This is a 10-year old male presenting to the E.D. 
with a history of abdominal pain for two days.  He 
describes the pain mostly in his periumbilical region.  
The pain is clearly worse today.  He has no vomiting or 
diarrhea.  His appetite is poor and he is not able to 
ambulate well due to pain.  There is no history of fever.  
There is no history of coughing, chest pain, or dysuria.  
His past history is significant for asthma.
     Exam:  VS T37.4 (tympanic), P92, R16, BP 120/62.  
He is alert, not toxic, resting comfortably.  His hydration 
is good.  Heart regular without murmurs.  Lungs clear.  
Abdomen is flat and generally soft.  There is mild 
guarding and tenderness mostly over the periumbilical 
region.  Bowel sounds are absent.  No hernias are 
evident.  Observing his gait, he ambulates slowly in a 
bent forward position.  He refuses to jump.  Asking him 
to cough results in moderately severe abdominal pain.  
A rectal exam does not yield any localizing signs.
     Laboratory studies:  CBC  WBC 14,500, 81% segs, 
2% bands, 8% lymphs, 6% monos, 3% atypical lymphs, 
Hgb. 14.3, Hct. 43.0, platelet count 344,000.  Urinalysis 
SG 1.030, trace protein, otherwise negative.
     An abdominal series is obtained.

View abdominal series:  Flat (supine) view.


View upright view.

     Given the patient's clinical findings, consider the 
differential diagnosis at this point and what we should 
be most interested in, in examining these radiographs.  
For example, an obstruction is not likely given the 
absence of previous abdominal surgery, the absence of 
vomiting, the flat abdominal contour, and no clinical 
evidence of an incarcerated hernia.  Appendicitis is a 
consideration given the peritoneal signs exhibited, the 
patient's gait suggesting peritonitis, his anorexia, and 
modest leukocytosis.  His pain and tenderness are not 
in the right lower quadrant.  However, the absence of 
this cannot reliably exclude appendicitis. 
     These films are dark; making the lateral edges of the 
abdomen difficult to view.  The gas distribution shows 
gas and feces throughout the colon.  However, the 
ascending colon is displaced medially.  It appears to be 
separated from the right flank, raising the possibility of a 
mass lateral to the colon.  There is no bowel dilation 
and no air fluid levels.  No fecolith is seen.  No free air 
is evident.  
     An abdominal ultrasound is performed.  There is 
evidence of a fluid and gas-containing structure 
adjacent to the umbilicus consistent with an ectopic 
appendicitis or a Meckel's diverticulitis.
     An exploratory laparotomy is performed.  An acutely 
inflamed Meckel's diverticulum is noted.  This is 
resected.  His appendix is normal.  He is placed on 
antibiotics post-operatively, and he recovers 
uneventfully.
     The radiographic findings of appendicitis are highly 
variable.  This is discussed in some detail in Case 19 of 
Volume 3, Abdominal Pain and the Peritoneal Fat 
Margins.  This case specifically discusses the 
significance of the peritoneal fat margins.  Usually, the 
bowel is close to the peritoneal fat margins bilaterally, 
but in this current case, the bowel is displaced far from 
the right peritoneal fat margin displaying a mass effect.  
These radiographs were too dark for the scanner to 
pick-up the peritoneal fat margins on the image 
displayed here.  However, since this case is extreme, it 
is evident that the ascending colon is being displaced 
medially.  Often this displacement of the bowel away 
from the peritoneal fat margin can be subtle.  Although 
this patient's diagnosis is an unusual one, the general 
principles of identifying a patient requiring prompt 
abdominal surgery still apply.