Bleeding Disorders and Lab Testing

If you didn’t already know, bleeding disorders are classified as someone having the tendency to bruise easily or even bleed excessively for a long period of time. However, these usually come from genetics and can be inherited. These disorders can also be caused by various factors that come about during the lifetime of a person.  

From a general point of view, blood stays inside the blood vessels within the circulatory system. In the case of sustaining an injury to the blood vessels, bleeding begins. The human body relies on the complex clotting process of hemostasis to stop blood loss. In the primary stage of hemostasis, all injured blood vessels constrict to reduce the flow of blood.  

When blood flow is restricted, fragments of cells within the blood known as platelets stick to the injured part. They try to clump together with others as they release a series of chemical compounds. When the compounds are released, they aggregate the other platelets present, and together they form a very loose plug of the platelet.  

Platelets are responsible for supporting the coagulation of the cascade. This is simply a series of steps that require the activation of proteins. These proteins are referred to as the clotting factor or the coagulation factor.  

As this secondary process takes place, fibrin strands form and weave through any loose platelet that is found on the plug. After weaving, they compress to form a stable clot. The newly formed barrier then remains securely on the area until it is healed.  

The process of hemostasis is quite dynamic, and as soon as the clot is formed, several factors come into effect to reduce the speed of the process. After some time, the clot is then dissolved via fibrinolysis. This allows the clot to be removed after healing takes place. When persons are healthy, this balance exists to prevent excess bleeding and clots are successfully removed after healing.  

For these processes to take place, the elements needed for primary and secondary hemostasis must be there. However, they must also be activated at the right moment and be working properly to ensure that the clotting process takes place effectively. In the case of insufficient coagulation factors or platelets, stable clots will not form. This results in excessive bleeding.  

Bleeding disorders come about when there is a problem with the clotting process. If someone is suffering from a deficiency or components are not working properly or they are missing, disorders develop. Additionally, some disorders involve the blood vessel structure as well as the ability to produce healthy platelets.  

Bleeding disorders are rarely inherited and are known to be caused by dysfunctions of some type or a deficiency in the clotting element. If the disorder was acquired and there’s a high possibility that no genetic components existed. This means that it came about due to another factor.  

Signs and Symptoms 

Bleeding disorders have been known to result in some symptoms and signs. However, they are all dependent on the causes, and different combinations can exist. This leaves many symptoms and signs that all have a different degree of severity.  

For some, bleeding can begin early on during childhood. These episodes are sometimes mild or severe. In some instances, persons require surgery to deal with prolonged bleeding. Bleeding problems can also cause trauma and dental procedures. If they begin early on, there a chance that it was inherited.  

Some signs and symptoms may include: 

  • Bleeding gums 
  • Nosebleeds that occur frequently 
  • Easy or unexplained bruising 
  • Excessive bleeding from dental procedures or small cuts  
  • Muscle, joint pain or swelling after injuries and accidents that were minor 
  • Women who experience heavy, longer menstrual periods 
  • Purplish small spots or large lesions on the skin indicate bleeding under the skin 
  • Red spots that look like rash on the skin 
  • Bleeding in the eyes with loos of vision 
  • Chronic anemia 
  • Arthritic-type symptoms that come from bleeding into the joints 
  • Bleeding in the digestive tract that causes blood in the stool 

Tests 

If a doctor is suspicious of the symptoms and signs experienced by a patient, they can order several laboratory tests. To properly investigate the disorder, several steps must be followed. The following tests can be ordered if need be: 

In the case where PTT or PT or both result in the need for further testing, additional tests are performed to determine the problems associated with the coagulation factors. They also determine if there are specific inhibitors that could also be causing the problem. It should be noted that not all tests listed below are needed for persons suffering from bleeding disorders.  

Tests for Bleeding Disorders 

The following tests are some of the most common tests that are ordered by healthcare practitioners to further evaluate bleeding disorders: 

  • Blood Smear – Blood smears involve the microscopic examination of a blood sample. It goes on to further estimate and even evaluate the size and appearance of the platelets. This test is usually required if someone experiences bleeding without a cause or if they have an abnormal platelet count. However, abnormal platelets tend to point toward platelet disorders.  
  • Complete Blood Count (CBC) – Blood cells are categorized and counted. These include the white blood cells (WBCs), red blood cells (RBCs) and platelets. This test is carried out to perform routine screening or general tests. These usually detect underlying anemia and other abnormalities. Decreased platelet counts are also identified with the CBC and can signal a platelet disorder just like anemia can suggest excessive bleeding.  
  • Coagulation Factors, Activity – The activity or function of coagulation factors are measured with this test. However, this test is only needed when the PTT or PT results were not normal. A decreased activity level usually indicates a deficiency or a specific factor inhibitor.  
  • Coagulation Factors, Antigen – The coagulation factor antigen test is used to measure the number of factors present. This test is done when a specific factor is low. Lower levels usually indicate a factor deficiency that was caused by an increase or a decrease of a factor.  
  • D-dimer – The types of degradation cross-linked fibrin products are measured with this test. Hence, blood clot formation is evaluated during the bleeding and clotting phases. When elevated, it means that clotting occurred recently. This can occur because of disseminated intravascular coagulation (DIC) or blood clots (thrombosis).  
  • Factor Inhibitors – These detect the antibodies that are directed at coagulation factors. If the coagulation factor test was out of the normal range, this test is requested. If for some reason, it is present, some factors are specific and indicate deficiencies.  
  • Fibrinogen (activity) – This gives a better indication of the activity as well as the ability of the clotting indicator. Hence, clots and bleeding are evaluated. These elevate when someone sustains an infection or is suffering from inflammation.  

The previously mentioned tests are carried out because of the following: 

  • PTT – Factors I (fibrinogen), II (prothrombin), V, VIII, IX, X, XI, XII, prekallikrein (PK) and high weight kininogen (HMWK) are evaluated on a general screen. During this analysis, bleeding is investigated. If prolonged PTT is suggested, then further tests can indicate nonspecific inhibitors such as the anticoagulant of lupus, a coagulation factor deficiency, or even a specific inhibitor like the antibody factor VIII.  
  • Aggregation studies or Platelet Function Tests – Studies the ability of the platelets to clump or adhere to a damaged spot. Further evaluation of bleeding is done if normal levels occur. In the case of abnormal values, the presence of von Willebrand disease could be present.  
  • PT – The factors I (fibrinogen), II, V, VII, and X are examined on the general screen. If prolonged, further testing can result in dysfunction, coagulation deficiency, or a specific factor deficiency.  
  • Ristocetin Cofactor – Measures the von Willebrand factors (VWF) function or activity. Bleeding episodes are evaluated with this test, and when decreased, the VWF factor less active. Hence, platelets don’t adhere to an injury site.  
  • Thrombin Time (TT) – The TT test detects the time required for thrombin to activate fibrinogen to form the fibrin strands. Bleeding episodes are also evaluated, and if PTT is prolonged, the sample could have been contaminated by heparin. When elevated, heparin is suspected as the contaminant. Additionally, elevation also indicates the degradation of fibrin products, abnormal levels of fibrin, or even abnormally low levels.  
  • The von Willebrand Factor Antigen – Successfully measures the activity of VWF. If low, bleeding episodes are then evaluated. Low levels usually indicate conditions that were derived from acquired platelet conditions. There is also a risk of bleeding.  
  • Thromboelastography (TEG) – TEG evaluates the clotting abilities. Platelet functions, clot breakdown, and coagulation factors are also assessed. Prolonged bleeding or excessive bleeding after major surgery is also assessed with the TEG test. Results that are not in the normal range express a qualitative or quantitative platelet defect, or fibrinolytic and coagulation factors. These results are useful in determining the treatment and management of blood transfusion.  

Along with those mentioned, metabolic panels can also be ordered. These perform a thorough assessment of the kidney and liver functions. In the case of kidney or liver failure or both, patients have a higher risk of experiencing increased bleeding.