<prompt> Fibrinoid necrosis may be observed in all of the following, exceptMalignant hypeensionPolyaeritis nodosaDiabetic glomerulonephritisAschoffs nodules  <response>: Ref Robbins 7e p214,594,1008,;9e p44 Fibrinoid necrosis is a special form of necrosis, visible by light microscopy, usually in immune reactions in which complexes of antigens and antibodies are deposited in the walls of aeries. The deposited immune complexes, together with fibrin that has leaked out of vessels, produce a bright pink and amorphous appearance on HE prepara- tions called fibrinoid fibrin-like by pathologists Fig. 1-13. The immunologically mediated diseases e.g., poly- aeritis nodosa in which this type of necrosis is seen are described in Chapter 4 