european crystal network workshop



    J. Zaworski 1, E. Bouderlique 1, D. Anglicheau 2, JP. Duong Van Huyen 3, V. Gnemmi 4, JB. Gibier 4, Yann Neugebauer 5, JP. Haymann 1, D. Bazin 6, V. Frochot 1, M. Daudon 1, E. Letavernier 1

    1. Sorbonne Université, Inserm Umr S 1155, Aphp Service des Explorations Fonctionnelles Multidisciplinaires, Hôpital Tenon, 4 Rue de la Chine, 75020 Paris, France; 2. Paris Descartes, Sorbonne Paris Cité University, Inserm U1151, Department of Nephrology and Kidney Transplantation, Necker Hospital, Assistance Publique - Hôpitaux de Paris (Ap-Hp), Paris, France. 3. Paris Descartes, Sorbonne Paris Cité University, Department of Pathology, Necker Hospital, Assistance Publique - Hôpitaux de Paris (Ap-Hp), Paris, France. 4. Univ. Lille, Cnrs, Inserm, Chu Lille, Department Of Pathology, Umr9020 – Umr-S 1277 - Canther – Cancer Heterogeneity, Plasticity and resistance to therapies, F-59000 Lille. 5. Service de Néphrologie Et Dialyse, Centre Hospitalier de Douai, 59507 Douai, France; 6. Laboratoire de Chimie Physique, Université Paris Sud, Orsay, France


    We report herein three cases of acute crystalline nephropathy due to intratubular precipitation of 1-methyl uric acid (1-MUA), in the native kidneys of 2 drug-addict patients and in one kidney transplant recipient. All patients presented acute kidney injury with tubular defects (mild proteinuria, leucocyturia). Crystals were identified as obstructive greenish intratubular material. One-methyl uric acid crystallites were diagnosed by infrared spectroscopic imaging in three kidney biopsies and by infrared spectroscopic analysis of urine crystals in one. 1-MUA nephropathy may result from high caffeine intakes and probably from drugs interfering with caffeine metabolism. Indeed, 1-MUA is one of the 13 metabolite of caffeine which is excreted in the urine. 1-MUA nephropathy should be suspected in drug addicts affected by acute renal failure or when polarizing crystals are identified in a kidney biopsy. Infrared spectroscopic analysis is mandatory to properly diagnose this rare crystalline disease