To summarize the clinical features, immunological and virological characteristics of HIV-1 infected patients in the acute phase for the sake of improving the understanding of acute HIV-1 infection and early diagnosis.

To retrospectively analyze the clinical manifestation and laboratory data of 25 patients with acute HIV infection, who were admitted to the Department of Infectious Diseases, Peking Union Medical College Hospital from 2006 to 2013.

Among the total 25 patients, 19(76%) patients were sexually transmitted, including 17(68%) of whom were homosexual. Twenty two (88%) patients presented significant symptoms. Common symptoms consisted of fever (15 patients, 60%), cervical lymphoadenopathy (8 patients, 32%), skin rashes (6 patients, 24%), diarrhea (5 patients, 20%), shortness of breath (3 patients, 12%), sore throat (3 patients, 12%), and cough (3 patients, 12%), while only one case represented as Guillain-Barr syndrome, upper arm cellulitis, headache and vomiting, and perianal abscess. Laboratory examination indicated elevated peripheral lymphocytes (13 patients, 52%), abnormal liver function (11 patients, 44%), thrombocytopenia (1 patients, 4%). Notably, 2 patients(8%) revealed negative results of HIV antibody, who were diagnosed with positive plasma viral load. The average viral load was (4.68±0.83) lg copies/ml. CD₄⁺ T cell count was 473(343, 621)cells/μl. CD₈⁺ T cell count was 1 296(997, 2 177)cells/μl with maximal value of 7 984 cells/μl. The CD₄/CD₈ ratio was 0.33(0.22, 0.53)including 24 (96%) patients with obvious inverted ratio. The positive rates of immune activation markers HLA-DR and CD₃₈ on the surface of CD₈⁺ T cells were (74.9±16.1)% and (84.9±12.5)% respectively. The viral load had a significant positive correlation with the expression of HLA-DR and CD₃₈.

The most common symptoms of acute HIV-1 infection are fever, cervical lymphadenopathy, skin rashes and diarrhea. Significantly elevated CD₈⁺ T cell count, inverted CD₄/CD₈ ratio and abnormal immune activation markers contribute to the early diagnosis of acute HIV infection.

HIV-1; Acute infection; Clinical manifestation