Quiz Answer

Acute retroviral (or HIV) syndrome—The diagnosis of acute retroviral syndrome was made based on results of an HIV polymerase chain reaction test, which showed more than 500,000 copies/mL of plasma HIV-RNA.

The initial manifestation of HIV infection in one half to two thirds of patients is a mononucleosis-like illness, referred to as acute retroviral syndrome, also known as acute HIV syndrome. The precise incidence of acute retroviral syndrome is not known but is reported to range from 40% to 90%.¹ The clinical features of this syndrome are nonspecific and variable; these include fever, lymphadenopathy, pharyngitis, and rash in about 70% to 90% of patients.² Additional presentations include headache, photophobia, and meningitis in about 12% of patients.² About two thirds of patients may have a truncal exanthem that may be maculopapular, roseolalike, or urticarial. Skin biopsies are nonspecific, revealing perivascular lymphocytic infiltrates and dermal mononuclear cell infiltrates.

Physical examination often demonstrates cervical, occipital, or axillary lymphadenopathy; rash; and, less often, hepatosplenomegaly. The symptoms generally resolve within 10 to 15 days but can last longer. Diagnosis can be established by the demonstration of anti-HIV antibodies (usually after 2 weeks of primary infection) by using an enzyme immunoassay (EIA). The sensitivity of an EIA is very high (about 99.5%) but the specificity is low. Western blot antibody test is the confirmatory test. Plasma HIV-1 RNA (b-DNA) levels can be used to diagnose acute retroviral syndrome before the development of anti-HIV antibodies, but the preferred and more sensitive method is viral load testing.³

Primary Epstein-Barr viral infection, also known as infectious mononucleosis, may have a presentation similar to acute retroviral syndrome, with features such as fever, sore throat, malaise, lymphadenopathy, and morbilliform or papular rash usually seen on the arms or trunk. Liver function tests are abnormal in more than 90% of cases.⁴ The heterophile antibody test and the antibody test specific to this infection are positive in the majority of patients.⁴

Secondary syphilis is characterized by nonspecific systemic symptoms, including fever; sore throat; malaise; myalgias; discrete, reddish, symmetric papular rash, with a predilection for the palms and soles. Rapid plasma regain test and venereal disease research laboratory test are positive nearly 100% of the time in secondary syphilis.³

Rocky Mountain spotted fever characteristically involves a rash that begins on wrists, forearms, and ankles, and slightly later on the palms and soles. Within 6 to 18 hours, the rash spreads centripetally to the arms, thighs, trunk, and face. The diagnosis can be confirmed with serologies.⁴

References

1. Kahn JO, Walker BD. Acute human immunodeficiency virus type 1 infection. N Engl J Med. 1998;339:33-39.
2. Kassutto S, Rosenberg ES. Primary HIV type 1 infection. Clin Infect Dis. 2004;38:1447-1453.
3. Mandell GL, Bennett JE, Dolin R, eds. General clinical manifestations of human immunodeficiency virus infection. In: Mandell, Douglas, and Bennett?s Principles & Practice of Infectious Diseases. 5th ed. Philadelphia, Pa: Churchill Livingstone; 2005:1404-1405.
4. Kasper DL, Braunwald E, Fauci AS, et al, eds. Rickettsial infections. In: Harrison?s Manual of Medicine. 16th ed. New York, NY: McGraw- Hill; 2005:510-512.