The neuroendocrine stress response and severity of acute respiratory syncytial virus bronchiolitis in infancy.
OBJECTIVE
Neuroendocrine hormones have profound effects on the immune system. The immune response is a major factor in the pathogenesis of acute respiratory syncytial virus (RSV) infection. We hypothesised that there is a relationship between the neuroendocrine response in acute RSV infection, the severity of illness, and the degree of lymphopenia.


METHODS
Prospective, non-randomised cohort study of infants hospitalised for RSV infection requiring mechanical ventilation or managed conservatively. The study assessed the effect of age, gender, birth gestation, and severity of illness on stress hormone profile and its relationship to lymphocyte count.


METHODS
Regional Paediatric Intensive Care Unit (PICU) and children's wards.


METHODS
Thirty-two consecutive infants with RSV infection were enrolled, of which thirteen were mechanically ventilated on PICU (study subjects) and nineteen treated on the ward (comparison group). Twenty-three children (72%) returned for follow-up.


RESULTS
A specific neuroendocrine profile was found in PICU patients compared to ward patients (Wilks Lambda = 0.36, F = 9.05, P =.03). PICU patients had significantly higher prolactin and growth hormone, and significantly lower leptin and IGF-1. Cortisol levels were the same. PICU patients were more lymphopenic compared to ward patients (P =.0001). On multiple regression analysis, prolactin and leptin levels accounted for 57% of the variation in lymphocyte count.


CONCLUSIONS
Whereas the effect of intensive care (mechanical ventilation and medication) could not be controlled for, our results suggest that there is an association between the neuroendocrine hormone response, severity of illness and degree of lymphopenia.
Tasker
Robert C
RC
Department of Paediatrics, Addenbrooke's Hospital, University of Cambridge, Hills Road, Box 181, Cambridge, CB2 2QQ, UK.
Roe
Michael F E
MF
Bloxham
David M
DM
White
Deborah K
DK
Ross-Russell
Robert I
RI
O'Donnell
D Roddy
DR
D000208:Acute Disease; D000704:Analysis of Variance; D001988:Bronchiolitis / Q000097:blood* / Q000145:classification / Q000628:therapy; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007223:Infant; D015278:Intensive Care Units, Pediatric; D020738:Leptin / Q000097:blood*; D008231:Lymphopenia / Q000097:blood*; D008297:Male; D015213:Neuroimmunomodulation / Q000276:immunology*; D009490:Neurosecretory Systems / Q000378:metabolism*; D011388:Prolactin / Q000097:blood*; D012121:Respiration, Artificial; D018357:Respiratory Syncytial Virus Infections / Q000097:blood* / Q000145:classification / Q000628:therapy; D012720:Severity of Illness Index
D020738:Leptin; D011388:Prolactin; D006854:Hydrocortisone