Our findings suggest that ampicillin and cloxacillin would be an inappropriate empiric therapy, if given in a nonselective fashion to these patients, since nearly 16% of isolated organisms were resistant to these drugs. The resistant organisms that we identified are commonly associated with nosocomial infections. This could explain the substantial proportion of more resistant organisms, such as staphylococci and enteric Gram-negative bacilli.
Therapy for thoracic empyema in the general population requires appropriate antibiotics, prompt drainage of the infected pleural cavity, and lung reexpansion. In HIV-infected patients, the treatment should be as in other patient groups. For a small number of HIV-positive cases with empyema, minimally invasive methods have been employed, with a success rate similar to that found in our series.
In our experience, the prevalence of the thoracic empyema in HIV-infected patients was low (5.4%) and particularly frequent among IDUs. In these patients, the empyema either preceded a diagnosis of HIV infection or was the primary cause of hospital admission. The identified organisms differed from the bacterial pathogens isolated in community pneumonia. Factors other than HIV such as drug abuse or poor nutrition may increase host susceptibility to these organisms. Because of the large number of potential pathogens, an aggressive diagnostic approach is warranted to establish a specific diagnosis, thus aiding direct therapy. An AIDS diagnosis was present in 43%, but this did not influence a patient’s final outcome.
We believe that the best approach to treatment would be an immediate administration of closed thoracostomy and a prompt administration of appropriate antibiotics, just as in other patient groups. This treatment was found to have a high success rate and a low morbidity and mortality rate in our series.