Spirochetemia—the presence of spirochetes in the blood commonly arises from infections caused by Borrelia, Leptospira, or Treponema genera. Infections with Borrelia or Leptospiral genera require a higher index of suspicion as the symptoms as well as laboratory testing are often nonspecific. Relapsing fever in particular can be missed if the patient presents during the remission phase.
A 55-year-old male with no significant medical history presented as an inter-hospital transfer with fevers, chills, muscle cramps, fatigue and abdominal pain. Four days prior, he presented to an urgent care facility near his residence in Northeast Arizona for the same symptoms, and was discharged on naproxen after a presumed diagnosis of viral illness. The patient reported improvement over the next three days until he suddenly fell ill again, this time complaining of fevers, chills, weakness, diffuse myalgias, severe headache and photophobia. He again presented to the same urgent care facility and a CBC revealed severe thrombocytopenia and bandemia meeting 2/3 criteria of hantavirus. The patient was air-lifted to our intensive care unit with concern for Hantavirus cardiopulmonary syndrome.
Upon transfer, the patient was found to have heart rate of 104. Initial laboratory studies showed a white blood cell count of 16.9 x103/µl, platelets of 17 x 109/L (from 200 x 109/L on initial presentation) a creatinine of 1.74 mg/dl, total bilirubin of 3.5mg/dl with direct of 2.1mg/dl, alkaline phosphatase of 316 units/L. Chest X-ray and abdominal ultrasound were normal. Peripheral blood smear revealed thrombocytopenia, a left shift with toxic granulation, and numerous circulating spirochetes. Further workup including a Hantavirus IgM/IgG antibody, HIV 1/2 antibody, Treponema pallidum antibody, blood cultures, Leptospira IgM antibody, Leptospira urine culture, and Borrelia hermsii IgG/IgM antibodies were all negative.
Discussion:
Our case demonstrates the importance of clinical history and exam findings in identifying spirochete infections. The diagnosis is difficult to make, and may have been easily missed were it not for the profound number of spirochetes appearing on peripheral smear. We concluded that this case was most likely a case of relapsing fever given the typical presentation of initial febrile illness followed by a period of wellness, and then a subsequent relapse. Borrelia is extremely difficult to isolate but can best be identified using a DNA polymerase chain reaction (PCR) test which is not typically available. Doxycycline is the antibiotic of choice, and it is important to initiate if there is suspicion of relapsing fever
Conclusions:
Upon discovery of the spirochetes, the patient was started on oral doxycycline with continuous infusion of penicillin G. His clinical symptoms resolved and he discharged 3 days later to complete a ten day course of Doxycycline.