Serum trypsin-like immunoreactivity and secondary hyperparathyroidism in renal failure.

In 46 kidney patients aged from 30 to 71 years, after an overnight fast, serum levels of trypsin (TLI), gastrin (Gas), parathromone (PTH), calcium (Ca), magnesium (Mg), phosphate (iP), amylase, were evaluated. Ten patients had a normal renal function; in 18 patients glomerular filtration rate (GFR) ranged from 5 to 70 ml/m'; 18 patients with GFR below 2 ml/m' were treated with 4 hours hemodialysis. In dialysed patients TLI was evaluated before and after dialysis. In patients with FGR ranging from 120 to 5 ml/m' a significant inverse correlation (p <0.001) appeared between TLI and GFR values. In the same group a significant direct correlation (p <0.001) was found between PTH and TLI. The study showed also a significant direct correlation between amylase and TLI (p <0.001); likewise TLI, amylase was inversely correlated to GFR (p <0.01) and directly to PTH (p <0.001). No correlation was found between TLI and Gas, Ca, Mg, iP. A significant inverse correlation was found between PTH and GFR (p <0.01). Because serum level of PTH, amylase and TLI were related to GFR values, we calculated partial correlation between these parameters. The partial correlation coefficients of the relation between PTH and TLI, PTH amylase, holding GFR constant, were higly significant (p <0.001). On the contrary, holding a constant PTH, the correlations between pancreatic enzymes and GFR were not confirmed. Pre-dialysis TLI levels were significantly higher than post-dialysis (p <0.05). In conclusion: 1) TLI and amylase have the same behaviour in renal failure; 2) the levels of both enzymes are high in renal insufficiency; their values seem to be correlated to secondary byperparathyroidism.