RT Book, Section
A1 Oberhelman, Richard A.
A2 Rudolph, Colin D.
A2 Rudolph, Abraham M.
A2 Lister, George E.
A2 First, Lewis R.
A2 Gershon, Anne A.
SR Print(0)
ID 7030958
T1 Chapter 327. Enterobiasis (Pinworm)
T2 Rudolph's Pediatrics, 22e
YR 2011
FD 2011
PB The McGraw-Hill Companies
PP New York, NY
SN 978-0-07-149723-7
LK accesspediatrics.mhmedical.com/content.aspx?aid=7030958
RD 2024/04/24
AB Enterobiasis  is  caused  by  the  pinworm  Enterobius  vermicularis,  a  strictly  human  parasite  infecting  the  gastrointestinal  tract.  Infection  occurs  worldwide,  and  clustering  of  cases  in  families  is  common.  Ingested  eggs  with  first-stage  larvae  hatch  in  the  duodenum,  and  the  larvae  develop  into  adults  in  the  cecum,  where  they  mate.  The  gravid  female  detaches  from  the  cecal  mucosa  and  migrates  down  the  large  bowel,  usually  passing  out  the  anus  onto  the  perianal  and  perineal  skin,  leaving  a  trail  of  eggs  on  the  surface  of  the  skin.  Yellow-white  female  adult  pinworms  measuring  8  to  13  mm  may  be  seen  emerging  from  the  rectum  of  infected  children,  most  often  around  10  or  11  pm.  In  approximately  5%  of  patients,  eggs  are  deposited  in  the  bowel  and  may  be  found  in  feces.  Generally,  the  worm  dies  after  ovipositing  is  completed,  so  repeated  infections  are  the  result  of  autoinfection  or  reinfection  from  other  environmental  sources.  There  is  no  good  evidence  that  retrograde  infection  occurs.1