The Autohaemolysis Test: Appraisal of the Method for the Diagnosis of Pyruvate Kinase Deficiency and the Effect of pH and Additives

Summary The autohaemolysis test has been compared in its original form with a modified procedure in which the blood is mixed continuously throughout the 48‐hour period. Continuous mixing of blood from ten PK‐deficient subjects yielded values unequivocally outside the normal range. Two of these subjects gave autohaemolysis results within the normal range when tested by the original method. Glucose added to the PK‐deficient blood did not significantly reduce the autohaemolysis values by whichever method was used. Normal or PK‐deficient blood incubated at different pH values with lactic, hydrochloric and orthophosphoric acid, or in phosphate buffer, gave minimum haemolysis at pH 6.7–7.1. Adenosine triphosphate added to normal or PK‐deficient blood does not sustain glycolysis and its effectiveness in diminishing autohaemolysis is considered to be partly due to pH. Adenosine, inosine and guanosine added to normal blood maintain glycolysis, which explains their beneficial effect upon autohaemolysis.