Complex sentence: Because most diabetecs are treated before this stage, it is very rare to see it at the present time; it appears in decompensated diabetics with glycemia superior to 500 mg/dL and severe glycosuria; it is a reversible alteration without functional manifestations.
Split into simpler sentences: Because most diabetecs are treated before this stage, it is very rare to see it at the present time. It appears in decompensated diabetics with glycemia higher than 500 mg/dL and severe glycosuria; it is a reversible alteration without functional manifestations.