Significance of platelet count in children admitted with bronchiolitis

Bronchiolitis Severity Affects Blood Count and Inflammatory Marker Levels: A Real-Life Experience

BACKGROUND

Bronchiolitis is the most common cause of lower respiratory tract infection (LRTI) in the first year of life. We analyzed the association between complete blood count (CBC), c-reactive protein (CRP), and novel inflammatory indexes (NLR, PLR, MLR, ELR, LMR, NPR, LPR, LNR, PNR, SII, SIRI) in predicting bronchiolitis severity at hospital admission.

METHODS

We retrospectively collected data from 95 infants hospitalized for bronchiolitis in a third-level hospital during three epidemic seasons. Five outcomes of severity were analyzed: BRAS; pediatric intensive care unit (PICU) admission; ventilatory support; intravenous (IV) rehydration; and length of stay (LOS).

RESULTS

Lower age and weight at admission were statistically associated with four of the five severity outcomes. Prolonged LOS (≥6 days) was associated with high values of total white blood cells, lymphocytes, and eosinophils. Only three inflammatory indexes (PLR, MLR, and PNR) showed a significant association with one outcome (prolonged LOS). A new index (RBC/AiW/1000) was statistically associated with each severity outcome for a value > 350.

CONCLUSIONS

We proposed a comprehensive analysis of the association between CBC, CRP, and novel inflammatory indexes and bronchiolitis severity. RBC/AiW/1000 could represent a future predictive marker of disease severity at hospital admission in infants with bronchiolitis.

Platelet count and risk of severe illness in hospitalised children with Influenza-Like illness

AIM

To examine the clinical significance of thrombocytosis (platelets > 500 × 109 /L) in admitted children with an influenza-like illness.

METHODS

We performed a database analysis consisting of patients evaluated at our medical centers with an influenza-like illness between 2009 and 2013. We included paediatric patients and examined the association between platelet count, respiratory viral infections, and admission outcomes (hospital length of stay and admission to the paediatric intensive care unit) using regression models adjusting for multiple variables.

RESULTS

A total of 5171 children were included in the study cohort (median age 0.8 years; interquartile range, 0.2-1.8; 58% male). Younger age, and not the type of viral infection, was associated with a high platelet count (p < 0.001). Elevated platelet count independently predicted admission outcomes (p ≤ 0.05). The presence of thrombocytosis was associated with an increased risk for a prolonged length of stay (odds ratio = 1.2; 95% Confidence interval = 1.1 to 1.4; p = 0.003) and admission to the paediatric intensive care unit (odds ratio = 1.5; 95% Confidence interval = 1.1 to 2.0; p = 0.002).

CONCLUSION

In children admitted with an influenza-like illness, a high platelet count is an independent predictor of admission outcomes. Platelet count may be used to improve risk assessment and management decisions in these paediatric patients.

Binding of respiratory syncytial virus particles to platelets does not result in their degranulation in vitro

Respiratory syncytial virus (RSV) is a major cause of severe respiratory infection in infants and the elderly. The mechanisms behind severe RSV disease are incompletely understood, but a dysregulated immune response probably plays an important role. Platelets are increasingly being recognized as immune cells and are involved in the pathology of several viruses. The release of chemokines from platelets upon activation may attract, for example, neutrophils to the site of infection, which is a hallmark of RSV pathology. In addition, since RSV infections are sometimes associated with cardiovascular events and platelets express several known RSV receptors, we investigated the effect of RSV exposure on platelet degranulation. Washed human platelets were incubated with sucrose-purified RSV particles. P-selectin and CD63 surface expression and CCL5 secretion were measured to assess platelet degranulation. We found that platelets bind and internalize RSV particles, but this does not result in degranulation. Our results suggest that platelets do not play a direct role in RSV pathology by releasing chemokines to attract inflammatory cells.

Thrombocytopenia in Virus Infections

Thrombocytopenia, which signifies a low platelet count usually below 150 × 10⁹/L, is a common finding following or during many viral infections. In clinical medicine, mild thrombocytopenia, combined with lymphopenia in a patient with signs and symptoms of an infectious disease, raises the suspicion of a viral infection. This phenomenon is classically attributed to platelet consumption due to inflammation-induced coagulation, sequestration from the circulation by phagocytosis and hypersplenism, and impaired platelet production due to defective megakaryopoiesis or cytokine-induced myelosuppression. All these mechanisms, while plausible and supported by substantial evidence, regard platelets as passive bystanders during viral infection. However, platelets are increasingly recognized as active players in the (antiviral) immune response and have been shown to interact with cells of the innate and adaptive immune system as well as directly with viruses. These findings can be of interest both for understanding the pathogenesis of viral infectious diseases and predicting outcome. In this review, we will summarize and discuss the literature currently available on various mechanisms within the relationship between thrombocytopenia and virus infections.

The implications of platelet count changes during hospitalization in the disease management of paediatric patients with bronchiolitis

BACKGROUND

The objective of this study was to investigate the significance of the platelet count on admission and platelet count changes during hospitalization in paediatric patients with bronchiolitis.

METHODS

Clinical data from 404 consecutive patients hospitalized for bronchiolitis were collected and compared after grouping according to the platelet count on admission and the delta platelet count during hospitalization (the platelet count 3-5 days after admission minus the platelet count on admission; Group A, delta platelet count < -50 × 10⁹/L; Group B, -50 × 10⁹/L ≤ delta platelet count ≤ 50 × 10⁹/L; Group C, delta platelet count > 50 × 10⁹/L).

RESULTS

Thrombocytosis was found in 79 (19.6%) patients, while 325 (80.4%) patients had a normal platelet count on admission. There was no difference in disease severity between these two groups. Groups A, B and C comprised 57 (14.1%), 133 (32.9%) and 214 (53.0%) patients, respectively. The patients from Group A had longer periods of oxygen therapy and stay in the paediatric intensive care unit, and a greater frequency of mechanical ventilation than the patients from Group B or Group C (all p < .05). Notably, among all the patients, the delta platelet count negatively correlated with the numbers of days of oxygen therapy (r = -0.385, p < .001) and stay in the paediatric intensive care unit (r = -0.603, p < .001).

CONCLUSIONS

A decrease in the platelet count during hospitalization in paediatric patients with bronchiolitis may provide useful information for disease management.

Evaluation of platelet count, erythrocyte sedimentation rate and C-reactive protein levels in paediatric patients with inflammatory and infectious disease

Inflammatory and infectious diseases are the major causes of morbidity and mortality. The identification of markers for the assessment of disease activity and response to treatment can improve long-term prognosis. The aim of this study was to evaluate platelet count, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) among children with inflammatory and infectious disease. This cross-sectional study was conducted in the paediatric immunology and infectious units of Shahid Madani Hospital of Khorramabad. One hundred fifty children, half boys and half girls, with diagnoses of infectious and inflammatory diseases were included in the study. Platelet count, ESR and CRP were measured at the time of hospitalization and thereafter (recovery phase). A questionnaire including demographic information, diagnosis and paraclinical data was completed. At the time of hospitalization, all 150 children had abnormal ESR, 110 (73.3%) had abnormal CRP and 12 (92%) had alterations in platelet count. At the time of discharge, one patient (0.7%) had normal ESR, 132 (88%) had normal CRP and 140 patients (93.3%) had normal platelet count. At the time of discharge, we found a significant difference between the levels of CRP and platelets in girls. This study showed that CRP level is useful during treatment follow-up. Changes in platelet count are likely to be more prevalent in girls.