Spondyloarthropathy occurring in long-standing idiopathic hypoparathyroidism.

Idiopathic hypoparathyroidism can rarely present with extensive spondyloarthropathic changes that closely resemble ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis, or fluorosis. Clinical presentation of the patient, typical laboratory parameters, and radiological findings aid in their differential diagnosis. Extensive spondyloarthropathy with normal sacroiliac joints in patients with neuromuscular symptoms like tetany, paresthesia, and hypocalcemia should raise the possibility of this entity.