Germ Cell Dysfunction is Universal in Adolescent Male Patients with β-thalassemia Following Earlier Successful Hematopoietic Stem Cell Transplantation

Objective: To assess gonadal function in adolescent male patients with β-thalassemia who underwent earlier successful hematopoietic stem cell transplantation (HSCT). Methods: Fifty-two male patients with β-thalassemia, aged ≥10 years, who had undergone HSCT ≥2 years previously were included. Clinical data, such as age, genital Tanner (GT) stage at HSCT and enrollment, and serum ferritin levels, were collected. Gonadal function was evaluated through measurements of serum luteinizing hormone, follicle-stimulating hormone (FSH), testosterone, inhibin B levels, and semen analysis. Results: Age at enrollment and HSCT were 17 (10-31) and 9 (1-19) years, respectively. The duration from HSCT to enrollment was 7.5 (2-20) years. Of 52 patients, 46 (88%) exhibited Sertoli cell dysfunction. Thirty-one patients had relatively small testes for their GT stage, 34 of 44 with GT V had elevated FSH of ≥5 IU/L, and 20 of 49 with GT stages 2-5 had low serum inhibin B levels. None of the patients with GT stage 5 showed Leydig cell dysfunction or gonadotropin deficiency. Serum FSH ≥8 IU/L showed the best diagnostic accuracy for detecting oligo- and azoo-spermia. All 39 patients who underwent semen analysis had >1 abnormal parameters. Having relatively small testes for GT stage and serum FSH ≥8 IU/L were associated with oligospermia or azoospermia (p<0.01). Conclusion: Male patients with β-thalassemia after HSCT experienced universal impaired spermatogenesis and frequent Sertoli cell dysfunction but their Leydig cell function appeared to be preserved. Male patients and/or their guardians should be informed of the high likelihood of future subfertility before HSCT.