Transcript why? (1)

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 cellregulatory 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
concurrently with zidovudine May be useful.
.
Evaluation of
asymptomatic
HTLV-I and HTLVII 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