Arias-Stella Reaction
Marisa R. Nucci, MD
Key Facts
Terminology
Altered cellular and nuclear change of epithelium most commonly associated with pregnancy
Clinical Issues
May occur anywhere in female genital tract
Microscopic Pathology
Usually focal finding
Affected glands show spectrum of nuclear and cytoplasmic changes
Cells often protrude into lumen imparting hobnail appearance
Enlarged cells with abundant eosinophilic to vacuolated cytoplasm and variably enlarged nuclei
Intranuclear cytoplasmic inclusions common; mitotic activity typically absent
 Arias-Stella reaction is typically a focal finding. In this example from the cervix, only a few glands are affected. At low-power examination, micropapillary and hobnail growth are present. |
 Arias-Stella reaction is characterized by a spectrum of nuclear atypia, abundant eosinophilic to vacuolated cytoplasm, and intranuclear inclusions  . |
TERMINOLOGY
Abbreviations
Arias-Stella reaction (ASR)
Synonyms
Arias-Stella phenomenon
Arias-Stella change
Arias-Stella effect
Definitions
Cytoplasmic and nuclear changes of epithelium most commonly associated with pregnancy
ETIOLOGY/PATHOGENESIS
Hormonal
Secondary to increased gonadotropin stimulation
CLINICAL ISSUES
Epidemiology
Incidence
