The Kidney in Systemic Disease I Flashcards
What are some vascular injury syndromes?
- ANCA-associated glomerulonephritis
- Thrombotic microangiopathy
- Lupus nephritis
- Scleroderma
Describe how renal disease presents in medium vessel diseases like PAN?
You see renal infarcts due to distal glomerular ischemia that causes a decrease in GFR but is not associated with glomerular inflammation with RBC casts (usually ANCA negative)
Describe how renal disease presents in SMALL vessel diseases like Wegener’s and microscopic polyangiitis?
focal necrotizing lesions with crescent formation that have active urinary sediment and rapid progression of kidney failure (usually ANCA positive)
What vessels does PAN affect?
systemic segmental, necrotizing vasculiitis of medium-sized muscular arteries, not veins
When does PAN usually present?
most commonly in middle-aged or older adults
What causes PAN?
Usually idiopathic, although may be associated with Hep B, Hep C, and hairy cell leukemia
What is pauci-immune glomerulonephritis?
Refers to negative immunofluorescence studies usually in the setting of crescentic glomerulonephritis
What is pauci-immune glomerulonephritis typically associated with?
ANCAs with extrarenal findings (arthritis, athralgias, myalgias, fatigue)
ANCA titers may not always parallel disease activity
Which has diffuse cytoplasmic reactivity, C-ANCA (PR3) or P-ANCA (MPO)?
C-ANCA
What does a positive C-ANCA (PR3) suggest?
Positivity strongly suggests Granulomatosis with polyangiitis (AKA Wegener’s granulomatosis)
can be P-ANCA positive or C-ANCA neg however
Which has perinuclear cytoplasmic reactivity, C-ANCA (PR3) or P-ANCA (MPO)?
P-ANCA
Nonmyeloperoxidase P-ANCA has been detected in what diseases?
- sclerosing cholangitis, -ulcerative colitis, and
- Crohn’s disease
What are the two sinopulmonary renal syndrome?
Goodpastures and Wegener’s
What is the difference in the presentation of Wegener’s and Goodpastures?
At presentation, patients with Goodpasture’s disease will likely have significant renal dysfunction while it is much more mild in Wegener’s
How does Wegener’s present?
- cough, dyspnea, hemopytsis
- pulmonary infiltrates on x-ray
- fever, weight loss, skin lesions
How is Wegener’s treated?
lots of immunosuppression- 3 doses of cyclophosphamide based regimens, steroids, and plasmapheresis depending on severity of disease
mortality is 80-90% if left untreated
Does Wegener’s relapse often?
Yes, about 25-50% will relapse within 3-5 yrs
HUS is a thrombotic microangiopathic disease associated with what clinical triad?
- hemolytic anemia (schistocytes)
- renal dysfunction
- thrombocytopenia
TTP is also a thrombotic microangiopathic disease associated with what clinical pentad?
- Fever
- Hemolytic anemia
- Thrombocytopenia
- Renal dysfunction
- Neurologic dysfunction (eg. seizures)
need to treat early with plasmapheresis
What does thrombotic microangiopathy cause?
loss of thromboresistance by endothelial cells leading to platelet activation and deposition of platelets and fibrin thrombi in the lumen of affected vessels giving the vessels an ‘onionskin’ appearance (not-specific- can see in malignant HTN)
What things is HUS associated with?
- verotoxin producing E. Coli H7:O157
- chemo (cyclosporine, gemcitabine, bleomycin /cisplatinum)
- radiation
What causes TTP?
Increased levels of von Willebrand factor multimers due to ADAMTS 13 mutation may directly enhance platelet aggregation
TTP also occurs in the setting of autoimmune diseases (antiphospholipid syndrome) associated with autoantibodies to inhibitors of platelet aggregation
How can you clinically differentiate between TMA vs DIC?
Prothrombin time and partial thromboplastin times are normal in TMA but prolonged in DIC
Case. A 27-year-old AA woman with a 10-year history of systemic lupus erythematosus (SLE) but no previous history of renal disease presents with new onset of hematuria and proteinuria.
Previous manifestations of SLE included pericarditis, alopecia, a malar rash, and arthralgias.
Medications include prednisone 5 mg/day and hydroxychloroquine 200 mg/day.
Physical examination reveals a BP of 122/76, an erythematous facial rash, and no edema.
Laboratory results revealed serum creatinine 0.9 mg/dl, spot urine protein to creatinine ratio 2.9, serum albumin 2.8 g/dl, white blood cell count 2400/L, hemoglobin 10.5 g/dl, platelet count 127k/L, anti-nuclear antibody (ANA) titer 1:1280, anti-double stranded DNA antibody 500 IU/ml, low C3 and C4 complement levels.
Urine sediment showed dysmorphic RBCs, no significant white blood cells, and no cellular casts.
The kidneys measure 12.1 and 11.5 cm by ultrasound.
Renal biopsy was performed.
SLE
