CTNNB1 and dengue disease: As the clinical presentation, imaging features and histopathology of DF and DF-like LGOS show much overlap, the objective of this study was to investigate the value of cytogenetic analysis, molecular pathology and immunohistochemistry in discrimination of these two mimickers.<h4>Case presentation</h4>A mutation in <i>CTNNB</i> (S45F) and nuclear beta-catenin immunostaining were observed in DF.