As many patients with rare diseases know, it can sometimes be difficult to achieve the correct diagnosis. In fact, the average length of time it takes from symptom onset to diagnosis is around 4.8-5 years. In the case of chronic recurrent multifocal osteomyelitis (CRMO), or chronic nonbacterial osteomyelitis (CNO), the condition is often mistaken for other illnesses, such as bone infections or bone cancer. As a result, researchers have seen patients go for up to 15 years between symptoms and diagnoses. As reported by the Hospital for Special Surgery (HSS), researchers aimed to combat this problem by finding new diagnostic factors or criteria for CRMO. You can find the full study in the American College of Rheumatology (ACR) Meeting Abstracts.
Sourcing data from the REDCap database, researchers analyzed 409 patient files. Patients lived across 4 separate continents. Of the 409 files, 145 (35.5%) were conditions that mimicked CRMO. 264 files (65.5%) were CRMO. Researchers discovered that:
- Patients with CRMO were more often female. They had intermittent (irregular) pain as opposed to continuous pain. Additionally, they were less likely to have a fever than others, mimicking conditions.
- Bone lesions with this condition were more commonly symmetric.
- CRMO caused more swelling near the clavicle (collarbone).
- This condition more commonly affected the feet, collarbone, sternum, pelvis, bilateral femur and tibia, and unilateral fibula. However, when looking at imaging, researchers saw less abscesses and disorganized bone formations.
By understanding how this condition presents, researchers are more likely to achieve accurate diagnoses.
Chronic Recurrent Multifocal Osteomyelitis (CRMO)
Also known as chronic nonbacterial osteomyelitis, CRMO is an inflammatory bone disorder that generally begins during childhood. While there is no definitive answer as to what causes CRMO, it has been linked to an autoimmune response (the immune system mistakenly attacking bones) and gene mutations. In many cases, it resolves on its own and leaves patients without any lasting impact. However, in other cases, it causes bone deformities and prevents healthy growth. This disorder may occur alone or alongside other conditions like inflammatory bowel disease (IBD). Generally, females are affected more than males. Symptoms include:
- Bone and muscle tenderness
- Bone lesions
- Joint pain and swelling
Learn more about CRMO.