False-positive dengue IgM test result in a patient with systemic lupus erythematosus: a case report

Abstract

Dengue virus infection most commonly has mild-to-moderate nonspecific clinical presentations that overlap with other diseases. Dengue-specific tests are commonly used for those patients with acute febrile illness in dengue-endemic areas. There is one study in vitro that showed a false-positive dengue-immunoglobulin M (dengue IgM) test for blood from a patient with systemic lupus erythematosus (SLE). Here, we demonstrated a false-positive dengue IgM test in a patient with SLE. The patient had fever, cytopenia, and a skin rash, but her clinical variables more closely matched with the criteria for SLE than the dengue infection. Vasculitis-like-lesions supported prednisolone administration and her clinical symptoms improved. This case highlights that some patients with SLE can be misdiagnosed as having a viral infection. These two diseases have similar clinical findings, such as acute febrile illness, but they are different in terms of their treatments and disease prognosis.

Case report: liver failure as a debut of autoimmune hepatitis triggered by dengue virus in a pregnant woman

“…Sin embargo, la información sobre el virus del dengue como posible desencadenante del sistema inmunológico es limitada, con solo un reporte de caso que asocia infección por dengue y HAI (7) . La serología de la infección por IgM del dengue puede mostrar falsos positivos en ciertos pacientes, como se ha reportado en lupus eritematoso sistémico y en estudios in vitro (15,16) . Una hipótesis es que este fenómeno puede deberse a la reactividad cruzada entre la proteína no estructural (NS) que es específica del virus del dengue y su interacción con las células del huésped, o podría deberse a la presencia de anticuerpos del factor reumatoideo, que puede desencadenar una unión no específica en el recubrimiento en los anticuerpos anti-humanos IgM (16,17) .…”

False-Positive Nonstructural Protein 1 Antigen in a Patient with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: A Case Report with Literature Review

“…Cells in patients with hematologic malignancies rapidly proliferate and can produce a small-molecular-weight protein [ 13 ], and this protein may bind in a way similar to that in the dengue NS1 antigen test [ 9 ]. Hematologic malignancies can produce a large number of nonspecific proteins which can coat the NS1 antigen [ 3 , 14 ]. It is hypothesized that this is similar to false-positive results with the dengue test kit in patients with positive rheumatoid factor.…”

“…Apart from the nonspecific symptoms, laboratory parameters (eg, leucopenia, increased atypical lymphocyte cells, and thrombocytopenia) can be used to assess the viral etiology [ 1 ]. The combination of clinical presentations and laboratory parameters may help physicians to distinguish between dengue infection and other conditions (eg, human immunodeficiency virus, septicemia, an autoimmune disorder, and hematological malignancies) [ 2 , 3 ]. The nonstructural protein 1 (NS1) antigen is a reliable diagnostic test kit for dengue infection, which showed sensitivity and specificity of 48.5–58.6% and 92.5–99.4%, respectively, and the positive predictive value was 88.5–99.3% [ 4 – 6 ].…”