BACKGROUND Any atypical psychiatric disorder, especially if associated with somatic manifestations and when any psychiatric antecedents are missing, should lead to search for an organic pathology, and notably a Human Immunodeficiency Virus (HIV) infection. In the case of Primary Human Immunodeficiency Virus Infection (PHI), which is often symptomatic, the diagnosis is seldom made, probably because of atypical or non specific manifestations. Therefore, it is essential to consider such a diagnosis, because it may have important clinical and public health consequences (stopping the contamination chain). METHODS We present the case of a 38 year-old homosexual man from West Indies, in whom the diagnosis of PHI had been made on the basis of psychiatric symptoms evoking a Major Depressive Episode with a doubt on the presence of psychotic symptoms. To our knowledge, this is the first report of psychiatric PHI found in scientific literature. Clinical presentation was atypical: the patient had no psychiatric history (except probably a schizotypical personality, according to his family), symptoms were atypical (sudden onset and fast improvement) associated with somatic symptoms (fever, headache, sound intolerance), the latter possibly due to a meningo-encephalitis, which had been underestimated and attributed to dehydration in a period when France was faced with an important and unexpected heatwave. Blood samples were performed on admission and revealed a thrombopenia and presence of HIV P24 antigen, testifying a contamination by HIV 2 to 4 weeks earlier, this possibility having been confirmed by the patient. Further analyses found a Western-Blot partially positive test and an HIV viral load of 315 711 Eq copies/mL. CONCLUSIONS The main question about this report is the primary or secondary nature of psychiatric symptoms towards HIV infection, given that in this patient mood alteration could have possibly occurred, before HIV contamination, due to particularities of his personal and professional life. We can also question whether the neurological manifestations of PHI might be changed by a schizotypical personality. Further reports are required to answer these questions.