Antioxidant protection against iron in children with meningococcal sepsis.
OBJECTIVE
To assess antioxidant protection against iron-catalyzed reactive oxygen species in meningococcal sepsis and to establish whether severity of illness is related to deficiencies in these antioxidant systems.


METHODS
Prospective, controlled study.


METHODS
Pediatric intensive care unit of a postgraduate teaching hospital.


METHODS
Twenty children aged 6 months to 15 yrs (median, 5 yrs) with meningococcal septic shock were studied. Paired convalescent samples taken 8-10 wks after discharge were available in nine children.


METHODS
Routine management for meningococcal sepsis.


RESULTS
Patients were classified for disease severity using the Glasgow Meningococcal Septicaemia Prognostic Score. Paired acute and convalescent samples were compared. Transferrin level (1.77 +/- 0.08 g/L) and total iron-binding capacity (46.2 +/- 2.0 microM) were significantly decreased in acute patients compared with paired convalescent samples (2.85 +/- 0.10 g/L and 74.4 +/- 2.5 microM, respectively; p <.0001). The iron saturation of transferrin was significantly increased in acute disease (36.9% +/- 2.5%) compared with convalescence (18.8% +/- 1.5%; p =.0003). Iron-binding antioxidant protection was not significantly different in acute (81.4% +/- 1.7%) and paired convalescent samples (85.6% +/- 2.5%; p =.54). However, patients with more severe meningococcal septicemia (GMSPS, >10; n = 12) had significantly diminished protection (77.5% +/- 2.4%) compared with less severe disease (87.1% +/- 1.6%; p =.0028), and there was a significant correlation between disease severity and iron-binding antioxidant protection (R =.48; p =.00067) in acute disease. Paired ceruloplasmin levels were available in six patients and were decreased in acute disease (0.29 +/- 0.02 g/L) compared with convalescence (0.40 +/- 0.04 g/L), although not statistically significant (p =.076). However, there was a significant correlation between plasma ceruloplasmin and disease severity (Pearson product moment correlation, p =.038) in the acute patients. Iron-oxidizing antioxidant assays were performed in four paired samples and were diminished in acute patients (53.3 +/- 4.4%) compared with convalescence (67.8 +/- 3.2%; p =.015). Acute samples demonstrated a significant relationship between iron-oxidizing antioxidant protection and both disease severity (r =.30; p =.012) and plasma ceruloplasmin levels (r =.48; p =.00067).


CONCLUSIONS
Children with meningococcal septicemia exhibit abnormal plasma iron chemistry and decreased protection against iron-catalyzed oxidative damage. Such deficiencies correlate with disease severity.
Paediatric Intensive Care Unit, Imperial College School of Medicine at St Mary's Hospital, London, UK.
Marino
M
Festa
Sharon
S
Mumby
Simon
S
Nadel
John M C
JM
Gutteridge
Gregory J
GJ
Quinlan
D000208:Acute Disease; D000293:Adolescent; D000975:Antioxidants / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007501:Iron / Q000097:blood*; D008297:Male; D008589:Meningococcal Infections / Q000097:blood*; D011446:Prospective Studies; D017382:Reactive Oxygen Species / Q000097:blood*; D018805:Sepsis / Q000097:blood*
D000975:Antioxidants; D017382:Reactive Oxygen Species; D007501:Iron