TCH-022 Intradialytic Calciphylaxis in Renal Patients. Development of an Injectable Solution of 25% Sodium Thiosulfate For Treatment

Abstract

Background Calciphylaxis (calcific uremic arteriolopathy) is the ischemic ulceration of the skin caused by the disseminated calcification of the subcutaneous tissue and small arteries as a consequence of hyperparathyroidism in uremic patients. Purpose To describe the method of preparation and checking of an injectable solution of 25% sodium thiosulfate for the treatment of intradialytic calciphylaxis in renal patients. Materials and MethodsSodium thiosulfate is an antioxidant, vasodilator and calcium chelator. The preparation process for the solution of 25% sodium thiosulfate is: Ingredients: Sodium thiosulfate pentahydrate: 25 g, water for injection (WFI): qs 100 ml. Preparation: Weigh the amount of sodium thiosulfate in a sterile beaker. Then, working in a horizontal laminar flow hood, boil WFI to eliminate CO2. Dissolve the thiosulfate in about 80 ml of boiled water. Check that the pH of the solution is between 6 and 9.5, if it is not, adjust with HCl or NaOH. Flush into a 100 ml volumetric flask and make up to volume. Filter with a double 0.22 micron philtre. Finally pack with 50 ml syringe into a sterile glass bottle and label. Results The result is a solution of 100 ml of 25% sodium thiosulfate, transparent, sterile and stable for 30 days in refrigerator. For QC a visual particulate sterility cheque is performed by sowing in aerobic and anaerobic cultures and a bubble point test to verify the integrity of the philtres. Conclusions Proper preparation and checking of the 25% solution of sodium thiosulfate has guaranteed its parenteral administration is safe. The treatment is effective and well tolerated, helping patients and improving their quality of life. No conflict of interest.