Diagnostics

The diagnosis of fibromyalgia is based on symptoms alone. Imaging studies and biomarkers (e.g., ESR) are typically normal.

• Consider the diagnosis in patients with cardinal symptoms of fibromyalgia (± fibro fog) for ≥ 3 months.

• Order CBC and either ESR or CRP to identify a concomitant inflammatory condition. [7]

• Limit additional studies to specific conditions being considered, e.g: [7]

  • Rheumatoid factor, antinuclear antibodies, myositis-specific antibodies

  • Thyroid-stimulating hormone

  • Sleep studies

Eliciting pain at ≥ 11 of 18 tender points is a nonspecific finding and is no longer recommended in the assessment of fibromyalgia.

• Functional syndromes

  • Chronic fatigue syndrome

  • Irritable bowel syndrome

  • Migraine or tension headaches

  • Chronic pelvic pain syndrome, bladder syndromes

• Psychiatric disorders

  • Depressive disorders

  • Generalized anxiety disorder

• Inflammatory conditions

  • Systemic lupus erythematosus

  • Rheumatoid arthritis

Other

• Polymyalgia rheumatica

• Hypothyroid myopathy

• Complex regional pain syndrome

• Sleep apnea

• Lyme disease

• Malignancy

• See also “Differential diagnoses of myopathies.”

Myofascial pain syndrome

• Definition: a chronic pain syndrome caused by muscle tension, injury, or repetitive motion and characterized by the presence of trigger points in muscles and/or fascia (small tender knots) [10]

• Clinical features

  • Pain is mostly confined to one anatomical region: fewer tender points compared to fibromyalgia (≤ 11 of 18)

  • Leads to weakness and limited range of motion

  • Jump sign (myofascial pain syndrome): A physical examination finding characterized by an involuntary, sudden jerk or wince in response to stimulation of a tender area or trigger point (not seen in fibromyalgia).

  • Fatigue, headache, and sleep disturbances are less frequent compared to fibromyalgia

• Treatment: physical therapy, massage, stretching, ice packs, NSAIDs