Clinical and epidemiological analysis of 18 cases of Japanese spotted fever in Zigui County / 中华检验医学杂志

ABSTRACT

Objective:The epidemiological and clinical characteristics of 18 cases of Japanese spotted fever (JSF) in Zigui County were analyzed in order to improve the prevention and treatment of JSF.Methods:This is a case series analysis. The epidemiological and clinical data, laboratory tests and imaging characteristics of 18 JSF cases with median age of 60 years (54, 68) identified by The People′s Hospital of Zigui from April 2021 to August 2022 were collected and analyzed retrospectively.Results:Most (17/18) of the patients were farmers and all had a field exposure history. The patient′s onset was from April to October. Spring and autumn were the seasons with the highest incidence of JSF. The first symptoms of patients were high fever, headache, and fatigue. Of the 18 cases, 15 had a rash and 12 presented an eschar and 3 had neither rash nor eschar. In addition, 10 of 18 cases experienced edema of both lower extremities, and 3 got disturbance of consciousness. Laboratory tests found that 15 patients had abnormal white blood cells and 11 patients had decreased platelets. C-reactive protein, procalcitonin, D-dimer, lactate dehydrogenase, and alpha-hydroxybutyrate dehydrogenase were elevated in all patients; 13 patients with elevated alanine aminotransferase, 14 patients with elevated aspartate transamination. Kidney damage caused by Rickettsia japonica infection showed by abnormal proteinuria in 11 of the patients. Conclusions:The most common clinical manifestations of JSF are non-specific indications such as high fever, chills, fatigue, headache. The eschar and rash, which are the main features of Rickettsia infection, are not present in all patients, resulting delay of diagnosis or misdiagnosis. Medical workers should be more alert to rickettsial infections in patients with fever of unknown origin, especially in seasons of high incidence of spotted fever. Early diagnosis and correct antibiotic treatment shall be given according to the patient′s clinical manifestations, laboratory results and imaging test to control disease progression.