<prompt> Row of tombstones appearance is seen in:Irritant dermatitisPemphigusPemphigoidHerpes zoster  <response>: Histopathology of pemphigus vulgaris Earliest changes -intercellular edema disappearance of intercellular bridges in the lower most epidermis. Loss of coherence between epidermal cells acantholysis -- formation of clefts --bullae in the suprabasal zone. Basal cells remain attached to the dermis, producing a tombstone appearance. Acantholytic cells are present in the bulla cavity. Scanty perivascular inflammatory infiltrate composed of lymphocytes, histiocytes and occasional eosinophils, neutrophils, and plasma cells is present 