title: Chronic recurrent multifocal osteomyelitis in association with pyoderma gangraenosum.
abstract: BACKGROUND
  Chronic recurrent multifocal osteomyelitis (CRMO) is a rare acquired inflammatory skeletal disorder of unknown origin. CRMO was first described by Gideon in 1972 and mainly affects children and young adults of female gender. The CRMO is part of the clinical picture of non-bacterial Osteomyelitis (NBO) and typically presents a relapsing recurring course with both remission and spontaneous exacerbation. CRMO is typically encountered in the limbs and the metaphysis of long bones in particular. Usually the clinical symptoms include painful swellings of the affected regions. This case report describes the rare case of a CRMO of the mandible in association with pyoderma gangraenosum.
  
  
  METHODS
  A 14-year old female caucasian patient, residing in the south of Germany, presented in the oncological outpatient clinic of our Department of Paediatrics and Adolescent Medicine in June 2014 complaining of increasing neck pain and progressive swelling at her left cheek ongoing for about 6 weeks. These symptoms had been occurring quarterly for 4 years, but had never been as pronounced. Blood biochemistry showed a moderately elevated CRP (35 mg/l) and a significantly increased blood sedimentation rate (BSR 48/120 mm). The panoramic radiograph, however, revealed a bone alteration in the left mandibular region. Further investigations confirmed the diagnosis of CRMO.
  
  
  CONCLUSIONS
  The present case underlines the fact that rare diseases might occasionally present with even more rare symptoms. These occasions can obviously be considered to present a considerable diagnostic challenge.
authors: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nürnberg, Glückstrasse 11, 91054, Erlangen, Germany. Matthias.Wurm@uk-erlangen.de.
authors: Matthias Christian
authors: MC
authors: Wurm
authors: Department of Paediatrics and Adolescent Medicine, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Ines
authors: I
authors: Brecht
authors: Department of Radiology, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Michael
authors: M
authors: Lell
authors: Department of Pathology, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Kathrin
authors: K
authors: Brunner
authors: Department of Maxillofacial Surgery, Royal Free Hospital, London, UK.
authors: Konstantinos Theodorou
authors: KT
authors: Mitsimponas
authors: Department of Paediatrics and Adolescent Medicine, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Martin
authors: M
authors: Chada
authors: Department of Dermatology, University of Erlangen-Nürnberg, Erlangen, Germany.
authors: Julia
authors: J
authors: Jahn
authors: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nürnberg, Glückstrasse 11, 91054, Erlangen, Germany.
authors: Friedrich-Wilhelm
authors: FW
authors: Neukam
authors: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nürnberg, Glückstrasse 11, 91054, Erlangen, Germany.
authors: Cornelius
authors: C
authors: von Wilmowsky
mesh_terms: D000293:Adolescent; D002648:Child; D002908:Chronic Disease; D005260:Female; D005858:Germany; D006801:Humans; D010019:Osteomyelitis / Q000150:complications*; D011711:Pyoderma / Q000150:complications*; D012008:Recurrence
keywords: CRMO; Chronic recurrent multifocal osteomyelitis; NBO; Non-bacterial osteomyelitis; Pyoderma gangraenosum