Komvilaisak Patcharee, Jetsrisuparb Arunee, Fucharoen Goonnapa, Komwilaisak Ratana, Jirapradittha Junya, Kiatchoosakun Pakaphan
Departments of Pediatrics.
Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
J Pediatr Hematol Oncol. 2018 Jul;40(5):409-412. doi: 10.1097/MPH.0000000000001160.
Hemoglobin (Hb) Constant Spring is an alpha-globin gene variant due to a mutation of the stop codon resulting in the elongation of the encoded polypeptide from 141 to 172 amino acid residues. Patients with homozygous Hb Constant Spring are usually mildly anemic.
We retrospectively describe clinical manifestations, diagnosis, laboratory investigations, treatment, and associated findings in pediatric patients with homozygous Hb Constant Spring followed-up at Srinagarind Hospital.
Sixteen pediatric cases (5 males and 11 females) were diagnosed in utero (N=6) or postnatal (n=10). Eleven cases were diagnosed with homozygous Hb Constant Spring, 4 with homozygous Hb Constant Spring with heterozygous Hb E, and 1 with homozygous Hb Constant Spring with homozygous Hb E. Three cases were delivered preterm. Six patients had low birth weights. Clinical manifestations included fetal anemia in 6 cases, hepatomegaly in 1 case, hepatosplenomegaly in 2 cases, splenomegaly in 1 case. Twelve cases exhibited early neonatal jaundice, 9 of which required phototherapy. Six cases received red cell transfusions; 1 (3), >1 (3). After the first few months of life, almost all patients had mild microcytic hypochromic anemia and an increased reticulocyte count with a wide red cell distribution (RDW), but no longer required red cell transfusion. At 1 to 2 years of age, some patients still had mild microcytic hypochromic anemia and some had normocytic hypochromic anemia with Hb around 10 g/dL, increased reticulocyte count and wide RDW. Associated findings included hypothyroidism (2), congenital heart diseases (4), genitourinary abnormalities (3), gastrointestinal abnormalities (2), and developmental delay (1).
Pediatric patients with homozygous Hb Constant Spring developed severe anemia in utero and up to the age of 2 to 3 months postnatal, requiring blood transfusions. Subsequently, their anemia was mild with no evidence of hepatosplenomegaly. Their Hb level was above 9 g/dL with hypochromic microcytic blood pictures as well as wide RDW. Blood transfusions have not been necessary since then.
血红蛋白（Hb）恒春型是一种α-珠蛋白基因变异体，由终止密码子突变导致编码的多肽从141个氨基酸残基延长至172个氨基酸残基。纯合子Hb恒春型患者通常有轻度贫血。
我们回顾性描述了在诗里拉吉医院随访的纯合子Hb恒春型儿科患者的临床表现、诊断、实验室检查、治疗及相关发现。
16例儿科病例（5例男性和11例女性）在宫内（n = 6）或出生后（n = 10）被诊断。11例被诊断为纯合子Hb恒春型，4例为纯合子Hb恒春型合并杂合子Hb E，1例为纯合子Hb恒春型合并纯合子Hb E。3例早产。6例出生体重低。临床表现包括6例胎儿贫血，1例肝肿大，2例肝脾肿大，1例脾肿大。12例出现早期新生儿黄疸，其中9例需要光疗。6例接受了红细胞输血；1例（3次），>1例（3次）。在生命的最初几个月后，几乎所有患者都有轻度小细胞低色素性贫血，网织红细胞计数增加，红细胞分布宽度（RDW）增宽，但不再需要红细胞输血。在1至2岁时，一些患者仍有轻度小细胞低色素性贫血，一些患者有正细胞低色素性贫血，血红蛋白约为10g/dL，网织红细胞计数增加，RDW增宽。相关发现包括甲状腺功能减退（2例）、先天性心脏病（4例）、泌尿生殖系统异常（3例）、胃肠道异常（2例）和发育迟缓（1例）。
纯合子Hb恒春型儿科患者在宫内及出生后2至3个月内发生严重贫血，需要输血。随后，他们的贫血较轻，无肝脾肿大证据。他们的血红蛋白水平高于9g/dL，有低色素小细胞血象以及增宽的RDW。此后不再需要输血。
