Hemophilia is a bleeding disorder that prevents blood from clotting normally. Understanding when hemophilia is typically diagnosed is crucial for families, especially those with a known history of the condition. While there isn’t a fixed “average age,” diagnosis timing varies based on the severity of hemophilia and circumstances surrounding testing. This article will explore factors influencing the age of diagnosis and the importance of early detection.
Who Should Be Tested for Hemophilia?
Testing for hemophilia is recommended in several situations, primarily focusing on individuals with a higher risk profile.
Families with a History of Hemophilia or Bleeding Disorders
A significant indicator for hemophilia testing is a family history of bleeding issues. If there’s a known history of hemophilia or unexplained bleeding in male relatives—such as brothers, maternal uncles, grandfathers, or cousins—it’s essential to discuss this with a healthcare provider. A doctor will often take a detailed family medical history to assess the likelihood of a bleeding disorder.
For families with a known history, newborn babies are often tested soon after birth. This proactive approach ensures early identification and management of hemophilia. Testing is especially crucial for:
- Babies born into families with a confirmed history of hemophilia.
- Babies whose mothers are known to be carriers of the hemophilia gene.
- Babies who exhibit bleeding symptoms at birth.
Alt text: A gloved hand carefully holds a vial of blood, emphasizing the importance of blood samples in diagnostic testing for conditions like hemophilia.
Umbilical cord blood testing is frequently used for newborns. It’s particularly effective at detecting low levels of factor VIII, associated with hemophilia A. However, factor IX, relevant to hemophilia B, develops more slowly in infants. Therefore, a slightly low factor IX level at birth might not definitively indicate hemophilia B, and a repeat test later, around 6 months of age, might be necessary for conclusive results. Understanding the inheritance pattern for hemophilia can also guide testing decisions.
Families with No Prior History of Hemophilia
Interestingly, about one-third of babies diagnosed with hemophilia have no known family history of the disorder. In these cases, diagnosis often occurs when unusual bleeding symptoms are observed. Doctors may consider hemophilia testing in newborns if they present with:
- Prolonged bleeding following circumcision.
- Extended bleeding after routine procedures like blood draws or heel sticks for newborn screenings.
- Bleeding in the scalp or brain after a difficult delivery, especially if instruments like vacuum extractors or forceps were used.
- Unexplained, raised bruises or an unusually high number of bruises.
If hemophilia isn’t diagnosed in the newborn period, parents might notice excessive bruising as their child begins to crawl or stand.
When is Hemophilia Typically Diagnosed?
The age of diagnosis is significantly influenced by the severity of hemophilia.
Severe Hemophilia: Individuals with severe hemophilia often experience significant bleeding problems early in life. Consequently, they are frequently diagnosed within the first year of life. The prominent and immediate bleeding symptoms in severe cases lead to earlier detection and prompt medical evaluation.
Mild to Moderate Hemophilia: People with milder forms of hemophilia might not exhibit such immediate or severe symptoms. As a result, their diagnosis can be delayed until later in childhood or even adulthood. Milder forms may only become apparent after injuries, surgeries, or dental procedures where prolonged bleeding is observed. In some cases, diagnosis might not occur until adulthood following a major injury or surgery.
Average Age Range: While pinpointing a precise Average Age Of Hemophilia Diagnosis is challenging due to varying severities and diagnostic pathways, most cases are identified in early childhood. Severe hemophilia is typically diagnosed in infancy, while milder forms may be diagnosed later in childhood or even adulthood.
Types of Tests for Hemophilia Diagnosis
Diagnosing hemophilia involves a combination of screening tests and clotting factor tests.
Screening Tests
Screening tests are blood tests designed to assess if blood is clotting correctly. These tests provide an initial indication of potential clotting issues. Common screening tests include:
Complete Blood Count (CBC)
A CBC measures various components of the blood, including hemoglobin levels, red and white blood cell counts, and platelet counts. While a CBC might be normal in individuals with hemophilia, it can reveal low hemoglobin and red blood cell counts if significant bleeding has occurred.
Activated Partial Thromboplastin Time (APTT) Test
The APTT test measures the time it takes for blood to clot, specifically assessing the function of clotting factors VIII, IX, XI, and XII. A prolonged clotting time in this test is a strong indicator of hemophilia A or B, as these conditions involve deficiencies in factors VIII and IX respectively.
Prothrombin Time (PT) Test
Similar to APTT, the PT test also measures clotting time but focuses on factors I, II, V, VII, and X. The PT test results are typically normal in people with hemophilia A and B, as it primarily assesses different clotting factors than those deficient in these types of hemophilia.
Fibrinogen Test
The fibrinogen test evaluates the level of fibrinogen, also known as clotting factor I, in the blood. It’s often ordered in conjunction with other clotting tests or if APTT or PT results are abnormal. Fibrinogen is essential for blood clot formation.
Clotting Factor Tests
Clotting factor tests, or factor assays, are crucial for definitive hemophilia diagnosis. They measure the activity levels of factor VIII and factor IX in the blood. These tests not only confirm the presence of a bleeding disorder but also identify the specific type of hemophilia (A or B) and its severity. Knowing the type and severity is vital for developing an effective treatment plan.
Hemophilia Severity Classification
The severity of hemophilia is classified based on baseline clotting factor activity, measured before any treatment. This baseline level represents an individual’s inherent clotting ability. Factor levels are reported as a percentage of normal, with the average normal range being 50% to 150%.
The International Society on Thrombosis and Hemostasis (ISTH) established the following hemophilia severity categories in 2001:
| Severity | Levels of factor VIII (8) or factor IX (9) in the blood |
|---|---|
| Mild hemophilia | Greater than 5% but less than 40% |
| Moderate hemophilia | 1% to 5% |
| Severe hemophilia | Less than 1% |
It’s important to note that individuals, particularly women and girls with a hemophilia gene, can have factor levels ≥40%. ISTH recommends the terms “symptomatic carrier” for those with bleeding symptoms and “asymptomatic carrier” for those without, in this factor level range.
Conclusion
While the “average age of hemophilia diagnosis” is not a single number, understanding the factors influencing diagnosis timing is vital. Severe hemophilia is often diagnosed in infancy due to early and pronounced bleeding, while milder forms might be diagnosed later in childhood or adulthood. Prompt testing for individuals with a family history or suggestive symptoms is crucial for early diagnosis and management, leading to better health outcomes for those living with hemophilia. Early diagnosis allows for proactive treatment and management strategies, significantly improving the quality of life for individuals with hemophilia.
