Pediatric Investigators Collaborative Network on Infections in Canada Study of Respiratory Syncytial Virus-associated Deaths in Pediatric Patients in Canada, 2003-2013.

Background: Respiratory syncytial virus (RSV) is a major cause of pneumonia and bronchiolitis in children. Mortality rates in previously healthy children hospitalized with RSV are <0.5%, but up to 37% in patients with underlying medical conditions. The objective of this study was to characterize factors associated with deaths among children hospitalized with RSV infection in Canadian pediatric centers. Methods: A retrospective case series of children aged ≤18 years with RSV-associated deaths at centers affiliated with the Pediatric Investigators Collaborative Network on Infections in Canada from 2003­2013, inclusive, was performed [corrected]. Cases were identified using RSV-specific International Classification of Diseases codes to capture deaths where a diagnosis of RSV infection was present. Results: Eleven centers reported 79 RSV-associated deaths. RSV was regarded as primarily responsible for death in 32 cases (40.5%). Median age at death was 11 months (range, <1 month to 16 years). Thirty-nine patients (49.4%) were male. Fourteen patients (17.7%) had no known risk factors for severe RSV infection. Healthcare-associated RSV infections (HAIs) accounted for 29 deaths (36.7%), with RSV judged to be the primary cause of death in 9 of these cases. Conclusions: RSV-associated deaths were predominantly associated with chronic medical conditions and immunocompromised states among infants; however, 1 in 5 deaths occurred among patients with no known risk factors for severe RSV. Mortality associated with HAI accounted for over a third of cases. These findings highlight patient groups that should be targeted for RSV prevention strategies such as infection control practices, immunoprophylaxis, and future vaccination programs.

Multicenter assessment of quantitative sensory testing (QST) for the detection of neuropathic-like pain responses using the topical capsaicin model.

BACKGROUND: The use of quantitative sensory testing (QST) in multicenter studies has been quite limited, due in part to lack of standardized procedures among centers. AIM: The aim of this study was to assess the application of the capsaicin pain model as a surrogate experimental human model of neuropathic pain in different centers and verify the variation in reports of QST measures across centers. METHODS: A multicenter study conducted by the Quebec Pain Research Network in six laboratories allowed the evaluation of nine QST parameters in 60 healthy subjects treated with topical capsaicin to model unilateral pain and allodynia. The same measurements (without capsaicin) were taken in 20 patients with chronic neuropathic pain recruited from an independent pain clinic. RESULTS: Results revealed that six parameters detected a significant difference between the capsaicin-treated and the control skin areas: (1) cold detection threshold (CDT) and (2) cold pain threshold (CPT) are lower on the capsaicin-treated side, indicating a decreased in cold sensitivity; (3) heat pain threshold (HPT) was lower on the capsaicin-treated side in healthy subjects, suggesting an increased heat pain sensitivity; (4) dynamic mechanical allodynia (DMA); (5) mechanical pain after two stimulations (MPS2); and (6) mechanical pain summation after ten stimulations (MPS10), are increased on the capsaicin-treated side, suggesting an increased in mechanical pain (P < 0.002). CDT, CPT and HPT showed comparable effects across all six centers, with CPT and HPT demonstrating the best sensitivity. Data from the patients showed significant difference between affected and unaffected body side but only with CDT. CONCLUSION: These results provide further support for the application of QST in multicenter studies examining normal and pathological pain responses.

Contexte: L'utilisation de tests sensoriels quantitatifs (QST) dans les études multicentriques est limitée, en partie à cause de l'absence de procédures normalisées au sein des centres.But: évaluer l'application du modèle de la douleur traitée par capsaïcine en tant que modèle expérimental humain de substitution pour la douleur neuropathique dans différents centres et vérifier les variations dans les mesures des tests sensoriels quantitatifs entre les centres.Méthodes: Une étude multicentrique menée par le Réseau québécois de recherche sur la douleur dans six laboratoires a permis d'évaluer neuf paramètres de tests sensoriels quantitatifs chez 60 sujets en bonne santé traités par capsaïcine topique afin de modéliser la douleur unilatérale et l'allodynie. Les mêmes mesures (sans capsaïcine) ont été prises chez 20 patients atteints de douleur neuropathique chronique recrutés dans une clinique de la douleur indépendante.Résultats: Les résultats ont révélé une différence significative entre la zone de peau traitée à la capsaïcine et la zone contrôle pour six paramètres : 1) le seuil de détection du froid (CTF) et 2) le seuil de perception de la douleur causée par le froid (CPT) étaient plus bas sur le côté traité par capsaïcine chez les sujets en bonne santé, ce qui indique une diminution de la sensibilité au froid, 3) Le seuil de perception de la douleur causée par la chaleur (HPT) était plus bas sur le côté traité par capsaïcine chez les sujets en bonne santé, ce qui suggère une augmentation de la sensibilité à la douleur causée par la chaleur; 4) l'allodynie mécanique dynamique (DMA), 5) la douleur mécanique après deux stimulations (MPS2) et 6) la somme de la douleur mécanique après 10 stimulations (MPS10) ont augmenté sur le côté traité à la capsaïne, ce qui suggère une augmentation de la douleur mécanique (p < 0,002). Le CDT, le CPT et le HPT ont démontré des effets comparables dans les six centres, le CPT et le HPT démontrant la meilleure sensibilité. Les données des patients ont révélé une différence significative entre le côté affecté et le non côté non affecté, mais seulement dans le cas du CDT.Conclusion: Ces résultats soutiennent l'application de tests sensoriels quantitatifs dans les études multicentriques portant sur les réponses normales et pathologiques à la douleur.

Current methodological approaches in conditioned pain modulation assessment in pediatrics.

Conditioned pain modulation (CPM) paradigms have been used in various studies with healthy and non-healthy adult populations in an attempt to elucidate the mechanisms of pain processing. However, only a few studies so far have applied CPM in pediatric populations. Studies finding associations with chronic pain conditions suggest that deficiencies in underlying descending pain pathways may play an important role in the development and persistence of pain early in life. Twelve studies were identified using a PubMed search which examine solely pediatric populations, and these are reviewed with regard to demographics studied, methodological approaches, and conclusions reached. This review aimed to provide both clinicians and researchers with a brief overview of the current state of research regarding the use of CPM in children and adolescents, both healthy and clinical patients. The implications of CPM in experimental and clinical settings and its potential to aid in refining considerations to individualize treatment of pediatric pain syndromes will be discussed.