Complex sentence: Some individuals with this disease develop gout, which is a condition in which patients develop severe pain and swelling in the big toe or another joint such as the knee, if untreated, it becomes chronic and affects the joints most of the time instead of intermittently.
Split into simpler sentences: Some individuals with this disease develop gout, which is a condition in which patients develop severe pain and swelling in the big toe or another joint such as the knee. If untreated, it becomes chronic and affects the joints most of the time, instead of intermittently.