Vasculitis and Kidney Damage Quiz

System Vasculitis and Kidney Damage

• System vasculitis, connective tissue diseases, and kidney damage are interconnected.
• Kidney amyloidosis is a concern.
• Thrombotic microangiopathies, paraproteinemic diseases, and myeloma are also related.

Primary Glomerulopathies

• Acute proliferative glomerulonephritis (post-infectious and other types) are addressed.
• Rapidly progressive glomerulonephritis, membranous glomerulopathy, minimal-change disease, focal segmental glomerulosclerosis, and membranoproliferative glomerulonephritis, IgA nephropathy are all specific types.
• Chronic glomerulonephritis is also mentioned.

Systemic Diseases with Glomerular Involvement

• Systemic lupus erythematosus, diabetes mellitus, and amyloidosis are discussed.
• Goodpasture syndrome, microscopic polyangiitis/polyangiitis, Wegener granulomatosis, Henoch-Schönlein purpura, and bacterial endocarditis are also mentioned.
• Hereditary disorders like Alport syndrome, thin basement membrane disease, and Fabry disease are included.

Lupus Nephritis (LN)

• Lupus nephritis (LN) is a frequent and potentially serious complication of systemic lupus erythematosus (SLE).
• Renal involvement worsens morbidity and mortality rates in lupus.
• Approximately 25% to 50% of unselected lupus patients have clinical renal disease at disease onset, and up to 60% of adults with SLE develop renal disease during their lifetime.
• Renal involvement in SLE is defined by persistent proteinuria exceeding 500 mg daily or the presence of cellular casts.
• Glomerular and vascular damage is potentiated by hypertension and a thrombotic microangiopathy.

Histopathologic Patterns in LN

• Renal biopsies in LN can reveal a number of histopathologic patterns.
• Overlapping patterns and/or histologic progression can occur.
• The World Health Organization (WHO) has a classification system for biopsies.
• Biopsies are classified into six categories based on glomerular changes under light microscopy. (See table 12-1 for details)

Lupus Nephritis (LN) Classification

• The WHO 2003 classification breaks down lupus nephritis biopsies into six classes based on light microscopy findings.
• Each class has a specific description as to glomerular changes. (See table 12-1 and 12-2 for detailed descriptions.)

Immunopathologic Findings in SLE

• Abnormal autoantibody production is a hallmark of SLE.
• Antinuclear antibodies (ANAs), and especially anti-DNA, are criteria for SLE and help monitor the course of the disease.
• Anti-dsDNA, a more targeted marker for SLE, is more specific, but less sensitive than ANA.
• Anti-Sm, anti-RNP, anti-Ro/serum amyloid A, and anti-La/SSB are other autoantibodies present in lupus but are not as predictive of renal involvement.

Pregnancy and Lupus Nephritis

• Pregnancy in patients with LN has been associated with worsening of renal function.
• Risk factors include active disease in the previous 6 months, hypertension, proteinuria, and baseline renal impairment.
• The risk of fetal loss is elevated, potentially exceeding 50%.
• High doses of corticosteroids and azathioprine are sometimes used, although mycophenolate and cyclophosphamide are contraindicated in pregnancy.

Renal Disease from Lupus Nephritis

• Patients diagnosed with LN, who develop end-stage renal disease have remission of their extrarenal manifestations as well as serological activity.
• Renal transplant programs may allow patients to have a dialysis period (3 to 12 months) to allow the disease to calm down before a transplant to improve the likelihood of the transplant being successful.

Treatment Options for Lupus Nephritis

• Treatment options for lupus nephritis are stratified by International Society of Nephrology classification and phase of therapy.
• Specific induction and maintenance phases of therapy exist.
• Prescribed medications, including but not limited to steroids, mycophenolate mofetil, cyclophosphamide, azathioprine and other immune suppressants are included for different classes of lupus nephritis.

Mixed Connective Tissue Disease (MCTD)

• MCTD shares overlapping characteristics with SLE, scleroderma, and polymyositis.
• A high ANA titer with speckled pattern and specific ribonuclease-sensitive ENA antibodies are often present in MCTD patients.
• Renal involvement is often mild to minimal.

Primary Systemic Vasculitides

• Various types of primary systemic vasculitis are illustrated, including small, medium, and large vessel vasculitides.
• Distinct descriptions of each exist, including clinical characteristics and organ involvement. (Tables 1 and 2 display various forms.)

Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis (AAV)

• AAV is a group of autoimmune disorders (GPA, MPA, and EGPA).
• It involves inflammation of small blood vessels.
• Diagnosis relies on ANCA testing, and clinical presentations.
• Treatment includes immunosuppressants like glucocorticoids, cyclophosphamide, and other agents.

Thrombotic Microangiopathy (TMA)

• TMA is a group of disorders characterized by microvascular damage, thrombosis, and hemolysis.
• It includes conditions like HUS and TTP.
• Hallmarks include thrombocytopenia, hemolytic anemia, and schistocytes on blood smears.
• Underlying factors (infections, medications, etc.) can trigger TMA.

Hemolytic Uremic Syndrome (HUS)

• HUS is a type of TMA, often triggered by shiga toxin-producing E.coli (STEC) infection.
• It leads to acute kidney failure, neurologic symptoms, and potentially serious complications.
• Diagnosis requires evaluation of ADAMTS13 levels and testing for STEC to distinguish from atypical HUS.

Amyloidosis

• Amyloidosis involves the abnormal deposition of protein fibrils in various organs.
• Primary (AL) amyloidosis results from immunoglobulin light chain deposition from plasma cells, while secondary (AA) amyloidosis develops in chronic inflammatory conditions.
• Diagnostics frequently involve tissue biopsies.

Waldenstrom Macroglobulinemia

• Waldenstrom macroglobulinemia, a rare blood cancer, features the accumulation of IgM monoclonal proteins.
• It can lead to hyperviscosity syndrome and other symptoms (fatigue, bleeding, neuropathy, etc).
• Treatment focuses on targeting the underlying lymphoproliferative disease and/or addressing hyperviscosity symptoms.

This quiz covers the interconnections between systemic vasculitis and various forms of kidney damage, including conditions like amyloidosis and glomerulonephritis. It explores both primary glomerulopathies and systemic diseases that affect the kidneys, such as lupus and diabetic nephropathy.