In recent years, the decrease in reported tuberculosis in the United States has been due almost entirely to a drop in the number of cases of pulmonary disease. There has been little change in the average number of extrapulmonary cases reported. A retrospective survey of extrapulmonary tuberculosis has shown that it differs from pulmonary tuberculosis with regard to sex and race distribution, diagnosing physician's speciality and proportion of cases bacteriologically confirmed. There is variation within extrapulmonary cases according to specific anatomic site with regard to the above characteristics as well as age distribution. These epidemiologic differences in tuberculosis of different sites are unexplained.