A 19-year old white female presents in the office with gross-hematuria (tea-colored), mild renal insufficiency and a rash. There is a 6 week antecedent history of nausea and vomiting, abdominal pain, non-specific achiness of joints and a lower extremity diffuse rash. She says that she has taken ibuprofen intermittently for the past 5 weeks. The patient is prescribed topical hydrocortisone. 2 days later she presents to the emergency department and a diagnosis of a“viral syndrome” is made and she is treated with Compazine for nausea. She returns to her PCP with worsening rash and is now admitted to the hospital. A nephrologist is consulted. The physical examination shows a blood pressure of 184/80 mmHG, temperature of 98.4oF, heart rate of 75 beats per minute and 2+ pitting edema. The patient has non-specific abdominal tenderness and a rash on her lower extremities (picture shown). The patient declines a skin biopsy, and is treated with prednisone 20 mg per day. Urinalysis shows: 2-3+ hematuria and 4+ albuminuria on dipstick. The urine sediment shows many dysmorphic red cells and 1-2 red cell casts. Her laboratory data shows a BUN of 31 mg/dL, creatinine of 1.6 mg/dL, hematocrit 30.5. The patient’s work-up shows normal complements, a negative ANA and anti-double stranded DNA antibody level, and a negative ANCA. The most likely diagnosis is?
A.) Lupus nephritis
B.) Mixed essential cryoglobulinemia
C.) Henoch-Schonlein nephritis
D.) Acute Interstitial nephritis
E.) Anti-GBM nephritis
Answer next quiz
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The answer from the Case from 8/29/11 was D: "Anti-GBM Nephritis".
Here is a thumb-nail on anti-GBM nephritis:
Anti-GBM nephritis is caused by circulating Anti-GBM antibody directed against the NC1 domain of the alpha-3 chain of type IV collagen (highly expressed in the glomerular basement membrane and alveoli). Key features clinically:
- acute or rapidly progressive glomerulonephritis w/ crescent formation
- typically presents with the syndrome of glomerulonephritis and pulmonary hemorrhage
- may present with glomerulonephritis alone
Renal Pathology (light microscopy and immunofluoresence are shown below:
60 to 70 percent of patients have pulmonary involvement:
- Risk factors include: underlying pulmonary injury – smoking, infection, cocaine inhalation, hydrocarbon exposure
- The clinical presentation for the pulmonary presentation include:
- alveolar hemorrhage
- shortness of breath
- cough, sometimes overt hemoptysis and iron deficiency anemia
- pulmonary infiltrates on chest x-ray
- increased carbon monoxide diffusing capacity
