The ammonia smell
in urine as described by you, sometimes occurs
in kidney diseases, when
it is described as fishy smell. If the liver is decompromised it cannot metabolize the waste products hence there is an elevation of blood ammonia levels resulting in increased excretion in the urine. Also, increased levels of ammonia may also be seen with gastrointestinal bleeding, where the blood cells are haemolysed in the intestines, releasing protein.