Annick Galetto-Lacour

Etiology of community-acquired pneumonia in hospitalized children based on WHO clinical guidelines

Community-acquired pneumonia (CAP) is a major cause of death in developing countries and of morbidity in developed countries. The objective of the study was to define the causative agents among children hospitalized for CAP defined by WHO guidelines and to correlate etiology with clinical severity and surrogate markers. Investigations included an extensive etiological workup. A potential causative agent was detected in 86% of the 99 enrolled patients, with evidence of bacterial (53%), viral (67%), and mixed (33%) infections. Streptococcus pneumoniae was accounted for in 46% of CAP. Dehydration was the only clinical sign associated with bacterial pneumonia. CRP and PCT were significantly higher in bacterial infections. Increasing the number of diagnostic tests identifies potential causes of CAP in up to 86% of children, indicating a high prevalence of viruses and frequent co-infections. The high proportion of pneumococcal infections re-emphasizes the importance of pneumococcal immunization.

Usefulness of procalcitonin and C-reactive protein rapid tests for the management of children with urinary tract infection

BACKGROUND Urinary tract infection (UTI) is a common problem in children. Because clinical findings and commonly used blood indices are nonspecific, the distinction between lower and upper urinary tract infection cannot be made easily in this population. However, this distinction is important because renal infection can induce parenchymal scarring. The objective of this study was to determine the accuracy of procalcitonin (PCT) compared with C-reactive protein (CRP) rapid tests to predict renal involvement in children with febrile UTI. METHODS PCT and CRP were measured in the blood of children admitted to the emergency room with fever, signs and symptoms of urinary tract infection and/or a positive urine dipstick analysis. Renal parenchymal involvement was assessed by a 99mTc-labeled dimercaptosuccinic acid renal scan in the acute phase of infection in all children. Sensitivity, specificity and likelihood ratios were determined for both tests. RESULTS Fifty-four children with a proven urinary tract infection were enrolled: 63% had renal involvement; and 37% had infection restricted to the lower urinary tract. No difference was found for age, sex and total white blood cell count between the groups. The calculated likelihood ratios of procalcitonin and C-reactive protein rapid tests were between 3.8 and 7 and 1.5 and 2.8, respectively. A positive PCT value predicted renal involvement in 87 to 92% of children with febrile UTI, compared with 44 to 83% using CRP values. CONCLUSIONS A rapid determination of procalcitonin concentration could be useful for the management of children with febrile UTI in the emergency room.

Serum Procalcitonin Level and Other Biological Markers to Distinguish Between Bacterial and Aseptic Meningitis in Children: A European Multicenter Case Cohort Study

OBJECTIVE To validate procalcitonin (PCT) level as the best biological marker to distinguish between bacterial and aseptic meningitis in children in the emergency department. DESIGN Secondary analysis of retrospective multicenter hospital-based cohort studies. SETTING Six pediatric emergency or intensive care units of tertiary care centers in 5 European countries. PARTICIPANTS Consecutive children aged 29 days to 18 years with acute meningitis. MAIN OUTCOME MEASURES Univariate analysis and meta-analysis to compare the performance of blood parameters (PCT level, C-reactive protein level, white blood cell count, and neutrophil count) and cerebrospinal fluid parameters (protein level, glucose level, white blood cell count, and neutrophil count) quickly available in the emergency department to distinguish early on between bacterial and aseptic meningitis. RESULTS Of 198 patients analyzed, 96 had bacterial meningitis. Sensitivity of cerebrospinal fluid Gram staining was 75%. The PCT level had significantly better results than the other markers for area under the receiver operating characteristic curve (0.98; 95% confidence interval, 0.95-0.99; P = .001). At a 0.5-ng/mL threshold, PCT level had 99% sensitivity (95% confidence interval, 97%-100%) and 83% specificity (95% confidence interval, 76%-90%) for distinguishing between bacterial and aseptic meningitis. The diagnostic odds ratio between high PCT level and bacterial meningitis was 139 (95% confidence interval, 39-498), without significant heterogeneity between centers. CONCLUSIONS The PCT level is a strong predictor for distinguishing between bacterial and aseptic meningitis in children in the emergency department. Its combination with other parameters in an effective clinical decision rule could be helpful.

Distinguishing between bacterial and aseptic meningitis in children: European comparison of two clinical decision rules

Background Clinical decision rules (CDRs) could be helpful to safely distinguish between bacterial and aseptic meningitis (AM). Objective To compare the performance of two of these CDRs for children: the Bacterial Meningitis Score (BMS) and the Meningitest. Design Secondary analysis of retrospective multicentre hospital-based cohort study. Setting Six paediatric emergency or intensive care units of tertiary care centres in five European countries. Patients Consecutive children aged 29 days to 18 years presenting with acute meningitis and procalcitonin (PCT) measurement. Intervention None. Main outcome measures The sensitivity and specificity of the BMS (start antibiotics in case of seizure, positive cerebrospinal fluid (CSF) Gram staining, blood neutrophil count ≥10 ×109/l, CSF protein level ≥80 mg/dl or CSF neutrophil count ≥1000 ×106/l) and the Meningitest (start antibiotics in case of seizure, purpura, toxic appearance, PCT level ≥0.5 ng/ml, positive CSF Gram staining or CSF protein level ≥50 mg/dl) were compared using a McNemar test. Results 198 patients (mean age 4.8 years) from six centres in five European countries were included; 96 had bacterial meningitis. The BMS and Meningitest both showed 100% sensitivity (95% CI 96% to 100%). The BMS had a significantly higher specificity (52%, 95% CI 42% to 62% vs 36%, 95% CI 27% to 46%; p<10−8). Conclusion The Meningitest and the BMS were both 100% sensitive. This result provides level II evidence for the sensitivity of both rules, which can be used cautiously. However, use of the BMS could safely avoid significantly more unnecessary antibiotic treatments for children with AM than can the Meningitest in this population.

Procalcitonin is a Predictor for High-Grade Vesicoureteral Reflux in Children: Meta-Analysis of Individual Patient Data

OBJECTIVE To assess the predictive value of procalcitonin, a serum inflammatory marker, in the identification of children with first urinary tract infection (UTI) who might have high-grade (≥3) vesicoureteral reflux (VUR). STUDY DESIGN We conducted a meta-analysis of individual data, including all series of children aged 1 month to 4 years with a first UTI, a procalcitonin (PCT) level measurement, cystograms, and an early dimercaptosuccinic acid scan. RESULTS Of the 152 relevant identified articles, 12 studies representing 526 patients (10% with VUR ≥3) were included. PCT level was associated with VUR ≥3 as a continuous (P = .001), and as a binary variable, with a 0.5 ng/mL preferred threshold (adjusted OR, 2.5; 95% CI, 1.1 to 5.4). The sensitivity of PCT ≥0.5 ng/mL was 83% (95% CI, 71 to 91) with 43% specificity rate (95% CI, 38 to 47). In the subgroup of children with a positive results on dimercaptosuccinic acid scan, PCT ≥0.5 ng/mL was also associated with high-grade VUR (adjusted OR, 4.8; 95% CI, 1.3 to 17.6). CONCLUSIONS We confirmed that PCT is a sensitive and validated predictor strongly associated with VUR ≥3, regardless of the presence of early renal parenchymal involvement in children with a first UTI.

Validation of a laboratory risk index score for the identification of severe bacterial infection in children with fever without source

Objective The identification of severe bacterial infection (SBI)in children with fever without source (FWS) remains a diagnostic problem. The authors previously developed in their Swiss population a risk index score, called the Lab-score, associating three independent predictors of SBI, namely C reactive protein (CRP), procalcitonin (PCT) and urinary dipstick. The objective of this study was to validate the Lab-score in a population of children with FWS different from the derivation model. Methods A prospective study, conducted in Padova, on 408 children aged 7 days to 36 months with FWS was recently published. PCT, CRP, white blood cell count (WBC) and urinary dipstick were determined in all children. The Lab-score was applied to this population and the diagnostic characteristics for the detection of SBI were calculated for the Lab-score and for any single variable used in the Italian study. Results For the identification of SBI, the sensitivity of a score ≥3 was 86% (95% CI 77% to 92%) and the specificity 83% (95% CI 79% to 87%). The area under the receiver operating characteristic curve for the Lab-score (0.91) was significantly superior to that of any single variable: 0.71 for WBC, 0.86 for CRP and 0.84 for PCT. The Lab-score performed better than other laboratory markers, even when applied to children of different age groups (<3 months, 3–12 months and >12 months). The results obtained in this validation set population were comparable with those of the derivation set population. Conclusions This study validated the Lab-score as a valuable tool to identify SBI in children with FWS.

Impact of procalcitonin on the management of children aged 1 to 36 months presenting with fever without source: A randomized controlled trial

OBJECTIVE The aim of the study was to evaluate the impact of procalcitonin (PCT) measurement on antibiotic use in children with fever without source. METHOD Children aged 1 to 36 months presenting to a pediatric emergency department (ED) with fever and no identified source of infection were eligible to be included in a randomized controlled trial. Patients were randomly assigned to 1 of 2 groups as follows: PCT+ (result revealed to the attending physician) and PCT- (result not revealed). Patients from both groups also had complete blood count, blood culture, urine analysis, and culture performed. Chest radiography or lumbar puncture could be performed if required. RESULTS Of the 384 children enrolled and equally randomized into the PCT+ and PCT- groups, 62 (16%) were diagnosed with a serious bacterial infection (urinary tract infection, pneumonia, occult bacteremia, or bacterial meningitis) by primary ED investigation. Ten were also found to be neutropenic (<500 x 10(6)/L). Of the remaining undiagnosed patients, 14 (9%) of 158 received antibiotics in the PCT+ group vs 16 (10%) of 154 in the PCT- group (Delta -2%; 95% confidence interval [CI], -8 to 5). A strategy to treat all patients with PCT of 0.5 ng/mL or greater with prophylactic antibiotic in this group of patients would have resulted in an increase in antibiotic use by 24% (95% CI, 15-33). CONCLUSION Semiquantitative PCT measurement had no impact on antibiotic use in children aged 1 to 36 months who presented with fever without source. However, a strategy to use prophylactic antibiotics in all patients with abnormal PCT results would have resulted in an increase use of antibiotics.

Do Children with Uncomplicated Severe Acute Malnutrition Need Antibiotics? A Systematic Review and Meta-Analysis

Background Current (1999) World Health Organization guidelines recommend giving routine antibiotics (AB) for all children with severe acute malnutrition (SAM), even if they have uncomplicated disease with no clinically obvious infections. We examined the evidence behind this recommendation. Methods and Findings OVID-MEDLINE, EMBASE, COCHRANE, GLOBAL-HEALTH, CINAHL, POPLINE, AFRICA-WIDE-NiPAD, and LILACS were searched for AB efficacy, bacterial resistance, and infection rates in SAM. Following PRISMA guidelines, a systematic review and meta-analysis were performed. Three randomised controlled trials (RCT), five Cochrane reviews, and 37 observational studies were identified. One cohort-study showed no increase in nutritional-cure and mortality in uncomplicated SAM where no AB were used. (p>0.05). However, an unpublished RCT in this setting did show mortality benefits. Another RCT did not show superiority of ceftriaxone over amoxicilllin for these same outcomes, but adressed SAM children with and without complications (p = 0.27). Another RCT showed no difference between amoxicillin and cotrimoxazole efficacies for pneumonia in underweight, but not SAM. Our meta-analysis of 12 pooled susceptibility-studies for all types of bacterial isolates, including 2767 stricly SAM children, favoured amoxicillin over cotrimoxazole for susceptibility medians: 42% (IQR 27–55%) vs 22% (IQR 17–23%) and population-weighted-means 52.9% (range 23–57%) vs 35.4% (range 6.7–42%). Susceptibilities to second-line AB were better, above 80%. Prevalence of serious infections in SAM, pooled from 24 studies, ranged from 17% to 35.2%. No study infered any association of infection prevalence with AB regimens in SAM. Conclusions The evidence underlying current antibiotic recommendations for uncomplicated SAM is weak. Susceptibility-studies favour amoxicillin over cotrimoxazole. However, given that these antibiotics have side-effects, costs, and risks as well as benefits, their routine use needs urgent testing. With reliable monitoring, we believe that there is sufficient equipoise for placebo controlled RCTs, the only robust way to demonstrate true efficacy.

Elevated inflammatory markers combined with positive pneumococcal urinary antigen are a good predictor of pneumococcal community-acquired pneumonia in children.

Background: Our objective was to evaluate procalcitonin (PCT) and C-reactive protein (CRP) as predictors of a pneumococcal etiology in community-acquired pneumonia (CAP) in hospitalized children. Methods: Children requiring hospitalization for CAP were prospectively enrolled. The following indices were determined: antibodies against pneumococcal surface proteins (anti-PLY, pneumococcal histidine triad D, pneumococcal histidine triad E, LytB and pneumococcal choline-binding protein A), viral serology, nasopharyngeal cultures and polymerase chain reaction for 13 respiratory viruses, blood pneumococcal polymerase chain reaction, pneumococcal urinary antigen, PCT and CRP. Presumed pneumococcal CAP (P-CAP) was defined as a positive blood culture or polymerase chain reaction for Streptococcus pneumoniae or as a pneumococcal surface protein seroresponse (≥2-fold increase). Results: Seventy-five patients were included from which 37 (49%) met the criteria of P-CAP. Elevated PCT and CRP values were strongly associated with P-CAP with odds ratios of 23 (95% confidence interval: 5–117) for PCT and 19 (95% confidence interval: 5–75) for CRP in multivariate analysis. The sensitivity was 94.4% for PCT (cutoff: 1.5 ng/mL) and 91.9% for CRP (cutoff: 100 mg/L). A value ⩽0.5 ng/mL of PCT ruled out P-CAP in >90% of cases (negative likelihood ratio: 0.08). Conversely, a PCT value ≥1.5 ng/mL associated with a positive pneumococcal urinary antigen had a diagnostic probability for P-CAP of almost 80% (positive likelihood ratio: 4.59). Conclusions: PCT and CRP are reliable predictors of P-CAP. Low cutoff values of PCT allow identification of children at low risk of P-CAP. The association of elevated PCT or CRP with a positive pneumococcal urinary antigen is a strong predictor of P-CAP.

Immunity to pneumococcal surface proteins in children with community‐acquired pneumonia: a distinct pattern of responses to pneumococcal choline‐binding protein A

The aetiological diagnosis of community-acquired pneumonia (CAP) is challenging in children, and serological markers would be useful surrogates for epidemiological studies of pneumococcal CAP. We compared the use of anti-pneumolysin (Ply) antibody alone or with four additional pneumococcal surface proteins (PSPs) (pneumococcal histidine triad D (PhtD), pneumococcal histidine triad E (PhtE), LytB, and pneumococcal choline-binding protein A (PcpA)) as serological probes in children hospitalized with CAP. Recent pneumococcal exposure (positive blood culture for Streptococcus pneumoniae, Ply(+) blood PCR finding, and PSP seroresponse) was predefined as supporting the diagnosis of presumed pneumococcal CAP (P-CAP). Twenty-three of 75 (31%) children with CAP (mean age 33.7 months) had a Ply(+) PCR finding and/or a ≥ 2-fold increase of antibodies. Adding seroresponses to four PSPs identified 12 additional patients (35/75, 45%), increasing the sensitivity of the diagnosis of P-CAP from 0.44 (Ply alone) to 0.94. Convalescent anti-Ply and anti-PhtD antibody titres were significantly higher in P-CAP than in non P-CAP patients (446 vs. 169 ELISA Units (EU)/mL, p 0.031, and 189 vs. 66 EU/mL, p 0.044), confirming recent exposure. Acute anti-PcpA titres were three-fold lower (71 vs. 286 EU/mL, p <0.001) in P-CAP children. Regression analyses confirmed a low level of acute PcpA antibodies as the only independent predictor (p 0.002) of P-CAP. Novel PSPs facilitate the demonstration of recent pneumococcal exposure in CAP children. Low anti-PcpA antibody titres at admission distinguished children with P-CAP from those with CAP with a non-pneumococcal origin.