Julie Delyon1, Nicolas Ortonne2, Emmanuel Benayoun3, Julien Moroch2, Pierre Wolkenstein4, Emilie Sbidian5, Olivier Chosidow4. 1. Département de Dermatologie, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France. 2. Département de Pathologie, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France. 3. Département de Hématologie Biologique, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France. 4. Département de Dermatologie, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France; Inserm, Centre d'Investigation Clinique 1430, Créteil, France; Equipe d'Accueil (EA) EpiDermE, Université Paris-Est Créteil, Créteil, France. 5. Département de Dermatologie, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France; Pôle Recherche Clinique Santé Publique, Assistance Publique-Hôpitaux de Paris (AP-HP) Hôpitaux universitaires Henri Mondor, Créteil, France; Inserm, Centre d'Investigation Clinique 1430, Créteil, France; Equipe d'Accueil (EA) EpiDermE, Université Paris-Est Créteil, Créteil, France.
Abstract
BACKGROUND: Skin toxicity during low-dose methotrexate therapy is rare, ill described, and reported to have nonspecific histologic characteristics. Thus, misdiagnosis is common in patients with mucosal ulcers and/or skin erosions related to low-dose methotrexate. OBJECTIVE: We sought to describe the features of skin toxicity induced by low-dose methotrexate. METHODS: We evaluated the clinical and histologic features in 5 patients who experienced skin toxicity induced by low-dose methotrexate between 2011 and 2013. RESULTS: All 5 patients had acute mucosal ulcers, 4 had moderately abnormal blood cell counts, and 3 had skin erosions. In 3 patients, methotrexate dosage or dosing-schedule errors were identified. No other contributing factors (eg, renal dysfunction or interacting drugs) were identified. Mucocutaneous biopsy specimens consistently showed multiple dystrophic keratinocytes. LIMITATIONS: We studied only 5 patients and obtained no sensitivity or specificity data on the diagnostic value of keratinocyte dystrophy. CONCLUSION: Keratinocyte dystrophy may help to diagnose skin toxicity of low-dose methotrexate, even in the absence of known risk factors or methotrexate administration errors. Studies of the diagnostic performance of this histologic sign are needed.
BACKGROUND:Skin toxicity during low-dose methotrexate therapy is rare, ill described, and reported to have nonspecific histologic characteristics. Thus, misdiagnosis is common in patients with mucosal ulcers and/or skin erosions related to low-dose methotrexate. OBJECTIVE: We sought to describe the features of skin toxicity induced by low-dose methotrexate. METHODS: We evaluated the clinical and histologic features in 5 patients who experienced skin toxicity induced by low-dose methotrexate between 2011 and 2013. RESULTS: All 5 patients had acute mucosal ulcers, 4 had moderately abnormal blood cell counts, and 3 had skin erosions. In 3 patients, methotrexate dosage or dosing-schedule errors were identified. No other contributing factors (eg, renal dysfunction or interacting drugs) were identified. Mucocutaneous biopsy specimens consistently showed multiple dystrophic keratinocytes. LIMITATIONS: We studied only 5 patients and obtained no sensitivity or specificity data on the diagnostic value of keratinocyte dystrophy. CONCLUSION: Keratinocyte dystrophy may help to diagnose skin toxicity of low-dose methotrexate, even in the absence of known risk factors or methotrexate administration errors. Studies of the diagnostic performance of this histologic sign are needed.