Fanconi anemia is an autosomal recessive genetic disorder characterized by pancytopenia with congenital malformations. Its pathogenesis may be related to defects in DNA repair mechanisms.

bubble_chart Clinical Manifestations

1. General manifestations of anemia, bleeding tendency, and susceptibility to infections. Skin pigmentation or patchy brown spots are commonly observed, and physical and intellectual development may be delayed. There is no hepatosplenomegaly or lymphadenopathy.
2. Congenital malformations often include skeletal deformities, such as absence or malformation of the thumb, hypoplasia of the first metacarpal bone, ulnar deformities, toe deformities, microcephaly, etc. Renal malformations, eye, ear, and genital deformities, as well as congenital heart disease, may also occur.

bubble_chart Auxiliary Examination

1. Blood Picture The typical manifestation is pancytopenia. Thrombocytopenia often occurs first, gradually progressing to pancytopenia. A few cases may present with only one or two cell line reductions. Anemia may be macrocytic. Reticulocyte count is decreased. Toxic granules may be observed in granulocytes.
2. Bone Marrow Findings Similar to aplastic anemia. Focal hyperplasia may occur, and megaloblastoid erythroblasts may appear. In vitro bone marrow stem cell culture shows reduced granulocyte and erythrocyte colony formation.
3. Generation and Transformation Changes Approximately half of the affected children develop aminoaciduria (mostly prolinuria), increased fetal hemoglobin (5-15%). Red blood cells persistently exhibit i antigen (normally disappears before 2 years of age).
4. Chromosomal Abnormalities Chromosome analysis of peripheral blood lymphocyte cultures may reveal aberrations such as breaks, chromatid exchanges, and ring chromosomes. Reduced sister chromatid exchange is more diagnostically significant.

bubble_chart Diagnosis

(1) Age of onset: The disease often occurs in childhood. Boys are more likely to develop the condition between the ages of 4 and 7, while girls are more commonly affected between 6 and 10 years old. (2) Family history: Approximately 10-30% of parents are consanguineous marriages.

bubble_chart Treatment Measures

﹝Treatment﹞

(1) General supportive therapy: Same as for aplastic anemia. Blood transfusion should be given when anemia is severe. (2) Hormone therapy: Administration of one androgen and one corticosteroid is effective in most cases. Commonly used are oxymetholone [up to 5mg/(kg·d)] plus a smaller dose of prednisone [1mg/(kg·d)]. A significant hematopoietic response is generally observed 2–4 months after medication. The dosage should be gradually reduced once hemoglobin levels normalize, with a maintenance dose used to keep hemoglobin at the lower limit of normal. During treatment, attention should be paid to side effects such as liver function impairment. (3) Bone marrow transplantation may be performed if conditions permit.

bubble_chart Prognosis

Before androgen therapy, once anemia occurs, the 5-year survival rate is approximately 50%. After hormone treatment, the survival rate significantly improves, but 5–10% of cases develop acute granulocytic leukemia or other malignant tumors.