Final answer:
Calcium oxalate stones are the most common type of urinary tract calculi, and they frequently obstruct the ureter. Low-calcium diets can lead to a higher risk of these stones by increasing oxalate absorption and excretion into the urine.
Step-by-step explanation:
The most common type of urinary tract calculi that frequently obstruct the ureter are calcium oxalate stones. These stones form when calcium combines with oxalate in the urine. Factors such as a low-calcium diet can increase the risk of developing these stones since dietary calcium binds oxalate in the gastrointestinal tract, preventing its absorption and later excretion into the urine. When the oxide concentration increase in the urine, it promotes the precipitation of calcium oxalate, potentially leading to kidney stone formation.
Kidney stones vary in size and a larger stone can block the ureter, leading to severe pain, potential kidney damage, and the need for medical intervention. Although calcium phosphate stones are also a common type of kidney stone, related to conditions such as hyperparathyroidism and renal tubular acidosis, the calcium oxalate stones are more common.