Eosinophils and eosinophil-derived proteins in children with moderate asthma

Abstract

E Eo os si in no op ph hi il ls s a an nd d e eo os si in no op ph hi il l--d de er ri iv ve ed d p pr ro ot te ei in ns s i in n cThe number of eosinophils, serum ECP and EDN, and urinary EDN were determined in 22 children with stable, allergic asthma, aged 4-14 yrs, and in 17 agematched healthy controls. Symptoms were monitored, the peak expiratory flow rate (PEFR) was recorded in the younger children, and lung function tests (forced expiratory volume in one second (FEV1) and the provocative concentration of histamine causing a 20% fall in FEV1 (PC20)) were performed in the older children. None of the asthmatic children had respiratory symptoms. PEFR was not significantly different in asthmatic children compared to controls. The FEV1 % predicted was significantly lower compared to controls.The number of eosinophils, serum ECP and EDN, and urinary EDN were significantly higher in asthmatic children compared with controls. After correction of serum ECP and EDN, and urinary EDN for the number of eosinophils, the differences between patients and controls disappeared. The nocturnal PEFR and the FEV1 were significantly related to urinary EDN.The results suggest that serum and urinary concentration of eosinophil-derived proteins can be determined instead of the number of eosinophils to support the diagnosis of asthma in childhood. The urinary concentration of eosinophil-derived neurotoxin can be especially valuable in young children, because in this age group quantification of lung function cannot be performed and blood sampling can be difficult.

Circadian Variation of Exhaled Nitric Oxide and Urinary Eosinophil Protein X in Asthmatic and Healthy Children

“…EPX is released by activated eosinophils into the tissue and circulation, and can be detected in urine (8), whereas NO is released by an inducible calcium-independent NO synthase during airway inflammation and can be detected in exhaled air (9). It has been observed that levels of urinary EPX and exhaled NO are higher in asthmatic individuals than healthy control subjects (7,10,11). In addition, close correlations have been seen between levels of eosinophil cationic protein in sputum and both urinary EPX and FeNo (12).…”

Influence of different dosage schedules of inhaled fluticasone propionate on peripheral blood cytokine concentrations in childhood asthma

“…The number of eosinophils was counted with a Coulter counting chamber. ECP levels were determined as published previously [11]. Briefly, blood was allowed to clot during 1 h after it was drawn.…”

Urinary Eosinophil Protein X in Childhood Asthma: Relation with Changes in Disease Control and Eosinophilic Airway Inflammation

“…Elevated uEPX has been reported in asthmatics with or without allergy [3, 4], with great overlap between healthy controls and asthmatics [5, 6]. A relation with asthma symptoms and lung function has been shown, and uEPX increases significantly during asthma exacerbations [7–9].…”