Dengue in a Recent Caribbean Traveler

“Dengue typically presents with non-specific symptoms including fever, rash, myalgias, arthralgias, headache, eye pain, nausea, vomiting…”

CASE

A 68-year-old male with history of non-insulin dependent diabetes mellitus, hypertension, and hyperlipidemia presented to the emergency department with four days of fever, malaise, fatigue, myalgias, arthralgias, nausea, poor appetite, and intermittent, mild headache. He reported extreme generalized weakness and body aches, to the point of having difficulty getting out of bed and caring for himself. He denied neck pain or stiffness, eye pain, rashes, abdominal pain, mucosal bleeding, chest pain, shortness of breath, cough, pharyngitis, rhinorrhea, vomiting, diarrhea, epistaxis, melena, hematochezia, visual changes, or focal numbness. He noted that he recently returned from a multi-week trip to the Dominican Republic, where he had spent time in urban areas, at the beach, and in the mountains, as well as swimming in both saltwater and freshwater.  His social history was notable for occasional alcohol consumption but was otherwise unremarkable.

Vital signs were notable for a temperature of 101.5 degrees Fahrenheit and otherwise were within normal limits. On exam, he appeared fatigued but did not appear toxic. The remainder of a complete physical examination was otherwise unremarkable. CBC was notable for WBC 3.5, Hgb 16.5, platelet count 15. Complete metabolic panel was notable for a sodium of 131, creatinine 1.15, AST 66, ALT 47. Blood parasite smear, HIV testing, hepatitis panel, and respiratory pathogen panel were all negative. Chikungunya antibody and Dengue IgM antibody labs were sent. CXR revealed no acute cardiopulmonary process. EKG showed normal sinus rhythm. The patient received Tylenol and one liter of normal saline. He was admitted to the inpatient medicine service for further management.

DIAGNOSIS

Dengue virus infection was thought to be the most likely diagnosis in this case, given recent travel to endemic area, fever, myalgias/arthralgias, as well as laboratory findings of thrombocytopenia, leukopenia, elevated hemoglobin, and liver function test abnormalities. Additional potential diagnoses included chikungunya virus, Zika virus. However, thrombocytopenia is more common in dengue, and joint swelling is usually seen in patients with chikungunya virus. Patients with Zika typically have conjunctivitis. Other items on the differential, including HIV, hepatitis, adenovirus, and malaria were ruled out in the emergency department.

DISCUSSION

Dengue virus is transmitted via the bite of the Aedes aergypti mosquito, which is found in mostly tropical and subtropical regions. Dengue is endemic to more than one hundred countries, and has been seen in Central and South America, the Caribbean, Africa, southeast and south Asia, the western Pacific, Australia, some parts of Europe, some regions of the United States, and other locations. There are an estimated 390 million dengue infections yearly, and deaths from dengue increased to more than 40,500 annually from 2007-2017.

Dengue typically presents with non-specific symptoms including fever, rash, myalgias, arthralgias, headache, eye pain, nausea, vomiting, and petechiae. In 2009, dengue was divided into three classifications by the WHO: dengue without warning signs, dengue with warning signs, and severe dengue. See Figure 1 for a detailed description. As demonstrated in Figure 1, severity of infection varies widely between patients. Many infections many be asymptomatic. A variety of host, viral, and vector characteristics are hypothesized to impact risk of infection and disease severity. Severe dengue more often occurs during second or other subsequent dengue infections in a patient who has already had dengue once.

Figure 1. WHO Classifications of Dengue Virus Infection

The 2009 WHO guidelines also include recommendations for disposition of patients with dengue or presumed dengue. Regarding disposition, outpatient management is considered safe for patients without warning signs and without comorbid conditions. Inpatient management is recommended in patients with dengue without warning signs who also have coexisting conditions. Coexisting conditions highlighted in the guidelines include pregnancy, infancy, advanced age, diabetes, asthma, hypertension, renal failure, or those with personal or social factors that may limit their ability to seek follow up care or return to the hospital for worsening symptoms. Inpatient management is also recommended for any patient with warning signs or severe dengue.

Treatment for dengue is largely supportive. The risks of severe infection and shock are greatest on days 3-6 of illness. In non-severe dengue, symptoms usually improve within 7-10 days.  A variety of antivirals and steroid therapies have been investigated in the treatment of dengue, without substantial improvement in outcomes, length of hospitalization, or recovery time. Intravenous or oral fluid resuscitation based on clinical volume status, urine output, and vital signs is recommended. Acetaminophen should be used for fever and pain. Aspirin and NSAIDs should be avoided due to their effects on platelet function. Blood and/or platelet transfusions should be given in keeping with standard transfusion guidelines. 

CASE RESOLUTION

While admitted, the patient’s dengue IgM antibodies came back elevated. Additional testing included negative chikungunya virus antibodies and negative parvovirus antibodies. The patient was evaluated by infectious disease (ID), who recommended supportive care for dengue and close clinical monitoring. ID also recommended empiric treatment for leptospirosis with doxycycline, given clinical picture and patient report of swimming in stagnant water while on his trip. The patient remained hemodynamically stable and did not develop signs of hemorrhage, shock, or worsening liver or renal function. His cell lines improved within several days without intervention. He was discharged in good condition with primary care follow up.

TAKE-AWAYS

  • Dengue is a febrile viral illness transmitted by mosquitoes in endemic areas.

  • Clinical presentation can be nonspecific and varies from asymptomatic to severe, life-threatening illness.

  • Common laboratory findings include leukopenia, thrombocytopenia, increased hemoglobin, and elevated AST/ALT

  • Those with coexisting conditions, as well as those with warning signs or severe dengue should be admitted.

  • Treatment is largely supportive care.

Author: Alexandra Pusateri, MD, is a current second-year resident at Brown Emergency Medicine Residency.

Faculty Reviewer: Michelle Myles, MD, is an assistant professor and clinician educator at Brown Emergency Medicine.

REFERENCES

Paz-Bailey G, Adams LE, Deen J, Anderson KB, Katzelnick LC. Dengue. The Lancet. Published online January 1, 2024. doi:https://doi.org/10.1016/s0140-6736(23)02576-x

Comprehensive Guideline for Prevention and Control of Dengue and Dengue Haemorrhagic Fever. Revised and expanded edition. World Health Organization. Available at: https://apps.who.int/iris/handle /10665/204894. (Accessed on April 2, 2024).

Wilder-Smith A, Ooi EE, Horstick O, Wills B. Dengue. The Lancet. 2019;393(10169):350-363. doi:https://doi.org/10.1016/S0140-6736(18)32560-1

Gulati S, Maheshwari A. Atypical manifestations of dengue. Tropical Medicine & International Health. 2007;12(9):1087-1095. doi:https://doi.org/10.1111/j.1365-3156.2007.01891.x

World Health Organization. Dengue: Guidelines for diagnosis, treatment, prevention and control, New edition. WHO: Geneva 2009. http://www.who.int/tdr/publications/ documents/dengue-diagnosis.pdf?ua=1 (Accessed on April 2, 2024).

Srikiatkhachorn A, Rothman AL, Gibbons RV, et al. Dengue—How Best to Classify It. Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America. 2011;53(6):563-567. doi:https://doi.org/10.1093/cid/cir451

Global EM, Infectious Disease, Public HealthAlexandra PusateriInfectious Disease, Global EM, Emergency MedicineComment