Background: To assess the clinical, radiologic and microbiological features of lung cavitation and HIV infection. Evaluation of the differences related to this disease in the last years.
Patients and methods: Retrospective review of all patients with lung cavitation and HIV infection admitted at our hospital from January 1989 until December 1994 and prospective study of all patients with the same characteristics during 1995 and 1996. Lung cavitation was defined as any parenchymal lesion, with air content, visible in a simple X-ray and greater than 1 cm of diameter. Criteria for confirmed, probable or possible diagnosis were defined.
Results: 78 cases of lung cavitation have been identified in 73 patients. The radiologic patterns included unilobar and multilobular involvement in 31 and 47 cases, respectively. Cavities were multiple and single in 40 and 38 cases respectively. Findings with fine needle aspiration biopsy (FNAB) were diagnostic in 11 out of 14 cases. A clinical diagnosis was performed in all 78 cases, with microbiological results in 69 cases (88.5%): Mycobacterium tuberculosis in 20, Pneumocystis carinii in nine, Pseudomonas aeruginosa in nine, Staphylococcus aureus in eight (5 endocarditis with cavitary septic emboli), Rhodococcus equi in six, P. aeruginosa and S. aureus in three, Salmonella enteritidis in three, Cryptococcus neoformans in two, Aspergillus fumigatus in two and others in 7 cases. Confirmed, probable and possible diagnosis was considered in 54, 15 and 9 cases, respectively. Thirteen episodes of spontaneous pneumothorax were found.
Conclusions: The lung cavitation rate is low, compared with the number of admissions related to HIV infection; nevertheless, many of them are in close relationship with HIV infection, and most of them are caused by treatable infections. It is important to know the clinical and radiological characteristics, in order to establish an early diagnosis and an appropriate therapy. Pseudomonas aeruginosa is becoming an important cause of lung cavitation. In our series, spontaneous pneumo-thorax was not related to Pneumocystis carinii pneumonia in 61.5% of cases.