Page 119 - TD-3-3

Tumor Discovery

CASE SERIES
Chronic recurrent multifocal osteomyelitis

masquerading as multifocal bone Langerhans
cell histiocytosis in children: A case series from a

tertiary cancer center

Yamini Krishnan * , Gazel Sainulabdin 1 , V. P. Krishnan 1 , and N. T. K. Thanseer 2
1
1 Department of Paediatric Haematology, Oncology and Bone Marrow Transplantation, MVR Cancer
Centre and Research Institute, Calicut, Kerala, India
2 Department of Nuclear Medicine, MVR Cancer Centre and Research Institute, Calicut, Kerala, India

Abstract

Chronic recurrent multifocal osteomyelitis (CRMO), also known as chronic non-
bacterial osteomyelitis (CNO), is an autoimmune inflammatory bone disorder mainly
affecting children and adolescents. The clinical presentation varies from mild, self-
limiting unifocal bone inflammation, which is more common, to multifocal recurrent
disease. CRMO can be misdiagnosed as multifocal bone Langerhans cell histiocytosis
(LCH), infections, lymphoma, or metabolic bone disease. Clinical features are highly
variable and not very specific. Most children experience vague aches and pains over
prolonged periods but remain generally well and do not exhibit growth failure. In
*Corresponding author: this article, we describe a case series of three children who presented with multifocal
Yamini Krishnan
(dryamini@mvrccri.co) bone disease and were initially referred for LCH; however, detailed investigations
confirmed the diagnosis of CRMO. The treatment options included non-steroidal
Citation: Krishnan Y,
Sainulabdin G, Krishnan VP, anti-inflammatory drugs, corticosteroids, and disease-modifying anti-rheumatic
Thanseer NTK. Chronic drugs. Other treatment options included anti-tumor necrosis factor agents and
recurrent multifocal osteomyelitis bisphosphonates, similar to those used for autoimmune bone diseases. CRMO should
masquerading as multifocal bone
Langerhans cell histiocytosis be considered a differential diagnosis in children presenting with chronic, vague, and
in children: A case series from recurrent bony symptoms with or without systemic symptoms.
a tertiary cancer center. Tumor
Discov. 2024;3(3):3102.
doi: 10.36922/td.3102 Keywords: Chronic recurrent multifocal osteomyelitis; Langerhans cell histiocytosis;
Received: March 6, 2024 Chronic non-bacterial osteomyelitis; Multifocal bone disease
Accepted: May 28, 2024
Published Online: June 19, 2024
1. Background
Copyright: © 2024 Author(s).
This is an Open-Access article Chronic recurrent multifocal osteomyelitis (CRMO), also known as chronic non-
distributed under the terms of the
Creative Commons Attribution bacterial osteomyelitis (CNO), is an autoimmune inflammatory bone disorder mainly
License, permitting distribution, affecting children and adolescents. As a rare occurrence, there are no established
1
and reproduction in any medium, criteria for diagnosis. Due to the lack of awareness of the condition among the medical
provided the original work is
properly cited. community, CRMO is likely under-recognized and underreported.
Publisher’s Note: AccScience Altered cytokine and chemokine expression in innate immune cells has been
Publishing remains neutral with described in the pathogenesis of this autoimmune condition. Recently, familial clustering
regard to jurisdictional claims in
published maps and institutional of CRMO cases has been observed, leading to the discovery of susceptibility genes for
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affiliations. sterile osteomyelitis. The main pathophysiology of CRMO involves altered cytokine
Volume 3 Issue 3 (2024) 1 doi: 10.36922/td.3102