[Resorption and tolerance of the high doses of ferrous sulfate and ferrous gluconate in the patients on peritoneal dialysis].

BACKGROUND/AIM: Iron supplementation plays a crucial role in peritoneal dialysis (PD) patients. Oral iron substitution is more convenient than intravenous therapy in PD patients, but impaired absorption and adverse effects may be limiting factors for oral treatment. The aim of this study was to compare the absorption and side effects of high doses ferrous sulphate and ferrous gluconate in PD patients. METHODS: Blood samples were taken from 29 PD patients at baseline, as well as 2, 4 and 8 hours after oral intake of 4 ferrous sulphate tablets (containing 105 mg elemental iron per tablet). The test was repeated using 8 ferrous gluconate drinkable ampoules (containing 50 mg elemental iron per ampoule). RESULTS: The maximal increase in serum iron level during the test with iron sulphate was 113.51 +/- 103.37% versus the initial values of 183.87 +/- 37.38% during the ferrous gluconate test. The maximal values of serum iron after the intake of ferrous sulphate were 26.23 +/- 9.95 micromol/l versus 30.97 +/- 8.65 micromol/l after the intake of ferrous gluconate. There was a statistically significant difference between these two groups. Six patients showed an increase in serum iron of more than 300% after a high ferrous gluconate dose, while in 15 of the patients serum iron increased between 100% and 300%, and in 8 of the patients serum iron levels increased by less than 100%. Side effects occurred more frequently after the intake of ferrous sulphate than ferrous gluconate. CONCLUSION: High doses of oral iron were well absorbed and tolerated in PD patients. Ferrous gluconate was better absorbed and tolerated than ferrous sulphate, thus we recommend it for oral iron supplementation in PD patients.

[Efficacy of bolus intravenous iron treatment in peritoneal dialysis patients].

INTRODUCTION: Normocytic, normochromic anemia is one of the first signs of chronic renal failure and it is common in patients on chronic dialysis treatment. It causes decrease in oxygen supply to tissues, increases cardiac minute volume, causes left ventricular hyperthrophy, cardiac insufficiency, disorders related to cognitive functions and immune response, and increases morbidity and mortality rates. The leading cause of anemia in patients on chronic peritoneal dialysis (PD) is iron depletion and most patients on PD need oral or parenteral iron supplementation. The aim of this study was to evaluate our first experience with bolus intravenous ferrogluconate therapy in patients on chronic peritoneal dalysis at the Nephrology Clinic of the Clinical Center of Serbia (CCS). MATERIAL AND METHODS: We examined 11 patients, 7 males and 4 females, mean-age 49 years (range 31 to 68 years) on chronic PD. All patients received blood transfusions, oral or intramuscular iron supplementation before 465 to 665 mg ferrogluconate therapy was given in 500 ml. saline intravenous infusion: 5 of them were on erythropoietin therapy and 2 of them started with EPO therapy after the ferrogluconate therapy. RESULTS: The blood count improved during the first 3 months after application of bolus intravenous iron therapy (ferrogluconate); erytrhopoietin dose was not increased during the follow-up. Some patients suffered from side effects during infusion and 6 patients received the complete treatment. DISCUSSION: Blood count improves in a number of patients affected by endstage renal desease during the first months on continuous ambulatory peritoneal dialysis (CAPD) treatment. But a large number of patients on chronic CAPD treatment are iron-depleted and they require oral or parenteral substitution. Side effects and complications of intravenous iron therapy were not severe and only one patient suffered from allergic manifestations. Ferremia and blood count improved in patients who did not receive erythropoietin during the follow-up, and patients on erythropoietin therapy required lower doses after receiving the intraveonous iron therapy. CONCLUSION: Blood count improvement and the lack of severe side effects speak in favor of further iron supplementation with bolus intravenous iron replacement.

Relative roles of endothelin-1 and angiotensin II in experimental post-ischaemic acute renal failure.

BACKGROUND: The relative roles of endothelin (ET)-1 and angiotensin (ANG) II in post-ischaemic acute renal failure (ARF) have not been fully established so far. With the aim of contributing to this goal, we assessed in this study the effect of ANG II and ET-1 blockade on the course of post-ischaemic-ARF. METHODS: Anaesthetized Wistar rats received i.v. either bosentan (a dual ET receptor antagonist; 10 mg/kg body weight) or losartan [ANG II type 1 (AT(1)) receptor antagonist; 5 or 10 mg/kg body weight] or both, 20 min before, during and 20 min after ischaemia. Rats in the control group received the vehicle via the same route. Survival and renal function were monitored up to 8 days after the ischaemic challenge, while haemodynamic parameters were measured 24 h after ARF. RESULTS: Our results demonstrate that bosentan treatment has a more beneficial effect on experimental ARF than losartan. The survival rate was remarkably higher in bosentan-treated rats than in both rat groups treated with losartan. In the ARF group treated with bosentan, renal blood flow (RBF) was increased by 129% in comparison with the untreated ARF group, whereas in the losartan-treated ARF groups, RBF was only approximately 35 or 38% higher than in control ARF rats. The glomerular filtration rate was markedly higher in bosentan-treated rats than in all other ARF groups on the first and second day after ischaemia. Tubular cell injury was less severe in bosentan-treated rats than in the control ARF rats, but in losartan-treated groups it was similar to that in the ARF group. Concurrent blockade of both ET and AT(1) receptors did not improve ARF because this treatment induced a marked decrease in blood pressure. CONCLUSIONS: These results suggest that ET-1 blockade is more efficient in improving the early course of post-ischaemic renal injury than ANG II inhibition, and that blockade of ET-1 might be effective in prophylaxis of ischaemic ARF.