Prolonged breastfeeding was significantly associated with low BMD in the lumbar spine and higher prevalence of osteoporosis. However, the number of deliveries or age at the time of childbirth did not influence BMD.

Accumulating evidence shows that high sodium chloride intake increases urinary calcium excretion and may be a risk factor for osteoporosis. However, the effect of oral sodium chloride intake on bone mineral density (BMD) and risk of osteoporosis has been inadequately researched. The aim of the present study was to determine whether urinary sodium excretion (reflecting oral sodium chloride intake) associates with BMD and prevalence of osteoporosis in postmenopausal women. This cross-sectional study involved a nationally representative sample consisting of 2,779 postmenopausal women who participated in the Korea National Health and Nutritional Examination Surveys in 2008-2011. The association of urinary sodium/creatinine ratio with BMD and other osteoporosis risk factors was assessed. In addition, the prevalence of osteoporosis was assessed in four groups with different urinary sodium/creatinine ratios. Participants with osteoporosis had significantly higher urinary sodium/creatinine ratios than the participants without osteoporosis. After adjusting for multiple confounding factors, urinary sodium/creatinine ratio correlated inversely with lumbar spine BMD (P = 0.001). Similarly, when participants were divided into quartile groups according to urinary sodium/creatinine ratio, the average BMD dropped as the urinary sodium/creatinine ratio increased. Multiple logistic regression analysis revealed that compared to quartile 1, quartile 4 had a significantly increased prevalence of lumbar spine osteoporosis (odds ratios 1.346, P for trend = 0.044). High urinary sodium excretion was significantly associated with low BMD and high prevalence of osteoporosis in lumbar spine. These results suggest that high sodium chloride intake decreases lumbar spine BMD and increases the risk of osteoporosis in postmenopausal women.

A 38-year-old man, who underwent a second kidney transplantation (KT), was admitted because of antibody-mediated rejection (AMR) complicated by BK virus-associated nephropathy (BKVAN). He was placed on hemodialysis at the age of 24 years because of membranoproliferative glomerulonephritis. At the age of 28 years, he underwent a living donor KT from his father; however, 1 year after the transplantation, he developed a recurrence of the primary glomerular disease, resulting in graft failure 2 years after the first KT. Ten years later, he received a deceased-donor kidney with a B-cell-positive-cross-match. He received 600 mg of rituximab before the KT with three cycles of plasmapheresis and immunoglobulin (0.5 g/kg) therapy after KT. During the follow-up, the first and second allograft biopsies at 4 and 10 months after KT revealed AMR with a recurrence of primary glomerular disease that was reclassified as C3 glomerulonephritis (C3GN). He received a steroid pulse, rituximab, plasmapheresis, and immunoglobulin therapies. The third allograft biopsy demonstrated that the BKVAN was complicated with AMR and C3GN. As the azotemia did not improve after repeated conventional therapies for AMR, one cycle of bortezomib (1.3 mg/m 2 ×4 doses) was administered. The allograft function stabilized, and BK viremia became undetectable after 6 months. The present case suggests that bortezomib therapy may be applicable to patients with refractory AMR, even in cases complicated with BKVAN.

Diagnosing hypercalcemia is often challenging because a wide spectrum of diseases-such as malignancy, granulomatous disease, and primary hyperparathyroidism-should be considered. Sarcoidosis is a rare cause of hypercalcemia. The case of a 77-year-old male presenting with sarcoidosis-associated hypercalcemia whose serum 1,25(OH)2D level was normal is reported here. Despite a normal 1,25(OH) 2 D level and minimally enlarged hilar lymphadenopathy, the serum angiotensin-converting enzyme (ACE) level was increased. Mediastinoscopic biopsy of the right lower paratracheal lymph node revealed pathological findings compatible with sarcoidosis. Treatment with 30 mg/day oral prednisone was started. Currently, the patient is being treated with a tapered dose of oral prednisone and small doses of vitamin D and calcium. Despite its low incidence, sarcoidosis should be considered a cause of hypercalcemia. The important diagnostic factors are not only serum calcitriol levels but also serum ACE levels and pathological findings.

Adenocorticotropic hormone-independent macronodular adrenal hyperplasia (AIMAH) is a rare cause of Cushing's syndrome. It is characterized by multinodular enlargement of the adrenal glands and hypercortisolism. Although bilateral adrenalectomy is the standard therapy, unilateral adrenalectomy is an effective alternative. Here we present a case of a 71-year-old female referred to the Endocrinology Department for further evaluation of bilateral adrenal macronodular hyperplasia. Based on dynamic hormone tests and imaging studies, she was diagnosed with AIMAH. Due to persistent hypercortisolism, she underwent completion contralateral surgery after unilateral adrenalectomy. This case demonstrates that unilateral adrenalectomy should be considered in a patient presenting with obvious symptoms of hypercotisolism and relatively asymmetric adrenal enlargement.