Case Presentation:
A 66 year-old man presented with fever, chills, and a diffuse erythematous truncal rash for five days. His symptoms began upon returning from travelling to Morocco and Thailand, and six weeks after a hiking trip in the Northeast. He had not received any prophylactic vaccinations or antimalarial agents. He denied sick contacts, new sexual partners or animal exposure. On admission, he was febrile, had confluent erythematous patches on his trunk and back as well as numerous petechiae on his lower extremities bilaterally. Labs were significant for thrombocytopenia, leukopenia, and transaminitis. He initially received one dose of ceftriaxone. Peripheral blood smears ruled out malaria and babesiosis. Serologies for other infectious agents were sent.
The patient remained febrile with worsening thrombocytopenia prompting the continuation of ceftriaxone to cover for typhoid fever and the initiation of doxycycline to address a possible tick-borne etiology. The patient defervesced with normalizing white cell count and stabilizing platelets. He was discharged on a 10-day course of doxycycline with close follow-up. He was not provided with coverage for typhoid given negative culture data. After the patient was discharged, dengue virus IgM & IgG serologies returned positive and Salmonella bareilly grew from the stool culture. Doxycycline was discontinued and no treatment for Salmonella was provided as it was an improbable cause of the patient’s symptoms
Discussion:
Febrile illnesses in returning travelers often represent a diagnostic quandary for hospitalists given their non-specific clinical findings and numerous lab abnormalities. Furthermore, as most serologic data are delayed several days to weeks, physicians must be particularly astute in choosing empiric therapy.
Our patient’s summertime hiking trip in the Northeast placed him at high risk for exposure to tick-borne diseases. As his symptoms occurred over 5 weeks after his potential tick exposure, he was outside of the typical incubation periods. Nevertheless, given his fairly classic presentation for a tick-borne illness coverage was warranted. His history of recent travel to Thailand placed him directly within the incubation period for various arthropod, food and water-borne pathogens. Many of these pathogens were ruled out early in the patient’s course, however typhoid fever remained a possibility and therefore empiric coverage was continued for several days while awaiting culture results. Ultimately, the patient’s symptoms were clearly the result of dengue fever and the positive stool culture for Salmonella bareilly was unlikely to have been clinically significant.
Conclusions:
Obtaining a detailed travel history is a critical aspect of hospitalist medicine with the growth of international travel and global epidemics. Maintaining a broad differential and empirically treating is key in these patients as there is often exposure to pathogens with overlapping clinical presentations.