Chronic Recurrent Multifocal Osteomyelitis and Its Management

Chronic recurrent multifocal osteomyelitis (CRMO) is an inflammatory disorder of bones first reported by Giedion et al. in 1972. It is a disease of childhood, comparable to SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) in adults. CRMO presents with pain and swelling overlying the involved bones. Inflammatory markers are usually raised and X-rays usually show sclerotic lesions. MRI demonstrates the extent of the lesions accurately and associated soft tissue changes. Nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids are the mainstays of the management. We report three patients who presented with bone pains. Extensive workup and radiological modalities along with clinical findings supported the diagnosis of CRMO. This article highlights important clinical presentations, radiological findings, and various management options.

A pediatric case of SAPHO-CNO syndrome with clinical correlation between cutaneous and osteoarticular features

Synovitis acne pustulosis hyperostosis osteitis (SAPHO) and chronic nonbacterial osteomyelitis (CNO) represent overlapping osteoarticular autoinflammatory syndromes, with a minority displaying neutrophilic skin features at the time of diagnosis. The pathophysiological link and chronological timeframe between skin and osteoarticular findings remain ambiguous, which in turn can manifest in diagnostic delay. We present a rare pediatric case of SAPHO-CNO with a clear association between cutaneous and osteoarticular symptoms, treated with nonsteroidal anti-inflammatory medications, corticosteroids, and intravenous pamidronate. By raising physician awareness of these syndromes, we hope that appropriate management will be initiated in a more timely fashion avoiding unnecessary investigations and treatment.

Unusual onset of a case of chronic recurrent multifocal osteomyelitis

BACKGROUND

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare condition that commonly affects the clavicle and pelvis.

CASE PRESENTATION

We report here a case a 12 years old girl with CRMO arising with recurrent episodes of left supraorbital headache, followed by the appearance of a periorbital dyschromia. Magnetic resonance imaging (MRI) of the skull and orbits revealed an important subacute inflammatory process. Few months after, the child presented a painful swelling of the left clavicle; the histological examination of the related biopsy allowed to establish the diagnosis of CRMO.

CONCLUSION

CRMO presenting as acute headache involving neurocranium is rare; to our knowledge this is the first recognized case in the world literature. This pathological condition is frequently misdiagnosed as infection or neoplasm and needs a deep investigation for the differential diagnosis. The physical, laboratoristic and instrumental diagnostic investigations of the patient and the treatment employed are described in detail.

SAPHO syndrome: a review

INTRODUCTION

Synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) is an acronym for various osteoarticular and dermatological manifestations that can appear in the same patient. It is a rare syndrome, but since its awareness has increased, there have been more and more such reports in the literature.

AIMS

The objectives of this review are to summarize the current state of knowledge on pediatric and adult-onset SAPHO syndrome, and to discuss treatment strategies that should be considered.

RESULTS

The SAPHO syndrome can affect patients of any age, and its etiology is still not known. The syndrome has its cognizable radiological characteristics that are most important in making the diagnosis. There are several diagnostic criteria as well, but they need further validation. No standard treatment protocols are available and current treatment options are not evidenced-based due to the rarity of the syndrome. Therapy is empirical and aimed at easing pain and modifying the inflammatory process. It includes nonsteroidal anti-inflammatory drugs (NSAIDs) as the first-line agents. Antibiotics, corticosteroids, disease-modifying anti-rheumatic drugs, biologicals targeting tumor necrosis factor alpha or interleukin-1, and bisphosphonates have all been used with variable success. Surgery is reserved to treat complications. Even though it is a disease with good long-term prognosis, its treatment remains a challenge and the results are known to be disappointing, especially with the skin component of the disease.

CONCLUSION

It is expected that these patients present at the time of diagnosis and the treatment should be as early, effective, and safe as possible in order to prevent osteoarticular progression and to limit the adverse events associated with pharmacological drugs.

Autoinflammatory bone disorders with special focus on chronic recurrent multifocal osteomyelitis (CRMO)

Sterile bone inflammation is the hallmark of autoinflammatory bone disorders, including chronic nonbacterial osteomyelitis (CNO) with its most severe form chronic recurrent multifocal osteomyelitis (CRMO). Autoinflammatory osteopathies are the result of a dysregulated innate immune system, resulting in immune cell infiltration of the bone and subsequent osteoclast differentiation and activation. Interestingly, autoinflammatory bone disorders are associated with inflammation of the skin and/or the intestine. In several monogenic autoinflammatory bone disorders mutations in disease-causing genes have been reported. However, regardless of recent developments, the molecular pathogenesis of CNO/CRMO remains unclear.Here, we discuss the clinical presentation and molecular pathophysiology of human autoinflammatory osteopathies and animal models with special focus on CNO/CRMO. Treatment options in monogenic autoinflammatory bone disorders and CRMO will be illustrated.

A missense mutation in pstpip2 is associated with the murine autoinflammatory disorder chronic multifocal osteomyelitis

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory disorder that primarily affects bone but is often accompanied by inflammation of the skin and/or gastrointestinal tract. The etiology is unknown but evidence suggests a genetic component to disease susceptibility. Although most cases of CRMO are sporadic, there is an autosomal recessive syndromic form of the disease, called Majeed syndrome, which is due to homozygous mutations in LPIN2. In addition, there is a phenotypically similar mouse, called cmo (chronic multifocal osteomyelitis) in which the disease is inherited as an autosomal recessive disorder. The cmo locus has been mapped to murine chromosome 18. In this report, we describe phenotypic abnormalities in the cmo mouse that include bone, cartilage and skin inflammation. Utilizing a backcross breeding strategy, we refined the cmo locus to a 1.3 Mb region on murine chromosome 18. Within the refined region was the gene pstpip2, which shares significant sequence homology to the PSTPIP1. Mutations in PSTPIP1 have been shown to cause the autoinflammatory disorder PAPA syndrome (pyogenic arthritis, pyoderma gangrenosum and acne). Mutation analysis, utilizing direct sequencing, revealed a single base pair change c.293T --> C in the pstpip2 gene resulting in a highly conserved leucine at amino acid 98 being replaced by a proline (L98P). No other mutations were found in the coding sequence of the remaining genes in the refined interval, although a 50 kb gap remains unexplored. These data suggest that mutations in pstpip2 may be the genetic explanation for the autoinflammatory phenotype seen in the cmo mouse.