Βones, stones and androgen deprivation therapy.

It is well known that patients with recurrent calcium nephrolithiasis present bone mineral density loss manifesting as osteopenia or osteoporosis in the lumbar spine and/or hip.1 Moreover, it has been observed that in patients with calcium stones and idiopathic hypercalciuria, higher levels of fasting calcium/creatinine increase the possibility of osteopenia, therefore there is a risk factor for bone mineral density loss.2 Some markers that are increased in patients with bone mineral density loss and recurrent calcium nephrolithiasis, such as alkaline phosphatase, osteocalcine, β-crosslaps, calciuria and fasting calcium/creatinine in urine, are useful in the diagnosis, together with image tests (bone densitometry, abdominal CT) and follow-up after initiation of treatment.2 Although no single mechanism has as yet been identified to explain bone mineral density in patients with recurrent calcium stones, inflammatory and hormonal factors could be involved in the pathophysiology.3