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Relapsing fever natural history, complications and prognosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Most cases eventually resolve spontaneously. If left untreated, during the crisis, up to 10% of patients with relapsing fever may progress to develop cerebral edema with seizures, cardiac failure, or death. Common complications of relapsing fever are iridocyclitis, meningitis, encephalitis, myocarditis, endocarditis, pneumonia, abnormal coagulation with hemorrhage, and spontaneous abortion or transplacental transmission. With early treatment, the death rate is reduced. Those who have developed coma, myocarditis, liver problems, or pneumonia are more likely to die.

Natural History

Most cases eventually resolve spontaneously. If left untreated, during the crisis up to 10% of patients with relapsing fever may progress to develop cerebral edema with seizures, cardiac failure, or death.

Complications

TBRF in pregnancy

TBRF during pregnancy can cause spontaneous abortion, [[premature birth, and neonatal death (Melkert and Stel 1991). The maternal-fetal transmission of Borrelia is believed to occur either transplacentally (Steenbarger 1982) or while traversing the birth canal. In one study, perinatal infection with TBRF was shown to lead to lower birth weights, younger gestational age, and higher perinatal mortality.

Prognosis

  • Given appropriate treatment, most patients recover within a few days. The death rate for untreated LBRF ranges from 10 – 70%. In TBRF, it is 4 -10%. With early treatment, the death rate is reduced.
  • Poor prognostic signs include severe jaundice, severe change in mental status, severe bleeding, and prolonged QT interval on ECG.

References

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