This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Type 2 lepra reaction is an example of which type of hypersensitivity reaction? \nSelect and explain. \nA. Type 1 hypersensitivity reaction, B. Type 2 hypersensitivity reaction, C. Type 3 hypersensitivity reaction, D. Type 4 hypersensitivity reaction', 'role': 'user'}, {'content': "Answer: C \nExplanation: Please Remember\nType of Lepra Reaction + Type of Hypersensitivity Reaction = 5\nType 1 Lepra Reaction is Type IV Hypersensitivity Reaction ic Cell Mediated Immunity (1 +4 = 5)\nType II Lepra Reaction is Type III Hypersensitivity Reaction ie Immune Complexes (2 + 3 = 5)\nType I Lepra Reactions (Downgrading and Reversal Reactions)\n\nPatients with borderline forms of leprosy hut not in patients with pure lepromatous disease.\nIt is Gell and Coombs type IV hypersensitivity reaction\nManifestations include classic signs of inflammation within previously involved macules, papules, and\xa0plaques and. on occasion, the appearance of new skin lesions, neuritis, and (less commonly j fever-—generally low-grade.\nThe nerve trunk most commonly involved in this process is the ulnar nerve at the elbow, which may be\xa0painful and exquisitely tender.\nThe most dramatic manifestation is foot dr op, which occurs when the peroneal nerve is involved.\nWhen type 1 lepra reactions precede the initiation of appropriate antimicrobial therapy, they are termed\xa0downgrading reactions. and the case becomes histologically more lepromatous: when they occur after the\xa0initiation of therapy, they are termed reversal reactions, and the case becomes more tuberculoid.\nReversal reactions often occur in the first months or years after the initiation of therapy but may also\xa0develop several years thereafter.\nEdema is the most characteristic microscopic feature of type 1 lepra lesions, whose diagnosis is primarily\xa0clinical.\n\nType 2 lepra reaction (Erythema nodosum leprosum )\n\nIt is an immune complex mediated hypersensitivity reaction\nIt is Gell and Coombs type III hypersensitivity reaction\nIn patients with polar lepromatous or borderline lepromatous leprosy and follows initiation of leprosy\xa0treatment\nCrops of erythematous, palpable, tender, papular, nodular or plaque lesions distributed bilaterally\xa0symmetrically, on face and extensor aspect of extremities.\nSkin biopsy - vasculitis or pannieulitis. lymphocytes with polymorphonuclear infiltrates\nElevated levels of circulating TNF-α\nFever and systemic manifestations like polyarthritis, lymphadenopathy, immune complex\xa0glomerulonephritis, epididymoorchitis and iridocyclitis.\nRisk factors are Multidrug therapy for leprosy, intercurrent infections, pregnancy, trauma, surgery,physical and mental stress\nCorticosteroids (prednisolone-0.5 to 1 mg/kg/ day] are the first line drugs\nClofazimine  and thalidomide  are second line drugs\nThalidomide is contraindicated in pregnancy as it is teratogenic.\n\nLucio's Phenomenon\n\nIt is an unusual reaction seen exclusively in patients from the Caribbean and Mexico.\nPatients with untreated diffuse lepromatosis form of lepromatous leprosy.\nRecurrent crops of large, sharply marginated. ulcerative lesions on the lower extremities.\nSecondary infection and septic bacteremia can be fatal.\nHistologically, the lesions are characterized by ischemic necrosis of the epidermis and superficial dermis,heavy parasitism of endothelial cells with AFB. and endothelial proliferation and thrombus formation in\xa0the larger vessels of the deeper dermis.", 'role': 'assistant'}]