High haematocrit in haemodialysis patients can be controlled by theophylline administration.

Three patients on chronic maintenance haemodialysis have progressively increased their haematocrit to reach values between 40 and 45%, a situation associated with an increased risk of thrombosis of their arteriovenous fistulae. Two of them had been submitted to repeated phlebotomies, which remained unsuccessful despite the induction of a profound iron deficiency in one of them. Hence, a trial with oral theophylline was performed in the three patients, resulting in a sustained decrease of the haematocrit (from 43.6 to 33%) and endogenous erythropoietin (from 46 to 15 mU/ml) levels. In two patients, theophylline therapy was stopped transiently due to gastrointestinal side-effects, which resulted in a rapid return to previous haematocrit levels; rechallenge with a better tolerated preparation, however, was efficient again. We conclude that oral theophylline appears to be an efficient treatment to control too high haematocrit levels in dialysis patients.