Clinical Aspects Multiple Myeloma patients may show various clinical alterations that, almost always, are not specific for MM, making it necessary to do some specific exams to confirm the disease. Interleukin-6 may have an important role in osteoclast activation, and so, in bone reabsortion. Because of low bone density, the occurence of pathologic fractures is common. Expansive lesions can be found through physical examination. Because of the great bone reabsortion, another common problem is hypercalcemia that may lead to renal alterations and neurologic symptoms if not treated.
Recurrent infections is the second big problem.
Pneumonia and pyelonephritis are the most frequent. The cause of these infections is the fact in MM there is a clonal production of one type of non-functioning antibody, and so, there is little production of normal antibodies. So, the great defect on immunity in Myeloma is in opsonization and humoral immunity. Encapsuled bacteria are the most prevalent pathogens because they need opsonization to be phagocytized by reticular-endothelial system cells. Half of the M.M patients have renal pathology.