Therefore, I believe it is better to neuter a male cat after he has reached his adult stature rather than too young. If he is neutered at too young an age the penis and urethra remain infantile combined with the lack of testosterone, the male hormone. The smaller urethra then is more prone to blockage. Older cats of both sexes can develop uroliths as well. If the uroliths become too large they cannot be passed and will continue to grow in the bladder or become lodged in the urethra.
Large uroliths have to be removed surgically.
Some rural water supplies for drinking and crop production contain high levels of the offending minerals that can lead to these problem. Poor quality dry cat foods, which contain low amounts of animal products and large amounts of plant products, fed over extended lengths of time, may also contribute to this problem as the urine becomes less acidic. A lack of sufficient good quality drinking water may contribute with the cat not drinking enough to flush out any offending crystals and the water may in fact be high in minerals prone to crystallization. Acidifying the urine also helps. Ascorbic acid or vitamin C supplementation and low ash diets are in order.