Hypothyroidism and Fibromyalgia

It is Monday morning, and your nurse hands you charts for 4 new patients. Each patient is a woman with widespread body pain, stiffness, and fatigue. In each patient, the pain affects both sides of the body above and below the waist. Each of these patients has already been evaluated by another physician: the diagnosis in each case was stress and fibromyalgia. The women were all advised that the pain was "nothing to worry about" and that they should reduce stress and practice distraction techniques. They are in your office today seeking a second opinion.

Here are the stories each patient has told your nurse.

PATIENT NO. 1 Mrs Sterns, 55 years old, has had generalized pain for the past 6 months. Every spring, she plants a showcase flower garden. This year, she hasn't even emptied out last year's beds. "I feel totally fatigued. I have no energy and just want to curl up in bed. All of my muscles and joints just ache."

PATIENT NO. 2 Ms Thomas, a 48-year-old hospital administrator, used to exercise in the gym every morning, complete a 10-hour workday, and then jog in the evening. For the past 2 years, she has been sore and achy all over and it takes all of her energy just to put in 8 hours at work. "I feel like an old lady who only wants to sit in a rocking chair knitting. Whenever I tell someone I feel bad, they say, 'But you look great!'"

PATIENT NO. 3 Mrs Brownley is a 45-year-old piano teacher who has had pain for the past 6 months. "I feel so run down and achy. I have pain from my neck to my toes. I really dread having my students come in for lessons."

PATIENT NO. 4 Mrs Schmidt is a 67-year-old homemaker who has experienced generalized pain for the past 4 months. Her husband just retired and they had planned to travel extensively, but her pain is holding them back. "Everything seems to cause me pain. It hurts to start moving in the morning, and I can't even comb my hair without severe pain."

What are the likely causes of widespread body pain in these 4 patients?

(Go to the next page to find out.)

Patients with generalized pain complaints are often viewed as symptom magnifiers who do not really have pain but are depressed. A comparison between patients with chronic pain who had either focal pain or diffuse pain revealed that those with widespread pain had a 17% higher average pain severity score.¹ In addition, disability and anxiety were more prevalent in those with diffuse pain (Figure 1).

Each of the patients in these cases describes the significant impact of pain on daily activities. This suggests high pain severity and disability, which often require aggressive treatment.

Widespread pain is perhaps one of the most challenging chronic pain complaints to evaluate because the causes can include a wide variety of both general medical conditions and chronic pain syndromes (Table 1). Although the chief complaints and brief histories in these 4 patients are typical, none provides enough information to formulate an educated diagnosis. Even though each patient has the same primary complaint, differences in history and examination offer ready clues to diagnostic possibilities (Table 2). Extracting these important features depends on a targeted evaluation that focuses on high-yield questions and examination findings that help distinguish among the many possible causes of widespread body pain.

A HIGH-YIELD, TARGETED EVALUATION

The same examination principles apply to each patient regarding features in the history, physical examination findings, and the need to proceed with testing. Details of the targeted examination are outlined in Table 3. It is important to target examinations to specific clinical scenarios to help confirm or refute clinical diagnoses.

A pain drawing and fibromyalgia tender point recording sheet are provided in Figures 2 and 3. It is often easier for patients to draw their pain than to describe it. In addition, patients typically discuss only their most severe pain areas. A pain drawing can help identify all areas affected by pain.

The fibromyalgia tender point examination is performed by pressing on 18 possible tender points with 4 kg of pressure. Tender point areas are the occiput, trapezius, supraspinatus, gluteal area, lower lateral cervical region, second costochondral junction, lateral epicondyle, greater trochanter, and medial knee. The examiner presses on each spot with his or her thumb until the nail bed blanches, which is equivalent to about 4 kg of pressure. After each spot is pressed, the patient is asked to rate his or her pain severity on a scale from 0 (pressure only) to 10 (excruciating pain). All tender points rated 2 or higher are considered positive.² A total of 11 positive tender points is needed to make the diagnosis of fibromyalgia.

APPLYING THE TARGETED EXAMINATION TO EACH PATIENT

PATIENT NO. 1

Mrs Sterns, the 55-year-old avid gardener

History:

• Pain drawing (Figure A) shows diffuse pain, with numbness in both feet.

• No additional medical diagnoses.

• Review of systems was positive for dry skin, hair loss, constipation, and weight gain.

Also, the patient complains that she feels cold. All of these symptoms have developed over the past 6 months.

Targeted examination:

• Overweight and apathetic.

• Mild bradycardia.

• Range of motion in neck, back, and extremities mildly limited by pain.

• Eight positive tender points on fibromyalgia examination.

• Normal gait. Mild generalized weakness; no focal neurologic deficits.

Testing:

• Results of thyroid function tests abnormal; mild anemia.

DIAGNOSIS:

HYPOTHYROIDISM

Hypothyroidism is the second most common endocrinologic disorder (behind diabetes): about 3% of adults are affected.^3,4 Like fibromyalgia, hypothyroidism often includes a wide variety of somatic complaints. Unlike the patient with fibromyalgia, whose physical examination results are typically normal, the patient with hypothyroidism may display weight gain, dry skin, thinning hair, edema, weakness, and general sluggishness. Generalized aches and pains may also occur in patients with thyroid disease. For example, in a study of subacute thyroiditis, arthralgias or myalgias were present in 16% of patients at presentation.⁵ In another study of 100 patients with primary hypothyroidism, 19% reported joint and/or muscle pain with stiffness.⁶

Hypothyroidism may also result in peripheral neuropathy--evidenced here by reports of mild numbness in the patient's feet. In early peripheral neuropathy, results of the general neurologic examination are often normal, as in Mrs Sterns.

PATIENT NO. 2

Ms Thomas, the 48-year-old hospital administrator

History:

• Pain drawing shows diffuse pain (Figure B), with patchy, nondermatomal numbness and burning.
• Pain started after patient was rear-ended, with $1000 damage to her car and no obvious bodily injuries other than aches and pains.

• No additional medical diagnosis.

• Review of systems positive for fatigue, poor sleep, eating difficulty with periods of diarrhea and constipation, migraines, frequent episodes of numbness affecting different parts of her body on different days, painful menses, and irritability.

Targeted examination:

• Bright, intelligent, enthusiastic.

• Appropriate weight.

• Full range of motion in neck, back, and extremities.
• Sixteen positive tender points.

• Walks briskly; has excellent strength, normal sensation.

Testing:

• Normal blood work results, except for mildly elevated levels of aspartate aminotransferase (AST).

DIAGNOSIS:

FIBROMYALGIA

Fibromyalgia may occur after trauma or spontaneously. Its cause is unknown. The disease affects about 3% of women and 0.5% of men.⁷ Although fibromyalgia is often perceived as a disease of young women, its prevalence increases with age: 7% of women 60 years and older are affected.

Ms Thomas is a very typical fibromyalgia patient--bright, hardworking, and motivated. Like Ms Thomas, fibromyalgia patients often look vigorous and energetic, despite complaints of high fatigue. Fibro-myalgia patients often hear that they look great and have excellent musculoskeletal and neurologic responses: "You look too good and move too well to have so much pain!" Laboratory test results are also typically normal.

Ms Thomas's elevated AST level is probably a reflection of the alcohol she drank with last night's dinner. Remember, however, that fibromyalgia is not a diagnosis of exclusion. Diagnosis requires widespread pain and the presence of 11 positive tender points. Consider fibromyalgia in patients who present with widespread pain; numerous somatic complaints; no obvious medical conditions; and normal findings from medical, neurologic, and musculoskeletal examinations.

PATIENT NO. 3

Mrs Brownley, the 45-year-old piano teacher

History:

• Pain drawing shows pain over the joints in both shoulders, elbows, hands, and feet (Figure C). Her worst pain is in her hands, which limits her ability to play the piano.

• Pain began slowly over about 6 weeks without any injury. She first noticed stiffness in a couple of her fingers that seemed to worsen when she tried to move them. Since then, the pain and stiffness have seemed to come and go.

• Morning stiffness generally lasts for 2 to 3 hours, causing her to discontinue morning lessons.

• Treated for breast cancer with lumpectomy and radiation 4 years ago. Normal mammograms since.

• Review of systems negative, except for fatigue and occasional low-grade fevers.

Targeted examination:

• Normal vital signs and stable weight.
• Swelling and tenderness in the metacarpophalangeal joints in both hands.

• Restricted range of motion in the hands as well as the shoulders.

• Nine positive tender points.

• Normal neurologic examination findings.

Testing:

• Mild anemia, positive antinuclear antibody, and elevated C-reactive protein (CRP) level.
• Bone scan negative for metastatic disease.

• Roentgenograms demonstrate soft tissue swelling in both hands.

DIAGNOSIS:

EARLY RHEUMATOID ARTHRITIS

Rheumatoid arthritis (RA) affects approximately 0.5% to 1% of all adults.⁸ Morning stiffness and joint swelling are characteristic features of this disease. Most arthritic patients report stiffness after extended rest; in patients who have osteoarthritis (OA), this stiffness generally diminishes fairly rapidly after the joints have been moved. In contrast, morning stiffness is often pronounced and persists for longer than 1 hour in persons with RA.

RA is also distinguished from OA by the location of joint symptoms. RA usually manifests with symmetric involvement of small joints. In contrast, OA is marked by asymmetric involvement of large, weight-bearing joints. In early RA, x-ray films are often remarkable only for soft tissue swelling; however, bony erosions develop rapidly with active disease during the first 2 years of illness.

PATIENT NO. 4

Mrs Schmidt, the 67-year-old homemaker

History:

• Pain drawing shows symmetric pain in the shoulders, hips, and thighs (Figure D). The worst pain is in the shoulders.

• She's very stiff for about 1 hour in the morning; movement of the joints intensifies her pain.

• She's having trouble getting out of bed and has started asking her husband to comb her hair in the morning.

• No other medical conditions.

• Review of systems is remarkable for low-grade fevers, fatigue, loss of appetite, and weight loss.

Targeted examination:

• Temperature of 37.2C (99F).

• Restricted range of motion in the shoulders.

• Muscle tenderness to palpation.

• Seven positive tender points.

Testing:

• Elevated CRP level.

DIAGNOSIS:

POLYMYALGIA RHEUMATICA

Polymyalgia rheumatica (PMR) is characterized by bilateral proximal pain and stiffness in the shoulders and hips. PMR occurs in older patients, and peaks in incidence between 70 and 80 years of age.⁹ The most common complaint is difficulty in combing the hair. Other typical complaints include difficulty in getting out of bed or rising from a chair, especially after prolonged sitting.

Inflammatory markers are elevated in patients with PMR. Diagnostic criteria typically require an erythrocyte sedimentation rate (ESR) higher than 40 mm/h.⁹ CRP, however, is a more sensitive measure for both diagnosis and determination of disease activity.¹⁰ In a large survey of 177 patients with PMR, the ESR was 30 mm/h or less in 10 patients (6%). CRP test results were only false-negative in 2 patients (1%). In addition, only 1 of the patients with a normal ESR also had a normal CRP level.

WIDESPREAD BODY PAIN CAN BE CAUSED BY A VARIETY OF CONDITIONS

Do not be dissuaded from carefully evaluating diffuse body aches and pain because reported pain levels, associated disability, and anxiety seem excessively high. Diffuse pain may be the presenting complaint for a wide variety of medical conditions. In addition, patients with widespread chronic pain syndromes tend to have more disability and distress than do patients with focal pain.¹ These patients typically require a more in-depth evaluation and aggressive treatment.

Editor's note: Dr Marcus's book Headache and Chronic Pain Syndromes: The Case-Based Guide to Targeted Assessment and Treatment will be published later this year. Information about this book is available at http://www.humanapress.com and http://www.dawnmarcusmd.com.

References:

REFERENCES

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