When parents notice their child struggling with mysterious and recurring pain, it can be both confusing and worrying. Chronic Recurrent Multifocal Osteomyelitis (CRMO) is one relatively rare but impactful condition that causes inflammation in the bones, leading to discomfort and other challenges.
New treatments continue to improve outcomes for those diagnosed with this chronic condition. CRMO also has a generally favorable prognosis, which can provide families with some reassurance.
What is CRMO?
Chronic recurrent multifocal osteomyelitis (CRMO) is characterized as an auto-inflammatory bone disorder, which means it results from the immune system causing inflammation without any infection present. The current medical terminology puts CRMO under the umbrella term of CNO (or chronic nonbacterial osteomyelitis), and it serves as a diagnosis of exclusion that can mimic other conditions, like infection or malignancy.
CRMO primarily affects children and teenagers, with peak onset of the disease occurring between the ages of 7 and 12.
CRMO typically involves multiple sites of bone inflammation (osteomyelitis) that recur over time, hence the terms “multifocal” and “recurrent.” While it was previously thought to be very rare, it’s now considered to be somewhat more common. Still, its prevalence is only about four per one million children.
Common Symptoms of CRMO
The symptoms of CRMO can vary but generally include:
- Pain and tenderness in the affected bones that might worsen at night or during physical activity
- Joint pain, swelling and warmth over the areas of inflammation, with symptoms that feel similar to arthritis
- Periodic fevers and general malaise (feelings of being unwell and tired)
- Reduced mobility in nearby joints, depending on the bones affected
- Slowed growth due to bone deformities
- Increased risk of bone fractures
Many people with CRMO experience periods of remission when symptoms improve for a period of time. It’s common, however, for symptoms to return, especially when treatments are stopped.
CRMO Causes and Risk Factors
The exact cause of CRMO is poorly understood, but experts believe that the condition is related to the immune system malfunctioning and mistakenly attacking the body’s tissues.
Genetic factors are thought to play a role in its development, as the condition appears multiple times within families in a small percentage of cases.
CRMO is more commonly diagnosed in females than males and typically first appears in children and adolescents.
Diagnosing CRMO and Treatment Options
Patients with CRMO are generally treated by pediatric rheumatologists who specialize in inflammatory disorders of the joints and bones.
Diagnosis of CRMO is based on exams including x-rays, bone scans or MRI, as well as bone biopsy and blood tests. Because CRMO is rare, diagnosis can take longer than other conditions, with the average time to receive a diagnosis being 15 months.
There is currently no cure for CRMO. However, there are treatments that can help manage symptoms and prevent flare-ups.
Pediatric rheumatologists and other specialists monitor the patient’s response to treatment, adjust therapies as needed, and coordinate care with other healthcare providers. In order to reduce discomfort as much as possible and allow young people with this condition to maintain normal body function, a multidisciplinary approach is often necessary.
Treatments for CRMO often involve a combination of:
- Nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce inflammation and pain
- Corticosteroids or other immune-modulating medications to help control the immune system’s activity, including antirheumatic drugs (DMARDs)
- Physical therapy and occupational therapy to maintain or improve joint function and mobility
Regular follow-up appointments are usually important to monitor the effectiveness of the treatments and make adjustments as needed.
With appropriate management, many young people with CRMO can lead active, fulfilling lives, although they may experience certain physical limitations or periods of increased symptoms that require additional medical attention.
Patients and families can consult with the Stony Brook Children’s Pediatric Specialists in Rheumatology for more detailed information and support, which offers comprehensive care for children with CRMO and other rheumatological conditions. Pediatric Rheumatology, which covers rheumatic and autoimmune diseases, is such a rare specialty that there are only about 300 pediatric rheumatologists in the country. Stony Brook Children’s is the only hospital in Suffolk County and just one of two on Long Island to offer this specialty for children. Learn more about scheduling a consultation here.
