Clinical Manual for Management of the HIV-Infected ... - myCME.com

Primary HIV Infection
Background
Primary HIV infection refers to the very early stages
of HIV infection, or the interval from initial infection
to the time that antibody to HIV is detectable. During
this stage of HIV infection, patients typically have
symptoms of acute HIV seroconversion illness, very
high HIV RNA levels of >100,000 copies/mL, and
negative or indeterminate HIV antibody tests.
The diagnosis of patients with primary HIV infection
is a clinical challenge. The symptoms of primary HIV
are nonspecific, and although many patients seek
medical care for symptoms of HIV seroconversion
illness, the diagnosis commonly is missed at initial
presentation. The difficulties involve recognizing
the clinical presentation of acute HIV infection and
testing patients appropriately. In HIV treatment
clinics, clinicians generally do not see patients with
primary HIV infection, unless they are referred with
this diagnosis already established. In other health care
settings, clinicians may not be familiar with the signs
and symptoms of acute HIV infection and often do not
consider this diagnosis.
After infection with HIV, it takes a median of 25
days before the HIV antibody test becomes positive;
in some individuals, it may be several months before
seroconversion. Individuals with known exposures to
HIV, whether occupational or not, should be monitored
closely beginning at about 3 weeks after exposure
(routine monitoring at 6 weeks, 3 months, and 6
months after exposure to HIV is likely to result in
delayed diagnosis of HIV infection). For information on
postexposure prophylaxis, see chapters Nonoccupational
Postexposure Prophylaxis and Occupational Postexposure
Prophylaxis.
S: Subjective
More than three quarters of patients who become
infected with HIV develop symptoms consistent with
primary HIV infection. Symptoms typically appear
a few days to a few weeks after exposure to HIV, and
generally include several of the following:
♦
♦
♦
Fever
Rash, often erythematous maculopapular
Fatigue
Section 1—Testing and Assessment | 1–33
♦ Pharyngitis
♦ Generalized lymphadenopathy
♦ Urticaria
♦ Myalgia/arthralgia
♦ Anorexia
♦ Mucocutaneous ulceration
♦ Headache, retroorbital pain
♦
Neurologic symptoms (eg, aseptic meningitis,
radiculitis, myelitis)
This symptomatic phase usually persists for 2-4 weeks
or less, although lymphadenopathy may last longer.
These symptoms and signs are similar to those of many
other illnesses, including other viral syndromes. To
diagnose early HIV infection, clinicians must consider
HIV in the differential diagnosis for at-risk patients
with symptoms resembling flu or mononucleosis. A
history of recent risk behaviors should be obtained from
all patients who present with symptoms consistent with
acute HIV infection.
O: Objective
During the symptomatic phase of HIV seroconversion,
the HIV antibody test is likely to be negative or
indeterminate. For patients who have symptoms
consistent with seroconversion illness and a recent
high-risk history for HIV exposure, an HIV RNA
(viral load) test should be performed, in addition to the
HIV antibody test, as part of the evaluation. Patients
with negative antibody tests but high HIV viral loads
(>100,000 copies/mL) can be considered to be infected
with HIV, although the antibody test should be
repeated later to confirm seroconversion. False-positive
HIV viral loads have been reported in approximately 5%
of patients who were tested after HIV exposures. A low
viral load (100,000 copies/mL and often
millions of copies/mL) in acute infection. Patients who
have indeterminate HIV antibody test results, low HIV
viral loads, and no clear HIV risk factors or symptoms
of primary HIV infection should have repeat antibody
testing in 4-6 weeks, without other interventions. For
patients without significant risk factors, indeterminate
results rarely indicate evolving seroconversion.