Human immunodeficiency virus (HIV) 2 is a human lentivirus, which shares 40% to 50% genetic homology with HIV-1, but has distinct epidemiologic, biological, and clinical features.1 First described in Senegal in 1985, HIV-2 is endemic in many west African countries, but is uncommonly found outside of that region. Human immunodeficiency virus 2 has been reported in European countries and in North America. In the United States, less than 100 cases have been reported to the Centers for Disease Control and Prevention.2 We describe a man whose ophthalmic manifestations led to a diagnosis of HIV-2 infection.
A 42-year-old African man from Burkina Faso who immigrated to the United States 8 years earlier was referred to the Retina Clinic at the University of Wisconsin–Madison after a retinal abnormality was discovered on routine examination. He had no visual complaints. His medical history was significant for a recent respiratory tract infection, with a cough treated with antibiotics on an outpatient basis.
On examination, his visual acuity was 20/20 OU. The anterior segment examination results were normal. The funduscopic examination revealed several cotton-wool spots and intraretinal hemorrhages in the posterior pole of the right eye. In the left eye, there was a small cotton-wool spot in the posterior pole and a blot hemorrhage in the temporal periphery. On further questioning, he denied any risk factors for systemic vascular disease, including a history of hypertension, diabetes mellitus, hematological disorders, collagen vascular diseases, cardiac abnormalities, constitutional symptoms, and HIV risk factors.3
Laboratory testing revealed anemia, lymphopenia, neutropenia, and renal failure. The patient had not been initially tested for HIV because of his denial of risk factors. The patient consented to HIV testing on a review of the laboratory abnormalities. Serologic testing for HIV demonstrated a reactive HIV-1/HIV-2 combined enzyme immunoassay result and an indeterminate HIV-1 Western blot analysis result. The CD4 lymphocyte count was markedly decreased at 5/µL, and the HIV-1 viral load was undetectable. A diagnosis of HIV-2 infection was made based on positive specific HIV-2 enzyme immunoassay and Western blot analysis results. On review of risk factors for HIV, after the diagnosis of HIV-2, the patient admitted to having multiple heterosexual partners in Burkina Faso before moving to the United States.
The clinical course of HIV-2 is characterized by progressive CD4 lymphocyte depletion, which occurs at a slower rate compared with HIV-1. With advancing immunosuppression, the pattern of symptoms and opportunistic illnesses are quite similar for HIV-1 and HIV-2.4 Although patients with HIV-2 infection appear to have less infectious retinopathy than patients with HIV-1 infection, the studies regarding HIV-2 and the eye are limited. In the only reported series,5 to our knowledge, patients with HIV-2 infection had no evidence of cytomegalovirus retinitis or varicella zoster infection. In this small study,5 the predominant ocular pathological feature was noninfectious retinopathy, seen in 5 (14%) of 37 patients.
Risk factors for HIV-2 infection are analogous to those for HIV-1, with sexual contact as the predominant means of transmission (Table 1).4 Since 1992, US blood banks have screened all blood products with a combination HIV-1/HIV-2 enzyme immunoassay.2 No transfusion-acquired cases of HIV-2 have been reported in the United States. Coinfection with HIV-1 and HIV-2 has been described; however, there is evidence that HIV-2 infection may decrease the risk of subsequent HIV-1 infection.4
Serologic testing for HIV-2 is readily available through most HIV testing centers and state and local health departments. Many commercially available HIV test kits combine assays for HIV-1 and HIV-2. If the combined assay is reactive, HIV-1 Western blot testing is performed. If the HIV-1 Western blot analysis result is either negative or indeterminate, a specific HIV-2 enzyme immunoassay is performed on the same sample; and if reactive, is then followed by a specific HIV-2 Western blot assay to establish the diagnosis. Human immunodeficiency virus 2 synthetic peptide testing is also available through the Centers for Disease Control and Prevention in cases in which the serologic results are less clear.
Human immunodeficiency virus is a well-recognized risk factor for vascular retinopathy. Human immunodeficiency virus 2 remains a rare disease in the United States but must be considered in at-risk individuals. Our case serves to increase awareness of HIV-2 infection, and indicates the epidemiologic features that should prompt HIV-2 testing (Table 1).
Reprints: Justin L. Gottlieb, MD, 2870 University Ave, Suite 206, Madison, WI 53705 (e-mail: firstname.lastname@example.org).
Handwerger BA, Urban AW, Gottlieb JL. Retinopathy as the Initial Presentation of Human Immunodeficiency Virus 2 Infection. Arch Ophthalmol. 2000;118(12):1695-1696. doi: