Interesting ImagesDiffuse Hypermetabolic Bone Marrow Infiltration in Severe Primary Hyperoxaluria on FDG PETTonnelet, David MD*; Benali, Khadija MD*; Rasmussen, Camille MD†; Goulenok, Tiphaine MD†; Piekarski, Eve MD*Author Information From the *Nuclear Medicine Department, Bichat Claude Bernard Hospital, Assistance Publique Hôpitaux de Paris, Inserm UMR-S 1148, Paris Diderot University †Internal Medicine Department, Bichat Claude Bernard Hospital, Assistance Publique Hôpitaux de Paris, Paris, France. Received for publication October 23, 2019; revision accepted March 3, 2020. Conflicts of interest and sources of funding: none declared. Correspondence to: Eve Piekarski, MD, Nuclear Medicine Department, Bichat Claude Bernard Hospital, Assistance Publique Hôpitaux de Paris, 46 rue Henri Huchard, 75018 Paris, France. E-mail: email@example.com. Clinical Nuclear Medicine: June 2020 - Volume 45 - Issue 6 - p e296-e298 doi: 10.1097/RLU.0000000000003047 Buy Metrics Abstract A 24-year-old man, with type 1 primary hyperoxaluria (diagnosed at age 20 years after repeated renal lithiasis, due to a I244T mutation frequently encountered in Mediterranean countries) complicated by end-stage renal failure requiring dialysis, was admitted for pancytopenia, refractory to erythropoietin injections. On clinical examination, he presented a hepatosplenomegaly without palpable adenopathy. 18F-FDG PET/CT revealed intense and diffuse bone marrow uptake in the axial skeleton and preferential long bone metaphyseal uptake. Bone marrow aspiration showed Gaucher-like cells infiltration due to oxalate accumulation in macrophages, leading to the diagnosis of bone marrow involvement by primary hyperoxaluria. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.