Efficacy of Oral Doxycycline versus Intravenous Doxycycline for the Treatment of Uncomplicated Scrub Typhus in Children: A Prospective Interventional Study

Abstract

Introduction: Orientia tsutsugamushi causes acute febrile illness known as scrub typhus, which is spread by the bite of the trombiculid mite. Doxycycline is the first-line treatment for clinically diagnosed cases of scrub typhus. If not diagnosed and treated early, it can lead to complications such as acute renal failure, meningoencephalitis, gastrointestinal bleeding, and multiple organ failure. However, there have been no trials comparing the effectiveness of oral and Intravenous (i.v.) doxycycline for scrub typhus treatment. Aim: To assess the efficacy of intravenous versus oral doxycycline in managing uncomplicated scrub typhus. Materials and Methods: This prospective interventional research was conducted in the Paediatrics Department at Maharajah’s Institute of Medical Sciences, Vizianagaram, India, from June 2021 to July 2022. Out of a total of 178 children diagnosed with scrub typhus during the study period, 102 children who received either oral or intravenous doxycycline as monotherapy were included. The primary outcome measures studied were the incidence of delayed defervescence and the time of defervescence. The t-test or Mann-Whitney test was applied for continuous data, and the Chi-square test or Fischer’s-exact test was used to compare dichotomous variables. Results: The mean age of children treated with oral doxycycline was 9.5±2.7 years and with i.v. doxycycline was 8.2±2.4 years. Among the 178 children diagnosed with scrub typhus, 102 (57.3%) children treated with doxycycline alone were included in the study. Out of these, 78 (76.4%) cases received oral doxycycline, while 28 (27.4%) cases received intravenous doxycycline. There was no statistically significant difference in the response rate between the two groups. The p-value for time to defervescence was 0.672, and the p-value for the incidence of delayed defervescence was 0.9845. Conclusion: Both oral and intravenous forms of doxycycline demonstrated similar efficacy in the treatment of scrub typhus. Nearly all children in both groups became afebrile within 72 hours after starting treatment.