Calculous Disease Of The Kidney And Ureters...
Renal calculi form in the collecting system of the kidney as concretions of substances normally present in solution in the urine. The common sub-stances which give rise to stone formation are calcium oxalate, calcium phosphate and uric acid. Rare stones are made of cystine and xanthine. The reason why the majority of stones form is not known. A proportion occur because of poor drainage in the urinary collecting system leading to stasis and infection, whilst a small proportion form when excessive calcium is excreted into the urine in the metabolic disorder hyperthyroidism.. Stone formation is also related to poor fluid intake, especially in hot climates; the urine becomes highly concentrated and the crystallized substances in the urine become easily precipitated.
The stones form first in relation to the renal papillae in the calyxes and may gradually increase in size to fill the whole renal pelvis—the so-called 'stag horn' or 'cast calculus'. Symptoms depend upon the size and mobility of the calculi. Small calculi remaining wedged' in a calyx are usually symptomless, but small calculi which become dislodged into the pelvis' or ureter cause considerable pain and give rise to the condition of ureteric colic as they pass down the ureter to the bladder.
Large stones are usually symptomless unless they become wedged in•the pelvic-ureteric junction, when they may cause considerable loin pain and back pressure with hydro-nephrotic destruction of the kidney. If such a hydronephrotic kidney becomes infected then the whole organ may be converted into a large closed abscess or pyonephrosis.
Medical treatment is to encourage a high fluid intake and to correct any metabolic cause for further stone formation such as hyperparathyroidism and to remove any persistent cause of infection. There is little evidence that adherence to any particular type of diet is important in the prevention of stone recurrence as long as a high fluid intake maintains a dilute urine. Medical treatment of the acute attack of ureteric colic is to administer
CALCULOUS DISEASE OF THE KIDNEY AND URETERS 531
a high fluid load to induce diuresis and to relieve pain with strong analgesics such as pethidine at frequent intervals. Antispasmodic drugs such as Pro-Banthine or atropine are also used in an attempt to relax the smooth muscle of the ureter.
Surgical treatment. Most stones of less than 0.5 cm in diameter will be passed spontaneously down the ureter into the bladder. Ureteric colic is usually occasioned during this passage and surgical removal is only contemplated if the calculi become arrested at any point. If the stone be¬comes stuck within the lower two inches of the ureter it may be dislodged by passing an endoscopic stone extractor (Dormia basket) into the ureter through a cystoscope. Stones wedged higher in the ureter must be removed by open operation, ureterolithotomy.
Renal stones are usually removed from the kidney if they are causing obstruction, recurrent infection or renal pain. The stones may be removed from the pelvis of the kidney by pyelolithotomy or through the renal substance by nephrolithotomy.
Renal calculi form in the collecting system of the kidney as concretions of substances normally present in solution in the urine. The common sub-stances which give rise to stone formation are calcium oxalate, calcium phosphate and uric acid. Rare stones are made of cystine and xanthine. The reason why the majority of stones form is not known. A proportion occur because of poor drainage in the urinary collecting system leading to stasis and infection, whilst a small proportion form when excessive calcium is excreted into the urine in the metabolic disorder hyperthyroidism.. Stone formation is also related to poor fluid intake, especially in hot climates; the urine becomes highly concentrated and the crystallized substances in the urine become easily precipitated.
The stones form first in relation to the renal papillae in the calyxes and may gradually increase in size to fill the whole renal pelvis—the so-called 'stag horn' or 'cast calculus'. Symptoms depend upon the size and mobility of the calculi. Small calculi remaining wedged' in a calyx are usually symptomless, but small calculi which become dislodged into the pelvis' or ureter cause considerable pain and give rise to the condition of ureteric colic as they pass down the ureter to the bladder.
Large stones are usually symptomless unless they become wedged in•the pelvic-ureteric junction, when they may cause considerable loin pain and back pressure with hydro-nephrotic destruction of the kidney. If such a hydronephrotic kidney becomes infected then the whole organ may be converted into a large closed abscess or pyonephrosis.
Medical treatment is to encourage a high fluid intake and to correct any metabolic cause for further stone formation such as hyperparathyroidism and to remove any persistent cause of infection. There is little evidence that adherence to any particular type of diet is important in the prevention of stone recurrence as long as a high fluid intake maintains a dilute urine. Medical treatment of the acute attack of ureteric colic is to administer
CALCULOUS DISEASE OF THE KIDNEY AND URETERS 531
a high fluid load to induce diuresis and to relieve pain with strong analgesics such as pethidine at frequent intervals. Antispasmodic drugs such as Pro-Banthine or atropine are also used in an attempt to relax the smooth muscle of the ureter.
Surgical treatment. Most stones of less than 0.5 cm in diameter will be passed spontaneously down the ureter into the bladder. Ureteric colic is usually occasioned during this passage and surgical removal is only contemplated if the calculi become arrested at any point. If the stone be¬comes stuck within the lower two inches of the ureter it may be dislodged by passing an endoscopic stone extractor (Dormia basket) into the ureter through a cystoscope. Stones wedged higher in the ureter must be removed by open operation, ureterolithotomy.
Renal stones are usually removed from the kidney if they are causing obstruction, recurrent infection or renal pain. The stones may be removed from the pelvis of the kidney by pyelolithotomy or through the renal substance by nephrolithotomy.
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