08-14-2010, 09:11 PM
A 62-year-old man is evaluated in the emergency department for a 1-month history of nonproductive cough, progressive dyspnea on exertion, fever, arthritis, and weakness. He has had increasing difficulty rising from a chair, climbing stairs, and holding his arms up to comb his hair. For the past week, he has noticed pain and color changes of his digits when exposed to the cold. His medical history is otherwise unremarkable, and he takes no medications.
On physical examination, temperature is 38.7 °C (101.6 °F), blood pressure is 148/88 mm Hg, pulse rate is 100/min, and respiration rate is 34/min. Pulse oximetry shows 92% oxygen saturation with the patient breathing 2 L/min of supplemental oxygen. There is no jugular venous distension. Cardiac examination reveals normal heart sounds without extra sounds, murmurs, or rubs. On pulmonary examination, late bilateral fine crackles are noted over the lower half of the lung fields. The sides of the fingers appear rough and cracked. He has tenderness and synovial thickening involving the wrists and the second and third metacarpophalangeal joints. Grip strength is intact, but he has evidence of weakness in the muscles of the upper arms and legs and neck flexors.
Laboratory studies:
Hemoglobin 13.8 g/dL (138 g/L)
Leukocyte count 10,600/µL (10.6 × 109/L)
Creatine kinase 5400 U/L
Antinuclear antibodies Titer of 1:640
Anti“double-stranded DNA antibodies Negative
Anti-Smith antibodies Negative
Anti“Scl-70 antibodies Negative
Anti“Jo-1 antibodies Positive
Chest radiograph is shown: http://yfrog.com/mdcaptureklp
Which of the following is the most likely diagnosis?
A-Antisynthetase syndrome
B-Idiopathic pulmonary fibrosis
C-Systemic lupus erythematosus
D-Systemic sclerosis