title: The effect of hypercalcemia on allograft calcification after kidney transplantation.
abstract: OBJECTIVE
  Persistent hypercalcemia after kidney transplantation (KTx) may cause nephrocalcinosis and graft dysfunction. The aim of this study was to evaluate patients with hypercalcemia and assess its effect on tubulointerstitial calcification.
  
  
  METHODS
  A total of 247 recipients were enrolled. Transient and persistent hypercalcemia was defined as hypercalcemia (corrected serum calcium >10.2 mg/dL) persisting for 6 and 12 months after KTx, respectively. The severity of calcification in the 0-h, 6- and 12-month protocol biopsies of patients with transient (n = 8) and persistent hypercalcemia (n = 20) was compared with a matched control group (n = 28).
  
  
  RESULTS
  Twenty-eight patients were hypercalcemic at 6 months posttransplantation. Serum calcium levels were normalized in eight of them at the end of the first year. Dialysis duration was a positive predictor of persistent hypercalcemia. Tubulointerstitial calcification was detected in 70.6 and 90 % of patients with persistent hypercalcemia at 6 and 12 months posttransplantation, respectively. In 20 % of patients with transient hypercalcemia, severity of calcification regressed at 12 months posttransplantation along with normalization of serum calcium levels. Graft functions and histopathological findings (ci, ct, ci + ct, cv, ah, percentage of sclerotic glomeruli) were not different at 6 and 12 months posttransplantation.
  
  
  CONCLUSIONS
  Hypercalcemia and persistent hyperparathyroidism are not rare after KTx. Tubulointerstitial calcification is more common and progressive among patients with persistent hypercalcemia. Normalization of calcium levels may contribute to regression of calcification in some patients.
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Aygül
authors: A
authors: Çeltik
authors: Department of Pathology, School of Medicine, Ege University, Bornova, Izmir, 35100, Turkey.
authors: Sait
authors: S
authors: Şen
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Mümtaz
authors: M
authors: Yılmaz
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Meltem Seziş
authors: MS
authors: Demirci
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Gülay
authors: G
authors: Aşçı
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Abdülkerim Furkan
authors: AF
authors: Tamer
authors: Department of Pathology, School of Medicine, Ege University, Bornova, Izmir, 35100, Turkey.
authors: Banu
authors: B
authors: Sarsık
authors: Department of General Surgery, School of Medicine, Ege University, Bornova, Izmir, 35100, Turkey.
authors: Cüneyt
authors: C
authors: Hoşcoşkun
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey. huseyin.toz@ege.edu.tr.
authors: Hüseyin
authors: H
authors: Töz
authors: Division of Nephrology, Department of Internal Medicine, School of Medicine, Ege University, 35100, Bornova, Izmir, Turkey.
authors: Ercan
authors: E
authors: Ok
mesh_terms: D000328:Adult; D064591:Allografts / Q000473:pathology* / Q000503:physiopathology; D002118:Calcium / Q000097:blood; D016022:Case-Control Studies; D002908:Chronic Disease; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000097:blood / Q000150:complications*; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009397:Nephrocalcinosis / Q000209:etiology* / Q000473:pathology; D011184:Postoperative Period
chemical_list: D002118:Calcium
keywords: Graft dysfunction; Hypercalcemia; Hyperparathyroidism; Kidney transplantation; Microcalcification; Protocol biopsy