Hemoglobin Constant Spring

Very rare: more common in the Thai population and in the Mekong delta where 1 to 8 % of the population is affected. Recessive autosomal transmission of a mutation of the HBA2 gene (11p15.4) causes an lenghtening of the alpha chain. Heterozygous patients are generally asymptomatic and homozygous adults have moderate hemolytic anemia.


In the neonatal and infant periods, the homozygous form may present as a

-        fetal anemia with hydrops fetalis,

-        moderate hemolytic microcytic normochromic anemia

-        sometimes delayed jaundice.


Some cases of acute hemolysis in cases of viral or bacterial infection have been described.


Anesthetic implications: 

check hemoglobin level


References :

-        Komvilaisak P, Jetsrisuparb A, Fucharoen G et al.
Clinical course of homozygous hemoglobin Constant Spring in pediatric patients.
J Pediatr Hematol Oncol 2018; 40: 409-12


Updated: January 2020