What is Haemophilia?
• Haemophilia is a bleeding disorder that slows the
blood clotting process. People with this condition
experience prolonged bleeding.
• The major types of this condition are
haemophilia A (factor VIII deficiency) and
haemophilia B (factor IX deficiency
History of Haemophilia
• First recognized by the Jews
• It became known as the royal disease
• The word ‘haemophilia’ was first used in
• In 1952 haemophilia B was named after
CLASSIFICATION OF HAEMOPHILIA
CLASSIFICATION LEVEL OF FACTOR VII OR
IX IN THE BLOOD
Severe Less than 1% of normal
Moderate 1% to 5% of normal
Mild 5% to 30% of normal
• Haemophilia occur much more commonly in males.
• Haemophilia A is the most common type of the condition; 1 in
4,000 to 1 in 5,000 males worldwide are born with this
• Haemophilia B occurs in approximately 1 in 20,000 newborn
• By race/ethnicity, the prevalence is 13.2 cases in 100,000
among white males, 11.0 among African-American males, and
11.5 among Hispanic males.
• Haemophilia C occurs primarily among individuals of Jewish
BIOCHEMICAL BASIS OF HAEMOPHILIA
Homeostasis- Cessation of bleeding. Coagulation
Two types of hemostasis:
• Primary hemostasis: A platelet plug is formed
• Secondary hemostasis: Blood clot formation
•Factor VIII deficiency
•Factor IX deficiency
Gene Structure and Expression
•Hemophilia may be caused by a defect
in one of the genes that determine
how the body makes blood clotting
factor VIII or IX.
•The genes are located on the X
• Factor VIII gene- long arm in band q28
• Factor IX gene - q26.3-27.1
Biosynthesis and Biochemistry Factor VIII
•Factor VIII or antihemophilic factor
•A nonenzymatic protein
•2351 amino acids
•Circulates in plasma in complex with von Willibrand
•Biosynthesis occurs in the liver and spleen primarily.
•Function -participate in blood coagulation.
•It is a cofactor for factor IXa which converts factor
X to the activated form (Xa).
Biosynthesis and Biochemistry Factor IX
• Factor IX (Christmas factor, or hemophilia B factor)
• Produced as a zymogen and circulates in plasma.
• 415 amino acids.
• Is a member of the vitamin K–dependent protein family
• Is cleaved by factor XIa or factor VIIa to produce a two-chain
form where the chains are linked by a disulfide bridge.
• When activated into factor IXa, in the presence of Ca2+,
membrane phospholipids, and a Factor VIII cofactor, it
hydrolyses one arginine-isoleucine bond in factor X to form
• Function-in blood coagulation it activates factor X to factor Xa.
SIGNS and SYMPTOMS of HAEMOPHILIA
1. Excessive Bleeding: bleeding can occur
externally or internally
•Bleeding in the mouth from a cut or bite or
from cutting or losing a tooth
•Nosebleeds for no obvious reason
•Heavy bleeding from a minor cut
•Bleeding from a cut that resumes after
stopping for a short time
•Blood in the urine (from bleeding in the
kidneys or bladder)
•Blood in the stool (from bleeding in the
intestines or stomach)
•Large bruises (from bleeding into the
large muscles of the body)
Bleeding in the joints:
•Bleeding in the knees, elbows, or other joints is
another common form of internal bleeding
•The bleeding causes tightness in the joint with
no real pain or any visible signs of bleeding.
•The joint then becomes swollen, hot to touch,
and painful to bend. Swelling continues as
•Movement in the joint is temporarily lost
Bleeding in the brain:
•Long-lasting, painful headaches or neck
pain or stiffness
•Sleepiness or changes in behaviour
•Sudden weakness or clumsiness of the
arms or legs or problems walking
•Convulsions or seizures
• By family history
• Haemophilia is diagnosed by taking
sample and measuring the level of
factor activity in the blood.
• Treatment with Replacement Therapy
• Antifibrinolytic Medicines
• Treatment of a Specific Bleeding Site