Acute generalized exanthematous pustulosis due to tetrazepam.
Tetrazepam is a benzodiazepine that is widely used in Spain as a muscle relaxant, with occasional cutaneous side effects. We report a patient who developed a generalized pruriginous cutaneous reaction compatible with acute generalized exanthematous pustulosis (AGEP) due to tetrazepam. Patch tests with bromazepam, diazepam, and tetrazepam were negative at 48 and 72 hours; however, the tetrazepam patch showed a positive reaction at 10 days. Immunohistochemical studies revealed a mononuclear infiltrate composed of CD4+ and CD8+ T lymphocytes. Analysis of interleukin (IL) 8 expression by quantitative polymerase chain reaction revealed increased IL-8 mRNA levels in patch test-positive skin. Lymphoblast transformation test (LTT) was positive with tetrazepam but not with diazepam. Positive patch test and LTT suggested that tetrazepam-specific lymphocytes might be responsible for a T cell-mediated reaction. These results support previous data suggesting an important role for IL-8 and drug-specific T cells in the pathogenesis ofAGEP and imply that the reaction was specific to tetrazepam with no cross-reactivity to other benzodiazepines.
Thomas
E
E
Allergy Department, Hospital La Paz, Madrid, Spain.
Bellón
T
T
Barranco
P
P
Padial
A
A
Tapia
B
B
Morel
E
E
Alves-Ferreira
J
J
Martín-Esteban
M
M
D018771:Arthralgia / Q000188:drug therapy; D001569:Benzodiazepines / Q000009:adverse effects* / Q000627:therapeutic use; D003061:Codeine / Q000627:therapeutic use; D003139:Common Cold / Q000188:drug therapy / Q000276:immunology; D003875:Drug Eruptions; D004342:Drug Hypersensitivity / Q000276:immunology*; D004890:Erythema / Q000139:chemically induced* / Q000276:immunology; D005076:Exanthema / Q000139:chemically induced* / Q000276:immunology; D005260:Female; D006801:Humans; D008875:Middle Aged; D009125:Muscle Relaxants, Central / Q000009:adverse effects* / Q000627:therapeutic use; D012882:Skin Tests
D009125:Muscle Relaxants, Central; D001569:Benzodiazepines; C005245:tetrazepam; D003061:Codeine