C-reactive protein and fever in neutropenic patients

Comparison of procalcitonin and C-reactive protein as early diagnostic marker for the identification of transplant-related adverse events after allogeneic hematopoietic stem cell transplantation in pediatric patients

PURPOSE

To evaluate serum procalcitonin (PCT) and C-reactive protein (CRP) as diagnostic biomarkers of transplant-related adverse events (TRAE) in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT).

METHODS

This study analyzed PCT and CRP levels of 214 pediatric patients with a median age of 8.5 years (0.4-17.8 years) undergoing allogeneic HSCT with respect to major TRAE.

RESULTS

26 patients (12.1%) did not experience TRAE (control group), and 188 (87.9%) experienced median 2 (range 1-4) TRAE. Median CRP and PCT were highly and significantly increased during sepsis/SIRS and bacteremia (17.24 mg/dl | 6.30 ng/ml; p < 0.0001 vs. prior values), graft rejection (14.73 mg/dl | 3.20 ng/ml; p < 0.0001), and liver GvHD (6.88 mg/dl | 2.29 ng/ml; p < 0.01). Strong CRP increases and slight/minimal/no PCT increases occurred during fungemia (8.85 mg/dl | 0.72 ng/ml; p < 0.001), intestinal GvHD (8.73 mg/dl | 1.06 ng/ml; p < 0.0001), VOD (10.84 mg/dl | 0.59 ng/ml; p < 0.01), mucositis (8.84 mg/dl | 0.81 ng/ml; p < 0.0001), and viremia (3.62 mg/dl; p < 0.0001 | 0.43 ng/ml; below normal limit). During skin GvHD, CRP and PCT were slightly increased (2.03 mg/dl | 0.93 ng/ml; p < 0.0001).

CONCLUSIONS

CRP and PCT did not show congruent changes during TRAE. PCT was a clinically relevant marker for the early detection and differentiation of severe mucositis and sepsis/SIRS and bacteremia during the critical neutropenic period after HSCT. PCT helped to discriminate acute intestinal GvHD from adenovirus viremia and liver GvHD from hepatic VOD. Thus, PCT may be a valuable parameter to enable a prompt and appropriate treatment during these complications, improving patient outcomes.

Predictive value of interleukin-5 and monocyte chemotactic protein-1 for bacteremia in children with febrile neutropenia

A variety of clinical and laboratory parameters have been used to predict bacteremia. We hypothesize that the generation of a cytokine profile could be used to identify patients at higher risk of bacteremia at the time of presentation with febrile neutropenia. We prospectively evaluated children with cancer who presented with an episode of febrile neutropenia. A multiplexed flow cytometric assay was performed which measured 15 cytokines and chemokines obtained before the initiation of antibiotics. Fifty-eight episodes of chemotherapy-induced febrile neutropenia were included in this study during which 4 patients (7%) had bacteremia. An interleukin-5 level of >8 pg/dL had a sensitivity of 67% and a specificity of 96% to predict bacteremia. An monocyte chemotactic protein-1 level >1650 pg/dL had a sensitivity of 80% and a specificity of 82% to predict bacteremia. Erythrocyte sedimentation rate, C-reactive protein, protein C, and other cytokines/chemokines were not predictive of bacteremia. Elevations of interleukin-5 and monocyte chemotactic protein-1 are predictive of bacteremia in children with cancer who have febrile neutropenia. Prospective studies should be undertaken to determine whether these parameters retain predictive value in a larger series of patients and can select children for outpatient management or early discharge.

Predictive factors of poor prognosis in cancer patients with chemotherapy-induced febrile neutropenia

OBJECTIVES

We intended to determine the predictive factors of poor prognosis in cancer patients with chemotherapy-induced febrile neutropenia (FN).

METHODS

From January 1, 2007 to December 31, 2008, 396 episodes of FN in 346 cancer patients were retrospectively analyzed. Clinical and laboratory findings and Multinational Association of Supportive Care in Cancer (MASCC) risk-index score were analyzed and correlated with outcome.

RESULTS

Of the 396 episodes, 73 (18.4%) had serious medical complications including 15 (3.8%) deaths. There was significant difference between unfavorable and favorable outcomes in age, gender, hypotension, tachypnea, duration of fever ≤24 h before admission (44.4% vs. 61.3%), interval of ≤7 days since last chemotherapy (34.2% vs. 16.1%), and duration of neutropenia ≥4 days (34.2% vs. 15.8%; P < 0.05 each), as did C-reactive protein (CRP; 15.0 vs. 7.5 mg dL(-1)) and platelet count (66.4 × 10(3) vs. 123.7 × 10(3) mm(-3);P < 0.001 each). MASCC score was significantly lower in unfavorable outcomes than favorable outcomes (19.0 vs. 24.6, P < 0.001). However, prophylactic antibiotics, treatment with granulocyte colony-stimulating factor (G-CSF), and history of FN were not associated with outcome. On multivariate analysis, MASCC risk-index score (OR 23.2, 95% CI 10.48-51.37), tachypnea (OR 3.61, 95% CI 1.44-9.08), thrombocytopenia (OR 3.41, 95% CI 1.69-6.89), increased CRP (OR 3.23, 95% CI 1.62-6.45), and prolonged neutropenia (OR 2.52, 95% CI 1.21-5.25) were independent predictors of unfavorable outcomes.

CONCLUSION

MASCC risk-index score <21, tachypnea, thrombocytopenia, increased CRP, and prolonged neutropenia may be strongly associated with poor outcomes in cancer patients with FN.

Serum protein-bound uraemic toxins and clinical outcomes in haemodialysis patients

BACKGROUND

The protein-bound uraemic toxin p-cresol is associated with immunodeficiency in haemodialysis (HD) patients. We investigated the effect of serum p-cresol, indoxyl sulphate and other variables on clinical outcomes in HD patients during a 20-month follow-up.

METHODS

We enrolled 100 stable HD patients from a single medical centre. The primary outcomes were infection-related hospitalization, cardiovascular events and all-cause mortality. Serum total and free p-cresol and indoxyl sulphate levels were measured using ultra-performance liquid chromatography. Biochemical data were collected concurrently.

RESULTS

Multivariate logistic regression analysis revealed that infection-related hospitalization correlated with free p-cresol (adjusted odds ratio: 1.70, P = 0.01) and highly sensitive C-reactive protein (hsCRP) (adjusted odds ratio: 2.07, P = 0.01); cardiovascular event was associated with free p-cresol (adjusted odds ratio: 1.78, P = 0.01) and nPCR (adjusted odds ratio: 0.01, P = 0.02); and all-cause mortality was related to albumin (adjusted odds ratio: 0.04, P = 0.01). The Kaplan-Meier method showed that free and total p-cresol were significantly associated with cardiovascular events (log-rank P < 0.01 and log-rank P < 0.01, respectively). Serum free p-cresol seemed to have a trend to correlate with infection-related hospitalization during a 20-month follow-up (log-rank P = 0.05).

CONCLUSIONS

Serum free and total p-cresol levels were significantly related to cardiovascular events. In addition, serum free p-cresol and hsCRP levels were also found to be associated with infection-related hospitalization.

Characteristics of febrile patients with normal white blood cell counts and high C-reactive protein levels in an emergency department

Fever is one of the more common chief complaints of patients who visit emergency departments (ED). Many febrile patients have markedly elevated C-reactive protein (CRP) levels and normal white blood cell (WBC) counts. Most of these patients have bacterial infection and no previous underlying disease of impaired WBC functioning. We reviewed patients who visited our ED between November 2003 and July 2004. The WBC count and CRP level of patients over 18 years of age who visited the ED because of or with fever were recorded. Patients who had normal WBC count (4,000–10,000/mL) and high CRP level (> 100 mg/L) were included. The data, including gender, age and length of hospital stay, were reviewed. Underlying diseases, diagnosis of the febrile disease and final condition were recorded according to the chart. Within the study period, 54,078 patients visited our ED. Of 5,628 febrile adults, 214 (3.8%) had elevated CRP level and normal WBC count. The major cause of febrility was infection (82.24%). Most of these patients were admitted (92.99%). There were 32 patients with malignant neoplasm, nine with liver cirrhosis, 66 with diabetes mellitus and 11 with uremia. There were no significant differences in age and gender between patients with and those without neoplasm. However, a higher inhospital mortality rate and other causes of febrility were noted in patients with neoplasm. It was not rare in febrile patients who visited the ED to have a high CRP level but normal WBC count. These patients did not necessarily have an underlying malignant neoplasm or hematologic illness. Factors other than malignant neoplasm or hematologic illness may be associated with the WBC response, and CRP may be a better indicator of infection under such conditions.

Neutropenic fever and severe sepsis in adult acute myeloid leukemia (AML) patients receiving intensive chemotherapy: Causes and consequences

The objective of this study was to evaluate etiology and consequences of neutropenic fever in AML patients. Two hundred and ninety neutropenic periods following chemotherapy in 84 AML patients were retrospectively evaluated. Neutropenic fever was found in 280 periods (97%). Severe sepsis developed in 35 occasions (13%) and 9 patients (11%) died due to severe sepsis. In 165 episodes with neutropenic fever (59%), the potential causative organism was found in blood cultures. Gram-negative bacteria were more commonly found in patients who developed severe sepsis (40% vs. 23%, p = 0.03). CRP after 2 - 3 days from start with fever was higher in patients with severe sepsis (190 mg/L vs. 96 mg/L, p < 0.001) but the rise in CRP rather coincided than preceded with the development of severe sepsis. Severe sepsis is associated with significant mortality in AML patients. Earlier methods than CRP are needed to predict development of severe sepsis.

Role of procalcitonin and CRP in differentiating a stable from a deteriorating clinical course in pediatric febrile neutropenia

In clinical practice, when neutropenic-fever patients present with no microbiologically and clinically defined infection, the risk of underestimating an occult infection is of major concern, the clinicians have to make a decision on when to modify antibiotic therapy. Hence, a reliable, specific, and sensitive marker, which is regulated independently from the leukocyte count and the underlying disease, is needed for the early diagnosis of infections in cases of neutropenic fever. We have evaluated the diagnostic and follow-up value of procalcitonin (PCT) compared with C-reactive protein (CRP) and erythrocyte sedimentation rate in documenting the infection in neutropenic-fever patients undergoing intensive chemotherapy, as evidenced by the durational change in these parameters in the presence of defined infection. Forty-nine patients, who had 60 febrile episodes, and who were hospitalized in the Hacettepe University Ihsan Doğramaci Children's Hospital between January 1, 2004 and January 1, 2005 were included in this prospective study. All patients had been diagnosed with neutropenic fever after intensive chemotherapy. In our study, PCT and CRP levels were significantly higher in neutropenic-fever patients (group I and group II separately) than in control patients (P<0.001) throughout the study period; but erythrocyte sedimentation rate levels did not show any significant difference (P>0.05). In sequential analyses of patients without documented infections, the median of PCT concentrations shows a tendency to fall after the 8th hour of onset of fever, whereas in patients with documented infections PCT concentrations fell after the 48th hour. In conclusion, our study suggests that PCT, when measured periodically, is a more useful diagnostic inflammation parameter in pediatric neutropenic-fever patients than CRP, both in estimating the severity of the infection and, the duration and origin of the fever. Hence, PCT might be helpful when deciding on initial therapy modification.

Utility of procalcitonin concentration in the evaluation of patients with malignant diseases and elevated C-reactive protein plasma concentrations

BACKGROUND

Elevated plasma concentrations of the C-reactive protein (CRP) are frequently found in patients with malignant diseases. Discrimination between infection and noninfectious acute-phase reactions is essential for therapeutic decisions.

METHODS

Because increased procalcitonin (PCT) concentrations have been described predominantly in patients with a systemic infection, PCT plasma concentrations were measured prospectively in 111 patients with a hemato-oncological condition with a CRP concentration >8 mg/L.

RESULTS

Documented cases of infection were identified in 42 patients, 39 patients had unexplained fever, and 30 patients had no signs of infection. Twenty patients in the latter group were classified as having an elevated CRP concentration caused by a high tumor load (tumor group), and 8 had elevated concentrations that were drug related (drug group). Median CRP concentrations did not differ significantly between groups of patients with and without infection. PCT concentrations were higher in patients with an infection than in patients without an infection and were within the normal range in all patients in the drug and tumor groups. As shown by receiver operating characteristic analysis, PCT concentration was a significant discriminator between having and not having infection, having infection and being in the tumor group, and having infection and being in the drug group. In contrast, CRP concentration was only a predictor of being in the drug group, when the cut-off point was set at 85.1 mg/L, which limited its clinical applicability.

CONCLUSIONS

PCT concentration contributes significantly to the differential diagnosis for elevated CRP concentrations in patients with hemato-oncological conditions and facilitates therapeutic decisions.

Patterns of C-reactive protein release following allogeneic stem cell transplantation are correlated with leukemic relapse

The C-reactive protein (CRP) is an acute-phase protein produced by hepatocytes, and is a reliable marker of systemic inflammation, which is relevant to the release of the proinflammatory cytokines. The value of monitoring the CRP levels after stem cell transplantation (SCT) can identify patients at risk of treatment-related complications and mortality. Inflammatory cytokines facilitate donor T-cell activation via antigen presenting cells immediately after SCT. This study examined the relationship between the post-SCT CRP levels and a leukemic relapse. Fifty-four consecutively transplanted patients who relapsed after the allogeneic SCT were compared with nonrelapsing patients. The serum CRP levels were measured on day 0 and every 7 days thereafter until 4 weeks after the SCT. The mean CRP levels throughout the early post-SCT episode were significantly lower in the relapsing patients than in those who did not experience relapse (mean+/-s.e.: 26.8 +/- 6.3 vs 65.3 +/- 9.4 for first week, P = 0.001; 23.9 +/- 3.8 vs 44.6 +/- 6.6 for second week, P = 0.008). Univariate analysis showed that the CRP level on the first and second week, and graft-versus-host disease were significantly associated with a relapse. Multivariate analysis showed that the CRP level on the first week was the strongest independent variable predicting the risk of a relapse after SCT (P = 0.04). These results indicate that the serum CRP levels early after allogeneic SCT might display the graft-versus-leukemia (GvL) effect. CRP is a surrogate of the proinflammatory cytokine release that was not measured in this study. The GvL effect appears to be efficiently strengthened by the high CRP levels that may be reflecting T-cell activation.

Assessment of systemic inflammation markers to differentiate a stable from a deteriorating clinical course in patients with febrile neutropenia

In this study, we evaluated the predictive values of procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6) and serum amyloid A (SAA) for determining the clinical course in febrile neutropenic patients. Daily plasma analyses during the fever course were performed in 101 episodes with fever and chemotherapy-induced neutropenia (neutrophil count <0.5 x 10(9)/L). Procalcitonin (PCT) and IL-6 values were significantly higher in febrile episodes in patients who developed complications. Procalcitonin with a cut-off value of < or =0.4 ng/mL or IL-6 < or =50 pg/mL 3 d after fever onset indicated daily high negative predictive values (NPVs) (91-100%) for episodes with complications. No marker could predict deterioration; however, daily low plasma concentrations of PCT or IL-6 during the first 8 d of fever were found to be a good predictor of no subsequent complications in neutropenic patients and therefore to be a helpful tool for limiting anti-microbial therapy.

Use of inflammatory markers for early detection of bacteraemia in patients with febrile neutropenia

The aim of the study was to evaluate the ability of procalcitonin, C-reactive protein, serum amyloid A, interleukin-6 and interleukin-8 to predict bacteraemia during the 2 first d of fever in neutropenic patients. A total of 94 febrile neutropenic episodes in 60 patients were studied. Plasma samples were analysed at 10-h intervals from the onset of fever. Clinical events were categorized into 4 groups: 1) bacteraemia caused by other agents than coagulase-negative staphylococci (non-CNS bacteraemia) (n = 21), 2) coagulase-negative staphylococci bacteraemia (n = 15), 3) microbiologically or clinically documented infection without bacteraemia (n = 26) and 4) fever of unknown origin (n = 32). In non-CNS bacteraemia all markers, except for serum amyloid A, showed significantly higher levels compared to patients with fever of unknown origin (p < 0.05). For non-CNS bacteraemia the highest negative predictive value was found for procalcitonin (94%), followed by interleukin-6 (89%), C-reactive protein (88%) and interleukin-8 (87%). Procalcitonin, with a cut-off level of 1.4 ng/ml during 10-20 h after fever onset, showed the highest positive predictive value (67%) for a non-CNS bacteraemia. In conclusion, the value of the analysed markers to predict a non-CNS bacteraemia in neutropenic patients was limited due to low sensitivity and positive predictive value. However, procalcitonin, interleukin-6, C-reactive protein, and interleukin-8 could give useful information for the clinician in excluding a non-CNS bacteraemia.

Serum procalcitonin and C-reactive protein levels as markers of bacterial infection: a systematic review and meta-analysis

A meta-analysis was performed to evaluate the accuracy of determination of procalcitonin (PCT) and C-reactive protein (CRP) levels for the diagnosis of bacterial infection. The analysis included published studies that evaluated these markers for the diagnosis of bacterial infections in hospitalized patients. PCT level was more sensitive (88% [95% confidence interval [CI], 80%-93%] vs. 75% [95% CI, 62%-84%]) and more specific (81% [95% CI, 67%-90%] vs. 67% [95% CI, 56%-77%]) than CRP level for differentiating bacterial from noninfective causes of inflammation. The Q value for PCT markers was higher (0.82 vs. 0.73). The sensitivity for differentiating bacterial from viral infections was also higher for PCT markers (92% [95% CI, 86%-95%] vs. 86% [95% CI, 65%-95%]); the specificities were comparable (73% [95% CI, 42%-91%] vs. 70% [95% CI, 19%-96%]). The Q value was higher for PCT markers (0.89 vs. 0.83). PCT markers also had a higher positive likelihood ratio and lower negative likelihood ratio than did CRP markers in both groups. On the basis of this analysis, the diagnostic accuracy of PCT markers was higher than that of CRP markers among patients hospitalized for suspected bacterial infections.

An early increase in serum levels of C-reactive protein is an independent risk factor for the occurrence of major complications and 100-day transplant-related mortality after allogeneic bone marrow transplantation

We monitored levels of C-reactive protein (CRP) in 96 consecutive adult allogeneic BMT patients (age 15-50 years) transplanted in our unit. Major transplant-related complications (MTC) occurred in 32% of cases and included: hepatic veno-occlusive disease, pneumonitis, severe endothelial leakage syndrome and >II acute GVHD. Transplant-related mortality (TRM) before day 100 post-BMT was 13.5%. Variables included in a stepwise logistic regression model were: gender, age, disease category, donor type, T cell depletion, TBI, use of growth factors, bacteremia, mean CRP-levels >50 mg/l between days 0 and 5 (CRP day 0-5) and >100 mg/l between days 6 and 10 (CRP day 6-10) post-BMT. Only high CRP-levels (for MTC and TRM) (P < 0.001) and donor-type (for TRM) (P= 0.02) were independent risk factors. The estimated probability for MTC was 73% (CRP day 6-10 >100 mg/l) vs 17% (CRP day 6-10 <100 mg/l). Using the same cut-off levels, the probabilities for TRM were 36.5% vs 1% in the identical sibling donor situation and 88% vs 12.5% in other donor-type transplants. We conclude that the degree of systemic inflammation, as reflected by CRP-levels, during the first 5-10 days after BMT identifies patients at risk of MTC and TRM. Our data may be useful in selecting patients for clinical trials involving pre-emptive anti-inflammatory treatment.

Risk assessment and risk-based therapeutic strategies in febrile neutropenia

Different approaches have developed over time regarding the empirical antimicrobial therapy of fever in neutropenic patients. The use of intravenous antibiotics remains the standard approach. Clinical criteria and 'low-risk' prediction rules have been developed that help select patients in whom oral therapy is well tolerated and who may be eligible for outpatient management. Comorbidity and clinical status at presentation remain important criteria in the risk-assessment process. Outpatient management requires additional assessment of non-medical criteria. Patients without documented infection and who have responded to initial therapy may benefit from simplified therapy such as a switch to oral drugs and/or outpatient management. Discontinuation of therapy may be considered in selected cases. Risk assessment in neutropenic patients with persistent unexplained fever is challenging. Available data suggest that broadening of the antibacterial coverage is of limited value. Instead, definition of the risk of fungal infection by using clinical criteria, imaging and laboratory studies, as well as the identification of those patients likely to benefit from antifungal therapy, appear to be of critical importance.