Case Report Successful Detection of Unrecognized Rickettsia typhi in Pregnancy Using Cell-Free Next-Generation Sequencing

摘要: 1. BackgroundMurine typhus is a Rickettsial disease caused by the bacteria Rickettsia typhi (R. typhi) or possibly R. felis and can be transmitted by infected fleas harbored by rats, cats, dogs, and other small mammals [1–5]. In the United States, Texas reports the highest numbers of flea-borne typhus cases annually with the majority of cases occurring in the southern coastal region [2–5]. In 2018, there were 738 reported cases in the state of Texas, representing a 2-fold increase compared to 2016 [1]. Clinical presentation often includes fever, headache, rash, nausea, vomiting, and myalgias accompanied by abnormal hematologic indices including anemia (18–75%), thrombocytopenia (19–48%), elevated aminotransferase levels (38–90%), and an elevated erythrocyte sedimentation rate (59–89%)[3–5]. Approximately 14-28% of infected people have evidence of hepatomegaly or splenomegaly, and in severe cases, pulmonary and cardiac compromise can occur [2–5]. Several case reports and series of murine typhus infection in pregnant women have been published with varying reports of adverse perinatal outcomes, ranging from a mild self-limited disease course to a 40% incidence of preterm birth and low birth weight [6–18]. This current report would total the number of published cases reported in pregnancy to 100 and is only the second published case report of murine typhus infection during pregnancy in women living in the southwestern region of the United States [6–18]. Diagnosis in pregnancy is often challenging given the overlap of initial hematologic results with other infectious diseases and critical obstetrical conditions that are more …