Rheumatology

A 3-year-old boy with suspected systemic-onset JRA develops tachycardia and dyspnea on the fifth day of hospitalization. He complains that his chest hurts. Auscultation of the heart reveals a “friction rub” sound. The most likely diagnosis is:
A. Heart failure.
B. Pneumonia.
C. Asthma.
D. Pericarditis.
E. Mitral valve prolapse.

D. A friction rub is characteristic of pericarditis.

A 17-year-old girl comes to the office complaining of persistent joint tenderness for the previous 2 months that has limited her summer job of lifeguarding at the neighborhood pool. In the morning, she awakens with bilateral knee pain and swelling and right-hand pain. The pain eases during the day but never com-pletely resolves. Nonsteroidal anti-inflammatory medications help slightly. She also wants a good “face cream” because she reports that the sun exposure at the pool “has worsened her acne.” On physical examination you notice facial erythema in¬volving the cheeks and nasolabial folds. She has several ulcers in her mouth that she calls cold sores, bilateral knee effusions, and her distal interphalangeal joints on her right hand are swollen and tender. Her liver is palpable 3 cm below the costal margin. You perform a urinalysis and find microscopic hema¬turia and proteinuria. What is the likely cause of this young woman’s arthritis?
A. Juvenile rheumatoid arthritis
B. Osteoarthritis
C. Postinfectious arthritis
D. Lyme disease
E. Systemic lupus erythematosus

E. Systemic lupus erythematosus affects more women than men and nephritis is one of the more common features seen at pre¬sentation. Her rash, photosensitivity, oral ulcers, hepatomegaly, arthritis, and nephritis combine to make this a likely diagnosis. A positive antinuclear antibody and low C3 and C4 would help to confirm the diagnosis.

A l4-year-old girl presents with right knee pain. She states that the pain has occurred intermittently over the past 2 months and is not associated with exercise. Her mother has questions about sunscreen use, as the patient had severe “sunburn” on her face across her cheeks and nose 3 weeks ago. The patient also notes that she has not been feeling well and is increasingly tired re¬cently. Upon examination her knee appears normal and has good range of motion and her gait is normal the next step in management is to:
A. Prescribe ibuprofen and recommend daily sunscreen use.
B. Obtain radiographs of the affected knee.
C. Obtain further history, specifically regarding fever, weight loss, other rashes, and other arthritis.
D. Recommend the use of a knee immobilizer.
E. Arrange for an emergent orthopedic consultation for evalu¬ation of possible slipped capital femoral epiphysis.

C. This patient has complaints of joint pain and malaise and had a facial rash consistent with the malar rash found in systemic lu¬pus erythematosus (SLE). The next step is to obtain a more de¬tailed history of other signs and symptoms of autoimmune dis¬ease, medication use (drug induced SLE), and travel history (tick exposure for Lyme disease).

A mother brings to the clinic her 4-year-old son who began complaining of right knee pain 2 weeks ago, is limping slightly, is fatigued, and has had a fever to 100.4 F (38°C). Which of the following is the most important diagnostic laboratory test to perform?
A. Epstein-Barr virus titer
B. Sedimentation rate
C. Antinuclear antibodies
D. Complete blood count (CBC) with differential and platelets
E. Rheumatoid factor

D. This child has symptoms of JRA as well as leukemia. The CBC with differential and platelets is the best initial screening test. The leukocyte count is normal to increased in JRA and the platelet count is normal to increased; there are no blast cells. Frequently, blast cells are found on the peripheral smear in chil¬dren with ALL. The child in the question may ultimately require a bone marrow aspiration.

A 5-year-old girl is referred to a pediatric rheumatologist with a 4-week history of mild swelling and decreased range of motion in the left knee and right elbow. She is afebrile and appears oth¬erwise well. The procedure most likely to be helpful in the di¬agnosis of her condition is:
A. Arthrocentesis
B. A complete blood count
C. A computerized tomography (CT) scan of the involved joints.
D. A slit-lamp examination of both eyes.
E. A bone scan.

D. Slit-lamp findings consistent with JRA are likely to be most helpful (most specific). The other choices, and a variety of other tests such as an erythrocyte sedimentation rate, are also helpful but are often nonspecific.