Kidney Stones
- causes and risk factors
- signs, symptoms and diagnosis
- pathophysiology
- treatments
- consequences and course
- the patient
- health care team
- community involvement
- resources and references
Kidney stones are a common source of morbidity. The peak incidence is 20-45 years, with men being more than 5x affected.
Causes and Risk Factors
Incidence is higher in industrialized countries, likely due to high intake of animal protein and low intake of fibre.
Calcium stones are more likely with hypercalemia (hyperthyroidism, sarcoidosis, malignancy, immobilisation), hyperoxalatemia (IBD, diets rich in oxalates such as tea, citrus, spinach, peanuts)
Signs, Symptoms, and Diagnosis
Kidney stones usually lead to hematuria and sudden onset of excruciating colicky pain, originating in the flank and radiating to the groin.
Polyuria, dysuria, vomiting, and ileus can also result.
- History
- Physical Exam
- Labs
History
The history should focus on hematuria, past stones, urinary tract infections, family history, and detailed dietary analysis.
Labs
Initial assessment should include electrolytes, creatinine, serum calcium, phosphate, and uric acid.
Urinalysis can determine level of hematuria, rule out infection, and importantly, determine the type of crystals.
Pathophysiology
There are five types of renal stones (calculi).
Calcium stones are the most common, accounting for 75% of all stones. Most are composed of calcium oxalate, with the rest comprised of calcium phosphate. Calcium phosphate requires an alkalai environment to form.
Magnesium ammonium phosphate, uric acid, and cystine are all less common.
Treatments
Management depends on type of stone, but the majority (~90%) pass spontaneously, though those 8 mm or larger likely require intervention - extracorporeal shock wave lithotripsy or ureteroscopy with basket retrieval.
All patients should drink ~3L daily to ensure at least 2L of urianry volume.
Restricting intake of animal protein and dietary salt reduces the risk of further stones.
Consequences and Course
The Patient
Health Care Team
Community Involvement
References