title: Influence of renal function on clinico-pathological features of primary hyperparathyroidism.
abstract: OBJECTIVE
  Disturbed renal function may play an important role in the clinico-pathological presentation of primary hyperparathyroidism (pHPT). We studied the influence of renal function on the clinico-pathological characteristics of 141 patients (123 women and 18 men) with surgically proven pHPT.
  
  
  METHODS
  The 141 patients were assigned to one of two groups based on creatinine clearance (C(cr)) level: a renal insufficiency group (n=37) in which C(cr) of patients was <70 ml/min and a normal renal function group (n=104) in which C(cr) was > or =70 ml/min. Clinical presentation and biochemical indices were evaluated and compared between the two groups.
  
  
  RESULTS
  Age, and frequency of hypertension and of diabetes mellitus were significantly (P<0.001, P<0.05 and P<0.05 respectively) higher in the renal insufficiency group than in the normal renal function group. Serum levels of calcium, intact parathyroid hormone and bone Gla protein were significantly (P<0.05) higher and the excised parathyroid weighed significantly more (P<0.05) in the renal insufficiency group than in the normal renal function group; however, serum 1,25-dihydroxyvitamin D (1,25(OH)(2)D) and 24 h urinary calcium excretion were significantly (P<0.001 and P<0.05 respectively) lower in the former than in the latter group. There was a significant inverse correlation between C(cr) level and serum calcium (r=0.315, P<0.001) and a significant positive correlation between C(cr) level, 1,25(OH)(2)D (r=0.315, P<0.001), and 24 h calcium excretion (r=0.458, P<0.0001).
  
  
  CONCLUSIONS
  Clinico-pathological features of pHPT were notably influenced by even moderate renal insufficiency. Urinary calcium excretion decreased according to the decrease in glomerular filtration rate. Therefore, endocrinologists need to appraise urinary calcium excretion and renal function of pHPT patients when considering surgery or in discriminating familial hypocalciuric hypercalcemia.
authors.affiliation: Noguchi Thyroid Clinic and Hospital Foundation, 6-33 Noguchi-Nakamachi, Beppu Oita 874-0932, Japan. yama@noguchi-med.or.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamashita
authors.forename: Shiro
authors.initials: S
authors.lastname: Noguchi
authors.forename: Shinya
authors.initials: S
authors.lastname: Uchino
authors.forename: Shin
authors.initials: S
authors.lastname: Watanabe
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Murakami
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ogawa
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Masatsugu
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takamatsu
authors.forename: Eiji
authors.initials: E
authors.lastname: Miyatake
authors.forename: Hiroto
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D000368:Aged; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood / Q000652:urine; D003404:Creatinine / Q000097:blood; D003928:Diabetic Nephropathies / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000473:pathology* / Q000503:physiopathology*; D007668:Kidney / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000473:pathology; D051437:Renal Insufficiency / Q000473:pathology / Q000503:physiopathology
chemical_list: D003404:Creatinine; D002117:Calcitriol; D002118:Calcium