A bone biopsy specimen in a long-term
hemodialysis patient with
sarcoidosis coexisting with severe
hypoparathyroidism has demonstrated that a persistent near physiological level of
1,25-dihydroxyvitamin D3 contributes to the preservation of bone remodeling and has the potential to retard the development of
vascular calcification and
atherosclerosis.
Sarcoidosis-related
hypercalcemia and
hypoparathyroidism, which is characterized by
1,25-dihydroxyvitamin D3 (
1,25(OH)2D3) overproduction, is rarely seen in
hemodialysis patients. Herein, we describe a 60-year-old Japanese woman on
hemodialysis for 35 years who presented with malaise and
hypercalcemia. Severe
hypoparathyroidism without
parathyroidectomy and a preserved
1,25(OH)2D3 level were detected. Computed tomography showed bilateral axillary
lymphadenopathy and minimal aortic and soft tissue calcification. The axillary node biopsy led to a definite diagnosis of
sarcoidosis. A bone biopsy specimen obtained from the right iliac crest showed remodeling of normal lamellar bone with scalloped cement lines and clear double labeling by
tetracycline on fluorescence microscopy. Histomorphometric analysis revealed that the bone formation rate was preserved (30.0 %/year), together with a decrease of osteoid volume (5.75 %) and fibrous volume (0 %), indicating that the patient did not have adynamic
bone disease and only showed mild disease. This is the first documented case of
sarcoidosis-related
hypercalcemia associated with severe
hypoparathyroidism in a long-term
hemodialysis patient who underwent bone histomorphometry. Our findings suggest that, in
hemodialysis patients with
sarcoidosis coexisting with severe
hypoparathyroidism, a persistent near physiological level of
1,25(OH)2D3 contributes to the preservation of bone remodeling and has the potential to retard the development of
vascular calcification and
atherosclerosis.