Kidney stones – causes, medical treatment
In terms of biochemical, the urine is a complex solution, saturated with organic, inorganic and mixed salts. They are in a very unstable equilibrium dependent of general concentration, of each component and of their relative proportion and the presence of substances which prevent precipitation.
Regarding the site of stones formation, there are several theories:
– Accumulation of lithogenic material on the basal membrane of the collecting tubules or renal papilla;
– Deposition of lithogenic material in lymphatics from around the collecting tubules followed by lymphatics warping, breaking lymphatics and entering into the urinary ways of lithiasis fragments.
The most common favoring causes of lithogenesis are:
– Metabolic abnormalities: hyperparathyroidism, secondary or idiopathic hypercalciuria, hyperoxaluria, hyperuricosuria, cystinuria, renal tubular acidosis;
– Congenital or acquired anatomic abnormalities of the urinary tract which favor urinary stasis (diverticulas, pielo-ureteric junction stenosis, horseshoe kidney, ureteral stenosis, vesicoureteral reflux).
– Microscopic anatomical abnormalities such as Carr corpuscles or Randall plates.
– Urinary infection, especially with germs that splits urea into ammonia, lower urine pH and generates amoniaco-magnesium phosphate stones.
– Medical treatments: acetazolamide, sulfonamides, vitamin C in megadoses (over 4g/zi), calcium and vitamin D supplements administered improperly.
Medical therapy is indicated for renal colic, eliminable stones or lithogenesis.
In renal colic is indicated the administration of analgesics and antispasmodics as injection (im) or perfusion. Parenteral fluid intake must be ensured (iv) in the period in which the oral way is impossible because of vomiting. Opioids are not indicated due to ureteral spasm they can induce. Also you should not use diuretics which may exacerbate the distension and amplify the pain.
After the colic stops, depending on the outcome of investigations on the size and shape of the stones and urinary condition, if is considered to be an eliminable stone the antispasmodics are interrupted and the therapy is continued with NSAID, while forcing diuresis by administering orally 3-4 liters of liquid. This attitude (anti-inflammatory treatment) is justified by pathophysiological natural way to remove gallstones. It is an active process conducted by the ureter peristalsis. The anti-inflammatory therapy gives a sufficient analgesic post-colic effect, but unlike antispasmodic, it didn’t paralyzes the ureter peristalsis.
Being a disease with a very high potential for recurrence, the disease must have a program of prevention of recurrence. It includes general measures and specific measures.
Diuresis cure is the only prophylactic measure that has proven through randomized trials and is useful in preventing stones formation. The explanation is that in dilute urine the probality for urinary constituents to precipitate is very low. The fluid intake should be enough to produce a diuresis of over 2000 l / day.
Hygienic and dietary regimen – involves correction of lifestyle and eating habits especially. Eating balanced with all food principles, without excesses and without food ban (except for situations that require categorically certain restrictions on food) and avoiding obesity are sufficient in preventing urinary lithogenesis.