Category: Calcium/Bone Disorders
Metabolic derangements are part of the hallmark findings in patients with sarcoidosis. It is usually associated with suppressed parathyroid hormone (PTH), elevated calcium and elevated vitamin D levels. We present a rare case of initial laboratory findings of low vitamin D, normal calcium and elevated PTH.
A 27-year-old woman with a history of 25-hydroxy vitamin D deficiency (19ng/ml; N: ≥ 30ng/ml) was referred for further management. Preliminary work-up revealed elevated PTH- 73pg/ml (N: 14-64pg/ml) and normal corrected calcium- 9.4mg/dl (N: 8.6-10.3mg/dl). She was commenced on Ergocalciferol. Laboratory findings on subsequent visit however revealed a 25-hydroxy vitamin D level of 19.8ng/ml, suppressed PTH of 5pg/ml and elevated corrected calcium of 11.1mg/dl. At this point, patient also complained of skin rashes and was referred for a biopsy. Further work-up revealed an elevated angiotensin-converting enzyme level- 110μl (N: 14-82μl), elevated 1,25-hydroxy vitamin D level- 279.6pg/ml (N: 19.9-79.3pg/ml). Ergocalciferol dose was reduced. Skin biopsy revealed granuloma dermatitis consistent with granuloma annulare. Chest X-ray and CT scan of the chest were unremarkable. Patient was commenced on prednisone and received several intermittent treatments in the course of six months until her corrected calcium normalized (9.5mg/dl), as well as her PTH (36pg/ml) and 1,25-hydroxy vitamin D level (83.1ng/ml).
Results : N/A
Due to 1 alpha-hydroxylase produced by the granuloma in Sarcoidosis, elevated calcium, suppressed PTH and elevated 1,25- hydroxy vitamin D levels have long been associated with the disease. Research has also shown that some patients might have low 25-hydroxy vitamin D levels especially at the onset of the disease. However, not much is known about how metabolic and laboratory findings may differ between patients with pulmonary sarcoidosis compared with those with extra-pulmonary sarcoidosis throughout the progression of the disease. This is especially pertinent in patients such as in the index case who presented with low 25-hydroxy vitamin D, normal calcium and elevated PTH and then continued to have low 25-hydroxy vitamin D with normalized PTH. More research is required to elucidate this and our patient remains under close clinical monitoring.
It is plausible that the pattern of findings in extra-pulmonary sarcoidosis may vary from that of pulmonary sarcoidosis. It is also possible that laboratory findings may differ depending on the course and progression of the disease. To the best of the authors’ knowledge, this is the only report in literature documenting these atypical findings in non-pulmonary sarcoidosis.
University of Texas RGV-DHR
Fatimah Bello is a 2nd year Internal Medicine Resident and is interested in pursuing an Endocrinology fellowship.