Pattern of pleural effusion in Eastern Province of Saudi Arabia: a prospective study.

In order to establish the clinical pattern and aetiology of pleural effusion in adults in the eastern province of Saudi Arabia, all patients aged 18 years and above presenting with clinical and radiological evidence of pleural effusion, between 1st December 1987 and 30th November 1991, at three participating hospitals, were prospectively studied. Of the 201 (145 male, and 56 female) patients recruited, 102 (51%) were Saudis; their mean age was 43.4 +/- 17.8 years. Pleural effusion was more common on the right side (56%) than the left (32%). In rank order, the most common diagnoses were tuberculosis (37%), neoplasm (18%), parapneumonia (14%), and congestive cardiac failure (14%). There were a variety of other causes. The aetiology was indeterminate in only 3 (1.5%) patients. Patients with tuberculosis (75 patients) were relatively young (mean age 33.4 years) and 50 (67%) of them were expatriates, mainly from the Indian subcontinent and Yemen. Of the diagnostic procedures, the most useful were histological examination and culture of pleural biopsy. The contribution of culture and cytology of pleural fluid to diagnosis was rather small. It is concluded that the clinical pattern and aetiology of pleural effusion observed in this study are similar to those of the developing countries, although they seem to have been influenced by the large migrant labour force in the country.