Glomerular disease

Question 1

Nephritic Syndrome

Answer 1

Disorder of glomerular inflammation, also called glomerulonephritis.

Proteinuria may be present but is usually less than 1.5g per day.

Question 2

History and physical of nephritic syndrome

Answer 2

Classic findings are PHAROH

1) Proteinuria
2) Hematuria
3) Azotemia
4) RBC casts
6) Oliguria
7) HTN

Oliguria, macro/micro hematuria (tea or cola colored urine), HTN and EDEMA

Question 3

Dx of nephritic syndrome

Answer 3

1) UA shows hematuria and possibly mild proteinuria
2) Patients have low GFR with elevated BUN and Cr. Complement, ANA, ANCA, and anti-GBM antibody levels should be measured to determine the underlying cause
3) Renal bx may be useful for histo eval.

Question 4

Tx of nephritic syndrome

Answer 4

1) Treat HTN, fluid overload, and uremia with salt and water restriction, diuretics, and if needed dialysis
2) In some cases, corticosteroids are useful in reducing glomerular inflammation

Question 5

What are 5 examples of nephritic syndromes?

Answer 5

1) Postinfectious glomerulonephritis - IC
2) IgA nephropathy (Berger’s) - IC
3) Wegener’s granulomatosis - Pauci immune
4) Goodpasture’s - Anti GBM
5) Alport’s - Anti GBM

Question 6

Postinfectious glomerulonephritis

Answer 6

Immune complex

Classically associated with recent GAS infection, but can be seen with any infection (usually 2-6w prior)

1) History and exam: Oliguria, edema, HTN, tea or cola urine
2) Labs/Histo: Low serum C3 that normalizes 6-8w after presentation. Increased ASO titer. Lumpy, bumpy immunofluorescence
3) Tx/Prog: Supportive with diuretics to prevent fluid overload. Most patients have full recovery

Question 7

IgA nephropathy

Answer 7

Immune complex

Most common type - typically follows upper respiratory or GI infections. Commonly seen in young males. May be seen in Henoch-Shoenlein purpura.

1) History and exam: Episodic gross hematuria or persistent microscopic hematuria
2) Labs: Normal C3
3) Tx: Glucocorticoids for select patients; ACEIs in patients with proteinuria. Some 20% progress to ESRD

Question 8

Wegener’s granulomatosis

Answer 8

Pauci-immune

Granulomatous inflammation of the respiratory tract and kidney with necrotizing vasculitis

1) History and exam: Fever, weight loss, hematuria, hearing disturbances, respiratory and sinus symptoms. Cavitary pulmonary lesions bleed and lead to hemoptysis.
2) Labs: Presence of c-ANCA (cell mediated immune response). Renal bx shows segmental necrotizing glomerulonephritis with few Ig deposits on IF
3) Tx: High dose steroids and cytotoxic agents. Patients tend to have frequent relapses.

Question 9

Goodpasture’s

Answer 9

AntiGBM

Rapidly progressing glomerulonephritis with pulmonary hemorrhage; peak incidence is in males in their mid-20s

1) History and exam: Hemoptysis*, dyspnea, possible respiratory failure. No upper respiratory tract involvement
2) Labs: Linear anti-GBM deposits on IF. Iron deficiency anemia. Hemosiderin filled macrophages in sputum. Pulmonary infiltrates on CXR
3) Tx: Plasma exchange therapy. Pulsed steroids. May progress to ESRD

Question 10

Alport’s

Answer 10

AntiGBM

Hereditary glomerulonephritis. presents in boys 5-20 years old.

1) History and exam: Asymptomatic hematuria associated with sensorineural deafness* and eye disorders
2) Labs: GBM splitting on EM
3) Tx: Progresses to renal failure. Anti-GBM nephritis may recur after transplant

Question 11

Nephrotic syndrome

Answer 11

Defined as proteinuria (more than 3.5g per day), generalized edema, hypoalbuminemia, and hyperlipidemia.

About one third of all cases result from systemic diseases like DM, SLE or amyloid.

Question 12

Causes of nephrotic syndrome

Answer 12

1) Minimal change disease
2) Focal segmental glomerulosclerosis
3) Membranous nephropathy
4) Diabetic nephropathy
5) Lupus nephritis
6) Renal amyloidosis
7) Membranoproliferative nephropathy

Question 13

History and exam for Nephrotic syndrome

Answer 13

1) Presents with generalized edema and foamy urine. In severe cases, dsypnea and ascites may develop
2) Patients have increased susceptibility to infection as well as predisposition to hypercoagulable states with increased risk of venous thrombosis and pulmonary embolism

Question 14

Dx of nephrotic syndrome

Answer 14

1) UA shows proteinuria and lipiduria
2) Blood chemistry shows low albumin (less than 3) and hyperlipidemia
3) Evaluation should include workup for secondary causes
4) Renal bx is used to definitively diagnose the underlying etiology

Question 15

Tx of nephrotic syndrome

Answer 15

1) Treat with protein and salt restriction, judicious diuretic therapy, and antihyperlipidemics
2) Immunosuppressant meds may be helful for some etiologies
3) ACEIs lower proteinuria and diminish the progression of renal disease in patients with renal scarring
4) Vaccinate with 23-polyvalent pneumococcus vaccine (PPV23) as patients are at higher risk for strep pneumo infection

Question 16

Minimal Change Disease

Answer 16

Most common cause of nephrotic syndrome in children*

Idiopathic etiology; secondary causes include NSAIDs and hematologic malignancies like Hodgkins

1) History and exam: Tendency toward infections and thrombotic events. Sudden onset of edema.
2) Labs: Light microscopy appears normal. EM shows fusion of epithelial foot processes with lipid-laden renal cortices
3) Tx: Steroids. Excellent prognosis

Question 17

Focal Segmental Glomerulosclerosis

Answer 17

Idiopathic, IV drug use, HIV, obesity

1) History and exam: The typical patient is a young african american male with uncontrolled HTN
2) Labs: Microscopic hematuria; bx shows sclerosis in capillary tufts
3) Tx: prednisone, cytotoxic therapy, ACEIs/ARBs to lower proteinuria

Question 18

Membranous nephropathy

Answer 18

The most common nephropathy in white adults*

Secondary causes include solid tumor malignancies (esp in patients over 60) and immune complex disease

1) History and exam: Associated with HBV, syphilis, malaria, and gold
2) Labs: Spike and dome apperance due to granular deposits of IgG and C3 at the basement membrane
3) Tx: Prednisone and cytotoxic therapy for severe disease

Question 19

Diabetic nephropathy

Answer 19

Has 2 characteristic forms: Diffuse hyalinization and nodular glomerulosclerosis (Kimmelstiel-Wilson lesions)

1) History and exam: Patients generally have long-standing, poorly controlled DM with evidence of retinopathy or neuropathy
2) Labs: Thickened GBM; Increased mesangial matrix
3) Tx: Tight control of blood sugar; ACEIs for type 1 DM and ARBs for type 2 DM.

Question 20

Lupus nephritis

Answer 20

Classified as WHO types 1-6. Both nephrotic and nephritic. The severity of renal disease often determines overall prognosis

1) History and exam: Proteinuria or RBCs on UA may be found during evaluation of SLE patients
2) Labs: Mesangial proliferation; subendothelial and/or subepithelial immune complex deposition
3) Tx: prednisone and cytotoxic therapy may slow disease progression

Question 21

Renal amyloidosis

Answer 21

Primary (plasma cell dyscrasia) and secondary (infectious or inflammatory) are the most common

1) History and exam: Patients may have MM or a chronic inflammatory disease (RA or TB)
2) Labs: Nodular glomerulosclerosis; EM reveals amyloid fibrils; apple-green birefringence with Congo Red stain
3) Tx: Prednisone and melphalan. Bone marrow transplant may be used for MM

Question 22

Membranoproliferative nephropathy

Answer 22

Can also be nephritic. Type 1 is associated with HCV, cryoglobulinemia, SLE, and subacute bacterial endocarditis.

1) History and exam: Idiopathic form is present at 8-30 years of age. Slow progression to renal failure
2) Labs: Tram-track double layered BM. Type 1 has subendothelial deposits and mesangial deposits. All 3 types have low serum C3. Type 2 occurs by way of C3 nephritic factor.
3) Tx: Corticosteroids and cytotoxic agents may help