Erythema migrans in patients with post-traumatic splenectomy

Information on asplenic Lyme borreliosis (LB) patients with erythema migrans (EM) is lacking. We compared the course and outcome of 26 EM episodes in 24 post-trauma splenectomized patients (median age 51 years) diagnosed at a single clinical center in Slovenia during 1994–2023 with those of 52 age- and sex-matched patients with EM but with no history of splenectomy. All patients were followed for one year. A comparison of pre-treatment characteristics revealed that EM in splenectomized patients was of shorter duration before diagnosis (4 vs. 8 days, p = 0.034) with a smaller EM diameter (10.5 vs. 14 cm, p = 0.046), and more frequently fulfilled criteria for disseminated LB (3/26, 11.5% vs. 0%, p = 0.034). Treatment failure occurred in 5/26 (19.2%) EM episodes in splenectomized patients versus 0/52 in non-splenectomized patients (p = 0.003). The five treatment failure cases were retreated with antibiotic regimens used to treat EM and had complete resolution of all symptoms/signs. In conclusion, our study showed that splenectomized adult patients with EM differ somewhat in presentation and more often have treatment failure compared with non-splenectomized patients with EM.