title: Osteoporosis and osteopathy markers in patients with mastocytosis.
abstract: OBJECTIVE
  Osteoporosis, osteosclerosis, and lytic bone lesions have been observed in patients with systemic mastocytosis (SM). We examined bone mineral density (BMD) biochemical turnover markers and serum tryptase levels in SM, which is considered a rare disease.
  
  
  METHODS
  Seventeen adult patients (5 females, 12 males; median age: 33 years, range: 20-64) with mastocytosis were included in this study. We investigated the value of quantitative ultrasound (QUS) of the calcaneus in the assessment of BMD in SM patients, as well as BMD of the lumbar spine (L1-L4), femoral neck, and distal radius using dual energy x-ray absorptiometry (DXA) and plasma tryptase levels, biochemical markers of bone turnover.
  
  
  RESULTS
  At lumbar spine L1-L4, the femoral neck, and the distal radius or as calcaneus stiffness, 12 of 17 patients had T-scores of less than -1 at least at 1 site, reflecting osteopenia. Three of 17 patients had T-scores showing osteoporosis (T-score <-2.5). There was no relationship between DXA and bone lesion severity. We also found a significant positive correlation between tryptase levels and disease severity, as well as between disease severity and pyridinoline (p<0.01 by Spearman's test).
  
  
  CONCLUSIONS
  DXA and calcaneal QUS may not be appropriate techniques to assess bone involvement in SM patients because of the effects of osteosclerosis. This study further shows that the osteoclastic marker pyridinoline is helpful in patients with severe disease activity and sclerotic bone lesions to show bone demineralization.
authors: İstanbul University İstanbul Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, İstanbul, Turkey. E-mail: nalpay@istanbul.edu.tr.
authors: Nilüfer
authors: N
authors: Alpay Kanıtez
authors: Burak
authors: B
authors: Erer
authors: Öner
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authors: Doğan
authors: Nesimi
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authors: Büyükbabani
authors: Can
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authors: Baykal
authors: Dilşad
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authors: Sindel
authors: Refik
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authors: Tanakol
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