The age of the patient and the severity of the problem affect both the need for and the kind of prophylaxis.
Idiopathic stone-formers
Where no metabolic abnormality is detected, the basis of prevention is continuation of a high intake of fluid all through the day and night. The aim should be to make sure a daily urine volume of 2-2.5 L, which requires a fluid intake in surplus of this, considerably so in the case of those who live in hot countries or work in a hot surroundings.
Idiopathic hypercalciuria
Severe dietary calcium restriction is unsuitable. Patients should be encouraged to eat a normal-calcium (30 mmol/day) diet. Dietary calcium limit results in hyper absorption of oxalate, and so foods containing excessive amounts of oxalate should also be restricted. A high fluid drinking is recommended as for idiopathic stone-formers. Patients who reside in a hard water region may benefit from intake of softened water. If hypercalciuria persists and stone formation continues, a thiazide diuretic is used (e.g. bendroflumethiazide 2.5 or 5 mg every morning). Thiazides decrease urinary calcium excretion by a direct action on the renal tubule. Thiazides may precipitate diabetes mellitus or gout and worsen their hyper cholesterolaemia. Decrease the intake of animal proteins to 50 g/day and sodium intake to 50 mmol/day is also advisable, as a randomized controlled trial has found that a diet restricted in animal protein and salt but with normal calcium was more effective in the prevention of calcium and particularly oxalate stones than a diet restricted in calcium.
Mixed infective stones
Recurrent stones of these kinds should be prevented by continuance of a high fluid drinking and scrupulous control of bacteriuria. This will need long-term follow-up and frequently the use of long-term low-dose prophylactic antibacterial drugs.
Uric acid stones
Dietary measures are probably of negligible value and are hard to put into practice. Successful prevention can be achieved by the long-term use of allopurinol to preserve the serum urate and urinary uric acid excretion in the physilogical range. A high fluid drinking should also be continued. Uric acid is more soluble at alkaline pH, and long term sodium bicarbonate supplementation to preserve an
alkaline urine is an substitute approach in those few patients, who are not capable to take allopurinol. However, alkalinization of the urine favors precipitation of
calcium oxalate and phosphate.
Cystine stones
These can be prevented and indeed will dissolve slowly with a high fluid intake. Five litres of water has to be drunk each 24 hours, and the patient must wake twice in the night to drink 500 ml or more of water. Many patients cannot accept this regimen. An alternative, though in fact more bothersome, option is the long-term intake of the chelating agent penicillamine; this helps cystine to be transformed to the more soluble penicillamine-cysteine complex. Side-effects of penicillamine are drug rashes, blood dyscrasias and immune complex-mediated glomerulonephritis. However, it is especially effective fo the dissolution of the existing cystine stones.
Mild hyperoxaluria with calcium oxalate stones
A high fluid ingestion and dietary oxalate constraint are necessary. Dietary advice as in hypercalciuria is to be followed.
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Stones in kidneys, ureter and urinary bladder
Symptoms of urinary stones
Investigations and treatment of urinary stones
Investigation to detect the causes of urinary stones
How to prevent urinary stone formation
Showing posts with label Renal stone. Show all posts
Showing posts with label Renal stone. Show all posts
Monday, April 6, 2009
Friday, April 3, 2009
Investigations and treatment of urinary stones
Investigations of Urinary stones
The investigations should include a mid-stream specimen of urine for culture and measurement of serum urea, electrolyte, creatinine and calcium levels.
Plain abdominal X-ray and excretion urography are still used widely for diagnosis, although unenhanced helical (spiral) CT is the best diagnostic test available.
Ureteric stones can be missed by ultrasound. Pure uric acid stones are radiolucent. Mixed infective stones in which organic matrix predominates are barely radiopaque. Calcium containing and cystine stones are radiopaque. Calculi overlying bone are easily missed. Staghorn calculi may be missed if the plain abdominal X-ray carried out before contrast injection during urography is not inspected. Uric acid stones may present as a filling defect after injection of contrast medium . Such stones are readily seen on CT scanning.
When excretion urography is carried out during the episode of pain; a normal urogram excludes the diagnosis of pain due to calculous disease. The urine of the patient should be passed through a sieve to trap any calculi for chemical analysis.
Treatment of urinary stones:
Adequate analgesia should be given. An NSAID, e.g. diclofenac 75 mg by i.v. infusion, compares favourably with pethidine and does not cause nausea. Stones less than 0.5 cm diameter usually pass spontaneously. Stones greater than 1 cm diameter usually require urological or radiological intervention. Extracorporeal shock wave lithotripsy (ESWL) will fragment most stones, which then pass spontaneously. Ureteroscopy with a Yag laser can be used for larger stones. Percutaneous nephrolithotomy is also used. Open surgery is rarely needed.
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
The investigations should include a mid-stream specimen of urine for culture and measurement of serum urea, electrolyte, creatinine and calcium levels.
Plain abdominal X-ray and excretion urography are still used widely for diagnosis, although unenhanced helical (spiral) CT is the best diagnostic test available.
Ureteric stones can be missed by ultrasound. Pure uric acid stones are radiolucent. Mixed infective stones in which organic matrix predominates are barely radiopaque. Calcium containing and cystine stones are radiopaque. Calculi overlying bone are easily missed. Staghorn calculi may be missed if the plain abdominal X-ray carried out before contrast injection during urography is not inspected. Uric acid stones may present as a filling defect after injection of contrast medium . Such stones are readily seen on CT scanning.
When excretion urography is carried out during the episode of pain; a normal urogram excludes the diagnosis of pain due to calculous disease. The urine of the patient should be passed through a sieve to trap any calculi for chemical analysis.
Treatment of urinary stones:
Adequate analgesia should be given. An NSAID, e.g. diclofenac 75 mg by i.v. infusion, compares favourably with pethidine and does not cause nausea. Stones less than 0.5 cm diameter usually pass spontaneously. Stones greater than 1 cm diameter usually require urological or radiological intervention. Extracorporeal shock wave lithotripsy (ESWL) will fragment most stones, which then pass spontaneously. Ureteroscopy with a Yag laser can be used for larger stones. Percutaneous nephrolithotomy is also used. Open surgery is rarely needed.
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
Symptoms of urinary stones
Most people with urinary tract calculi are asymptomatic. Pain is the most common symptom and may be sharp or dull, constant, intermittent or colicky. When urinary tract obstruction is present, measures that increase urine volume, such as copious fluid intake or diuretics, including alcohol, make the pain worse.
Clinical features of urinary tract stones
Physical exertion may cause mobile calculi to move, precipitating pain and, occasionally, haematuria (blood in the urine) . Ureteric colic occurs when a stone enters the ureter and either obstructs it or causes spasm during its passage down the ureter. This is one of the most severe pains known. Radiation from the flank to the to the lower abdomen and testis or labium in the distribution of the first lumbar nerve root is common. Pallor, sweating and vomiting often occur and the patient is restless, tending to assume a variety of positions in an unsuccessful attempt to obtain relief from the pain. Haematuria often occurs. Untreated, the pain of ureteric colic typically subsides after a few hours. When urinary tract obstruction and infection are present, the features of acute pyelonephritis or of a Gram negative septicaemia may dominate the clinical picture.
Vesical calculi associated with bladder bacteriuria may present with frequency, dysuria and haematuria; severe introital or perineal pain may occur. A calculus at the bladder neck or an obstruction in the urethra may cause bladder outflow obstruction, resulting in anuria (complete stoppage of urine) and painful bladder distension.
History of the following is often present:
-occupation and residence in hot countries likely to be associated with dehydration
-a history of vitamin D consumption
-gouty arthritis.
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
Clinical features of urinary tract stones
Physical exertion may cause mobile calculi to move, precipitating pain and, occasionally, haematuria (blood in the urine) . Ureteric colic occurs when a stone enters the ureter and either obstructs it or causes spasm during its passage down the ureter. This is one of the most severe pains known. Radiation from the flank to the to the lower abdomen and testis or labium in the distribution of the first lumbar nerve root is common. Pallor, sweating and vomiting often occur and the patient is restless, tending to assume a variety of positions in an unsuccessful attempt to obtain relief from the pain. Haematuria often occurs. Untreated, the pain of ureteric colic typically subsides after a few hours. When urinary tract obstruction and infection are present, the features of acute pyelonephritis or of a Gram negative septicaemia may dominate the clinical picture.
Vesical calculi associated with bladder bacteriuria may present with frequency, dysuria and haematuria; severe introital or perineal pain may occur. A calculus at the bladder neck or an obstruction in the urethra may cause bladder outflow obstruction, resulting in anuria (complete stoppage of urine) and painful bladder distension.
History of the following is often present:
-occupation and residence in hot countries likely to be associated with dehydration
-a history of vitamin D consumption
-gouty arthritis.
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
Stones in the kidneys, ureters and urinary bladder – Types and causes
Renal and urinary bladder stones (calculi)
Urinary stone is a fairly common throughout the world particularly in the Middle East. Most urinary stones are composed of calcium oxalate and phosphate; these are more common in men. Mixed infective stones, which account for about 15% of all calculi, are twice as common in women as in men. The overall male to female ratio of stone disease is 2 :1. Stone disease is frequently a recurrent problem. More than 50%of patients with a history of nephrolithiasis will develop a recurrence within 10 years. The risk of recurrence increases if a metabolic or other abnormality predisposing to stone formation is present and is not modified by treatment.
Composition of urinary stones
Calcium oxalate usually with calcium phosphate - 65%
Calcium phosphate alone – 15%
Magnesium ammonium phosphate (struvite) -10-15%
Uric acid 3-5%
Cystine 1-2%
How urinary stone is formed?
Inhibitors of crystal formation are present in normal urine preventing the formation of stones, as the concentrations of stone-forming substances exceed their maximum solubility in water. Many stone-formers have no detectable metabolic defect, although microscopy of warm, freshly passed urine reveals both more and larger calcium oxalate crystals than are found in normal subjects. Factors predisposing to stone formation in these so-called 'idiopathic stone-formers' are:
#chemical composition of urine that favors stone crystallization
#production of a concentrated urine as a consequence of dehydration associated with life in a hot climate or work in a hot environment
#impairment of inhibitors that prevent crystallization in normal urine.
Causes of urinary stone formation:
Hypercalcaemia
If the GFR is normal, hypercalcaemia almost invariablyleads to hypercalciuria. The common causes of hypercalcaemia leading to stone formation are:
primary hyperparathyroidism
vitamin D ingestion
sarcoidosis.
The other causes of stone formation are:
Dehydration
Hypercalciuria
Hyperoxaluria
Hyperuricaemia and
hyperuricosurea
Infection
Cystinuria
Renal tubular acidosis
Primary renal disease(polycystic kidneys, medullary sponge kidneys)
Drugs
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
Urinary stone is a fairly common throughout the world particularly in the Middle East. Most urinary stones are composed of calcium oxalate and phosphate; these are more common in men. Mixed infective stones, which account for about 15% of all calculi, are twice as common in women as in men. The overall male to female ratio of stone disease is 2 :1. Stone disease is frequently a recurrent problem. More than 50%of patients with a history of nephrolithiasis will develop a recurrence within 10 years. The risk of recurrence increases if a metabolic or other abnormality predisposing to stone formation is present and is not modified by treatment.
Composition of urinary stones
Calcium oxalate usually with calcium phosphate - 65%
Calcium phosphate alone – 15%
Magnesium ammonium phosphate (struvite) -10-15%
Uric acid 3-5%
Cystine 1-2%
How urinary stone is formed?
Inhibitors of crystal formation are present in normal urine preventing the formation of stones, as the concentrations of stone-forming substances exceed their maximum solubility in water. Many stone-formers have no detectable metabolic defect, although microscopy of warm, freshly passed urine reveals both more and larger calcium oxalate crystals than are found in normal subjects. Factors predisposing to stone formation in these so-called 'idiopathic stone-formers' are:
#chemical composition of urine that favors stone crystallization
#production of a concentrated urine as a consequence of dehydration associated with life in a hot climate or work in a hot environment
#impairment of inhibitors that prevent crystallization in normal urine.
Causes of urinary stone formation:
Hypercalcaemia
If the GFR is normal, hypercalcaemia almost invariablyleads to hypercalciuria. The common causes of hypercalcaemia leading to stone formation are:
primary hyperparathyroidism
vitamin D ingestion
sarcoidosis.
The other causes of stone formation are:
Dehydration
Hypercalciuria
Hyperoxaluria
Hyperuricaemia and
hyperuricosurea
Infection
Cystinuria
Renal tubular acidosis
Primary renal disease(polycystic kidneys, medullary sponge kidneys)
Drugs
Causes of Urinary stone formations
Symptoms of urinary stones
Investigations and treatment of urinary stones
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