People with more severe haemophilia experience more severe and more frequent bleeds, while people with mild haemophilia usually experience more minor symptoms except after surgery or serious trauma. In cases of moderate haemophilia symptoms are variable which manifest along a spectrum between severe and mild forms.In both haemophilia A and B, there is spontaneous bleeding but a normal bleeding time, normal prothrombin time, normal thrombin time, but prolonged partial thromboplastin time. Internal bleeding is common in people with severe haemophilia and some individuals with moderate haemophilia. The most characteristic type of internal bleed is a joint bleed where blood enters into the joint spaces. This is most common with severe haemophiliacs and can occur spontaneously (without evident trauma). If not treated promptly, joint bleeds can lead to permanent joint damage and disfigurement. Bleeding into soft tissues such as muscles and subcutaneous tissues is less severe but can lead to damage and requires treatment.Children with mild to moderate haemophilia may not have any signs or symptoms at birth, especially if they do not undergo circumcision. Their first symptoms are often frequent and large bruises and haematomas from frequent bumps and falls as they learn to walk. Swelling and bruising from bleeding in the joints, soft tissue, and muscles may also occur. Children with mild haemophilia may not have noticeable symptoms for many years. Often, the first sign in very mild haemophiliacs is heavy bleeding from a dental procedure, an accident, or surgery.
transplantation of stem cells derived another individual) has given better disease-free survival results than autologous transplantation and, based on recent uncontrolled studies, should be considered in DS-AMKL cases that have relapsed after their first chemotherapy-induced complete remission. Prognosis
The 5-year event free survival, disease-free survival, and overall survival rate in the phase 3 clinical study in DS-AMKL were 79, 89, 84 percent, respectively. Other studies that use a treatment regimen similar to that used in the phase 3 clinical study report overall survival rates of ~80% and long-term survivals of 74-91%. However, DS-AMKL patients who relapse following chemotherapy have a far poorer outlook with 3 year overall survival rate in one study of only 26%. There also appears to be little role for stem cell transplantation in DS-AMKL given the success of initial chemotherapy and the relatively poor results in DS-AMKL patients given this transplantation. Non-DS-AMKL
Pathophysiology
The most common genetic abnormality occurring in non-Down-AMKL is a nonreciprocal translocation between the short or p arm at position 13 on chromosome 1 (i.e. 1p13) and the p arm at position 13 on chromosome 22 (i.e. 22p13). Nonreciprocal translocations are exchanges of genes between two chromosomes that are not homologs, i.e. that are not maternal and paternal copies of the same chromosome. This particular translocation, designated t(1;22)(p13;q13), occurs mainly in infants but also is seen in children up to the age of 7 years with non-DS-AMKL. This translocation involves the RBM15 gene on chromosome 1 and the MKL1 gene (also termed MRTFA) on chromosome 22 to create a RBM15-MKL1 fusion gene.