Acute Retroviral Syndrome (ARS) hidden by an Emerging Infectious Disease

BORDA, M; BLANCO S; GALLEGO S; CASTRO G; FREGA L; BARBÁS G; URFALIÁN G; CHUMACERO P; CANNA F; SICILIA P; BRACAMONTE A; KADEMIÁN S; DE LEÓN J; CUDOLÁ A

Simposio; III International Clinical Virology Symposium and Advances in Vaccines.; 2010

Introduction Clinical manifestations associated to ARS in HIV primary infection are unspecific and could be confused with emerging and re-emerging infectious diseases named as Acute Febrile Syndrome (AFS). The aim of this work was evaluate the importance to include the differential diagnosis of acute HIV infection in cases of fever of unknown origin, analyzing clinical, epidemiological and laboratory data from patients with AFS referred to Central Laboratory of Cordoba with presumptive diagnosis of Dengue, initially. Materials and Methods Between September 2009 and June 2010, at the Central Laboratory of Córdoba, 44 AFS cases were studied for HIV and Dengue. Samples were evaluated for IgM anti-Dengue (SUMA), anti-HIV antibodies and p24 antigen (BIORAD), P24 Antigen (BIOMERIEUX), Anti-HIV-1/2 antibodies (BIORAD) and Western-blot (BIOKIT). Samples with inconclusive serologic results for HIV were evaluated by NAT (CHIRON) to detect viral RNA. Clinical and epidemiological data were obtained from AFS surveillance reports. Results Three (1.32%) of the the 44 studied samples were reactive for IgM anti-Dengue and 9 (20.5%) were reactive for Ag/Ab-HIV. The 9 HIV-1 reactive samples were reactive for Ag P24 and, in the follow-up, 4 were indeterminate and 5 became positive by Wb. Three of the indeterminate samples were positive for viral RNA by NAT. While most of the patients with AFS shared the signs/symptoms evaluated, some of them as diarrhea, vomiting and rash, occurred most frequently (44.5%, 66.7% and 55.6% respectively) in patients with ARS caused by HIV. Besides, HIV infected patients showed severe leucopoenia and thrombocytopenia. Conclusions The diagnosis of HIV during the acute infection phase is missed in the majority of cases, as other viral diseases are often assumed to be the cause of the symptoms. Moreover, since there are no HIV-1-specific antibodies detectable at this early stage of infection, the diagnosis requires a high degree of clinical suspicion, based on clinical symptoms and history of exposure, in addition to specific laboratory tests. The present study highlights the importance that primary care clinicians keep in mind the suspicion of primary infection by HIV, since rarely the first appointment is addressed to the infectious disease physician.