Acute haemolytic crisis in a Thai patient with homozygous haemoglobin Constant Spring (Hb CS/CS): a case report

Abstract

Acute haemolysis associated with mild upper respiratory tract infection was observed in a Thai boy who presented with a rapid decline in haemoglobin (Hb) levels, haemoglobinuria and evidence of intravascular haemolysis. Several possible causes giving rise to such a condition were excluded including G6PD deficiency, which is extremely common in Thailand. Subsequent haematological and molecular analyses demonstrated that the patient was homozygous for Hb Constant Spring (Hb CS/CS), an a globin haemoglobinopathy. It has been shown previously that patients with homozygous Hb CS had mild haemolytic anaemia secondary to an accumulation of alpha(CS) chains, which are toxic to red blood cell membrane cytoskeletons. Increased body temperature might induce more precipitation of this a globin variant. This report highlights the importance of Hb CS/CS as a potential predisposing cause of acute haemolysis in children that might be aggravated by acute bacterial or viral infections. This is particularly relevant for patients of Southeast Asian descent where this abnormal haemoglobin is highly prevalent.

Thalassemia and hemoglobinopathies in an ethnic minority group in Central Vietnam: implications to health burden and relationship between two ethnic minority groups

“…As for this study, a community-based survey conducted previously in the Co-Tu minority disclosed the markedly high frequency of Hb CS of 25%, and the apparently healthy individuals with Hb CS homozygotes were observed (Nguyen et al 2014). Inconsistent with our findings, hospital-based studies reported clinical manifestations of hemolytic anemia among homozygous Hb CS patients (Schrier et al 1997;Noguera et al 2000;Viprakasit et al 2004). Combining these contradictory findings together, it is likely that there might be some other factors responsible for the varying severities of the disease.…”

Variable Clinical Phenotypes of α-Thalassemia Syndromes

“…Hb H-Constant Spring is a common nondeletional α-thalassemia resulting from the combination of α 0 and a Constant Spring (CS) structural mutation on one α gene of the other chromosome (--/-α cs ). The homozygote state of Hb H-CS generally presents as milder anemia; however, reports of a more severe hemolysis and a potential predisposing cause for acute hemolysis were described as well as a case of severe fetal anemia with hydropic features [38,39]. It is difficult to detect the Hb H-CS on electrophoresis because of the very low Hb H-CS levels, and the reduced and unstable amounts of αCS mRNA [40].…”

Fetal anaemia from red blood cell membrane defect and co-inherited haemoglobin Constant Spring

“…Compound heterozygosity of Hb Constant Spring and α 0 -thalassaemia result in thalassaemia-intermedia phenotype. Homozygous Hb Constant Spring usually presents with mild anaemia, although acute episodic haemolysis8 and anaemic hydrops fetalis have been reported 9…”