Symptoms of urolithiasis

Kidney stones may be asymptomatic and detected as an incidental finding on an X-ray or during an ultrasound examination of the kidneys, which is often done for other reasons. They may also present with a dull flank ache at the back. The classic symptom of kidney stones is intermittent, excruciating pain. It begins in the lumbar region at the back, then spreads forward and downward to the abdomen, groin, genitals, and medial thigh. Vomiting, nausea, increased sweating, and general weakness are also possible. Intense pain may last for several hours, followed by a dull flank ache. The patient with renal colic appears seriously ill and restless, turning from side to side in an attempt to relieve the pain. A common symptom of renal colic is hematuria of varying severity up to the development of macrohematuria. Fever and chills are sometimes noted. An objective examination reveals tenderness and reflex tension in the corresponding lumbar region. Deep palpation increases the patient's discomfort, but there is no pain when the pressure is suddenly released. A urinary tract infection is possible. Urinary tract obstruction, if present, is usually unilateral. However, in young children, the typical classic picture of renal colic is rare; fever, signs of intoxication, anxiety, and vomiting are usually noted. In this case, the diagnosis can only be made after a comprehensive examination of the child.

In children, bladder stones are clinically manifested by abdominal pain, dysuric phenomena (urinary retention, frequent and painful urination). In 10% of children, stones and sand pass spontaneously. Bladder stones are most often phosphate or mixed, yellowish-white in color, usually large in size, often tightly fixed to the bladder mucosa (ligature). In most cases, bacteriuria and intermittent leukocyturia are detected. When analyzing pedigrees in families of children with bladder stones, hereditary predisposition to kidney diseases was not revealed.

The most severe course of urolithiasis is observed in children with coral stones and multiple recurrent stone formation in the kidneys. Boys predominate in these groups (4:1). Almost all children have stones detected in preschool age with a persistently progressive increase in the size of the stone or the number of recurrent stones in the kidney. Coral stone formation is most often asymptomatic and is detected by chance with a sharp decrease in the function of the affected kidney. All children with coral stones are characterized by a persistent torpid course and ineffective therapy for pyelonephritis. Often, such children have chronic renal failure with a decrease in glomerular filtration by 20-40%. In some children, X-ray examination reveals abnormalities in the structure of the kidneys. According to pedigree data, in 40% of cases, a hereditary predisposition to urolithiasis is noted on the mother's side.

In children with single kidney and ureter stones, calculi of various locations and densities are easily determined radiologically. Concrements often cause renal dysfunction, expansion and deformation of the renal pelvis. In children with single kidney stones, spontaneous passage of calculi is often noted. Due to the elasticity and lower rigidity of the urinary tract tissues, the peculiarities of symptoms in children are considered to be a lower frequency and severity of intractable renal colic and a relatively more frequent passage of small stones and sand. Concrements in children are more often phosphate or oxalate-calcium.

Peculiarities of urolithiasis in children

In recent years, there has been an increase in the detection of urolithiasis worldwide and in all age groups. Moreover, all researchers emphasize two circumstances: detection is obviously significantly lower than the actual prevalence; rather late manifestations of urolithiasis or its complications are detected - the passage of stones, renal colic, expansion of the renal cavity systems, calculous pyelonephritis. On average, in Europe, among both adults and children, urolithiasis occurs with a frequency of 1 to 5%.

Stone formation in children of different age groups differs both in the causes of stone formation and in clinical manifestations, which complicates the diagnosis of urolithiasis. The younger the child, the greater the role of urinary tract infection among the causes of stone formation. In children under 2 years of age, infection is considered the cause of stone formation. Among infectious agents, the main role is given to Proteus and Klebsiella - microorganisms capable of decomposing urine urea with the formation of urate and phosphate stones. Obviously, therefore, in terms of the composition of stones in children under 5 years of age, phosphate-calcium lithiasis predominates. Moreover, phosphate-calcium stones in children under 5 years of age can also be coral-shaped.

Classic symptoms of urolithiasis are renal colic, pain, dysuria, hematuria and pyuria. The listed signs are considered relative. An absolute sign is the passage of stones and sand. According to O. L. Tiktinsky, renal colic in adults is a symptom of urolithiasis in an average of 70%, and when stones are localized in the ureter - up to 90%. However, the younger the child, the less often typical renal colic occurs with urolithiasis. Among the children with urolithiasis that we observed, typical renal colic occurred in 45%. Renal colic in both children and adults may not be accompanied by immediate passage of stones. The first passage of a stone may occur several weeks or months after the colic has been relieved.

One of the most common reasons for examination with subsequent detection of urolithiasis in children is microhematuria. According to various specialists, it is encountered as a reason for examination of 1/4 of all children with urolithiasis. Microhematuria can exist for a long time as the only symptom of urolithiasis. Episodes of "asymptomatic" macrohematuria, such as manifestations of urolithiasis, in children occur 2 times less often than microhematuria. Possible clinical manifestations of urolithiasis in children may be dysuria, as well as daytime incontinence (incontinence) of urine. Among the reasons for examination leading to the diagnosis of urolithiasis in young children, such as "unmotivated" fever, persistent anorexia, poor weight gain are less common.

Among the causes of stone formation in young children, congenital anomalies that disrupt urodynamics and contribute to urinary stagnation are second only to urinary tract infection. Urolithiasis is combined with anatomical anomalies with a frequency of 32 to 50% of cases.

With age, the role of metabolic disorders and "idiopathic" stones increases. In older children, as in adults, oxalate-calcium stones predominate (more than 60% of all stones). There is no direct connection between stone formation and the level of oxalate excretion in urine. Oxalate stones do not form for many years with excessive excretion of oxalates in urine (more than 1.5-2 mg/kg per day), but they can form and recur with persistently normal excretion of oxalates.

Thus, urolithiasis occurs and can be diagnosed in children of any age. In young children, the factors contributing to the formation of stones in the urinary tract are infection, especially by microorganisms that break down urea to form urate and phosphate-calcium stones, as well as impaired urodynamics due to congenital anomalies in the development of the urinary tract. Symptoms of urolithiasis in young children have their own characteristics: the relative rarity of typical renal colic, episodes of painless macrohematuria, prolonged microhematuria, many months and even years preceding the passage of stones. There is no parallelism between the level of salt excretion and the intensity of stone formation.