History
Most patients develop the eruption a few weeks after starting therapy with the offending agent. In penicillamine use, the eruption may not develop until 6 months after the onset of therapy. Some patients may give a history of a nonspecific eruption prior to the development of pemphigus type lesions.
Physical Examination
Clinical manifestations of drug-induced pemphigus depend on the pathomechanism involved.
Disease caused by thiol drugs tends to present with the clinical findings of pemphigus foliaceus. Erythematous, scaly, crusted plaques occur primarily on the trunk. Occasional superficial vesicles and bullae may be seen, but usually, they are ruptured. Oral lesions do not occur.
Nonthiol drug-induced pemphigus presents predominantly as pemphigus vulgaris. Flaccid bullae and erosions occur on normal-appearing skin and, also, on the oral mucosa. [17]
Causes
Speculation exists that genetic predisposition may be important in non-thiol–triggered pemphigus. Human leukocyte antigen DR4 (HLA-DR4) is associated with idiopathic pemphigus; however, few studies have provided data concerning HLA typing in cases of drug-induced pemphigus.
Thiols implicated in drug-induced pemphigus are as follows:
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Penicillamine [10]
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Bucillamine [11]
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Captopril
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Lisinopril [12]
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Pyritinol
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Thiopronine
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Piroxicam
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Thiamazole
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5-Thiopyridoxine
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Gold sodium thiomalat
Antibiotics implicated in drug-induced pemphigus are as follows:
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Penicillin and derivatives
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Cephalosporins
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Quinolones [13]
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Rifampicin
Pyrazolone derivatives implicated in drug-induced pemphigus are as follows:
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Phenylbutazone
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Aminopyrine
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Azapropazone
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Oxyphenylbutazone
Miscellaneous drugs implicated in drug-induced pemphigus are as follows:
Complications
Secondary infections may occur in drug-induced pemphigus because of the disruption of the skin barrier. Extensive erosions may promote entrance of bacteria, resulting in cutaneous infections, bacteremia, or sepsis.
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Early small blister filled with clear fluid arises on healthy skin.
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Flaccid blister filled with clear fluid arises on healthy skin.
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An erosion.