Antiphospholipid Syndrome

Description: The Lupus Anticoagulant Evaluation test is used to screen for lupus anticoagulants, also known as antibodies with phospholipid-protein specificity.

Also Known As: LA Test, LAC Test, Lupus Anticoagulant Panel Test, Lupus Inhibitor Test, LA Sensitive PTT Test, PTT-LA Test,

Collection Method: Blood Draw

Specimen Type: Plasma

Test Preparation: No preparation required

Test Includes Reflexes:

PTT-LA and dRVVT with Reflex Confirmations

• If PTT-LA Screen is prolonged (>40 seconds), then Hexagonal Phase Confirmation will be performed at an additional charge (CPT code(s): 85598).
• If Hexagonal Phase Confirmation is positive or weakly positive, then Thrombin Clotting Time will be performed at an additional charge (CPT code(s): 85670).
• If dRVVT Screen is prolonged (>45 seconds), then dRVVT Confirm will be performed at an additional charge (CPT code(s): 85597).
• ?If dRVVT Confirm is positive, then dRVVT 1:1 Mixing Study will be performed at an additional charge (CPT code(s): 85613).

When is a Lupus Anticoagulant test ordered?

Testing for lupus anticoagulant is recommended in addition to other tests when:

• A vein or artery has had an inexplicable blood clot; signs and symptoms might range from exhaustion, sweating, and rapid breathing with a pulmonary embolism to discomfort, swelling, and discolouration in the leg with deep vein thrombosis.
• A person can have APS symptoms, which may resemble the ones listed above.
• A woman has repeated miscarriages.
• A individual undergoes an extended PTT test.
• Particularly for people being tested for APS, testing is typically repeated about 12 weeks after the initial results to ensure that the presence of lupus anticoagulant is still present.

A doctor may occasionally repeat one or more of the lupus anticoagulant screening tests, typically the PTT, on a person who first tests negative for the substance but who nonetheless has an autoimmune disease like lupus to see if the antibody has grown since the previous time the test was conducted. The reason for this is because the lupus anticoagulant could manifest in the person at any time.

What does a Lupus Anticoagulant blood test check for?

Autoantibodies, which are made by the immune system that mistakenly target specific parts of the body's own cells, are lupus anticoagulants. They specifically target phospholipids and phospholipid-associated proteins that are present in the cell's outermost layer. These autoantibodies raise a person's chance of getting a blood clot by interfering with the blood clotting process in a mechanism that is not completely understood. A battery of tests known as lupus anticoagulant testing can find LA in blood.

The name of the lupus anticoagulant test may sound strange or be unclear for two reasons:

• Although LA testing is not used to diagnose lupus and LA are commonly absent in lupus patients, lupus anticoagulants were originally discovered in patients with the inflammatory disease. LA can also happen to persons who have other medical issues or take certain medications. About 2-4% of the general population has antibodies, and those with no known risk factors can nevertheless develop them.
• Since LA really reduces clotting in laboratory tests used to assess coagulation, the term "anticoagulant" is a part of the name. For instance, they prevent the clotting-causing chemical processes in the partial thromboplastin time test, which is frequently used to gauge clotting. However, the presence of LA in the human body is linked to a higher risk of unneeded blood clot formation. It's important to note that lupus anticoagulant doesn't by itself make the body bleed.

Lupus anticoagulant cannot be readily measured and is not detectable by a single test. Utilizing a panel of consecutive tests for which there is no standardization, LA is typically detected.

Initial testing usually consists of one or more phospholipid-based assays, such as the PTT, the LA-sensitive PTT, or the diluted Russell viper venom test. All of these tests track the length of time needed for a sample to clot; LA increases that length of time.

To confirm or rule out the presence of lupus anticoagulant, certain follow-up tests are carried out according on the outcomes of these initial tests.

LA may make it more likely for blood clots to form in arteries and veins, frequently in the legs' veins. These clots have the potential to obstruct blood flow to any area of the body, resulting in pulmonary embolism, heart attack, or stroke. LA is linked to repeated miscarriages as well. It has been hypothesized that LA may directly destroy the tissue of the placenta, impairing its development, and that LA may also induce clots to form that clog blood arteries of the placenta, impairing growth of the unborn baby.

One of the three principal antiphospholipid antibodies linked to a higher risk of thrombosis and antiphospholipid antibody syndrome, an autoimmune condition characterized by excessive blood clot formation and pregnancy-related problems, is the lupus anticoagulant. Beta-2 glycoprotein 1 antibody and cardiolipin antibodies make up the other two. Both separately and collectively, they enhance a person's propensity to clot improperly. If all three antibodies are present, people with APS are more likely to clot. However, those with LA seem to experience thrombosis more frequently.

Antiphospholipid antibodies do not always cause symptoms. About 5% of healthy adults have antiphospholipid antibodies.

Lab tests often ordered with a Lupus Anticoagulant test:

• Antiphospholipid Antibodies
• PTT
• Thrombin Time
• PT and INR
• Homocysteine
• Cardiolipin Antibodies
• Protein C and S
• Factor V Leiden Mutation
• Beta-2 Glycoprotein 1 Antibodies

Conditions where a Lupus Anticoagulant test is recommended:

• Excessive Clotting Disorders
• Autoimmune Disorders
• Lupus
• Antiphospholipid Syndrome

How does my health care provider use a Lupus Anticoagulant test?

Testing for lupus anticoagulant is a set of procedures used to find the anticoagulant in blood. An autoantibody called LA is linked to excessive blood clot formation. Testing with LA may be done to assist identify the root cause of:

• a mysterious blood clot in an artery or vein
• Multiple miscarriages
• an extended PTT test without explanation. LA testing assists in determining if a prolonged PTT is caused by a nonspecific inhibitor, such as the lupus anticoagulant, or a nonspecific inhibitor, such as an antibody against a particular coagulation factor.

Using LA testing also allows for:

• Antiphospholipid syndrome is diagnosed with testing for cardiolipin antibody and anti-beta2-glycoprotein I.
• To help with the diagnosis of an excessive clotting condition, tests like factor V Leiden or proteins C and S are often used.
• Identifying the transient or persistent nature of the lupus anticoagulant

There is no single test or established process to identify LA in blood, and it cannot be quantified directly. The presence or absence of the autoantibody is determined by a set of tests:

• It is advised to perform two tests to find lupus anticoagulant. The two assays with the highest sensitivity are the LA-sensitive PTT and the dilute Russell viper venom test, both of which utilize very little phospholipid reagent. To confirm or rule out the presence of lupus anticoagulant, follow-up testing is done. These may consist of:
• Mixing study: A PTT or DRVVT is run on the mixture after an equal volume of patient plasma and "normal" pooled plasma have been combined.
• Correction/neutralization: A PTT-LA or DRVVT is carried out after adding an excessive amount of phospholipids to the patient sample.

What do my Lupus Anticoagulant test results mean?

The outcomes of the several LA tests either point in the direction of LA or away from it. The lab report could be a little technical, but it typically gives an explanation of the findings and indicates if LA is present or not. The best people to interpret the results of LA testing, like the results of other tests for clotting problems, are medical professionals with experience in excessive clotting diseases.

Even though the initial LA tests may differ, they often start with a PTT that is extended. Normal PTT results could indicate the absence of LA. The LA-sensitive PTT may be required since the test may not be sensitive enough to identify LA.

To help with the diagnosis of antiphospholipid syndrome, lupus anticoagulant testing is frequently combined with tests for cardiolipin antibody and anti-beta2-glycoprotein I antibodies.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

ANAlyzeR™ ANA, IFA with Reflex Titer/Pattern, Systemic Autoimmune Panel 1

Includes

• ANA Screen,IFA, with Reflex to Titer and Pattern
• DNA (ds) Antibody, Crithidia IFA with Reflex to Titer
• Chromatin (Nucleosomal) Antibody
• Sm Antibody
• Sm/RNP Antibody
• RNP Antibody
• Sjogren's Antibodies (SS-A, SS-B)
• Scleroderma Antibody (Scl-70)
• Jo-1 Antibody
• Centromere B Antibody
• Complement Component C3c and C4c
• Cardiolipin Antibodies (IgA, IgG, IgM)
• Beta-2-Glycoprotein I Antibodies (IgG, IgA, IgM)
• Rheumatoid Factor (IgA, IgG, IgM)
• Cyclic Citrullinated Peptide (CCP) Antibody (IgG)
• 14.3.3 eta Protein
• Thyroid Peroxidase Antibodies (TPO)

• If ANA Screen, IFA is positive, then ANA Titer and Pattern will be performed at an additional charge (CPT code(s): 86039).
• If the DNA (ds) Antibody Screen is positive, then DNA (ds) Antibody Titer will be performed at an additional charge (CPT code(s): 86256).

Alternative Name(s)

Expanded ANA Antibodies,Systemic Autoimmune Disorder,ANA and Expanded AI Testing,ANA and Systemic Autoimmunity,Comprehensive AI Testing,Early Systemic Autoimmune Disease,Autoimmune Disorders

Description: A CBC or Complete Blood Count with Differential and Platelets test is a blood test that measures many important features of your blood’s red and white blood cells and platelets. A Complete Blood Count can be used to evaluate your overall health and detect a wide variety of conditions such as infection, anemia, and leukemia. It also looks at other important aspects of your blood health such as hemoglobin, which carries oxygen. 

Also Known As: CBC test, Complete Blood Count Test, Total Blood Count Test, CBC with Differential and Platelets test, Hemogram test  

Collection Method: Blood Draw 

Specimen Type: Whole Blood 

Test Preparation: No preparation required 

When is a Complete Blood Count test ordered?  

The complete blood count (CBC) is an extremely common test. When people go to the doctor for a standard checkup or blood work, they often get a CBC. Suppose a person is healthy and their results are within normal ranges. In that case, they may not need another CBC unless their health condition changes, or their healthcare professional believes it is necessary. 

When a person exhibits a variety of signs and symptoms that could be connected to blood cell abnormalities, a CBC may be done. A health practitioner may request a CBC to help diagnose and determine the severity of lethargy or weakness, as well as infection, inflammation, bruises, or bleeding. 

When a person is diagnosed with a disease that affects blood cells, a CBC is frequently done regularly to keep track of their progress. Similarly, if someone is being treated for a blood condition, a CBC may be performed on a regular basis to see if the treatment is working. 

Chemotherapy, for example, can influence the generation of cells in the bone marrow. Some drugs can lower WBC counts in the long run. To monitor various medication regimens, a CBC may be required on a regular basis. 

What does a Complete Blood Count test check for? 

The complete blood count (CBC) is a blood test that determines the number of cells in circulation. White blood cells (WBCs), red blood cells (RBCs), and platelets (PLTs) are three types of cells suspended in a fluid called plasma. They are largely created and matured in the bone marrow and are released into the bloodstream when needed under normal circumstances. 

A CBC is mainly performed with an automated machine that measures a variety of factors, including the number of cells present in a person's blood sample. The findings of a CBC can reveal not only the quantity of different cell types but also the physical properties of some of the cells. 

Significant differences in one or more blood cell populations may suggest the presence of one or more diseases. Other tests are frequently performed to assist in determining the reason for aberrant results. This frequently necessitates visual confirmation via a microscope examination of a blood smear. A skilled laboratory technician can assess the appearance and physical features of blood cells, such as size, shape, and color, and note any anomalies. Any extra information is taken note of and communicated to the healthcare provider. This information provides the health care provider with further information about the cause of abnormal CBC results. 

The CBC focuses on three different types of cells: 

WBCs (White Blood Cells) 

The body uses five different types of WBCs, also known as leukocytes, to keep itself healthy and battle infections and other types of harm. The five different leukocytes are eosinophiles, lymphocytes, neutrophiles, basophils, and monocytes. They are found in relatively steady numbers in the blood. Depending on what is going on in the body, these values may momentarily rise or fall. An infection, for example, can cause the body to manufacture more neutrophils in order to combat bacterial infection. The amount of eosinophils in the body may increase as a result of allergies. A viral infection may cause an increase in lymphocyte production. Abnormal (immature or mature) white cells multiply fast in certain illness situations, such as leukemia, raising the WBC count. 

RBCs (Red Blood Cells) 

The bone marrow produces red blood cells, also known as erythrocytes, which are transferred into the bloodstream after maturing. Hemoglobin, a protein that distributes oxygen throughout the body, is found in these cells. Because RBCs have a 120-day lifespan, the bone marrow must constantly manufacture new RBCs to replace those that have aged and disintegrated or have been lost due to hemorrhage. A variety of diseases, including those that cause severe bleeding, can alter the creation of new RBCs and their longevity. 

The CBC measures the number of RBCs and hemoglobin in the blood, as well as the proportion of RBCs in the blood (hematocrit), and if the RBC population appears to be normal. RBCs are generally homogeneous in size and shape, with only minor differences; however, considerable variances can arise in illnesses including vitamin B12 and folate inadequacy, iron deficiency, and a range of other ailments. Anemia occurs when the concentration of red blood cells and/or the amount of hemoglobin in the blood falls below normal, resulting in symptoms such as weariness and weakness. In a far smaller percentage of cases, there may be an excess of RBCs in the blood (erythrocytosis or polycythemia). This might obstruct the flow of blood through the tiny veins and arteries in extreme circumstances. 

Platelets 

Platelets, also known as thrombocytes, are small cell fragments that aid in the regular clotting of blood. A person with insufficient platelets is more likely to experience excessive bleeding and bruises. Excess platelets can induce excessive clotting or excessive bleeding if the platelets are not operating properly. The platelet count and size are determined by the CBC. 

Lab tests often ordered with a Complete Blood Count test: 

• Reticulocytes
• Iron and Total Iron Binding Capacity
• Basic Metabolic Panel
• Comprehensive Metabolic Panel
• Lipid Panel
• Vitamin B12 and Folate
• Prothrombin with INR and Partial Thromboplastin Times
• Sed Rate (ESR)
• C-Reactive Protein
• Epstein-Barr Virus
• Von Willebrand Factor Antigen

Conditions where a Complete Blood Count test is recommended: 

• Anemia
• Aplastic Anemia
• Iron Deficiency Anemia
• Vitamin B12 and Folate Deficiency
• Sickle Cell Anemia
• Heart Disease
• Thalassemia
• Leukemia
• Autoimmune Disorders
• Cancer
• Bleeding Disorders
• Inflammation
• Epstein-Barr Virus
• Mononucleosis

Commonly Asked Questions: 

How does my health care provider use a Complete Blood Count test? 

The complete blood count (CBC) is a common, comprehensive screening test used to measure a person's overall health status.  

What do my Complete Blood Count results mean? 

A low Red Blood Cell Count, also known as anemia, could be due many different causes such as chronic bleeding, a bone marrow disorder, and nutritional deficiency just to name a few. A high Red Blood Cell Count, also known as polycythemia, could be due to several conditions including lung disease, dehydration, and smoking. Both Hemoglobin and Hematocrit tend to reflect Red Blood Cell Count results, so if your Red Blood Cell Count is low, your Hematocrit and Hemoglobin will likely also be low. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Differential results mean? 

A low White Blood Cell count or low WBC count, also known as leukopenia, could be due to a number of different disorders including autoimmune issues, severe infection, and lymphoma. A high White Blood Cell count, or high WBC count, also known as leukocytosis, can also be due to many different disorders including infection, leukemia, and inflammation. Abnormal levels in your White Blood Cell Count will be reflected in one or more of your different white blood cells. Knowing which white blood cell types are affected will help your healthcare provider narrow down the issue. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Platelet results mean? 

A low Platelet Count, also known as thrombocytopenia, could be due to a number of different disorders including autoimmune issues, viral infection, and leukemia. A high Platelet Count, also known as Thrombocytosis, can also be due to many different disorders including cancer, iron deficiency, and rheumatoid arthritis. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

NOTE: Only measurable biomarkers will be reported. Certain biomarkers do not appear in healthy individuals. 

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Reflex Parameters for Manual Slide Review

CBC Reflex Pathway

Step 1 - The slide review is performed by qualified Laboratory staff and includes:

• Confirmation of differential percentages
• WBC and platelet estimates, when needed
• Full review of RBC morphology
• Comments for toxic changes, RBC inclusions, abnormal lymphs, and other
• significant findings
• If the differential percentages agree with the automated counts and no abnormal cells are seen, the automated differential is reported with appropriate comments

Step 2 - The slide review is performed by qualified Laboratory staff and includes: If any of the following are seen on the slide review, Laboratory staff will perform a manual differential:

• Immature, abnormal, or toxic cells
• nRBC’s
• Disagreement with automated differential
• Atypical/abnormal RBC morphology
• Any RBC inclusions

Step 3 - If any of the following are seen on the manual differential, a Pathologist will review the slide:

• WBC<1,500 with abnormal cells noted
• Blasts/immature cells, hairy cell lymphs, or megakaryocytes
• New abnormal lymphocytes or monocytes
• Variant or atypical lymphs >15%
• Blood parasites
• RBC morphology with 3+ spherocytes, RBC inclusions, suspect Hgb-C,
• crystals, Pappenheimer bodies or bizarre morphology
• nRBC’s

Description: A PTT test is used to diagnose and monitor bleeding disorders or excessive clotting disorders. The biomarker in the test is used to measure the tsime it takes for the blood to form a clot.

Also Known As: Activated Partial Thromboplastin Time Test, aPTT test, PTT Test

Collection Method: Blood Draw

Specimen Type: Whole Blood

Test Preparation: No preparation required

When is Partial Thromboplastin Time test ordered?

When a person has the following symptoms, the PTT may be ordered along with other tests, such as a PT:

• Bleeding that isn't explained or bruises that isn't easy to get rid of
• A blood clot in a vein or artery is a serious condition.
• Disseminated intravascular coagulation
• A chronic disorder that affects hemostasis, such as liver disease

A PTT can be requested in the following situations:

• When a person develops a blood clot or a woman has repeated miscarriages, as part of a lupus anticoagulant, anticardiolipin antibodies, or antiphospholipid syndrome examination
• When a person is on standard heparin therapy, the two are overlapped and both the PTT and PT are monitored until the person has stabilized. When a person is switched from heparin therapy to extended warfarin therapy, the two are combined and both the PTT and PT are monitored until the person has stabilized
• Prior to surgery, if there is a high risk of blood loss and/or if the patient has a history of bleeding, such as frequent or severe nasal bleeds and easy bruising, which could suggest the presence of a bleeding problem

What does a Partial Thromboplastin Time blood test check for?

The partial thromboplastin time is a screening test that determines a person's capacity to form blood clots properly. It counts how long it takes for a clot to develop in a person's blood sample after chemicals have been administered. The PTT evaluates the number and function of specific proteins known as coagulation factors, which are crucial in blood clot formation.

When bodily tissues or blood vessel walls are harmed, bleeding ensues, and hemostasis is initiated. Platelets are little cell fragments that cling to the damage site and subsequently clump together. A process known as the coagulation cascade begins at the same time, and coagulation factors are activated. Fibrin threads develop and crosslink into a net that attaches to the damage site and stabilizes it as a result of the cascade reactions. This, combined with the platelets sticking, forms a stable blood clot that seals off injuries to blood arteries, prevents further blood loss, and allows damaged areas to heal.

For appropriate blood clot formation, each component of this hemostatic mechanism must operate effectively and be present in sufficient quantities. If one or more of these factors are deficient, or if they function improperly, a stable clot may not form, and bleeding may continue.

A PTT compares a person's sample to a normal clotting time reference period. A person's PTT is considered "prolonged" if it takes longer than usual to clot. A prolonged PTT could be caused by a disease that causes one or more coagulation factors to diminish or become dysfunctional. It's also possible that it's caused by a disorder in which the body creates antibodies that attack one or more coagulation factors, impairing their activity.

A PTT may take longer than expected if the person being tested creates an autoantibody termed an antiphospholipid antibody, which interferes with the test. Because it targets phospholipids, which are employed in the PTT, this type of antibody has an effect on the test findings. Antiphospholipid antibodies can extend the PTT test result, although they are linked to increased clotting in the body. A person who makes these antibodies may be more susceptible to blood clots. A PTT could be used to assess someone who has signs and symptoms of excessive clotting or antiphospholipid syndrome.

A PTT is frequently ordered in conjunction with a prothrombin time while investigating bleeding or clotting episodes. The results of these tests will be analyzed by a health professional in order to discover the reason of bleeding or clotting episodes.

Coagulation tests like the PT and PTT are now known to be reliant on what happens artificially in the test setting and so do not always reflect what happens in the body. They can, however, be utilized to assess certain aspects of the hemostasis system. The PTT and PT tests measure coagulation components that are part of the intrinsic, extrinsic, and common chemical reaction pathways in the cascade, respectively.

Lab tests often ordered with a Partial Thromboplastin Time test:

• PT and INR
• Fibrinogen
• D-Dimer
• Lupus Anticoagulant
• ACT
• Coagulation Factors
• Platelet Count
• Complete Blood Count (CBC)
• Von Willebrand Factor
• Antiphospholipid Antibodies

Conditions where a Partial Thromboplastin Time test is recommended:

• Bleeding Disorders
• Excessive Clotting Disorders
• Vitamin K Deficiency
• DIC
• Antiphospholipid Syndrome

How does my health care provider use a Partial Thromboplastin Time test?

The PTT is mostly used to look into unexplained bleeding or clotting. It may be ordered in conjunction with a prothrombin time test to assess hemostasis, the body's process of forming blood clots to stop bleeding. Excessive bleeding or clotting issues are frequently investigated with these tests as a starting point.

Coagulation factors are proteins that have a role in hemostasis and the development of blood clots. When an injury occurs and bleeding begins, coagulation factors are triggered in a series of events that finally assist in the formation of a clot.

Prekallikrein and high molecular weight kininogen, as well as coagulation factors XII, XI, IX, VIII, X, V, II, and I, are all assessed using the PTT. The coagulation factors VII, X, V, II, and I are evaluated in a PT test. A health practitioner can determine what type of bleeding or clotting condition is present by combining the findings of the two tests. The PTT and PT aren't diagnostic, but they can help you figure out if you need more tests.

The following are some examples of PTT applications:

• To detect coagulation factor deficit; if the PTT is extended, additional tests can be performed to ascertain whether coagulation factors are deficient or malfunctioning, or to see if the blood contains an antibody to a coagulation factor.
• Nonspecific autoantibodies, such as lupus anticoagulant, can be detected and are linked to clotting episodes and recurrent miscarriages. As a result, PTT testing may be included in a clotting disorder panel to aid in the investigation of recurrent miscarriages or the diagnosis of antiphospholipid syndrome. The LA-sensitive PTT, a version of the PTT, could be used for this.
• Heparin is an anticoagulant medicine that is given intravenously or by injection to prevent and treat blood clots; it is used to monitor routine heparin anticoagulant therapy. PTT is extended as a result of it. Heparin must be constantly managed when it is used for medicinal purposes. If too much is given, the patient may bleed excessively; if not enough is given, the patient may continue to clot.

The PTT and PT tests are sometimes used to screen for potential bleeding tendencies before surgical or other invasive treatments based on carefully acquired patient histories.

Other tests that may be done in conjunction with a PTT or in response to aberrant results include:

• Platelet count — should be checked often during heparin therapy to detect any thrombocytopenia caused by the drug.
• Thrombin time testing – used to rule out the possibility of heparin contamination.
• Fibrinogen testing - to rule out a low level of fibrinogen as the cause of a delayed PTT.
• A second PTT test is conducted after a first PTT is delayed by mixing the person's plasma with pooled normal plasma.  If the PTT time returns to normal, it indicates that one or more coagulation factors in the person's plasma are deficient. If the condition persists, it could be caused by the presence of an aberrant specific factor inhibitor or nonspecific lupus anticoagulant.
• Coagulation factor tests are used to determine how active coagulation factors are. They can identify low protein levels or proteins that aren't working properly. A coagulation factor's antigen level is occasionally tested.
• If the presence of lupus anticoagulant is suspected, a test for dilute Russell viper venom may be performed.
• Von Willebrand factor is a test that is sometimes conducted to see if von Willebrand disease is causing a prolonged PTT.

What do my Partial Thromboplastin Time test results mean?

PTT findings are usually available in seconds. A normal clotting function is usually indicated by a PTT result that falls within a laboratory's reference interval. However, a single coagulation factor deficiency may be present in low to moderate amounts. The PTT should not be extended until the factor levels have dropped to 30% to 40% of normal. Lupus anticoagulant may also be present, but it is unlikely to affect the PTT result. A more sensitive LA-sensitive PTT or a dilute Russell viper venom time can be used to test for the lupus anticoagulant if it is suspected.

A delayed PTT indicates that clotting is taking longer than usual and could be caused by a number of factors. This frequently indicates that the body's clotting ability is being harmed by a coagulation factor deficit or a particular or nonspecific antibody. Defects in coagulation factors can be acquired or inherited.

It's possible that prolonged PTT tests are caused by:

• Von Willebrand disease is the most prevalent inherited bleeding disorder, and it inhibits platelet function because von Willebrand factor levels are low.
• Hemophilia A and B are two more inherited bleeding disorders that are caused by a lack of factors VIII and IX, respectively.
• Other coagulation factors, such as factors XII and XI, are deficient.

Deficiencies in acquired factors:

• A vitamin K insufficiency. Vitamin K is required for the production of clotting factors. Vitamin K deficiency is uncommon, but it can occur as a result of a poor diet, malabsorption issues, or the use of certain antibiotics over an extended period of time, for example.
• Because the liver produces the majority of coagulation components, liver illness might result in extended PT and PTT. PT is more likely to be prolonged than PTT in patients with liver disease and vitamin K insufficiency.
• A nonspecific inhibitor, such as lupus anticoagulant—the presence of these inhibitors is usually linked to abnormal clotting, but they can also lengthen the PTT. For further information, see the individual test articles.
• Antibodies that selectively target certain coagulation factors, such as antibodies that target factor VIII, are known as specific inhibitors. They can form in people who are receiving factor replacements or they can develop spontaneously as an autoantibody in people who have a bleeding condition. Factor-specific inhibitors have the potential to induce serious bleeding.
• Heparin is an anticoagulant that will prolong a PTT if it is present in the sample as a contaminant or as part of anticoagulation therapy. The goal PTT for anticoagulant therapy is usually 1.5 to 2.5 times longer than the pretreatment level.
• The PTT is not used to monitor warfarin anticoagulation therapy, but it may be influenced by it. The PT is commonly used to track warfarin therapy.
• Anticoagulation therapy with a direct thrombin inhibitor or a direct factor Xa inhibitor are examples of other anticoagulants.
• Leukemia, severe bleeding in pregnant women prior to or after delivery, and recurrent miscarriages can all cause elevated PTT levels

The PTT results are frequently combined with the PT results to determine what ailment is present.

PTT testing may be shortened as a result of:

• Disseminated intravascular coagulation—circulating procoagulants shorten the PTT in the early phases of DIC.
• Extensive cancer
• An acute-phase reaction is a disease that causes significant tissue inflammation or trauma, which causes factor VIII levels to rise. It's frequently a one-time occurrence that isn't tracked with a PTT test. The PTT will return to normal once the condition that caused the acute phase reaction is resolved.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Description: A Prothrombin Time test will measure the speed of which your blood clots. This test can be used to detect a bleeding or clotting disorder or to determine in your blood is clotting too fast or too slow.

Also Known As: Pro Time with INR Test, Prothrombin Time and International Normalized Ratio test, Prothrombin Time PT with INR Test, Prothrombin Time with INR Test, Prothrombin with INR, Protime with INR, PT Test

Collection Method: Blood draw

Specimen Type: Whole Blood

Test Preparation: No preparation required

When is a Prothrombin Time with INR test ordered?

When a person takes the anticoagulant medicine warfarin, a PT and INR are ordered on a regular basis to confirm that the prescription is working effectively and that the PT/INR is adequately extended. A doctor will prescribe them frequently enough to ensure that the treatment is having the desired effect, namely, boosting the person's clotting time to a therapeutic level while minimizing the danger of excessive bleeding or bruising.

When a person who isn't taking anticoagulants exhibits signs or symptoms of excessive bleeding or clotting, a PT may be ordered when they are experiencing:

• Bleeding that isn't explained or bruises that isn't easy to get rid of
• Nosebleeds
• Gums that are bleeding
• A blood clot in an artery or vein
• Disseminated intravascular coagulation
• A persistent disorder that affects hemostasis, such as severe liver disease

PT and PTT may be prescribed prior to surgery when there is a high risk of blood loss associated with the procedure and/or when the patient has a clinical history of bleeding, such as frequent or severe nosebleeds and easy bruising, which may indicate the presence of a bleeding problem.

What does a Prothrombin Time with INR blood test check for?

The prothrombin time is a test that determines a person's capacity to make blood clots properly. The international normalized ratio, or INR, is a calculation based on the results of a PT that is used to track people who are taking the blood thinner warfarin.

After chemicals are added to a person's blood sample, a PT measures how long it takes for a clot to develop. The PT is frequently used with a partial thromboplastin time to measure the number and function of proteins known as coagulation factors, which are essential for optimal blood clot formation.

When an injury develops in the body and bleeding ensues, the clotting process known as hemostasis begins. This process is aided by a series of chemical events known as the coagulation cascade, in which coagulation or "clotting" components are activated one by one, leading to the development of a clot. In order for normal clotting to occur, each coagulation factor must be present in appropriate quantities and operate effectively. Excessive bleeding can result from too little, while excessive clotting can result from too much.

There are two "pathways" that can trigger clotting in a test tube during a laboratory test, the extrinsic and intrinsic pathways. Both of these pathways subsequently converge to finish the clotting process. The PT test assesses how well all coagulation factors in the extrinsic and common routes of the coagulation cascade cooperate. Factors I, II, V, VII, and X are included. The PTT test examines the protein factors XII, XI, IX, VIII, X, V, II, and I, as well as prekallikrein and high molecular weight kininogen, which are all part of the intrinsic and common pathways. The PT and PTT examine the overall ability to generate a clot in a fair period of time, and the test results will be delayed if any of these elements are insufficient in quantity or are not operating effectively.

The PT test is normally done in seconds and the results are compared to a normal range that represents PT levels in healthy people. Because the reagents used to conduct the PT test vary from one laboratory to the next and even within the same laboratory over time, the normal ranges will change. The Internationalized Normalized Ratio, which is computed based on the PT test result, was developed and recommended for use by a World Health Organization committee to standardize results across various laboratories in the United States and around the globe for people taking the anticoagulant warfarin.

The INR is a formula that accounts for variations in PT reagents and enables for comparison of findings from different laboratories. When a PT test is performed, most laboratories report both PT and INR readings. However, the INR should only be used by people who are taking the blood thinner warfarin.

Lab tests often ordered with a Prothrombin Time with INR test:

• Partial Thromboplastin Time
• Fibrinogen Activity
• Platelet Count
• Complete Blood Count (CBC)
• Coagulation Factors
• Warfarin Sensitivity testing

Conditions where a Prothrombin Time with INR test is recommended:

• Bleeding Disorders
• Excessive Clotting Disorders
• Vitamin K Deficiency
• Liver Disease
• DIC

How does my health care provider use a Prothrombin Time with INR test?

The prothrombin time is used to diagnose the origin of unexplained bleeding or abnormal blood clots, generally in conjunction with a partial thromboplastin time. The international normalized ratio is a calculation based on the results of a PT that is used to monitor people on the blood thinner warfarin.

Coagulation factors are proteins that are involved in the body's process of forming blood clots to assist stop bleeding. When an injury occurs and bleeding begins, coagulation factors are triggered in a series of events that finally assist in the formation of a clot. In order for normal clotting to occur, each coagulation factor must be present in appropriate quantities and operate effectively. Excessive bleeding can result from too little, while excessive clotting can result from too much.

The PT and INR are used to monitor the anticoagulant warfarin's efficacy. This medication influences the coagulation cascade's function and aids in the prevention of blood clots. It is given to those who have a history of recurrent abnormal blood clotting on a long-term basis. Warfarin therapy's purpose is to strike a balance between preventing blood clots and causing excessive bleeding. This equilibrium must be carefully monitored. The INR can be used to change a person's medication dosage in order to get their PT into the ideal range for them and their condition.

What do my PT and INR test results mean?

Most laboratories report PT findings that have been corrected to the INR for persons taking warfarin. For basic "blood-thinning" needs, these persons should have an INR of 2.0 to 3.0. Some people with a high risk of blood clot require a higher INR, about 2.5 to 3.5.

The outcome of a PT test is determined by the method utilized, with results measured in seconds and compared to a normal range defined and maintained by the laboratory that administers the test. This normal range is based on the average value of healthy persons in the area, and it will differ somewhat from test to lab. Someone who isn't on warfarin would compare their PT test result to the usual range provided by the laboratory that conducted the test.

A prolonged PT indicates that the blood is taking an excessive amount of time to clot. This can be caused by liver illness, vitamin K inadequacy, or a coagulation factor shortage, among other things. The PT result is frequently combined with the PTT result to determine what condition is present.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Phosphatidylserine/Prothrombin (PS/PT) Antibodies (IgG, IgM)

Clinical Significance

Phosphatidylserine/Prothrombin (PS/PT) Antibodies (IgG, IgM) - Antiphospholipid Syndrome (APS) is an acquired autoimmune thrombophilia characterized by thrombosis (venous and/or arterial or microvascular) and/or pregnancy loss or morbidity in association with persistent positivity of a heterogenous group of autoantibodies known as anti-phospholipid antibodies (APL). 
The international laboratory consensus criteria for the diagnosis of APS includes a positive lupus anticoagulant and/or moderate to high positivity for IgG/IgM Cardiolipin and Beta-2-Glycoprotein I antibodies. Although not included in the criteria classification for APS diagnosis, antibodies directed against a phosphatidylserine/prothrombin complex (PS/PT) have been reported to have a high association with venous thrombosis and obstetric abnormalities but not with arterial thrombosis. In addition, a very high degree of concordance between the concentration of aPS/PT and lupus anticoagulant activity has been demonstrated. 

Reference Range(s)

Alternative Name(s)

PSPT IgM Antibodies,aPS/PT IgG, IgM