Successful treatment with cladribine of Erdheim-Chester disease with orbital and central nervous system involvement developing after treatment of Langerhans cell histiocytosis.

INTRODUCTION: Erdheim-Chester disease (ECD) is a rare, systemic form of non-Langerhans cell histiocytosis of the juvenile xanthogranuloma family with characteristic bilateral symmetrical long bone osteosclerosis, associated with xanthogranulomatous extra skeletal organ involvement. In ECD, central nervous system (CNS) and orbital lesions are frequent, and more than half of ECD pa tients carry the V600E mutation of the protooncogene BRAF. The synchronous or metachronous development of ECD and Langerhans cell histiocytosis (LCH) in the same patients is rare, and the possible connection between them is still obscure. Cladribine is a purine substrate analogue that is toxic to lymphocytes and monocytes with good hematoencephalic penetration. CASE REPORT: We presented a 23-year-old man successfully treated with cladribine due to BRAF V600E-mutation-negative ECD with bilateral orbital and CNS involvement ECD developed metachronously, 6 years after chemotherapy for multisystem LCH with complete disease remission and remaining central diabetes insipidus. During ECD treatment, the patient received 5 single-agent chemotherapy courses of cladribine (5 mg/m2 for 5 consecutive days every 4 weeks), with a reduction in dose to 4 mg/m2 in a fifth course, delayed due to severe neutropenia and thoracic dermatomal herpes zoster infection following the fourth course. Radiologic signs of systemic and CNS disease started to resolve 3 months after the end of chemotherapy, and CNS lesions completely resolved within 2 years after the treatment After 12-year follow-up, there was no recurrence or appearance of new systemic or CNS xanthogranulomatous lesions or second malignancies. CONCLUSION: In accordance with our findings and recommendations provided by other authors, cladribine can be considered an effective alternative treatment for ECD, especially with CNS involvement and BRAF V600E-mutation-negative status, when interferon-alpha as the first-line therapy fails.

[Accessory bones of the feet--radiological analysis of frequency].

BACKGROUND/AIM: Accessory bones are most commonly found on the feet and they represent an anatomic variant. They occur when there is a failure in the formation of a unique bone from separated centre of ossification. The aim of this study was to establish their frequency and medical significance. METHODS: Anteroposterior and lateral foot radiography was performed in 270 patients aged of 20-80 years with a history of trauma (180) and rheumatology disease (90). The presence and distribution of accessory bones was analysed in relation to the total number of patients and their gender. The results are expressed in numeric values and in terms of percentage. RESULTS: Accessory bones were identified in 62 (22.96%) patients: 29 (10.74%) of them were found in female patients and 33 (12.22%) in males. The most common accessory bones were as follows: os tibiale externum 50%, os pemroneum 29.03%, os trigonum 11.29%, os vaselianum 9.68%. CONCLUSION: Accessory bones found in 23% of patients with trauma and some of rheumatological diseases. Their significance is demonstrated in the differential diagnosis among degenerative diseases, avulsion fractures, muscle and tendon trauma and other types of injuries which can cause painful affection of the foot, as well as in forensic practice.