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Primary HIV Infection

Acute retroviral syndrome occurs at the time the infection is acquired in 60% to 80% of HIV-infected persons. The illness resembles infectious mononucleosis from infection with Epstein-Barr virus (EBV), and acute retroviral syndrome is a consideration in differential diagnosis of heterophil-negative mononucleosis.

Clinical signs and symptoms

The period between acquisition of HIV and onset of symptoms is about 14 days, and the characteristic signs and symptoms range from a mild fever and sore throat to a severe mononucleosis-type syndrome.

In those patients with symptomatic seroconversion, the five most common signs and symptoms are fever, fatigue, pharyngitis, weight loss, and myalgias. Characteristic symptoms of acute retroviral syndrome.

Differential Diagnosis of Primary HIV Infection

Epstein-Barr virus mononucleosis Primary cytomegalovirus infection Primary herpes simplex virus infection Viral hepatitis Rubella Toxoplasmosis Secondary syphilis Measles Disseminated gonococcal infection Drug reaction

Signs and Symptoms of Primary HIV Infection
Feature	Frequency (%)
Fever Fatigue Pharyngitis Weight loss Myalgias Headache Nausea Cervical adenopathy Night sweats Diarrhea Vomiting Rash	95 90 70 68 60 58 58 55 50 50 40 35

Laboratory features

Primary HIV infection is diagnosed by a positive plasma HIV RNA obtained on the same day as a negative Western blot assay. If the interval between onset of symptoms and ordering of the HIV RNA test and Western blot assay is prolonged, both tests will be positive, suggesting that the patient has been infected with HIV.

Clinical evaluation of possible primary HIV infection often includes a heterophil antibody (Monospot) test to rule out EBV mononucleosis, cytomegalovirus antigen or antibody, acute and convalescent serologic tests for rubella and toxoplasmosis, rapid plasma reagin test, Western blot assay for herpes simplex virus, and serologic tests for hepatitis (including hepatitis C virus RNA polymerase chain reaction).

Initial management

When the diagnosis of primary HIV has been established, the patient should be examined for syphilis, herpes simplex, venereal warts, gonorrhea.

If the patient is not infected with hepatitis A or B, vaccination should be considered. If the patient was identified as HIV RNA-positive and HIV EIA-negative.

Therapy

Therapy during primary HIV infection

Viral loads are very high in the first weeks and months of HIV infection, and intervention at this time may ultimately result in a significant decrease.

The therapeutic regimen for acute HIV infection should include a combination of two nucleoside reverse transcriptase inhibitors and one potent protease inhibitor. Potential combinations of agents are much the same as those used in established infection.

Two nucleosides reverse transcriptase inhibitors plus a protease inhibitor2 NRTIs and 1 protease inhibitor.

Zidovudine ( AZT, Retrovir 300 mg PO bid) + lamivudine ( 3TC, Epivir 150 mg bid), didanosine ( ddl, Videx), or zalcitabine ( ddC, Hivid) + potent protease inhibitor ( indinavir, Crixivan 800 mg q8h) or

Stavudine ( d4T, Zerit) + lamivudine or didanosine + potent protease inhibitor

Two nucleosides plus a non-nucleoside reverse transcriptase inhibitor:

Zidovudine (AZT, Retrovir) + lamivudine, didanosine, or zalcitabine + nevirapine (Viramune) or delavirdine mesylate (Rescriptor) or

Stavudine + lamivudine or didanosine + nevirapine or delavirdine.

Triple-drug therapy may result in a significant clinical benefit when instituted as soon as possible after HIV acquisition. Once therapy is initiated it should be continued indefinitely because viremia may reappear.

Postexposure prophylaxis

Combination chemotherapy results in fewer transmissions, and use of combination chemotherapy, including a protease inhibitor, is suggested.

Postexposure prophylaxis should also be initiated

Postexposure prophylaxis treatment regimens

Zidovudine (ZDV): 300 mg PO bid and

Lamivudine (3TC, Epivir): 150 mg bid

Protease Inhibitor: Indinavir ( Crixivan) 800 mg q8h or Nelfinavir 750 mg tid (if needed to ensure 2 new antiviral drugs.