our objective is to validate a computer algorithm that uses microbiological results and the results of a C-reactive protein (CRP) assay and granulocyte count to detect SSIs.

MATERIALS AND METHODS

All patients who underwent colorectal surgery between the 1st of January and the 30th of June 2009 were included. Administrative, surgical and microbiological data and the appearance of neutrophilia and CRP after surgery and during hospitalization were collected. The algorithm uses four biological variables: CRP, neutrophils, and the bacterium found on the positive sample. The CRP and neutrophil variables were coded in 0 or 1. CRP was coded as 1 if the sample was below 5mg/l at the time of the operation and increased to more than 60mg/l in the 30 days immediately after post-operation. Neutrophils were coded as 1 if the sample was normal at the time of the operation and increased to more than 12,000cells/mm(3) in the 30 days immediately after post-operation. The "type of sample" and "bacterium" variables were coded in categories. For the type of sample, we coded 3 if the sampling site was related to the surgical site, 2 if the sampling site was potentially linked to the surgical site, 1 if the sampling site was not directly or indirectly related to the surgical site and 0 if there was no sample. Regarding the bacteria, we coded 3 for bacteria found in over 5% of SSIs, 2 for bacteria found in 2-5% of SSIs, 1 for bacteria found in less than 2% of SSIs and 0 if there were no bacteria. The algorithm calculates a score from 1 to 5.

RESULTS

Our study included 195 operations, out of which it was possible to study 168. Following the operations, we found neutrophilia above 12,000cells/mm(3) in 41.5% of cases and CRP above 60mg/l in 64.6% of cases. Thirty-seven operations (22%) were complicated by an SSI. The positive predictive values and the negative predictive values in our algorithm were 74.07% and 87.94%, respectively, and the number of records that remain to be investigated is 27 out of 168.

CONCLUSIONS

Linking databases from bacteriology and biology with those containing the hospital records of surgical procedures is a simple method for identifying surgical nosocomial infections.