A Large Calcified Kidney Stone
Radiology Cases in Pediatric Emergency Medicine
Volume 7, Case 6
Loren G. Yamamoto, MD, MPH
Kapiolani Medical Center For Women And Children
University of Hawaii John A. Burns School of Medicine
     This is a 14 year old female who presents to the 
emergency department with severe pain in her lower 
back for the past two hours.  She describes the pain as 
sharp and worse than being stabbed by a knife.  She 
has also had some abdominal pain along with 
menstrual cramps for the past two days.  She took 
some acetaminophen before coming to the ED and she 
states that the pain is slightly better.  There is no 
history of fever or chills.  There is some suggestion of 
urgency, but no dysuria.  She feels nauseated and she 
has vomited twice.  Her LMP was four weeks ago and 
she denies any possibility of pregnancy.
     Her past medical history is unremarkable.  There is 
no family history of kidney stones.
     Exam:  VS T36.7 (oral), P89, R 20, BP 90/60, 
oxygen saturation in room air 99%.  She is alert and 
cooperative.  She is uncomfortable, but she does not 
appear to be in severe pain.  HEENT unremarkable.  
Neck supple.  Heart regular without murmur.  Lungs 
clear.  No chest tenderness.  Her abdomen is soft and 
non-tender on palpation.  Bowel sounds are 
normoactive.  There is no rebound tenderness.  Her 
back is very tender over her mid lumbar spine and this 
is somewhat worse over her right flank.  Her distal 
pulse are good.  She is able to move all her extremities 
well and she speaks well.
     A urine dipstick is positive for blood.  Blood studies 
are drawn and an IV is started.  She is given morphine 
for pain.  Her urine pregnancy test is negative and she 
is sent to radiology for an abdominal series.

View abdominal series.
Supine view (below)

Upright view (below)

     Any abnormalities here?  What diagnostic 
procedure would you order next?

     There is a calcified density in the right lower 
quadrant visible on both views of the abdominal series.  
This is suspected to be a ureteral stone since her 
symptoms are consistent with this.  

View a close-up of this stone.

     She is given additional doses of morphine to control 
her pain.  Her laboratory studies show a normal CBC 
(WBC 6,700) and chemistry (normal BUN, creatinine, 
SGPT and lipase).  Her urinalysis shows 5-10 WBCs 
and 50-100 RBCs.
     An abdominal ultrasound is performed but she is too 
uncomfortable to cooperate well and this study is 
non-diagnostic except for the presence of mild 
hydronephrosis of her right kidney.
     An intravenous pyelogram (IVP) is ordered.  A 20 
minute and a delayed abdominal flat plate are shown 

View 20-minute IVP flat plate (below).

View delayed IVP (below).

     An earlier IVP flat plate demonstrates prompt 
excretion of contrast from the left kidney.  The 
20-minute IVP shows contrast excretion from the left 
kidney and a contrast enhanced right kidney without 
contrast excretion.  The delayed IVP (a slightly oblique 
view) shows delayed contrast excretion from the right 
kidney confirming an obstruction on the right.

     Is the calcified density in the right lower quadrant 
causing the obstruction?

     The IVP demonstrates an obstruction in the right 
ureter, along with a clinical presentation consistent with 
ureteral colic.  This makes it very likely that she has a 
ureteral stone.  However, the calcified density is very 
large for a ureteral stone.  Additionally, the location of 
the calcified density is not exactly in the expected path 
of the ureter.  An appendicolith is suspected.
     Her pain has subsided following the administration 
of analgesics.  Interestingly, she did not have much 
abdominal pain on initial presentation, since she was 
mostly complaining of back pain.  Now that her back 
pain is under better control, she is complaining of some 
abdominal pain, but it is not severe.  The severity of her 
nausea has been fluctuating.  She is given some 
promethazine and her nausea has now subsided.
     A urologist is consulted for her ureteral obstruction 
and a pediatric surgeon is consulted for the possibility 
of appendicitis.  An abdominal CT scan is ordered; 
however, the radiologist is reluctant to give her a 
second dose of IV contrast for the CT scan.  She is 
followed clinically and she passes a small amount of 
tissue in her urine which contains a tiny stone.  Her 
abdominal pain persists and she eventually undergoes 
an appendectomy which shows an early appendicitis 
with an appendicolith.

     This is an interesting case in that the patient 
actually has two different acute conditions 
simultaneously.  Although the calcified density on her 
abdominal series appeared to be too large for a 
ureteral stone, this was assumed to be a large ureteral 
stone because of her clinical presentation.  In fact, the 
stone was felt to be too large to pass spontaneously, so 
the possibility of lithotripsy or surgical retrieval of the 
stone were discussed.   Calcifications in the right lower 
quadrant should always raise the possibility of an 
appendicolith and acute appendicitis.  As a pitfall, 
clinicians may attribute this finding to other causes 
such as vascular calcification, gynecological 
calcification, intestinal contents (ingested sand or 
gravel), or as in this case, a ureteral stone.  A CT scan 
without and then with contrast may have been a more 
optimal study which would have identified the ureteral 
stone and the appendicolith.

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Web Page Author:
Loren Yamamoto, MD, MPH
Professor of Pediatrics
University of Hawaii John A. Burns School of Medicine