Syphilis Test VDRL

The syphilis test, VDRL is used to diagnose syphilis. The nontreponemal test is usually performed on blood but may be done on a serum sample or cerebro-spinal fluid (CSF). The test checks for an antibody that can be produced while infected with syphilis. Syphilis test VDRL is not very useful for detecting syphilis in very early or advanced stages. The test is also used to monitor patients' response to syphilis treatment. Syphilis VDRL test can result in false positive result even in the absence of infection due to recent immunization, other bacterial and viral infections and certain chronic conditions (e.g. liver disease, malignancy). Hence, a confirmatory test, the FTA-ABS test is done to check for syphilis-specific antibodies. Though no special preparation is required on the part of an individual who is to be tested, health care officials recommend abstaining from alcohol consumption 24 hours before a VDRL test.

Blood Transfusion

Blood transfusion is one of the important procedures administered in healthcare centers to meet surgical and trauma needs. This procedure is categorized under transfusion medicine section. Blood transfusion is a high-risk procedure as it involves multiple protocols and guidelines for safe and effective transfusion.

Guidelines and Procedure

Transfusion medicine has high significance as it involves the transfusion of blood and blood products depending upon the patient needs. Blood required for the transfusion is obtained from blood banks, which are established either by the government or privately following NCCLS standards for the blood banks. The standards are evaluated by organizations such as WHO to set a uniform and global protocol for safe transfusion. Blood transfusion is predominantly done to increase the percentage of hemoglobin in anemic patients and also to replace vital components such as platelets and serum proteins in some medical conditions. Other reasons for blood transfusion is to replace the amount of blood lost during surgery or trauma. Patients suffering thrombocytopenia (any disorder in which there is an abnormally low amount of platelets) might be in need of platelet transfusion.

Blood banks are authorized by the government to collect blood of different groups. Some of the rare groups include B negative, O negative and Bombay blood group. In these situations, the names and the address of these respective rare blood types are noted to ensure timely availability in case of a transfusion request. Cancer patients also require transfusion in case of conditions such as leukemia and malignant carcinomas associated with spleen or bone marrow. Leukocyte reduction procedure is followed in some transfusion centers in order to minimize the incidence of transfusion-associated allergic reactions. All donors are checked for a three-month gap before the subsequent transfusion to facilitate fresh blood collection from the donors containing viable red blood cells.

Different types of Blood transfusions:

Fresh Whole Blood: This is mostly needed during cardiac surgery or massive hemorrhage. Fresh Whole blood has RBC, plasma and fresh platelets.

Packed RBC: This is mostly needed to raise the hematocrit (the proportion of total blood volume that is composed of red blood cells).

Frozen packed RBC: Stored for nearly 3 years, frozen packed RBC is sparingly used. It is often used for rare blood groups. Patients suffering severe leukoagglutinin reactions or anaphylactic reactions might need this.

Leukocyte-Poor Blood: Patients who suffer severe leukoagglutinin reactions might need this. It is an expensive process as WBC are removed by centrifugation.

Precautions and risks

Transfusion is a very important procedure and hence primary analysis of the donor blood is done in order to avoid blood borne sepsis, transfusion allergies and organ damage. The donor blood is always cross-matched with the recipient's in order to check the compatibility of the blood. All procedures are documented to ensure safety and tracking of a transfusion procedure, as it is associated with medico-legal protocols. The A and B antigens are the first check before transfusion. In emergencies, type O/Rh-negative blood can be given to any recipient and usually packed cells are given. The Rh factor has also to be tested. Blood from the donor is also investigated for infections such as HIV 1&2, HBV, HCV, and VDRL to ensure safe transfusion.

Blood is collected from the healthy donor in a blood bank by administering venipuncture procedure from the brachial region. The obtained blood is transported for immediate need in surgeries or stored for few days in case of a scheduled surgery having the requirement for the particular blood group. The transfusion requirement is clearly stated in the surgical form and the blood bank technicians provide number of units required on the given date. Some of the common side effects associated with blood transfusions are infections of both viral and bacterial origin obtained from an infected donor. Receipt of blood contaminated with gram-negative bacteria often causes septic shock, Disseminated intravascular coagulation or DIA (a large amount of procoagulant enters the blood stream over a short period of time, overwhelming the body’s ability to replenish coagulation factors and causing bleeding) and acute kidney injury. Receipt of blood with gram-positive bacteria causes fever and Bacteremia (presence of bacteria in blood) but rarely causes sepsis.

Syphilis Test FTA-ABS

Treponema pallidum, the bacterium which causes syphilis has four subspecies:

• Treponema pallidum pallidum, which causes syphilis
  
• T. pallidum endemicum, which causes bejel or endemic syphilis
  
• T. pallidum carateum, which causes pinta
  
• T. pallidum pertenue, which causes yaws
  

To detect antibodies to Treponema pallidum, the FTA-ABS (Fluorescent treponemal antibody absorbed), a blood serum screening test is done. This is sometimes also referred to as syphilis Immunofluorescent Assay (IFA). The FTA-ABS test is a second test to confirm the presence of the infection and is usually done after the RPR test and VDRL test results are positive. FTA-ABS test is used to detect syphilis infection at any stage except during the first 3 to 4 weeks after exposure and in tertiary stages of the disease. The test is more reliable for the secondary stage of syphilis. The test is done on a sample of blood or spinal fluid. A positive FTA-ABS usually indicates infection with syphilis and a negative or nonreactive result means there is no current or past infection with syphilis. The test requires no prior preparation on the part of the individual who is to be tested.