[The natural history of of the antiretrovirals: the continuum of their evaluation]. / La historia natural de los antirretrovirales: el continuum de su evaluación.

Antiretroviral drugs have, as any medical therapy, their natural history. They are born by screening or designing of molecules with activity against HIV, their efficacy and safety is investigated by clinical trials, evaluated by regulatory bodies, used by clinical practice, and finally analyzed by quality of care, economic, social and ethical studies. This flow of information is dynamically accumulated, but it may stop if negative results are obtained. The described knowledge pathway implies that specific methods are needed to answer different questions. At the same time, many decisions have to be taken in order to keep the process flowing, including multiple agents, such as drug industries, government departments, clinicians, health care providers and health policy makers. This paper describes a comprehensive conceptual framework, including the "knowledge" on antiretroviral drugs, the "methodologies" needed to generate them, and the underlying processes of "decision making". It proposes the need for a continuum of assessment of these drugs.

[Determination of antibodies against Borrelia burgdorferi in patients with morphea, lichen sclerosus et atrophicus and erythema chronicum migrans]. / Determinación de anticuerpos frente a Borrelia burgdorferi en pacientes con morfea, liquen escleroso y atrófico y eritema crónico migrans.

Several cutaneous entities described in Europe as Chronic Migrans Erythema (CME), Mild Cutis Lymphadenosis (MCL) and Chronic Atrophyc Acrodermatitis (CAA) constitute clinical manifestations of a Borrellia Burgdorferi. The presence of clinical and hystologic lesions similar to those of liquen esclerosus and atrophyc (LEA) and localized esclerodermia (morphea) in patients with CAA has driven to several authors to demonstrate the aethiologic participation of B. Burgdorferi in patients carrying those cutaneous lesions with contradictory results. A serologic study with indirect immunofluorescence (IIF) and FIAX test was performed in 16 patients (9 with morphea, 6 with LEA and 1 with CME) in order to evaluate the role of this microorganism in our environment. Five reactive sera were obtained of which only one presented IgG antibodies titrated at 1/256. The IgM antibodies by IIF and IgG by FIAX test turned out to be negative. A specific relationship between B. Burgdorferi and the studied entities could not be established.

[Drug-resistant tuberculosis at a general hospital]. / Tuberculosis resistente a fármacos en un hospital general.

OBJECTIVES: To determine the prevalence of M. tuberculosis isolates resistant to drugs in a general hospital and to assess its association with HIV infection. MATERIALS AND METHODS: Susceptibility analysis of all isolates of M. tuberculosis in a 4-year period (1990-1993). The proportion method was used to study the susceptibility to eight drugs. To assess the association of resistance with HIV infection a crossing was made of patients records who had M. tuberculosis recovered and that of patients with positive serology to HIV. RESULTS: Forty-two out of a total of 760 isolates (5.5%) were resistant to at least one drug, including isoniazid in 27 (3.3%), rifampin in 13 (1.6%), and pyrazinamide in 2 (0.2%). None of the isolates was resistant to ofloxacin. Twenty isolates (2.6%) were resistant to more than one drug and 9 (1.2%) were resistant to at least isoniazid and rifampin. Overall, 39% of resistance to one drug occurred in patients who had not received previous therapy with that drug. A greater incidence of resistant isolates was observed in HIV+ patients (7.3%) than in HIV- patients (4.6%), although this difference did not reach a statistical significance. CONCLUSIONS: Drug resistance rate in M. tuberculosis isolates in our hospital is still low and apparently not associated with HIV infection.