title: Clustering of post-diarrheal (Shiga toxin-mediated) hemolytic uremic syndrome in families.
abstract: OBJECTIVE
  1. To study the epidemiological and clinical features of Shiga toxin (Stx)-mediated (post-diarrheal) hemolytic uremic syndrome (HUS) occurring in more than 1 family member. 2. To compare familial with non-familial episodes, and concurrent familial with non-concurrent familial cases. 3. To determine the likelihood of Stx HUS occurring in a second family member.
  
  
  METHODS
  A retrospective review from January 1970 through September 2001 of families in whom Stx HUS occurred in more than 1 family member was conducted using a computerized HUS registry. It contains information on 373 episodes that occurred in 356 families from Utah and neighboring states. Cases were categorized as being either concurrent (i.e., occurring within a month of one another) or non-concurrent, and the study was limited to those with typical (post-diarrheal) episodes.
  
  
  RESULTS
  HUS occurred in 2 or more family members in 17 (4.8%) of the families in our registry. In 12 (3.4%) of these families episodes occurred with days to weeks of each other; in 5 families (1.4%) episodes were separated by intervals of several years. There were no statistically significant differences in demographic, seasonal, laboratory, clinical, or outcome variables between familial subsets (concurrent versus non-concurrent) or between familial and non-familial cases.
  
  
  CONCLUSIONS
  When a child is diagnosed with D+ HUS, there is an increased risk that a second family member will also develop HUS; most often within days to weeks (i.e., within a month), but in some cases episodes may be separated by intervals of years. Non-concurrent cases suggest common environmental risk factors, or perhaps a genetic predisposition. Concurrent cases suggest a common source of infection or person-to-person transmission; a genetic predisposition cannot be excluded. These observations suggest that siblings of an index case who develop diarrhea should be kept under close surveillance.
authors.affiliation: Division of Nephrology and Hypertension, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, USA. dick.siegler@hsc.utah.edu
authors.forename: R L
authors.initials: RL
authors.lastname: Siegler
authors.forename: J R
authors.initials: JR
authors.lastname: Sherbotie
authors.forename: N D
authors.initials: ND
authors.lastname: Denkers
authors.forename: A T
authors.initials: AT
authors.lastname: Pavia
mesh_terms: D000328:Adult; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D003967:Diarrhea / Q000453:epidemiology* / Q000382:microbiology*; D019453:Escherichia coli O157 / Q000302:isolation & purification / Q000378:metabolism*; D005192:Family Health; D005260:Female; D006463:Hemolytic-Uremic Syndrome / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D007223:Infant; D008297:Male; D015205:Northwestern United States / Q000453:epidemiology; D012189:Retrospective Studies; D018570:Risk Assessment; D022603:Shiga Toxins / Q000378:metabolism*; D015206:Southwestern United States / Q000453:epidemiology
chemical_list: D022603:Shiga Toxins