Calculi, renal

Litholytic agents in current use are classified as direct or indirect. Indirect type drugs decrease the C.P. of urine, thus inhibiting calculus formation. An example is citrate which helps prevent insoluble salts from crystallizing in the urinary tract. Potassium citrate is administered in pill form as a preventive drug. Direct type drugs dissolve renal calculi which have already formed. 

Calcium-containing antacids—rebound hyperacidity, metabolic alkalosis, hypercalcemia, vomiting, confusion, headache, renal calculi, and neurologic impairment... 

Postrenal ARF is due to obstruction of urinary outflow. Causes include benign prostatic hypertrophy, pelvic tumors, and precipitation of renal calculi.7 Rapid resolution of postrenal ARF without structural damage to the kidney can occur if the underlying obstruction is corrected. Postrenal ARF accounts for less than 10% of cases of ARF.6... 

Zonisamide Modulate sodium and calcium channels Loading dose Not recommended due to excessive adverse effects Maintenance dose 1 00-600 mg/day start at 100 mg/day and titrate upward as indicated by response Half-life 63 hours Apparent volume of distribution 1.45 L/kg Protein binding 40% Primary elimination route Hepatic Not established Dizziness, somnolence Metabolic acidosis, oligohidrosis, paresthesias, renal calculi... 

Nephrolithiasis A condition marked by the presence of renal calculi (stones) in the kidney or urinary system. 

The major side effects associated with uricosuric therapy are GI irritation, rash and hypersensitivity, precipitation of acute gouty arthritis, and stone formation. These drugs are contraindicated in patients who are allergic to them and in patients with impaired renal function (CLcr <50 mL/min) or a history of renal calculi, and in patients who are overproducers of uric acid. 

Renal calculi occurred in 2 children being treated with a low-galactose diet (B7, C5). In one case it was shown that the serum alkali reserve was low (B7). It is impossible to decide whether this was due to galactose damaging the kidney and causing continued dysfunction after exposure to galactose had stopped, or to some characteristic of the low-galactose diet. 

Q68 Severe pain in one loin, which may last several hours and recur at intervals of days requires referral. The patient needs to be assessed for the occurrence of renal calculi. 

Severe pain in the loin lasting several hours and which is recurring requires referral to investigate underlying cause. One of the systems that need to be investigated is the renal system. Pain originating from kidney disorders and renal colic (renal calculi) initially presents with loin pain and may radiate to the back or spread downwards to the iliac fossa, suprapubic area and in males into the scrotum. 

Excessive vitamin C doses Diabetics, patients prone to recurrent renal calculi, those undergoing stool occult blood tests and those on sodium restricted diets or anticoagulant therapy should not take excessive doses of vitamin C over an extended time period. 

Renal calculi Recent studies show that high dietary intake of calcium decreases the risk of symptomatic renal calculi, while intake of supplemental calcium may increase the risk of symptomatic stones. This conflicts with the previous theory that high calcium intake contributes to the risk of renal calculi. 

Adverse reactions associated with probenecid therapy include occasional rashes, allergic dermatitis, upper gastrointestinal tract irritation, and drowsiness. The drug is contraindicated in patients with a history of renal calculi. 

Contraindications Calcium renal calculi, digoxin toxicity, hypercalcemia, hypercalci-uria, sarcoidosis, ventricular fibrillation... 

Unlabeled Uses Treatment of diabetes insipidus, prevention of calcium-containing renal calculi... 

Metabolic acidosis, electrolyte imbalance, transient myopia, urticaria, melena, hematuria, glycosuria, hepatic insufficiency, flaccid paralysis, photosensitivity convulsions, and rarely crystalluria, renal calculi... 

Mechanism of Action A heavy metal antagonist that chelates copper, iron, mercury, lead to form complexes, promoting excretion of copper. Combines with cystine-forming complex, thus reducing concentration of cystine to below levels for formation of cystine stones. Exact mechanism for rheumatoid arthritis is unknown. May decrease cell-mediated immune response. May inhibit collagen formation. Therapeutic Effect Promotes excretion of copper, prevents renal calculi, dissolves existing stones, acts as anti-inflammatory drug. 

Assess the patient for signs and symptoms of hypercalcemia, including constipation, deep bone or flank pain, excessive thirst, hypotonicity of muscles, increased urine output, nausea and vomiting, and renal calculi... 

Gout is a metabolic disease characterized by recurrent episodes of acute arthritis due to deposits of monosodium urate in joints and cartilage. Uric acid renal calculi, tophi, and interstitial nephritis may also occur. Gout is usually associated with hyperuricemia, high serum levels of uric acid, a poorly soluble substance that is the major end product of purine metabolism. In most mammals, uricase converts uric acid to the more soluble allantoin this enzyme is absent in humans. While clinical gouty episodes are associated with hyperuricemia, most individuals with hyperuricemia may never develop a clinical event from urate crystal deposition. 

For example, normal urine is supersaturated with calcium oxalate. To prevent formation of renal calculi (stones)719 an inhibitory glycoprotein is present and slows the formation and growth of crystals.720 Under some disease conditions calcium carbonate stones may form in pancreatic ducts. A17 kDa lectinlike glycoprotein called lithostatine has been proposed to inhibit stone formation by binding to certain planes on CaC03 microcrystals just as antifreeze proteins (Box 4-D) inhibit ice formation.721 However, this proposed function for lithostatine is doubtful.722 723 Pathological deposits of crystalline calcium pyrophosphate and basic calcium phosphates are sometimes present in joints,724 even in Neanderthal skeletons.725... 

Of nutrient chelates in the human diet, oxalates and phytules arc Ihe most common. Oxalic acid, found principally in spinach, rhubarb leaves, beet leaves, some fruits, and mushrooms, is u primary chelator of calcium. Oxalate present in pineapple, kiwifmil, and possibly in other foods, occurs as calcium oxalale. CaCiOj. This compound is in the form of needle-like crystals, known as raphidcs. which can produce painful sensations in the mouth when eaten raw. The effects of oxalic acid in the diet may he twofold. First, it forms strong chelates with dietary calcium, rendering the culcium unavailable for absorption and assimilation. Secondly, absorbed oxalic acid causes assimilated Ca to be precipitated as insoluble salts that accumulate in the renal glomeruli and contribute to the formation of renal calculi. 

Allopurinol is used in the treatment of hyperuricemia, which is associated with chronic gout and in cancer chemotherapy. Allopurinol has been used in renal calculi caused by the deposition of calcium oxalate and of 2,8-dihydroxy-adenine. Allopurinol treatment does cause hypersensitivity reaction, which may be fatal. 

The commercial products, sporting paper caps (SPC potassium chlorate, red phosphorus and sulfur), toy paper caps (same components as SPC) and silver azide cartridges for breaking renal calculi have lower sensitivity than their powdery components because they are packaged as cartridges. 

Hypokalemia Renal calculi Blood dyscrasias Dermatitis... 

Acetazolamide may precipitate renal calculi formation in predisposed individnals. Therefore patients with bacterinria, previons bladder snrgery, or a history suggestive of previous calculus formation should not... 

Methazolamide is particularly useful in patients predisposed to develop renal calculi. Methazolamide interferes less with excretion of urinary citrate, which may explain why kidney stones have only rarely been associated with its use. 

Systemic side effects reported with oral CAIs have generally not been seen with topical CAIs. Paresthesias, electrolyte imbalance, and CNS side effects, including malaise and fetigue, have not been reported with dorzolamide. Bitter taste is experienced in approximately 25% of patients taking topical dorzolamide. Three cases of nephrolithiasis have been attributed to topical dorzolamide. Onset was from 21 days to 8 months after treatment began. Two patients, however, had previously received systemic CAIs. Because there may be an increased risk of developing nephrolithiasis, a careful history of renal calculi should be obtained. 

Adverse effects. High doses of acetazolamide may cause drowsiness and fever, rashes and paraesthesiae may occur, and blood disorders have been reported. Renal calculi may develop, because the urine calcium is in less soluble form owing to low citrate content of the urine, a consequence of metabolic acidosis. 

Symptoms of overdose are due mainly to excessive rise in plasma calcium. General effects include malaise, drowsiness, nausea, abdominal pain, thirst, constipation and loss of appetite. Other long-term effects include ectopic calcification almost anywhere in the body, renal damage and an increased calcium output in the urine renal calculi may be formed. It is dangerous to exceed 10 000 units daily of vitamin D in an adult for more than about 12 weeks. 

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