Relationship of Conjunctival and Corneal Calcification with Secondary Hyperparathyroidism in Hemodialysis Patient.

Hyperphosphatemia is the consequent of End-Stage-renal failure. Inadequate control of serum phosphorus results in elevated Ca×P product and resultant soft tissue deposition consist of conjunctival and corneal calcification. In this study we evaluated the relationship of conjunctival and corneal calcification with secondary hyperparathyroidism in hemodialysis patients. This is a descriptive – analytic study was done on 24 hemodialysis patients. We measured serum calcium, phosphorus, alkaline phosphatase, iPTH and conjunctival and corneal calcification by using slip – lamp microscope according to a modification of porters criteria. Total patients were 24. The duration of hemodialysis were 30.7 ± 21.7 months. The results of biochemical values were: Ca: 9.1 ± 0.8 mg/dl, P: 6.5 ± 2.2 mg/dl, ipTH: 488 ± 326 pg/ml, Ca×P: 51.5 ± 16.6 The mean of conjunctival and corneal calcification score was 7.1 ± 4.There were a positive correlation between conjunctival and corneal calcification with duration of hemodialysis (p=0.033, r=0.436), Ca×P product (p=0.007, r=0.538). P(p=0.006, r=548) and ipTH (p=0.028, r=0.449). There were not any correlation between conjunctival and corneal calcification with ages of the patients, serum calcium and alkalin phosphatase. Positive correlation of serum phosphorus, Ca×P product and iPTH with conjunctival and corneal calcification and no significant correlation of corneal and conjunctival calcification with serum calcium means that there is a central role for phosphorus in calcium-phosphorus deposition in soft tissues like cornea and conjunctivae, needs to further attention to phosphorus control in hemodialysis patients.