Significance of platelet count in children admitted with bronchiolitis

Abstract

AIMTo determine the true prevalence of thrombocytosis in children less than 2 years of age with bronchiolitis, its association with risk factors, disease severity and thromboembolic complications.METHODSA retrospective observational medical chart review of 305 infants aged two years or less hospitalized for bronchiolitis. Clinical outcomes included disease severity, duration of hospital stay, admission to pediatric intensive care unit, or death. They also included complications of thrombocytosis, including thromboembolic complications such as cerebrovascular accident, acute coronary syndrome, deep venous thrombosis, pulmonary embolus, mesenteric thrombosis and arterial thrombosis and also hemorrhagic complications such as bleeding (spontaneous hemorrhage in the skin, mucous membranes, gastrointestinal, respiratory, or genitourinary tracts).RESULTSThe median age was 4.7 mo and 179 were males (59%). Respiratory syncytial virus was isolated in 268 (84%), adenovirus in 23 (7%) and influenza virus A or B in 13 (4%). Thrombocytosis (platelet count > 500 × 109/L) occurred in 88 (29%; 95%CI: 24%-34%), more commonly in younger infants with the platelet count declining with age. There was no significant association with the duration of illness, temperature on admission, white blood cell count, serum C-reactive protein concentration, length of hospital stay or admission to the intensive care unit. No death, thrombotic or hemorrhagic events occurred.CONCLUSIONThrombocytosis is common in children under two years of age admitted with bronchiolitis. It is not associated with disease severity or thromboembolic complications.

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

“…We first compared the clinical characteristics between the patients with thrombocytosis and the patients with a normal platelet count on admission. We validated the findings of a previous report that the patients with thrombocytosis were younger than the patients with a normal platelet count and that there was no difference in disease severity between the two groups [9]. It has been reported previously that the platelet count peaks during the second and third weeks of the illness [21].…”

“…The delta platelet count of 50 × 10 9 /L was determined as the cut-off value for the three groups to minimize the chance of misclassification of patients according to known normal variability of platelet counts measured by the counter (XE2000i, Sysmex, Japan) [15][16][17]. Thrombocytosis was defined as a platelet count > 500 × 10 9 /L, according to the relevant studies [9,11]. Fever was defined as an axillary temperature exceeding 38.0 °C.…”

“…Previous studies on pediatric patients with bronchiolitis have focused on single platelet count determinations at hospital admission, and these studies found that the prevalence of thrombocytosis on admission ranged from 22.7% to 38.6% among consecutive patients with bronchiolitis [9][10][11]. The association between thrombocytosis on admission and disease severity in patients with bronchiolitis has been studied [9]. However, the average life span of platelets in blood is 7-10 days.…”

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

“…Al Shibli et al. [ 18 ] reported that among children with bronchiolitis, elevation in platelet count (thrombocytosis) is a common presentation; however, it is not associated with disease severity or complications. On the contrary, sepsis is also defined as a critical thrombocytopenic disease in a number of studies [ 19 ].…”

Brain Complications with Influenza Infection in Children

“…In clinical practice, if patients with influenza infection appear facial paralysis, limb movement disorders, sensory disorders, aphasia, consciousness disorders and/or accompanied by hypertension, diabetes, and the laboratory is clear influenza virus infection, at the same time with increased fibrinogen, attention should be paid to the occurrence of cerebral infarction or cerebrovascular disease. Some children with influenza also experienced complications of thrombocytosis, including cerebrovascular accident, acute coronary syndrome, deep venous thrombosis, pulmonary embolus, mesenteric thrombosisand arterial thrombosis and also hemorrhagic complications[80].…”