<prompt> Brown tumors, compression syndromes and erythropoietin resistance is seen in:HypothyroidismHyperthyroidismHyperparathyroidismOsteoporosis  <response>: Clinical manifestations of severe hyperparathyroidism include bone pain and fragility, brown tumors, compression syndromes and erythropoietin resistance in part related to the bone marrow fibrosis. 