[Methylguanidine kinetics during oral active vitamin D pulse therapy for secondary hyperparathyroidism]

Active vitamin D (VD) metabolite preparations have been used in the management of secondary hyperparathyroidism (2 degrees HPT) due to impaired calcium and phosphorus metabolism and can allegedly be expected to prevent, to some extent, the progression of this pathological condition. Unfortunately, however, it is not uncommon for us in routine clinical practice to find 2 degrees HPT of moderate or greater severity embarrassingly unamenable to treatment with these VD preparations in ordinary oral therapeutic doses. Recent studies have gradually reported that intravenous administration of 1,25-(OH)2D3 and oral active VD pulse therapy has been therapeutic approach to 2 degrees HPT. Methylguanidine (MG) among other GCs, its precursor is already identified as creatinine and activated oxygen as well PTH and VD are known to participate in the process leading to its formation. In the present study, we administered oral 1,25-(OH)2D3 pulse therapy to patients with chronic renal failure for the treatment of 2 degrees HPT in an attempt to assess the effectiveness of this therapeutic regimen and to explore the clinical effect of MG on responsiveness to the therapy. The purpose of this paper is to present the results thus obtained. Oral 1,25-(OH)2D3 pulse therapy (6 micrograms once a week) was administered to 21 hemodialysis patients with for 12 weeks. Of these 21, 10 patients responded to the therapy with a more than 20% reduction in serum (PTH): (responsive group), whereas the remaining 11 did not (resistant group). Pretreatment serum PTH levels were significantly higher in the latter group than the former.(ABSTRACT TRUNCATED AT 250 WORDS)