To analyze whether a characteristic pattern distinguishes acute forms (symptoms starting no more than one week earlier) and subacute or chronic forms (symptoms lasting more than one week) of pleural tuberculosis (PT) in our practice. Retrospective analysis of 102 cases of PT diagnosed between 1986 and 1992, comparing the findings of case histories, imaging, pleural biochemistry and cytology, microbiology of sputum, pleural biopsy and fluid, anatomy and pathology studies of the biopsy specimens, course of disease, response to treatment and sequelae after one year and a half. Thirty-two patients (31.4%) had acute PT and 70 (68.6%) had chronic forms. LDH levels and the percentage of pleural nuclear polymorphism were higher in acute cases, while the concurrence of systemic involvement and lymphocytic predominance was more often seen in chronic cases. Other data analyzed were similar in both groups. No specific clinical or X-ray profiles or differences in course of disease and response to treatment distinguishes between acute and chronic forms of PT after 7 days. Only LDH levels and cytology results differentiated acute forms and, occasionally, such cases were indistinguishable from pneumonia-like effusion.