Erythrocyte pyruvate kinase deficiency among anemic individuals in Bandar Abbas, Iran

Introduction: In addition to G6PD deficiency, human erythrocyte pyruvate
kinase (PK-R) deficiency is one of the most common causes of non-spherocytic
hemolytic anemia. Clinical severity of this disorder is not the same in
homozygote form of this disease and ranges from mild to chronic and anemia; so
it has a wide variation. Severely effected individuals require blood transfusions or
splenectomy.
Methods: In this experimental study, a complete blood count (CBC) was
performed on 2300 individuals aged 15-30 years from Bandar Abbas in
Hormozgan province, to determine the possible hemolytic anemia. From this
cohort 800 non-related individuals who had hemoglobin levels below 11.5 g/dl
were selected for further investigation and measured erythrocyte PK activity.
Results: The enzyme activity levels expected in normal population had a range of
2.2-9.7 U/gmHb while in the anemic group; the range was 0.1-11.7 U/gmHb. In
123 cases (15%) among the anemic group, 20% to 40% of the normal enzyme
activity was measured when compared with the values expected in heterogenous
individuals. Only three individuals (0.3%) in this group had below 20% of
normal enzyme activity.
Conclusion: The study revealed that the estimated gene frequency of PK
deficiency in this area is about 36 in 1000 population and the observed carrier
frequency is about 5%. If we can identify the couples who are at risk of PK
deficiency, it may be possible to reduce the burden of chronic anemia caused by
PK deficiency.