Non-enteropathic hemolytic uremic syndrome: causes and short-term course.
BACKGROUND
Nondiarrheal or Streptococcus pneumoniae-related hemolytic uremic syndrome (HUS) represents a heterogeneous group of disorders. This study was performed to: (1) describe the current incidence, causes, demographic features, hospital courses, and short-term outcomes of non-enteropathic HUS; (2) compare findings in patients with non-enteropathic HUS with those obtained from a contemporaneous cohort of children with enteropathic or diarrhea-associated HUS (D+ HUS) diagnosed and treated at the same clinical sites; and (3) identify clinical or laboratory features that differentiate these 2 groups and predict disease severity and the short-term outcome in patients with non-enteropathic HUS.


METHODS
Data were collected from patients screened between 1997 and 2001 for enrollment in a multicenter trial of SYNSORB Pk (SYNSORB Biotech Inc, Calgary, Alberta, Canada) in D+ HUS, but who were ineligible because of lack of a diarrhea prodrome. The following features were recorded: age; sex; ethnicity; prodromal symptoms; cause; nadir values for hemoglobin, hematocrit, and platelet count; use of dialysis; and length of hospitalization.


RESULTS
Twenty-seven of 247 children with HUS had non-enteropathic HUS (11%). Twenty-four patients (15 boys, 9 girls), whose medical records were complete and available for review, comprise the study cohort. Mean age at onset was 4.2 +/- 0.9 (SE) years. Infection caused by S pneumoniae was diagnosed in 9 patients (38%). Dialysis was performed in 17 patients (71%) for 40 +/- 27 days. Median length of hospitalization was 22 days (range, 2 to 71 days). Children with S pneumoniae-related HUS had a longer hospital stay than those with other causes of non-enteropathic HUS, but all patients with S pneumoniae-related HUS recovered kidney function. Dialysis therapy was required more often (17 of 24 versus 59 of 145 children; P = 0.025) and hospital stays were longer (median, 22 versus 9 days; P = 0.002) in children with non-enteropathic HUS compared with patients with D+ HUS who were enrolled in the SYNSORB Pk clinical trial.


CONCLUSIONS
(1) The incidence of non-enteropathic HUS is approximately one tenth that of D+ HUS; (2) patients with non-enteropathic HUS require dialysis therapy more often and are hospitalized more than twice as long during the acute episode compared with those with D+ HUS; (3) infection caused by S pneumoniae accounts for nearly 40% of cases of non-enteropathic HUS; and (4) although S pneumoniae-related HUS is associated with a less favorable short-term course than other types of non-enteropathic HUS or D+ HUS, the long-term prognosis for recovery of renal function appears to be good in these patients.
Constantinescu
Alex R
AR
Division of Pediatric Nephrology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick, NJ, USA.
Bitzan
Martin
M
Weiss
Lynne S
LS
Christen
Erica
E
Kaplan
Bernard S
BS
Cnaan
Avital
A
Trachtman
Howard
H
D000293:Adolescent; D017668:Age of Onset; D002170:Canada; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003967:Diarrhea / Q000150:complications; D005260:Female; D006463:Hemolytic-Uremic Syndrome / Q000188:drug therapy / Q000453:epidemiology* / Q000208:ethnology / Q000628:therapy; D006801:Humans; D007223:Infant; D007668:Kidney / Q000473:pathology / Q000601:surgery; D016030:Kidney Transplantation / Q000379:methods; D008297:Male; D006435:Renal Dialysis / Q000379:methods; D051437:Renal Insufficiency / Q000209:etiology / Q000628:therapy; D013296:Streptococcus pneumoniae / Q000302:isolation & purification