PAPER TYPE www.landesbioscience.com Dermato-Endocrinology e1-1 Dermato-Endocrinology, e1; January 2014; © 2014 Landes Bioscience REPORT Introduction Necrobiosis lipoidica (NL) is a rare chronic granulomatous dermatitis first described in 1929 by Oppenheim that usually appears in the lower extremities that affects about 0.3–1.2% of diabetic patients, the majority of whom have type 1 diabetes. 1 The etiology and pathogenesis of this disorder are still unclear. NL is characterized by a skin rash that usually affects the shins. The average onset is 30 y, with females being affected more com- monly. There are very few reported cases of necrobiosis lipoidica in children. We report a case of a 16 y old girl who developed lesions on the lower extremities and in the interscapular area, which is an unusual location. Case report The patient, a Caucasian 16-y-old girl, was born at term by non-consanguineous, healthy parents. Type 1 diabetes (T1DM) had been diagnosed at one year of age. Our patient’s medical history was otherwise unremarkable. Until the age of 12 she maintained an adequate glucose control with HbA1c < 34 mmol/ mol. Thereafter her glucose control progressively worsened with a HbA1c of 86 mmol/mol. At the age of 16, during a routine diabetes follow-up visit, the patient presented with erythematous subcutaneous nodular lesions which had appeared 4 mo earlier, initially in the pretibial area and subsequently in the interscapu- lar area. Her HbA1c was 64 mmol/mol and daily insulin require- ments were 0.95 U/kg/day. In the suspect of necrobiosis lipoidica, a skin biopsy was performed (lower extremities and interscapular area) (Figs. 1 and 2). The microscopic evaluation of the pretibial lesions was suggestive of necrobiosis lipoidica. The smaller lesions in the interscapular area showed signs of perivascular dermati- tis which could be consistent with early stages of necrobiosis lipoidica (Fig. 3). Local treatment with tacrolimus determined a progressive improvement of the lesions. Diabetes self-manage- ment education was reinforced and her HbA1c showed a gradual reduction. *Corresponding author: Giulio Frontino; Email: frontino.giulio@hsr.it Submitted: 11/25/2013; Accepted: 01/09/2014 http://dx.doi.org/10.4161/derm.27790 Necrobiosis Lipoidica Diabeticorum A pediatric case report Clara Bonura 1 , Giulio Frontino 1, *, Andrea Rigamonti 1 , Roseila Battaglino 1 , Valeria Favalli 1 , Giusy Ferro 1 , Chiara Rubino 1 ,Paolo Del Barba 1 , Filippo Pesapane 2 , Gianluca Nazzaro 2 , Raffaele Gianotti 2 , Riccardo Bonfanti 1 , Franco Meschi 1 , and Giuseppe Chiumello 1 1 Ospedale San Raffaele Scientific Institute; Department of Pediatrics; Milano, Italy; 2 Università degli Studi di Milano; Fondazione IRCCS Ca’ Granda Osp. Maggiore Policlinico; Department of Pathophysiology and Transplantation; Milano, Italy Keywords: diabetes, necrobiosis lipoidica, T1DM, skin lesion, type 1 diabetes, granulomatous dermatitis, children Abbreviations: NL, Necrobiosis lipoidica, T1DM, Type 1 diabetes Introduction: Necrobiosis lipoidica (NL) is a rare chronic granulomatous dermatitis that usually appears in the lower extremities. It affects about 0.3–1.2% of diabetic patients, the majority of whom have type 1 diabetes. The etiology and pathogenesis of this disorder are still unclear. NL is characterized by skin rash that usually affects the shins. The average onset is 30 years, with females being affected more commonly. There are very few reported cases of necrobiosis lipoidica in children. Case report: We report a case of a 16 year old girl affected by type 1 diabetes mellitus (15 years disease duration) who developed an erythematous nodular rash on the lower extremities and interscapular area. In the suspect of necrobiosis lipoidica, a skin biopsy was performed (lower extremities and interscapular area). The microscopic evaluation of the pre- tibial lesions was suggestive of necrobiosis lipoidica. The smaller lesions in the interscapular area showed signs of peri- vascular dermatitis which could be consistent with early stages of necrobiosis lipoidica. Local treatment with tacrolimus determined a progressive improvement of the lesions. Conclusion: In patients with T1DM, diagnosis of NL of the lower legs is usually unequivocal. However, diagnosis may be more challenging in the presence of lesions with recent onset and/or atypical clinical presentation and unusual site. In these cases, NL must always be taken in consideration in order to avoid misdiagnosis, wrong/late treatment decisions and progression to ulceration.