Version July 2025
INTRODUCTION —
Young children with nephrolithiasis (kidney stones) are as likely to present with nonspecific findings such as abdominal pain, nausea, and dysuria as they are with more classic symptoms such as hematuria and flank pain. An understanding of the range of presenting symptoms for pediatric patients with kidney stones facilitates timely diagnosis and treatment of this common concern. The clinical features and diagnosis of nephrolithiasis in children and adolescents will be reviewed here. The epidemiology, risk factors, acute management, and prevention of recurrent nephrolithiasis in children are discussed separately. (See "Kidney stones in children: Epidemiology and risk factors" and "Kidney stones in children: Acute management" and "Kidney stones in children: Prevention of recurrent stones".)
CLINICAL PRESENTATION —
Presentation varies in part by patient age. Younger children are generally less able to describe localized pain or dysuria and are more likely to present with urinary tract infection (UTI) or with nonspecific symptoms.
Symptoms
Pain — Pain is the most common presenting symptom of nephrolithiasis in children; 32 to 75 percent of children with kidney stones experience pain in retrospective cohort studies [1-5]. Pain may be localized to the abdomen, back, flank (referred to as renal colic), groin, or genitals. In some cases, pain is more generalized or localized to multiple regions [1-4,6]. Older children and adolescents are more likely to identify flank pain, which waxes and wanes, as the initial concern. The chronicity of these symptoms means that nephrolithiasis should be considered as part of the clinical evaluation of pediatric patients presenting with recurrent abdominal pain [7]. Other causes of acute abdominal pain are discussed elsewhere. (See "Causes of acute abdominal pain in children and adolescents" and "Emergency evaluation of the child with acute abdominal pain" and "Back pain in children and adolescents: Evaluation", section on 'Causes of back pain in children'.)
Hematuria — In a case series of pediatric patients with nephrolithiasis, hematuria was the presenting symptom in 30 to 55 percent [1-4]. In patients with nephrolithiasis, urine is typically red, in contrast to the brown or cola-colored urine seen in glomerulonephritis. Other causes of hematuria are discussed elsewhere. (See "Evaluation of gross hematuria in children".)
Dysuria and urgency — Between 10 and 36 percent of children with nephrolithiasis present with symptoms of dysuria and urgency suggestive of a UTI. In one retrospective cohort study of children with nephrolithiasis, 30 percent were diagnosed with a stone-associated UTI during a minimum of two years of follow-up [4-6,8,9]. (See "Etiology and evaluation of dysuria in children and adolescents".)
In some cases, these symptoms are attributable to the presence of a stone in the bladder or urethra without an associated infection. In other cases, dysuria and/or urgency are the result of a UTI. In one retrospective cohort, between 30 and 36 percent of children with kidney stones had a UTI on presentation [10]. UTI may contribute to stone formation as a result of urinary stasis, especially in young children who have underlying kidney anomalies (eg, ureteropelvic junction obstruction) [1,2,6]. (See "Congenital ureteropelvic junction obstruction", section on 'Symptomatic patients'.)
Conversely, kidney stones may cause infection. Children who are predisposed to form kidney stones are at higher risk of ureteral obstruction, which can result in upper tract UTI [9]. UTI in a patient with partially or completely obstructing ureteral stones is an indication for urgent surgical decompression. Therefore, we counsel patients with a history of kidney stones to seek medical care immediately upon development of symptoms/signs of UTI (eg, fever, chills, and/or dysuria). (See "Kidney stones in children: Acute management", section on 'Indications'.)
An evaluation for UTI is part of the standard laboratory assessment for patients with suspected nephrolithiasis. (See 'Laboratory evaluation' below and "Urinary tract infections in infants older than one month and children younger than two years: Clinical features and diagnosis".)
Nausea and vomiting — Gastrointestinal symptoms such as nausea and vomiting are common, occurring in up to 56 percent of pediatric patients at diagnosis with nephrolithiasis [1,11]. (See "Approach to the infant or child with nausea and vomiting".)
Asymptomatic presentation in young children — In retrospective cohort studies, most children experienced symptoms at diagnosis with nephrolithiasis, though 15 to 43 percent were asymptomatic. Asymptomatic patients were diagnosed with nephrolithiasis when abdominal imaging was performed for other purposes, such as screening for those a family history of kidney stones [1-3,10]. Younger children (<6 years of age) are the most likely group to be diagnosed with nephrolithiasis in the absence of symptoms. This is because they are more likely than older children to develop nonureteral stones, which do not cause painful ureteral obstruction. In one retrospective cohort, 32 percent of children under five years of age developed ureteral stones, compared with 64 percent of school-aged children and 82 percent of adolescents [12]. In addition, young children may be unable to describe the location and severity of pain accurately [13].
INITIAL EVALUATION
History — The evaluation begins with a history that identifies any of the following factors that are associated with an increased likelihood for nephrolithiasis:
●History of previous kidney stone.
●Family history of nephrolithiasis. In one case series, 16 percent of children had a first-degree relative and 17 percent had a second-degree relative with kidney stones [3]. Information about specific family members with a history of stone formation can suggest an inheritance pattern for single-gene (monogenic) causes of nephrolithiasis (eg, X-linked, dominant) [14]. (See "Kidney stones in children: Epidemiology and risk factors".)
●History of underlying kidney and urinary tract structural abnormalities. (See "Kidney stones in children: Epidemiology and risk factors", section on 'Congenital/structural abnormalities'.)
●History of known genetic disorders associated with kidney stones or underlying metabolic conditions associated with nephrolithiasis, such as Lesch-Nyhan syndrome or malabsorptive conditions that increase enteric absorption of oxalate and hyperoxaluria. Additionally, dietary history may identify risk factors such as the use of a ketogenic diet to treat epilepsy, which is a risk factor for calcium phosphate stones due to hypocitraturia and hypercalciuria. (See "Kidney stones in children: Epidemiology and risk factors".)
●History of medications associated with stone formation (eg, furosemide, topiramate, zonisamide, acetazolamide, sulfadiazine, allopurinol, high-dose vitamin D or C, ceftriaxone sodium and indinavir sulfate [15,16]) or a history of conditions associated with such medications (eg, tumor lysis syndrome) [17]. (See "Kidney stones in children: Epidemiology and risk factors", section on 'Other metabolic causes'.)
●History of recurrent urinary tract infection (UTI), especially with a urease-producing organism such as Proteus or Klebsiella. (See "Kidney stones in children: Epidemiology and risk factors", section on 'Infection'.)
Physical examination — The physical examination in the child with suspected nephrolithiasis should include:
●Vital signs, including temperature. The presence of fever may represent a UTI, which warrants immediate attention; tachycardia and hypotension may indicate disseminated infection or sepsis. (See "Kidney stones in children: Acute management", section on 'Management of urinary tract infection' and "Urinary tract infections in infants older than one month and children younger than two years: Clinical features and diagnosis" and "Urinary tract infections in infants older than one month and children younger than two years: Clinical features and diagnosis", section on 'Clinical presentation'.)
●An abdominal examination to localize pain and/or identify signs of urinary obstruction (eg, palpable bladder).
●Measurement (and review of growth charts). Poor weight gain and/or poor growth may be an indication of a congenital or chronic condition that may be associated with nephrolithiasis, such as renal tubular acidosis or Dent disease. (See "Kidney stones in children: Epidemiology and risk factors".)
●Blood pressure measurement and assessment for edema. The presence of hypertension (particularly persisting beyond the period of acute presentation) and/or edema in a child with hematuria suggests glomerular disease. (See "Glomerular disease: Evaluation in children".)
Laboratory evaluation — The initial laboratory evaluation for the child with suspected nephrolithiasis includes:
●Urinalysis – Urinalysis (UA) in patients with kidney stones is often associated with hematuria (microscopic or macroscopic) without elevated white blood cells [18]. However, the absence of hematuria does not rule out a kidney stone. In some cases, UA may suggest a co-occurring UTI (eg, positive leukocyte esterase, nitrites, and elevated white blood cells) [18]. Findings on UA are discussed elsewhere. (See "Evaluation of gross hematuria in children" and "Evaluation of microscopic hematuria in children" and "Urinalysis in the diagnosis of kidney disease".)
Examination of the urine sediment should be performed where possible. Although the presence of crystals on the urine sediment does not establish the diagnosis of nephrolithiasis, it suggests diagnoses that predispose towards stone formation. As an example, cystine crystals (which are colorless, flat, and hexagonal) are diagnostic of cystinuria (picture 1). Other crystals that can be seen in the sediment include calcium oxalate (picture 2A-B), calcium phosphate, uric acid (picture 3A-B), and phosphate (picture 4). Drugs, such as sulfadiazine, can also crystallize in the urine (picture 5).
Additional evaluation for causes of recurrent kidney stones is discussed elsewhere. (See "Kidney stones in children: Prevention of recurrent stones", section on 'Evaluation for underlying risk factors'.)
●Urine culture – A urine culture should be obtained if symptoms of UTI (eg, dysuria, frequency) or nonspecific symptoms of infection (eg, fever, chills, nausea/vomiting) are present and/or if UA is suggestive of UTI. The diagnosis of UTI is discussed elsewhere. (See "Urinary tract infections in infants older than one month and children younger than two years: Clinical features and diagnosis".)
●Other tests
•Serum creatinine and/or cystatin C – Serum creatinine and/or cystatin C are indications of kidney function. We obtain these tests when there is clinical concern for an obstructing stone or in patients with solitary kidney or known impairments in kidney function. (See "Kidney stones in children: Acute management", section on 'Indications'.)
•Pregnancy test – In patients who can become pregnant, a pregnancy test (detection of human chorionic gonadotropin in urine or blood) will often be a part of the clinical evaluation for those presenting with abdominal pain and/or genitourinary tract bleeding. (See "Clinical manifestations and diagnosis of early pregnancy", section on 'When to be concerned about early pregnancy symptoms'.)
Additional laboratory testing will be based on clinical presentation.
DIAGNOSIS
When to suspect nephrolithiasis — The diagnosis of nephrolithiasis should be suspected in pediatric patients with acute onset of abdominal, lower back, or flank pain and/or urinary symptoms such as hematuria, dysuria, and/or urgency. In particular, a history of prior kidney stones in the patient or first-degree relatives is highly suggestive of nephrolithiasis as the cause of symptoms. Nausea and vomiting are common in patients with nephrolithiasis but may accompany other causes of abdominal pain, such as gastroenteritis. (See 'Differential diagnosis' below.)
A prompt and thorough evaluation can correctly determine the diagnosis and prevent obstruction in patients with nephrolithiasis.
How to confirm the diagnosis — Irrespective of symptoms, the diagnosis of nephrolithiasis is confirmed by the detection of a stone on imaging studies (usually ultrasound [US], occasionally noncontrast computed tomography [CT]) or by retrieval of a passed stone.
We instruct patients to urinate into a strainer when possible to catch any passed stones. If passed, stones should be saved for additional analysis [16]. (See "Kidney stones in adults: Evaluation of the patient with established stone disease", section on 'Stone analysis'.)
Ultrasound — In most patients who have suspected nephrolithiasis, we perform a kidney US. If a stone has not been passed, US can effectively detect stones in the kidney without exposing patients to radiation [19,20]. Among patients who have passed a stone, we generally perform a US soon after the nephrolithiasis diagnosis is made. In these patients, US is used to identify other stones and/or identify underlying anomalies of the kidney or urinary tract. (See "Evaluation of congenital anomalies of the kidney and urinary tract (CAKUT)".)
Ultrasonography can detect radiolucent stones, such as uric acid stones, and urinary obstruction (image 1 and image 2) [21]. However, it is limited in its ability to uncover small stones (eg, less than 5 mm), papillary or calyceal stones, or ureteral stones [20,22].
The experience and expertise of the ultrasonographer are important factors in the sensitivity of the study, especially in the accurate detection of small stones or ureteral stones.
Additional evaluation in selected patients — In patients with suspected nephrolithiasis who have not passed a stone and in whom a US does not identify a stone, we use noncontrast helical CT, provided that radiation is not contraindicated (eg, pregnant patients). We do not routinely use plain abdominal radiograph, though it may be used in resource-limited environments in which US and/or CT are not available.
●Noncontrast CT – We do not use CT for initial imaging in most pediatric patients with suspected nephrolithiasis. While CT is a more sensitive modality than US for the detection of kidney stones, it exposes children to ionizing radiation (image 3A-B) [11,19,23-26].
CT can detect stones in the following conditions:
•Ureteral stones, which may not be detected by ultrasonography
•Small (ie, 1 mm in diameter) stones, which are not detected by ultrasonography or plain radiography
Contrast is not used in CT protocols for suspected nephrolithiasis, as it may obscure stones.
Radiation exposure from CT is a significant concern for pediatric patients. Many pediatric institutions have low-dose radiation protocols for CT scans performed to evaluate for kidney stones in children and adolescents [19]. Such size-adjusted protocols should be implemented whenever possible for CT scans in pediatric patients, who are at higher risk than adults of radiation-related malignancy [27-30]. (See "Radiation-related risks of imaging", section on 'Children and adolescents'.)
●Abdominal plain radiography – In settings where kidney ultrasonography and CT are not available for children, plain abdominal radiography remains a reasonable alternative, recognizing that the reported sensitivity of this study is approximately 60 percent [23]. A plain abdominal radiograph will detect radiopaque stones (eg, calcium, struvite, and cystine stones) (image 4) but will miss radiolucent stones (eg, uric acid stones), may miss small stones or those that overlay bony structures, and will not detect urinary obstruction. It may be challenging to distinguish between kidney stones and fecaliths in the overlying bowel on plain radiography.
POSTDIAGNOSIS EVALUATION —
Further evaluation for metabolic risk factors (ie, hypercalciuria and hyperuricosuria) is performed once the acute episode is over and the patient is at home, fully ambulatory, consuming a regular diet, and free of infection [31,32]. (See "Kidney stones in children: Prevention of recurrent stones".)
DIFFERENTIAL DIAGNOSIS —
Kidney stones are differentiated from other causes of pain, hematuria, dysuria, fever, and gastrointestinal symptoms by history, physical examination, and imaging. (See 'Initial evaluation' above.)
●Urinary tract infection (UTI) – UTI can present concurrently with kidney stones. In contrast to patients with nephrolithiasis, children with isolated UTI usually begin to show clinical improvement within 24 to 48 hours of initiation of appropriate antibiotic therapy. Therefore, if a patient's clinical condition worsens or fails to improve as expected within 24 to 48 hours of the start of antimicrobial therapy, imaging should be performed to determine if a stone is present. (See "Urinary tract infections in infants older than one month and children younger than two years: Clinical features and diagnosis" and "Acute simple cystitis in female adults".)
In a large retrospective cohort of pediatric patients with kidney stones, risk of developing UTI in association with nephrolithiasis was associated with age under two years and metabolic abnormality of the urine (eg, hypercalciuria, hypocitraturia, hyperoxaluria) [9]. (See "Nephrocalcinosis in neonates".)
●Other causes of acute abdominal, flank, or back pain – Acute onset of abdominal, flank, or back pain may be associated with other pathologic processes requiring urgent intervention. History and examination can provide vital diagnostic information. For example, gastroenteritis usually presents with nausea, vomiting, and abdominal pain (symptoms that are common in nephrolithiasis). However, the presence of fever and diarrhea are associated with gastroenteritis but are less common in nephrolithiasis.
In young children in particular, localizing pain may be challenging, and prompt abdominal imaging is often required. The specific imaging modality (ultrasound [US], CT scan, or other) will depend on presentation and clinical setting. We review some diagnoses that present similarly to nephrolithiasis in young children here, though there are many others. The causes and approach to evaluation of acute abdominal pain and back pain in pediatric patients are discussed elsewhere. (See "Causes of acute abdominal pain in children and adolescents" and "Emergency evaluation of the child with acute abdominal pain" and "Back pain in children and adolescents: Causes".)
•Ovarian pathology – Ovarian torsion, cyst, mass, or abscess may also be associated with intermittent pain prior to the episode of acute pain. Acute pelvic pain is particularly suggestive of ovarian involvement. Noninfectious processes will not usually be associated with dysuria, and hematuria is not associated with any of these diagnoses. Vaginal bleeding may be present and can lead to the presence of red blood cells on urinalysis (UA). (See "Ovarian and fallopian tube torsion", section on 'Diagnosis'.)
•Intussusception – Intussusception presents with acute onset of abdominal pain, most often in children <2 years of age. Pain may be intermittent, and vomiting and nausea are common. Bloody stools and abdominal mass may be present in some patients with intussusception, but at least one-third do not present with either sign [33]. Imaging is usually required to distinguish between these diagnoses. (See "Intussusception in children", section on 'Evaluation'.)
•Appendicitis – Appendicitis may be distinguished from nephrolithiasis by the early localization of pain to the periumbilical region, peritoneal irritation, and, eventually, signs of localization of pain to the lower right quadrant. It is not usually associated with dysuria or hematuria. (See "Acute appendicitis in children: Clinical manifestations and diagnosis", section on 'Clinical manifestations'.)
●Other causes of gross hematuria – Acute onset of gross hematuria may be associated with other pathologic processes requiring urgent intervention. In children, the most common causes of gross hematuria include UTI, irritation of the meatus or perineum, and trauma. These are differentiated from nephrolithiasis by the history and physical examination. Glomerular disease, such as postinfectious glomerulonephritis, is a less common cause of gross hematuria; it is distinguished from nephrolithiasis by cola-colored urine instead of red urine, examination of the urinary sediment, and (in some patients) the presence of hypertension and/or edema. (See "Evaluation of gross hematuria in children" and "Glomerular disease: Evaluation in children".)
SOCIETY GUIDELINE LINKS —
Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Kidney stones" and "Society guideline links: Pediatric nephrolithiasis".)
INFORMATION FOR PATIENTS —
UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient education: Kidney stones in children (The Basics)")
●Beyond the Basics topics (see "Patient education: Kidney stones in children (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Clinical presentation – Childhood nephrolithiasis usually presents with symptoms, most commonly abdominal, back, or flank pain; nausea/vomiting; and/or gross hematuria. However, 15 to 20 percent of children are asymptomatic and are diagnosed because of stone detection when abdominal imaging is performed for other purposes. Urinary tract infection (UTI) and asymptomatic presentation are more common in children below six years of age. (See 'Clinical presentation' above.)
●Initial evaluation – The initial evaluation of a child with suspected nephrolithiasis includes the following:
•History – History focusing on underlying risk factors for stone formation (eg, family history, kidney and urinary tract structural abnormalities, metabolic disorders, or recurrent UTI). (See "Kidney stones in children: Epidemiology and risk factors".)
•Physical examination – Physical examination that includes measurement of blood pressure and growth parameters as well as abdominal examination for signs of urinary obstruction or another cause of abdominal pain. (See 'Physical examination' above.)
•Laboratory tests – Laboratory tests including urinalysis (UA) and examination of urine sediment (or of a passed stone) can identify metabolic diseases that predispose patients to kidney stones (eg, cystinuria). Urine culture is used to identify causative organisms and guide treatment in cases of UTI. We evaluate kidney function in patients with obstructing stones, a solitary kidney, or suspected medical kidney disease. (See 'Laboratory evaluation' above and "Kidney stones in children: Epidemiology and risk factors", section on 'Cystinuria'.)
●Diagnosis – The diagnosis of nephrolithiasis should be suspected in pediatric patients with acute onset of abdominal, lower back, or flank pain and/or urinary symptoms such as hematuria, dysuria, and/or urgency. Diagnosis of nephrolithiasis is confirmed based on identifying a kidney stone on imaging or visualizing a passed stone. (See 'Diagnosis' above.)
•Ultrasound as initial imaging – In children with suspected nephrolithiasis, we obtain an ultrasound (US) as initial imaging given that US does not expose children to radiation and has relatively good sensitivity for radiolucent stones and urinary obstruction. In children who have passed a stone, we generally perform a US soon after the nephrolithiasis diagnosis is made to evaluate for other stones and/or congenital abnormalities of the kidney and urinary tract. (See 'Ultrasound' above.)
•Noncontrast computed tomography, in select cases – If no stone is identified on US and the patient has not passed a stone, we obtain noncontrast CT using a low-radiation stone protocol in patients who are not pregnant. CT may detect small stones that are not visible on US. (See 'Additional evaluation in selected patients' above.)
•Differential diagnosis – The differential diagnosis for nephrolithiasis in pediatric patients depends on symptoms at presentation. Other causes of abdominal pain and nausea in pediatric patients include gastroenteritis, ovarian pathology, intussusception, appendicitis, and UTI. Other causes of hematuria include UTI, trauma, and glomerulonephritis. (See 'Differential diagnosis' above.)
