Q- A 55-year-old man presents to his physician complaining of sinusitis, chest pain, and productive cough for 2 weeks. His sputum is mixed with blood. He also has had pain and swelling of his hands and feet for 3 months. On examination, he has synovitis of the proximal interphalangeal joints of both hands. His laboratory tests reveal anemia, elevated ESR, elevated creatinine, and positive c-ANCA. Urinalysis shows red blood casts and proteinuria. Chest x-ray shows multiple nodules in both lungs.
What is the most likely diagnosis?
A- Acute glomerulonephritis
B- Miliary tuberculosis
C- Wegener granulomatosis
D- Rheumatoid arthritis
E- Systemic lupus erythematosus
Answer
The constellation of symptoms and findings described suggests a systemic autoimmune condition with involvement of multiple organs.
The presence of sinusitis, chest pain, productive cough with hemoptysis, and multiple nodules in both lungs on chest x-ray suggests pulmonary involvement, which could be due to granulomatous inflammation seen in certain autoimmune diseases.
The pain and swelling of hands and feet along with synovitis of the proximal interphalangeal joints are suggestive of an inflammatory arthritis, which can be seen in various autoimmune diseases.
The laboratory findings of anemia, elevated ESR (erythrocyte sedimentation rate), elevated creatinine, positive c-ANCA (anti-neutrophil cytoplasmic antibody), red blood casts, and proteinuria indicate renal involvement, likely secondary to Wegener granulomatosis.
Wegener granulomatosis, now known as granulomatosis with polyangiitis (GPA), is a systemic autoimmune disorder characterized by necrotizing granulomatous inflammation affecting the upper and lower respiratory tract, as well as small- to medium-sized blood vessels (vasculitis). It commonly presents with sinusitis, pulmonary nodules, hemoptysis, and renal involvement (glomerulonephritis). The presence of c-ANCA is a characteristic serologic finding in GPA. Additionally, joint involvement can occur in GPA, manifesting as arthritis or synovitis.
The correct answer is C
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