Transplantation and Immunosuppression

Immunocompromised patients have an immune system that is unable to mount a full immune response to pathogens, such as viruses, fungi, or bacteria, or toxins and tissue damage. Immunocompromised patients may include transplant patients, patients with autoimmune disorders, preterm infants, HIV-infected patients, and cancer patients. Immunosuppression can be a result of drug therapy with agents that inhibit components of the immune system;(transplant recipients are an example of this type of immunocompromised patient).

Patients who receive a solid organ transplant or hematopoietic stem cell transplant (HSTC) are started on a regimen of immunosuppressive drugs and must typically continue this therapy for the remainder of their lives. This is necessary so the donated organ, referred to as the graft, is not rejected by the recipient. The body recognizes the graft as "foreign" and will attack the graft if full immune system function is present. Organ rejection, if left untreated, can result in complete loss of the donated organ. In the case of (HSCT), the grafted stem cells will sometimes attack the recipient. This is referred to as graft versus host disease (GVHD). GVHD is a very serious complication of HSCT that compromises the success of the transplant and can often lower the long-term survival rate of these patients.

Immunosuppressive drugs can help prevent GVHD and rejection; however, if a patient's level of immune suppression is too great, they are at risk of infection from common pathogens, including viruses, bacteria, fungi, and protozoa. Therefore, physicians must constantly balance the patient's risk of infection by suppressing the immune system too much, with the patient's risk of graft rejection by not suppressing the immune system enough. To complicate the issue, episodes of rejection often mimic symptoms of infection. Consequently, testing for active infections is often necessary, as proper treatment depends upon an accurate and timely diagnosis. If an active infection is present, specific treatment is administered and immunosuppressive drugs are decreased to allow the immune system to fight the infection. Patients may successfully clear the infection without endangering the graft or rejection might begin prior to clearing the infection, in which immunosuppressive drugs must be increased to prevent complete graft rejection - a cycle that may continue depending upon the patient and type and severity of infection.

Viracor-IBT's immunological and infectious disease testing helps to improve transplant patient outcomes by providing clinicians a global view of patients’ immune status, inflammatory response, and potential infectious complications. Our extensive immunology menu enables clinicians to assess the immunological condition of their patients through a range of tactics, including assessment of B-cell and T-cell development and function, complement and lymphocyte analysis, and measurement of cytokines involved in the inflammatory process. Coupled with our post-transplant infectious disease monitoring and detection, resistance assessment and pathogen characterization, clinicians are able to optimize treatment plans to help mitigate the risk of serious complications such as rejection, GVHD, and infection.