Lillia, a 43-year-old Hispanic female, presents with a one-year history of a chronically fatiguing illness. She has been on temporary disability since the eighth month of her illness. Lillia is married and has two children, ages four and six. She was born in Argentina, immigrated to the U.S. at age eight and has traveled extensively in South America and the U.S.

History of Present Illness.
Lillia describes constant, persistent fatigue. She awakens “exhausted” and reports sleeping or resting 16 hours a day.

In addition, she complains of difficulty concentrating, severe enough to keep her from reading a book or even the newspaper. Forgetfulness is one of her primary concerns, and she feels it has impacted her parenting. Her supervisor at work also noted several serious errors in judgment.

The illness began with an acute viral syndrome, described as flu-like but with an extraordinary degree of myalgia, in addition to photophobia, low-grade fever and fatigue. She was in bed for five days. When she returned to work, she was profoundly fatigued, had difficulty concentrating and complained of arthralgia of the large joints and hands.

At this time she noted both fatigue and cognitive impairments. Other symptoms include episodes of dizziness, persistent generalized pain, sore throat and tender lymph nodes in the neck and axillae.

Question: What additional questions are important when considering a diagnosis of CFS?

A)        Is the fatigue alleviated by rest periods?

B)        Does exertion worsen the symptoms of fatigue and muscle pain?

C)        Has the patient had any previous unexplained bouts of prolonged fatiguing illness?

Answer: All of the above. In order to meet the case definition for CFS (see back page), the fatigue must be severe and not relieved by sleep or rest, and cannot be the result of excessive work or exercise. The fatigue substantially impairs a person’s ability to function normally.

During post-exertional periods, muscle groups not immediately involved in the exertion are often affected. In most instances, the symptoms of CFS can be distinguished from the closely related phenomena of somnolence, muscle weakness, neuromuscular fatigability, depressed mood or anhedonia (see chart).

A careful review to determine if there was ill health before the onset of symptoms is the key to resolving the differential diagnosis of somatoform and somatization disorders. A long-standing history of frequent medical investigation and treatment for unexplained physical symptoms, preoccupation with unusual physical explanations of illness and persistent rejection of the potential relevance of pyschosocial factors may suggest the diagnosis.

Question: What symptoms would be described as key features of CFS, if the symptoms were to last more than six months?

A)        An acute viral syndrome described as flu-like but with an extraordinary degree of myalgia.

B)        Low-grade fever and fatigue.

C)        Arthralgia of the large joints and hands.

D)        Sore throat and tender lymph nodes in the neck and axillae.

E)         Vertigo

Answer: A, B, C and D. An acute viral syndrome as described in A may trigger CFS. The immune system, which normally gears down after an infection has been eliminated, remains activated instead. This results in unusually high concentrations of immune activating factors — some of which are known at high doses to cause fatigue — in the blood stream.

CFS is described as chronic persistent fatigue and the presence of four of eight symptom criteria, after other medical and/or psychiatric reasons have been excluded. Low-grade fever and fatigue lasting more than six months would suggest this diagnosis.

Arthralgia can occur in many different diseases. Osteoarthritis must be ruled out; rheumatoid arthritis, lupus, inflammatory bowel disease, hepatitis B and C, and rubella also may present with arthralgia.

Sore throat and tender axillary and/or cervical nodes are common complaints of patients with CFS and are generally associated with non-exudative pharyngitis. Twenty-eight percent of CFS patients have splenomegaly by ultrasound. The finding of splenomegaly, hepatomegaly or diffuse lymphadenopathy, or persistent fever greater than 101 degrees should trigger a diagnostic evaluation for other causes, e.g., malignancy, HIV infection or lupus.

Vertigo is not typical of CFS patients, but must be distinguished from lightheadedness or dizziness, which may be associated with the illness.

Differential Diagnosis of Fatigue

Findings:             Reduced muscle strength at rest

Etiology:            Muscle weakness (e.g., myopathy, polymyositis)

Findings:            Physical and mental fatigue at rest

Etiology:            Neuromuscular fatigability (e.g., myasthenia gravis)

Findings:            Lack of motivation to commence                             tasks and lack of pleasure from tasks                          undertaken

Etiology:            Anhendonia (e.g., major depression)

Findings:            Daytime sleepiness or short sleep latency

Etiology:            Somnolence (e.g., sleep apnea, narcolepsy)

Findings:            Breathlessness at rest or on exercise

Etiology:            Dyspnea and weakness (e.g., cardiac failure, airflow limitation, anemia)

Findings:            Muscle pain, joint pain, fever, malaise

Etiology:            Inflammation (e.g., lupus)

Infection (e.g., influenze)