Hematuria/Dysuria May Be Inconstant in Children With Recurrent Abdominal Pain/Urolithiasis
By Laurie Barclay, MD
Medscape Medical News
November 13, 2009 — Hematuria and dysuria may not always be present in children with recurrent abdominal pain (RAP) and urolithiasis, according to the results of an observational study reported online in the November 9 issue of Pediatrics.
"Identification of the clinical hallmarks of urinary tract involvement is crucial in selecting those children with RAP who require focused evaluation of the urinary tract," write Cesare Polito, MD, from Second University of Naples in Naples, Italy, and colleagues. "The location of pain in the flank as well as hematuria and dysuria are considered the only warning signs indicating more in-depth investigation of urinary tract involvement in children with RAP. To date, no study has addressed the frequency of pain attacks in children with urolithiasis."
The objective of this study was to describe the clinical presentation and features of pain attacks in 100 consecutive pediatric patients with RAP and urolithiasis. Rate of previous appendectomy in these cases was compared vs that in 270 control subjects, and frequency of pain attacks in these cases was compared vs that reported by children with functional or organic gastrointestinal RAP.
When first seen, 53 patients had no history of dysuria or gross hematuria; only 35 had hematuria; and 41 patients underwent workup for urolithiasis only because of a family history of kidney stones associated with RAP. History of previous hospitalization for abdominal symptoms was present in 29 patients. Appendectomy had previously been performed in 16 patients and in 4 control subjects (1.5%; P < .0001).
Abdominal ultrasonography was performed in 37 patients 2 to 28 months before the diagnosis of urolithiasis, and results were negative for urinary calculi. Among patients younger than 8 years, abdominal pain was central or diffuse in location in 69%. In patients with RAP and urolithiasis, the mean frequency of pain attacks was 4 to 9 times lower vs patients with functional or organic gastrointestinal RAP.
"Because of the inconstant occurrence of dysuria and hematuria, the location of pain in areas other than the flank, and the lack of calculi shown on imaging studies performed after pain attacks, the urologic origin of pain may be overlooked and ineffective procedures performed," the study authors write. "The possibility of urolithiasis should be considered in children with RAP who have a family history of urolithiasis and/or infrequent pain attacks, even when dysuria and hematuria are lacking, and in younger children even when pain is not lateral."
Limitations of this study include observational design and relatively small sample size.
"It seems advisable to perform at least 2 renal ultrasound examinations 1 to 2 years apart and 3 nonconsecutive complete evaluations of urinary solute excretion abnormalities in outpatient children with RAP and a family history of urolithiasis, even in the absence of specific urinary signs and symptoms, and in younger patients, although the pain may be central or diffuse in the whole abdomen," the study authors conclude. "Computed tomography may be particularly useful in the emergency department after a nondiagnostic ultrasound scan. Restricting these investigations to patients with infrequent painful episodes (4 days/month or less) will help improve the cost/benefit ratio of this approach."
The study authors have disclosed no relevant financial relationships.
