A 50-year-old white woman presents with aching and stiffness in the trunk, hip, and shoulders. There is widespread muscle pain after mild exertion. Symptoms are worse in the morning and improve during the day. They are also worsened by stress. The patient is always tired and exhausted. She has trouble sleeping at night. On examination, joints are normal. ESR is normal, and Lyme antibody and HIV test are negative. A diagnosis is best made by which of the following?
A. Trial of glucocorticoidThe signs and symptoms suggest fibromyalgia. Fibromyalgia is a very common disorder, particularly in middle-aged women, characterized by diffuse musculoskeletal pain, fatigue, and nonrestorative sleep. The American College of Rheumatology has established diagnostic criteria for the disease, which include a history of widespread pain in association with 11 of 18 specific tender point sites. In this patient with very characteristic signs and symptoms, the identification of 11 specific trigger points would be the best method of diagnosis. Polymyalgia rheumatica may sometimes be in the differential diagnosis. In this patient PMR would be unlikely given the normal ESR. Fibromyalgia is distinct from inflammatory muscle disease like polymyositis or dermatomyositis. Patients with inflammatory muscle disease usually present with proximal muscle weakness and elevated muscle enzymes, whereas patients with fibromyalgia usually complain of musculoskeletal pain and have normal muscle enzymes. Muscle pain is less prominent in inflammatory muscle disease. Fibromyalgia has been associated with other somatic syndromes, including irritable bladder, irritable bowel syndrome, headaches, and temporomandibular joint pain. Patients with fibromyalgia have an increased lifetime incidence of psychiatric disorders, particularly depression and panic disorder. However, there is convincing evidence that fibromyalgia is a disease of abnormal central nervous pain processing associated with amplification of nociceptive stimuli. This suggests that lower thresholds for noxious stimuli are caused by a CNS abnormality of as yet undetermined etiology. Psychiatric evaluation would, therefore, be useful only for other psychiatric symptoms, not for diagnosis of fibromyalgia itself. Steroids and NSAIDs have not been shown to be helpful in fibromyalgia, since there is no evidence of inflammation.