Congenital Annular Erythema in Two Newborns: Similar Morphology, Divergent Etiologies

Abstract

The inconsistent use of the term “erythema annulare centrifugum” has created confusion, in that it has been applied to a group of distinct diseases as if they were a single condition. The literature becomes more ambiguous when different names are given to annular eruptions that have a similar pathogenesis. We present two neonates who presented at birth with similar diffuse erythematous annular eruptions, but differed in their serologic and histopathologic findings. The first child was otherwise healthy and had normal laboratories findings that excluded both infectious and autoimmune diseases. His biopsy showed a perivascular and interstitial infiltrate throughout the entire dermis that was composed of lymphocytes, histiocytes and numerous eosinophils. The second neonate had elevated anti‐Ro and anti‐La antibodies, thrombocytopenia and a non‐anion gap metabolic acidosis. His biopsy showed focal vacuolar degeneration of the basal layer. There was a perivascular and interstitial infiltrate that extended throughout the dermis which consisted primarily of nuclear debris. Within the cytoplasm of the few intact histiocytes and neutrophils, were hematoxylin bodies, giving these cells the appearance of LE cells. We discuss the clinical and histopathological findings in these two neonates and attempt to clarify the nomenclature pertaining to the annular erythemas.