On March 31, 2020, Guo Guo (pseudonym), the youngest child with severe aplastic anemia (SAA) among five provinces in northwestern China, was discharged from germ-free transplantation room after successfully undergoing haplotype hematopoietic stem cell transplantation from his father in the First Affiliated Hospital of Xi 'an Jiaotong University (XJTU).

In November 2019, Guo Guo, a 2-year and 7-month-old boy, was diagnosed with SAA. His parents brought Guo Guo to Department of Hematology of the First Affiliated Hospital of XJTU to seek treatment. Guo Guo is the only child in the family and no HLA-matched blood donor can be identified. It is huge challenge to perform haplotype hematopoietic stem cell transplantation in a SAA child at such a young age. No hands-on experience in the transplantation regime, drug dosage, nursing and life care in the germ-free transplantation room can be obtained from most domestic transplantation centers. He Pengcheng, Director of Department of Hematology of our hospital, who previously worked in the field of pediatrics, accumulated abundant experience in the diagnosis and treatment of pediatric hematological diseases and haplotype hematopoietic stem cell transplantation. He led a team to perform haplotype hematopoietic stem cell transplantation for Guo Guo in the germ-free operation room on March 3.

The dosage requirement for children is highly demanding and the disease condition can change rapidly. Director He led all team members to conduct intimate disease observation and careful dose adjustment every day to ensure the precise treatment. Guo Guo is too young to take care of himself. Hence, female physicians and nurses became his temporary mothers. Guo Guo was gradually willing to cooperate with the treatment after attentive care.

From March 9 to 10, the bone marrow and peripheral blood hematopoietic stem cells were sampled from his father, and successively transplanted into Guo Guo. After 4 weeks, the transplantation surgery was successful and the blood cell count was restored to normal range. On March 31, the hematopoiesis was completely restored and Guo Guo was successfully discharged from the germ-free transplantation room.

This is the first case of successful haplotype hematopoietic stem cell transplantation for a SAA child at such a young age in northwest China.