Fever in HIV-infected patients

Fever in HIV-infected patients
Background
Fever was a frequent sign of disease in HIV-patients in the era before the availability of antiretroviral therapy (Sepkowitz, Arch Intern Med 1993). In the natural course of HIV-infection fever can occur at initial acquisition of the virus(as part of a primo-infection), until the terminal AIDS-stage (caused by opportunistic infections, by medication prescribed as prevention or treatment of opportunistic infections, by malignancy and by of non-HIV-related conditions) (Florence, Acta clinica Belgica 2002). Fever was mainly caused by infections and malignancies. Causes of fever in a series of 108 episodes of fever in advanced HIV-patients before the use of  antiretroviral medication was widely spread werd: PCP 16 (15%), MAC 13 (12%), catheter-related bacteremia 11 (10%), bacterial pneumonia and bronchitis 11 (10%), drug-related fever 7 (6%), Non-Hodgkin Lymphoma 6 (6%), sinusitis 6 (6%), Toxoplasmosis 4 (4%), others 20 (19%) and no certain diagnosis 14 (13%).
A subgroup of patients with HIV has Fever of Unknown Origin (FUO). Criteria for this are: body temperature over 38.3°C ánd fever for more than 4 weeks for outpatients or for more than 3 days for hospitalized patients ánd confirmed HIV-infection ánd diagnosis uncertain after at least 3 days of investigation (including negative cultures after at least 2 days of microbacterial cultures). Causes of FUO in HIV-patients as combined from published series in literature (from a total of 461 episodes) are: tuberculosis 31%, MAC 15%, leishmania 8%, Non-Hodgkin Lymphoma 6%, PCP 6%, other 23% and no diagnosis 11%.
Since the availability of antiretroviral therapy the incidence of opportunistic infections had decreased by 50 to 80% (Palella, NEJM 1998). Other causes of fever became more important or were documented for the first time: fever because of medication intake,immune-reconstitution and malignancies. There is hardly any data concerning incidence and etiology of fever or FUO in HIV-patients since the introduction of antiretroviral therapy, although there are some arguments for a decreased incidence of FUO and a tendency to change in spectrum (Lozano, Eur J Clin Microbiol Infect Dis 2002).
Serum procalcitonine is produceced in the C-cells of the thyroid. It is considered by some as a more specific marker for bacterial infections. De value of this in the differential diagnosis of inflammatory conditions was studied in various clinical situations. The data concerning the value of procalcitonine in the differential diagnosis of opportunistic conditions in HIV-patients are very limited(Gérard, J Infect 1997, Schleicher, Eur Respir J. 2005)
Objectives
The objectives of this scientific work are:
- to determine the incidence of reported fever, documented fever and objective fever in the population of HIV-patients followed in the UZ Leuven and to determine this incidence in subpopulations based on sex, age, immunity as measured by last absolute T4 lymphocytes category, nadir T4 lymphocytes category, HIVviral load category, use of antiretroviral therapy or not; to determinerisk factors for fever in the whole population and in subpopulations; to determine the spectrum of etiologies causing fever in HIV-patients.
- to measure the consequences of fever in terms of doctor visits, hospitalizations, medication use, antibiotic use.
- to measure the incidence of FUO in HIV-patients; to determine the spectrum of etiologies of FUO in HIV-patients
- to evaluate and optimize the diagnostic strategy in HIV-patients with objective fever