A 50-year-old male with an autoimmune hemolytic anemia was diagnosed with dengue fever in 2007. He tested positive for dengue IgM serology and his platelet counts had increased to 150 x 109/dl by the sixth day of infection. He had previously been on multiple antibiotics and had received an allogeneic blood transfusion. Molecular testing for dengue showed that the virus was not present in his blood, although he did have some underlying immunodeficiency.
A CBC (complete blood count) is a laboratory test for determining whether a patient is infected with dengue. The results of this test will be useful in establishing the diagnosis. In patients with underlying polycythemia, an CBC is a valuable diagnostic tool, but the results should not be relied on alone. Regardless of the results, the diagnosis should be confirmed by a physician experienced in infectious disease management.
The diagnosis of dengue is complex, especially when a patient has underlying polycythemia. It is important to differentiate between the two. One study in an immunosuppressive drug-resistant man showed that recombinant DNV envelope protein domain III (EPIII) suppressed megakaryopoiesis in a humanized mouse model. Therefore, DNV EPIII may be a potential therapeutic target for thrombopenia.
A 58-year-old man presented with a four-day fever, chills, and erythematous rash. Serum tests showed a positive NS1 antigen and IgM antibodies. Further studies suggested that the patient had higher eosinophil levels on day 10 of fever. He recovered after supportive therapy. The results indicate that this case of dengue should be carefully considered.
The patient with underlying polycythemia should be evaluated for possible dengue to avoid further complications. A negative test for dengue IgM and IgG antibodies could indicate that the patient has an underlying polycythemia, but the symptoms may be due to another cause. CBC is the most accessible and sensitive test for determining the presence of dengue.
A 58-year-old man with a four-day history of fever, chills, and erythematous rash was diagnosed with dengue fever. Blood tests revealed a positive NS1 antigen and IgM antibodies to dengue virus, which are detected by the presence of dengue-specific antibody. Moreover, his platelet count increased to 400 x 109, 800 x109, and 1081 x109. This patient was referred to the emergency department for assessment of post-dengue reactive thrombocytosis.
Hematologic findings showed that 60% of patients with dengue developed thrombocytopenia on day four, compared to only 8% of patients with non-dengue-infection. While the majority of these patients had an underlying polycythemia, a thrombocytopenia of the lungs and heart was present in 5.8% of patients. These symptoms were related to an underlying polycythemia.