[Diabetic osteopathy. 4. Laboratory findings]

The authors investigated in a group of 38 subjects with type I diabetes and 222 subjects with type II diabetes laboratory values indicating the level of bone metabolism: calcium, phosphorus, alkaline phosphatase activity in serum, urinary calcium excretion, and they compared the values mutually and with the level of bone mineralization. The authors found significantly lower serum calcium values in all investigated groups, the lowest ones in women with type II diabetes. To these values corresponded always reduced values of bone mineralization which were also lowest in women with type II diabetes. The very lowest bone mineralization was found in groups of subjects treated with oral antidiabetics, the values in women being lower than in men. The authors found also a higher alkaline serum phosphatase activity, in particular of its bone isoenzyme. The significant correlation between the reduced serum calcium value and bone mineralization indicates that this laboratory value has a decisive influence and importance in the development of osteoporosis. The high alkaline phosphatase activity suggests that there is also prescut osteomalacia.