INTRODUCTION: Congenital rubella, which should disappear with widespread vaccination and mandatory obstetrical care, can occur as a purpuric eruption in the newborn. We report a case of blueberry muffin baby.CASE REPORT: An infant delivered after an "uneventful" pregnancy presented a generalized "purpuric" eruption and had axial hypotonia. Histology of a biopsy showed evidence of cutaneous erythropoiesis. The complete workup led to the diagnosis of congenital rubella.DISCUSSION: Cutaneous erythropoiesis is a well defined clinical and histological entity. There are several causes including infection and hematology disorders. Metastasis of a neuroblastoma, which must be eliminated by early biopsy, is the main differential diagnosis.CONCLUSION: Blueberry muffin rash is never idiopathic. The prognosis depends on the cause. Physicians should remember that congenital rubella has not yet been completely eradicated in France.
Diagnosis, Differential Hematopoiesis