A pediatrician saw two patients with urolithiasis over two weeks that had been managed differently and she wondered what were the factors that had been used for their treatment decisions. The first was a 17-year-old female who was traveling by car and had exquisite abdominal and flank pain that became worse and caused the family to seek care at the nearest hospital along the road. The diagnosis was made by computed tomographic scan and the patient was taken to the operating room for removal of the stone “just above my bladder” and placement of a stent. Her medical records showed that it was a 7 mm calcium oxalate stone causing mild hydronephrosis just above the ureterovesical junction. The stent was removed 10 days later and she had been doing well since. The second patient was an 8-year-old male who had sudden onset of abdominal and flank pain and was seen in the local emergency room. A 3 mm stone located above the ureterovesical junction that was not causing hydronephrosis was diagnosed by computer tomography. The patient responded to IV fluids and pain management in the emergency room and was discharged home. The pain resolved within 48 hours but the stone was not collected. Both patients underwent further metabolic evaluations for causes of the urolithiasis formation.
Although pediatric uroliathiasis is relatively rare, there has been an increasing number of children evaluated for renal stones over time. For an overview of uroliathiasis click here.
Renal colic classically has paroxysmal pain that is severe, radiates toward the groin and the patient is not able to find a comfortable position. They may also have irritability, nausea, emesis, increased urinary frequency, dysuria and hematuria. 85-90% of patients will have macro- or microscopic hematuria but up to 15% of patients with urolithiasis will not have hematuria.
Clinical differential diagnosis includes but is not limited to:
- Ovarian torsion
- Urinary tract infection
The most common locations for stones to lodge are the ureteropelvic junction, the ureterovesical junction and where the ureter crosses the common iliac vessels.
Size and location of the stone and if it is causing urinary obstruction guide treatment decisions. Stones that are smaller than 4 mm and that are non-obstructing are usually managed conservatively. Those that are larger than 4 mm or causing obstruction usually require interventional management. Stones that are higher up in the urinary tract are more likely to require intervention. If initially treated conservatively and after 3-6 weeks the patient’s stone has not resolved then interventional treatment is usually indicated.
Conservative management includes aggressive hydration, pain management and nausea/emesis management. In the emergency room IV hydration at 1.5-2.0 times maintenance, pain management with narcotics and non-steroidal antiinflammatory medication (i.e. morphine and ketoralac) and management of nausea and emesis by IV medication are the standards of care. If the patient improves then they may be discharged to continue aggressive oral hydration and pain management.
Interventional management includes extracorporeal shockwave lithotripsy which is good for a variety of stones and locations but is limited in lower kidney pole locations, with staghorn stones or patients with abnormal urinary system anatomy. Percutaneous nephrolithotomy is good for large lower kidney pole stones or staghorn stones. Endoscopy is good for distal ureteral stones and especially if less than 15 mm in size. Ureteral stents may be placed until post-operative edema resolves (generally 1-2 weeks)
Recurrence rate of calculi is 24-33%.
Questions for Further Discussion
1. What are the most common types of kidney stones?
2. What metabolic evaluations should be considered for patients with kidney stones?
To Learn More
To view pediatric review articles on this topic from the past year check PubMed.
Evidence-based medicine information on this topic can be found at the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.
Information prescriptions for patients can be found at MedlinePlus for this topic: Kidney Stone.
To view current news articles on this topic check Google News.
To view images related to this topic check Google Images.
To view videos related to this topic check YouTube Videos.
Wu HY, Docimo SG. Surgical management of children with urolithiasis. Urol Clin North Am. 2004 Aug;31(3):589-94, xi.
Cameron MA, Sakhaee K, Moe OW. Nephrolithiasis in children. Pediatr Nephrol. 2005 Nov;20(11):1587-92.
Schissel BL, Johnson BK. Renal stones: evolving epidemiology and management. Pediatr Emerg Care. 2011 Jul;27(7):676-81.
Granberg CF, Baker LA. Urolithiasis in children: surgical approach. Pediatr Clin North Am. 2012 Aug;59(4):897-908.
ACGME Competencies Highlighted by Case
2. Essential and accurate information about the patients’ is gathered.
3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
4. Patient management plans are developed and carried out.
7. All medical and invasive procedures considered essential for the area of practice are competently performed.
8. Health care services aimed at preventing health problems or maintaining health are provided.
13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.
14. Knowledge of study designs and statistical methods to appraisal clinical studies and other information on diagnostic and therapeutic effectiveness is applied.
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa Children’s Hospital