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Vacuolar interface dermatitis (VAC, also known as liquefaction degeneration, vacuolar alteration or hydropic degeneration) is a dermatitis with vacuolization at the dermoepidermal junction, with lymphocytic inflammation at the epidermis and dermis.
Mild inflammatory cell infiltrate along the dermoepidermal junction (black arrow in image)
Vacuolization within the basal keratinocytes (white arrow in image)
Often necrotic, predominantly basal, individual keratinocytes, manifesting as colloid or Civatte bodies
Acute graft-versus-host-disease
Vacuolar alteration of various severity, from focal or diffuse vacuolation of the basal keratinocytes (grade I), to separation at the dermoepidermal junction (grade III)
Bolognia, Jean L.; et al. (2007). Dermatology. St. Louis: Mosby. p. 11. ISBN1-4160-2999-0.
^ Unless else specified in boxes, reference is: Alsaad, K O (2005). "My approach to superficial inflammatory dermatoses". Journal of Clinical Pathology. 58 (12): 1233–1241. doi:10.1136/jcp.2005.027151. ISSN0021-9746.
Lisa K Pappas-Taffer. "Lichen Sclerosus". Medscape. Updated: May 17, 2018