Mortality in high risk patients with tick-borne relapsing fever analysed by the Borrelia-index

Clinical findings on 25 patients with a high spirochaetemia are presented. The diagnosis was established by demonstration of Borrelia spirochaetes in the thick blood smear and a Borrelia-index was estimated to calculate the density of the spirochaetemia. Causes of death were septicaemia (3x), severe spirochaetemia in a neonate (1x), and successive relapses in complicated cases without adequate treatment (2x). The results show a positive correlation between the degree of spirochaetemia and severity of complications and the Borrelia-index shows to have a prognostic value.