Treatment Evaluation of HTLV infection

treatment of asymptomatic HTLV carriers is not indicated.

why? (1) Although drugs such as zidovudine and lamivudine, have long been recognized to have activity against HTLV in vitro, there is little clinical evidence of their efficacy in vivo.

(2) the asymptomatic nature of HTLV-I and -II and the low penetrance of HTLV diseases

(3) the exact role of HTLV-I in disease pathogenesis has not been clearly defined

In ATL, active viral replication does not appear to play a role in established malignant disease and tumor cells harbor oncogenic mutations in cell- regulatory genes that may not be reversible by treating the virus.

In ATL Substantial improvements in therapy have been achieved with newer regimens combining zidovudine and interferon-a. this combination produces a high rate of complete responses and prolongs survival.

HAM with its high viral load would appear to be a better candidate for antiviral treatment.

A combination of zidovudine and lamivudine was used in a clinical trial of HAM treatment, but no clinical improvement was seen. recently, interferon-a and interferon-b1a. have shown some clinical benefit. In HAM Experimental studies, such as the use of anti-TAC antibodies May be useful. concurrently with zidovudine.

Evaluation of asymptomatic HTLV-I and HTLV- II carriers.

The first step is to confirm HTLV infection, either by review of positive screening EIA and confirmatory tests or by submission of another specimen

The second step Typing of the infection as HTLV-I or HTLV-II is important because of the different disease outcomes associated with the two viral types. This can be done either by type-specific WB or immunoassay, or PCR.

The third step A clinical history regarding risk factors for HTLV Infection It is important in establishing the pretest probability infection and can be helpful in typing the infection -Familial or sexual contact with people from HTLV-I endemic areas favors that infection -a history of injection drug use or sex with an injection drug user is more consistent with HTLV-II infection.

The fourth step Medical history should elicit symptoms of neurologic disease or leukemia, (lymphoma),. Physical examination is directed at the skin, lymph nodes, and neurologic system to detect manifestations of HTLV dermatitis, ATL, or HAM.

The fifth step Laboratory evaluation may be limited to a complete blood count.

Whereas increases in the absolute lymphocyte and platelet counts have been described in prospective studies of HTLV-I and -II carriers, there is no indication that these have clinical significance. It is more important to rule out subclinical leukemia by a normal lymphocyte count and absence of flower cell morphology.

Asymptomatic seropositive patients should be followed by their primary care or infectious disease physician with annual to biannual return visits.

In general, asymptomatic carriers or those with nonspecific symptoms should be reassured by reminding them of the low penetrance of hematologic and neurologic disease.

Attention should be devoted to counseling regarding the prevention of further HTLV transmission