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What is "Row of tombstones" appearance is seen in: and explain in detail?
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