Chronic recurrent multifocal osteomyelitis (CRMO)

What is chronic recurrent multifocal osteomyelitis (CRMO)?

CRMO—also called chronic nonbacterial osteomyelitis (CNO)—is a rare disorder that causes inflammation of the bone. CRMO is an autoimmune disease, in which the immune system mistakenly attacks healthy tissue and organs, causing inflammation.

Children with CRMO generally experience periods of pain and swelling of the affected bones, followed by periods of remission (no symptoms). It most commonly affects the long bones and can also affect the pelvis or the spine. It is sometimes diagnosed along with inflammatory bowel disease or psoriasis.

CRMO usually occurs in children around the age of nine or 10 and occurs more frequently in girls than in boys. It can affect one bone or multiple bones and can cause bone deformities or slow growth in children. With treatment, CRMO can go into remission; however, the possibility of recurrence usually requires life-long monitoring by a rheumatologist.

 What are the symptoms of CRMO?

The most common symptom of CRMO is pain in the bones. There may also be swelling in the joints, and for some children the pain is accompanied by a fever.

How is CRMO diagnosed?

To diagnose CRMO, a pediatric rheumatologist will first exclude the possibility of other diseases causing your child’s symptoms. Your physician will conduct a full medical exam and will most likely order some tests, which may include:

• X-ray looks for damage to the bone
• Magnetic resonance imaging (MRI) provides more detail than X-ray and can detect bone lesions.
• Blood tests can show elevated levels of inflammation
• Bone biopsy rules out infection or cancer, and shows inflammation

How is CRMO treated?

There is no cure for CRMO. The goal of treatment at Columbia’s Pediatric Rheumatology Program is to reduce pain, prevent bone growths and deformities, and help your child lead a normal, productive life. Depending on the severity of your child’s condition and the bones affected, your rheumatologist will prescribe medications, including:

• Non-steroidal anti-inflammatory medications (NSAID), such as naproxen, meloxicam, and indomethacin. Your rheumatologist will most likely prescribe these for pain.
• Antirheumatic drugs, such as corticosteroids or methotrexate. These immunosuppressive medications may be prescribed when pain and bone lesions continue despite treatment with NSAIDs.
• Biologics, such as etanercept, adalimumab, anakinra, and infliximab. These medications are given through injection or intravenously (through the vein).
• Bisphosphonates, such pamidronate and zoledronic acid. These medicines are administered intravenously.
• TNF inhibitors may be prescribed when CRMO is diagnosed along with inflammatory bowel disease (IBD) or psoriasis.

Follow up care for children with CRMO

We will schedule regular follow up appointments for your child with your pediatric rheumatologist. Follow up care may include repeat imaging tests (X-ray or MRI) to look for any recurrence.