SKIBO diseases: a concept to avoid bloody diagnostic procedures in ambiguous skeletal lesions.

In cases with an "atypical" radiologic pattern-osteolytic as well as osteosclerotic or mixed - the radiologist should pay attention to the patient's skin. There he will often find specific changes that are the key to a correct interpretation of the radiologic abnormalities. In such cases the synopsis is of more value in differential diagnosis than more or less unspecific histologic findings. Entities with a non-arbitrary conjunction of changes of the skin and bones we call SKIBO diseases. Some of them have a high potential for mimicking malignant bone lesions, often with the consequence of unnecessary biopsies. In this article we present the typical dermatologic and radiologic signs and symptoms of neurofibromatosis, sarcoidosis and pustulotic arteroosteitis (PAO) with special focus on such skeletal lesions that may mimic malignancy.