Such factors as high levels of immunoglobulin E and pregnancy-specific 1-glycoprotein (PSG) appear as diagnostic criteria for both bone malignancies and acute hematogenous osteomyelitis. It was found that significant increase in blood-serum PSG in conjunction with lowered IgE is a marker of bone malignancy while decreased PSG and high IgE is that of acute hematogenous osteomyelitis.