MKSAP Quiz: 1-year history of widespread joint, muscle pain
A 37-year-old woman is evaluated for a 1-year history of widespread joint and muscle pain, fatigue, poor sleep, and difficulty focusing. Following a physical exam and lab tests, what is the most likely diagnosis?
A 37-year-old woman is evaluated for a 1-year history of widespread joint and muscle pain, fatigue, poor sleep, and difficulty focusing. She also has irritable bowel syndrome and migraine headaches. Current medications are sumatriptan and topiramate.
On physical examination, vital signs are normal. No rash is present on the face or extremities. Joint examination shows normal range of motion and no joint swelling. Most soft tissue is tender to light palpation. Muscle strength is normal.
Laboratory evaluation shows a normal complete blood count, serum thyroid-stimulating hormone level, and urinalysis as well as an erythrocyte sedimentation rate of 20 mm/h.
Which of the following is the most likely diagnosis?
A. Fibromyalgia
B. Generalized osteoarthritis
C. Polymyalgia rheumatica
D. Rheumatoid arthritis
E. Systemic lupus erythematosus
MKSAP Answer and Critique
The correct answer is A. Fibromyalgia. This content is available to MKSAP 19 subscribers as Question 81 in the Rheumatology section. More information about MKSAP is available online.
This patient presents with widespread pain, fatigue, poor sleep, and cognitive symptoms of 1 year's duration. These symptoms are the hallmarks of fibromyalgia, a poorly understood but common chronic pain syndrome affecting 2% to 3% of the population. Diagnosis is suggested by history and can be confirmed with validated criteria (e.g., the 2016 revisions to the American College of Rheumatology Preliminary Diagnostic Criteria). This illness is not autoimmune or inflammatory, and extensive laboratory testing is not advised unless another comorbid disease is suggested. Although some patients may have tender points, assessment of tender points on examination is unreliable (particularly in men) and no longer among the clinical criteria for diagnosis. Fibromyalgia tends to be associated with other medically unexplained syndromes, including irritable bowel syndrome, and is especially common in patients with migraine headaches.
Generalized osteoarthritis (Option B) affects multiple joint groups. On joint examination, crepitus, decreased range of motion, bony enlargement, and sometimes effusion may be present. Generalized osteoarthritis is an unlikely diagnosis because it would not cause the widespread pain seen in this patient and occurs in older patients. In addition, the examination demonstrates no evidence of osteoarthritis in any joint.
Polymyalgia rheumatica (PMR) (Option C) is a clinical diagnosis based on characteristic symptoms in a patient older than 50 years and is supported by an elevated erythrocyte sedimentation rate. PMR is associated with pain and stiffness of the shoulder girdle and hip girdle. This patient's age, diffuse pain, and normal erythrocyte sedimentation rate are not compatible with PMR.
Rheumatoid arthritis (Option D) is an inflammatory arthritis that primarily affects small joints. Patients with rheumatoid arthritis present with discomfort in discrete joints, not diffuse pain. In addition, rheumatoid arthritis does not cause axial pain or myalgia. The musculoskeletal examination in a patient who has a 1-year history of untreated rheumatoid arthritis should reveal multiple swollen joints.
Systemic lupus erythematosus (SLE) (Option E) is an autoimmune disease that can affect any system in the body, including the skin, blood cells, joints, lung, central nervous system, and kidneys. Although patients with SLE can have concurrent fibromyalgia, patients with fibromyalgia rarely have SLE. This patient also has none of the hallmarks of SLE, such as autoimmune cytopenia, inflammatory arthritis, rash, kidney disease, or systemic inflammation.
Key Points
- Fibromyalgia is characterized by widespread pain, fatigue, poor sleep, and cognitive symptoms; diagnosis is suggested by history and can be confirmed with a validated questionnaire.
- Assessment of tender points on examination is unreliable and no longer among the clinical criteria for diagnosis of fibromyalgia.