Human T-Lymphotropic Virus Testing

General

Synonym/Acronym:
HTLV-I/HTLV-II.

Rationale
To test the blood for the presence of antibodies that would indicate past or current human T-lymphocyte virus (HTLV) infection. Helpful in diagnosing certain types of leukemia.

Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings
(Method: Enzyme immunoassay) Negative (indicating absence of HTLV).

Critical Findings and Potential Interventions
N/A

Overview

(Study type: Blood collected in a red-top tube; related body system: Circulatory/hematopoietic and immune systems.)

Human T-lymphotropic virus type I (HTLV-I) and type II (HTLV-II) are two closely related retroviruses known to remain latent for extended periods before becoming reactive. The viruses are transmitted by sexual contact, contact with blood, placental transfer from biological mother to fetus, or ingestion of human milk from an infected person. As with HIV-1 and HIV-2, HTLV targets the T4 lymphocytes. HTLV-I has been associated with adult T-cell leukemia/lymphoma (ATL) and myelopathy/tropical spastic paraparesis (HAM/TSP). Although it is believed HTLV-II may affect the immune system, it has not been associated clearly with any particular disease or condition. Retrospective studies demonstrated that a small percentage of transfusion recipients became infected by HTLV-positive blood. The results of this study led to a requirement that all donated blood units be tested for HTLV-I/HTLV-II before release for transfusion.

Indications

  • Distinguish HTLV-I/HTLV-II infection from spastic myelopathy.
  • Establish HTLV-I as the causative organism in adult lymphoblastic (T-cell) leukemia.
  • Evaluate donated blood units before transfusion.
  • Evaluate HTLV-II as a contributing cause of chronic neuromuscular disease.

Interfering Factors

N/A

Potential Medical Diagnosis: Clinical Significance of Results

Positive Findings In:

  • HTLV-I/HTLV-II infection

Nursing Implications, Nursing Process, Clinical Judgement

Before the Study: Planning and Implementation


Teaching the Patient What to Expect

  • Explain that a blood sample is needed for the test.
  • Discuss how this test can assist with indicating a past or present HTLV infection.
  • Warn that false-positive results occur and that the absence of antibody does not guarantee absence of infection, because the virus may be latent or not have produced detectable antibody at the time of testing. Advise that subsequent retesting may be necessary.

After the Study: Implementation & Evaluation Potential Nursing Actions


Treatment Considerations

  • Interventions/actions include the following: Discuss the implications of positive test results on the patient’s lifestyle. Be supportive of impaired activity related to weakness, perceived loss of independence, and fear of shortened life expectancy. Encourage and facilitate access to counseling services. Explain that the presence of HTLV-I/HTLV-II antibodies precludes blood donation but does not mean that leukemia or a neurological disorder is present or will develop.

Clinical Judgement

  • Consider the best way to explain the clinical implications of the test results.

Followup Evaluation and Desired Outcomes

  • Understands the risk of transmission and importance of proper prophylaxis.
  • Recognizes the value of strict adherence to the treatment regimen and collaboration with a pharmacist.
  • Adheres to the recommended treatment plan and individualized therapeutic interventions.

Human T-Lymphotropic Virus Testingis the Nursing Central Word of the day!