Diagnosis and treatment of kidney stones

  Urinary stones are one of the common diseases in urology, which can be divided into kidney stones, ureteral stones and bladder stones according to their location.  Kidney stones mostly occur in middle and old age, more in men than in women. Kidney stones may persist for a long time without symptoms, especially larger stones. Smaller stones have a large range of motion, and when a small stone enters the pelvic-ureteral junction or ureter, it causes violent peristalsis of the ureter to induce the stone to expel, whereupon colic and hematuria occur. The pain caused by kidney stones can be classified as dull pain or colic. 40%-50% of patients have a history of intermittent episodes of pain. The pain is often located in the lower back and abdomen, mostly paroxysmal, but can be constant. Some of the pains may only be associated with lower back discomfort, but activity or labor may cause the pain to flare up or worsen. The pain often radiates to the lower abdomen, groin or inner femur, or to the labia in women. During an attack of renal colic, the patient looks acutely ill, curled up in bed, with both hands pressing on the abdomen or waist, or even rolling over in bed, moaning and groaning. The attack often lasts for several hours, but may be relieved in a few minutes. When the renal colic is severe, the face is pale, the whole body has cold sweat, the pulse is thin and rapid, and even the blood pressure drops, showing a state of deficiency, accompanied by nausea, vomiting, abdominal distension and constipation. During the attack of colic, the urine volume decreases, and after the colic is relieved, there may be polyuria.  Hematuria is another major symptom of kidney stones. When painful, it is often accompanied by flesh-eye hematuria or microscopic hematuria, the latter being the most common, and massive flesh-eye hematuria is not uncommon, and hematuria may worsen after physical activity. Patients with kidney stones may excrete sand and stones in the urine, especially during episodes of pain and hematuria, with sand particles or small stones mixed in the urine. Obstruction or stabbing pain occurs when stones pass through the urethra. The common complications of kidney stones are obstruction and infection, and many cases seek medical attention for symptoms of urinary tract infection. Obstruction, in turn, can cause hydronephrosis and a mass in the upper abdomen or lower back.  The diagnosis of kidney stones is generally not difficult and can be confirmed in most cases by history, physical examination and necessary radiographs, and laboratory tests. However, we should not be satisfied with the diagnosis of kidney stones, but should also understand the stone size, number, morphology, location, presence of obstruction or infection, kidney function, stone composition and underlying etiology. If stone analysis is not performed or the examination of stone etiology is abandoned, it often leads to the recurrence of stones that could have been prevented, resulting in more unfavorable consequences.  Ultrasound and urological X-ray are the most commonly used tests to diagnose kidney stones. 90% of kidney stones are visualized on X-ray, and the depth of the visualization is related to the chemical composition, size and thickness of the stones. Stones of different compositions are ranked in order of their satisfactory degree of visualization: calcium oxalate, calcium and magnesium phosphate, cystine, calcium urate, and pure uric acid stones are not visualized. Ultrasound examination is useful for the diagnosis of fluid and stones, especially for asymptomatic stones and uric acid stones that do not show up on X-ray.  Kidney stones can be divided into calcium-containing kidney stones, uric acid stones, infected stones, etc. Calcium-containing kidney stones are mainly calcium oxalate and calcium phosphate, which account for 80%-84% of all urinary stones. Other rare stones, such as those caused by long-term medication, are most likely to form crystals from sulfadiazine, if supplemented with alkalizing urine medication or drinking more water to prevent sulfadiazine crystals from forming.  The purpose of kidney stone treatment is not only to relieve the pain and protect the kidney function, but also to find and relieve the cause of the disease as much as possible to prevent the recurrence of stones. Treatment should include a combination of general treatment, etiology treatment, extracorporeal shock wave lithotripsy, intracorporeal lithotripsy, lithotripsy treatment, surgical treatment, and Chinese medicine treatment. General treatment includes drinking plenty of water and acupuncture therapy. The daily urine volume should be maintained at 2000-3000 ml as much as possible. Drinking large amounts of water together with diuretic and antispasmodic drugs can promote the discharge of small urinary stones. To maintain nighttime urine output, in addition to drinking water before bedtime, it is advisable to drink water again after waking up at night to urinate. Diluted urine slows the growth of stones and the recurrence of stones after surgery. In the presence of infection, a higher volume of urine promotes drainage and facilitates the control of infection. In renal colic, drinking more water may aggravate the colic, but if combined with antispasmodic drugs, it may help the stones to be expelled. If the stone is small and the patient is in good health, physical activity can be used and Chinese and Western drugs can be applied to facilitate the stone’s discharge on its own. In the past decade, there has been a breakthrough in the treatment of kidney stones, and now the common treatment methods are extracorporeal shock wave lithotripsy (ESWL) and endovenous urology, and only a few cases are treated by surgery.