Urinary tract stones are both an ancient disease and an important problem in modern medicine. With the improvement of people’s living standards, the number of patients suffering from urinary tract stones is increasing year by year. The human urinary system includes: kidney, ureter, bladder, and urethra. Stones that occur in these organs are called urinary stones (urolithiasis for short). Clinically, kidney and ureteral stones are usually referred to as upper urinary tract stones, and bladder and urethra stones are referred to as lower urinary tract stones. Urolithiasis, if not diagnosed and treated in a standardized manner, will not only cause unnecessary financial losses to patients, but also bring about serious consequences. Although, there are new advances and new methods in the treatment of urinary tract stones, they have not reduced the incidence and recurrence rate of urinary stones.
I. Etiology of urinary stones
The formation of stones is related to the natural environment (geographical location, climatic factors, water quality, etc.), social and environmental factors (food and nutritional status), ethnic genetic factors, abnormalities in the transmission of human metabolites, as well as the causes of the urinary system itself (such as obstruction, infection, foreign body retention) and the increase in the content of stone promoters, inhibiting stone formation inhibitors or lack of factors etc. are all related to the formation of urolithiasis.
Clinical manifestations of urinary tract stones
Urolithiasis can be divided into upper urinary tract stones and lower urinary tract stones. The clinical manifestations of upper and lower urinary tract stones are different because of the location of the stones.
Generally speaking, upper urinary tract stones (kidney and ureter) mainly manifest as pain and hematuria. The pain often occurs suddenly, mostly in the middle of the night or early in the morning. The pain is severe and unbearable, and the patient often tosses and turns, sweating profusely, pale, nauseous and vomiting. The pain is mostly located in the lower back and abdomen and radiates to the perineum or the inner thigh of the same side. There may be visual or microscopic hematuria after activity. If the stone is accompanied by infection, there may be symptoms such as frequent urination and painful urination, and if the stone is secondary to pyelonephritis or cumulus, there may be systemic symptoms such as fever, chills and shivering.
When the upper urinary tract stones are completely obstructed bilaterally, it can lead to anuria.
Bladder stones can be divided into primary and secondary. Primary bladder stones are mostly seen in boys and are associated with malnutrition. Secondary bladder stones are mostly caused by ureteral stones descending from the kidney to the bladder. The presence of obstructive conditions such as prostatic hyperplasia, urethral strictures, bladder diverticula, foreign bodies and neurogenic bladder in elderly men can complicate bladder stones.
Typical clinical manifestations of bladder stones are interruption of urination, with boys often rubbing and pulling the penis with their hands, accompanied by painful urination and frequent and urgent urination, which can be continued after changing position or jumping.
Urethral stones mainly show difficulty in urination, dribbling urination, if the stone is completely obstructed, it can lead to acute urinary retention.
Diagnosis of urinary tract stones
Based on the above clinical manifestations, the possibility of urolithiasis should be thought of. To make a clear diagnosis, the following related examinations are needed.
Ultrasound can make up for the lack of X-rays in the diagnosis (negative stones cannot be detected by X-rays) and can also understand the presence of other diseases in the urinary system (such as hydronephrosis, tumors, malformations, etc.). However, ultrasound is often not easy to detect tiny stones less than 3 mm in the kidney, and it is difficult to diagnose ureteral stones in obese people, so ultrasound cannot be used as the only basis for the diagnosis of urolithiasis.
KUB+IVU not only can understand the location, shape, size and number of stones, but also the presence of hydronephrosis in the kidney, the degree of hydronephrosis, and the presence or absence of hydronephrosis. The KUB+IVU can not only understand the presence of fluid, the degree of fluid, the presence of urinary tract obstruction, the site of obstruction, the functional status of the kidney and the thickness of the renal parenchyma. If ultrasound is combined with abdominal plain film and intravenous urography, it can complement each other and improve the diagnostic accuracy.
3, CT is generally not used as the first choice of urolithiasis examination method, only when the acute renal colic attack, after the pain relief and pain relief and other treatment still can not relieve the symptoms, in order to make a clear diagnosis, CT examination. Spiral CT plain scan can detect stones of 2mm or more (including negative stones). For severe hydronephrosis and non-functioning kidney, it is important to understand the morphology of kidney, cortical thickness and whether to make nephrectomy for non-functioning kidney.
IV. Treatment of urinary tract stones
The standard treatment of urolithiasis should be based on the patient’s general condition, the size, number, location, morphology, presence of obstruction, infection, hydronephrosis, the degree of damage to the renal parenchyma, and the prevention of stone recurrence.
1. Treatment of renal colic.
(1) renal colic is a common acute abdominal disease in urology and requires urgent treatment. First of all, it should be antispasmodic and analgesic. Analgesic drugs are: morphine, dulcolax, prednisone, etc.. Along with analgesia, antispasmodics such as atropine, 654-2, progesterone must be used. There are other analgesics, such as Fotarine, anti-inflammatory pain, etc.
(2) Surgical treatment should be considered when the pain cannot be relieved by drugs or when the stone diameter is larger than 6mm. a. ESWL is preferred; b. ureteral built-in stent tube with ESWL; c. ureteroscopic lithotripsy for stone extraction; d. percutaneous nephrostomy for drainage, especially in cases of severe renal colic due to stone obstruction combined with infection.
2. Treatment of upper urinary tract stones without colic
(1) Generally, it is believed that stones with diameter less than 6mm, smooth surface, no obstruction in the urinary tract below the stone, 80% of stones can be expelled by oral lithotripsy medication and drinking more water (keeping the daily urine volume above 3000ml), combined with jumping exercise, which means that lithotripsy is not needed. In particular, the stone removal rate of lower ureteral stones (<6mm) is more than 98%. If the stone is still not expelled after three weeks of treatment, minimally invasive techniques can be considered for interventional treatment.
(2) ESWL or percutaneous nephrolithotomy (PNL) or combined ESWL+PNC can be considered for kidney stones ≤20 mm in diameter. If ESWL is used alone, it is better to insert a double “J” tube before ESWL to prevent the ureter from being blocked by the “stone street”.
(3) Whether to use ESWL or ureteroscopic lithotripsy for ureteral stones after three weeks of conservative treatment is ineffective has been controversial. For the urologist, the choice of the better treatment depends on his experience, the equipment he has and the treatment environment. For stones with a diameter of more than 1 cm or a rough polygonal surface, or stones that have been embedded for too long causing severe ureteral obstruction and for which non-surgical treatment has failed, the success rate of surgical stone extraction is 100%.
(4) For special types of kidney stones, such as antler-shaped stones, horseshoe stones, arched kidney stones, transplanted kidney stones, diverticulum stones, pediatric kidney stones, stones in overly obese patients, infected stones, cystine stones, etc., what kind of treatment is appropriate depends on the patient’s general condition, stone location, size and shape, the presence of combined infection, obstruction, hydronephrosis, renal function, renal cortical thickness, etc. It is important to make a comprehensive judgment based on the patient’s systemic condition, stone location, size and shape, co-infection, obstruction, fluid retention, renal function, and thickness of the kidney cortex.
It is important to mention that although ESWL can avoid the pain of open surgery in 90% of patients with urinary tract stones, not everyone is suitable for ESWL, especially patients with lower urinary tract stenosis, severe hydronephrosis on the affected side, non-functional patients, patients with poor systemic condition who cannot tolerate the position of ESWL treatment, patients with systemic bleeding tendency or those with urinary tract stones during pregnancy should be considered as contraindications to ESWL. ESWL should be considered as a contraindication. If kidney stones, especially larger ones, such as antler-shaped stones, are repeatedly treated with lithotripsy, they can be complicated by hypertension and renal atrophy. For young patients, especially young men and women of childbearing age, ESWL treatment is in principle contraindicated in view of the side effects of shock waves and X-rays on the reproductive system.
(5) Regarding the treatment of bladder stones, two principles must be followed: one is to remove the stones; the other is to correct the causes and factors of stone formation. Its treatment can be done by lithotripsy or surgical stone extraction.