The Kidneys in Systemic Disease Flashcards
What organ receives the most blood flow per unit volume?
Kidneys
What are the different things that can happen to proteins at the glomerular?
Glomerular may filter proteins which are then reabsorbed by the tubule epithelial cells:
Or may trap proteins or immune complexes
What are some systemic diseases that affect the kidney?
- Diabetes mellitus
- CVD
- Cardiac failure
- Atheroembolism
- Hypertension
- Atherosclerosis
- Infection
- Sepsis
- Post-infectious GN
- Infective endocarditis
- Inflammation in blood vessels
- SLE
- Vasculitis
- Scleroderma and other connective tissue diseases
- Cryoglobulinaemia
- HUS/TTP
- Myeloma
- Amyloidosis
What are some drugs that affect the kidneys?
- Aminoglycosides
- ACE inhibitors
- Penicillamine, gold
- NSAIDs
- Radiocontrast
Describe the natural history of diabetic nephropathy?
- Silent sub-clinical phase
- Hyperfiltration
- Increased GFR
- Microalbuminuria (20-200ug/d)
- Clinical nephropathy (proteinuria > 0.5g/d)
- Established renal failure
So causes development of proteinuria and decline in GFR
Describe the long term risk of diabetic nephropathy with type 1 and 2 diabetes?
- Type 1 diabetes
- 4% develop nephropathy within 10 years
- 25% develop nephropathy within 25 years
- Type 2 diabetes
- 10% develop nephropathy within 5 years
- 30% develop nephropathy within 20 years
- 30% of those with diabetic nephropathy will progress to ESRF
What percentage of people with diabetic nephropathy will progress to ESRF?
30%
What is the single commonest cause of ESRF?
Diabetes
Is the incidence of ESRF due to diabetes increasing or decreasing?
Increasing
Out of type 1 and 2 diabetes, who is at the greatest risk of diabetic nephropathy?
Equal risk
What is increasing proteinuria usually associated with in terms of GFR?
Declinging GFR
What is chronic kidney disease classified based on?
Classification is based on kidney function (GFR)
What classification system does CKD use?
Uses NKF K/DOQI classification system
What is stage 1 CKD?
What is stage 2 CKD?
What is stage 3 CKD?
What is stage 4 CKD?
What is stage 5 CKD?
What is the relationship between CKD and CVD?
What is the commonest cause of renal failure in older patients?
Commonest cause of renal failure in older patients is reno-vascular disease:
- Atheroembolic disease
- Eosinophilia
- Peripheral skin lesion
- Warfarin therapy
- Vascular procedures
What is vasculitis?
Is inflammatory reaction in the wall of any blood vessel
What is vasculitis defined by?
Defined by size of vessels involved
Explain the nomenclature of vasculitis?
- Aorta/large artery
- Takayasu arteritis
- Giant cell arteritis
- Medium artery
- Polyarteritis nodosa
- Kawasaki disease
- Small vessel
- Wegener’s granulomatosis
- Granulomatous inflammation in respiratory tract
- Focal necrotising glomerulonephritis with crescents
- Slightly more common in males
- Affects all age groups, most common 40-60 years
- Upper respiratory tract symptoms
- Epistaxis, nasal deformity, sinusitis, deafness
- Lower respiratory tract symptoms
- Cough, dyspnoea, haemoptysis
- Pulmonary haemorrhage
- Other organs
- Kidney – glomerulonephritis
- Joints – arthralgia, myalgia
- Eyes – scleritis
- Heart – pericarditis
- Systemic – fever, weight loss, vasculitic skin rash
- Microscopic polyarteritis
- Can present with systemic disease, renal and pulmonary involvement
- More commonly renal limited disease
- Churg-Strauss syndrome
- Wegener’s granulomatosis
What is vasculitis of aorta/large artery called?
- Takayasu arteritis
- Giant cell arteritis
What is vasculitis of a medium artery called?
- Polyarteritis nodosa
- Kawasaki disease
What is vasculitis of a small vessel called?
Wegener’s granulomatosis
Microscopic polyarteritis
Churg-Strauss syndrome
What is the presentation of Wegener’s granulomatosis?
- Upper respiratory tract symptoms
- Epistaxis, nasal deformity, sinusitis, deafness
- Lower respiratory tract symptoms
- Cough, dyspnoea, haemoptysis
- Pulmonary haemorrhage
- Other organs
- Kidney – glomerulonephritis
- Joints – arthralgia, myalgia
- Eyes – scleritis
- Heart – pericarditis
- Systemic – fever, weight loss, vasculitic skin rash
What investigations are used for diagnosis in vasculitis?
- Urine
- Blood/protein
- Renal function
- Raised urea/creatinine
- Biochemistry
- Raised alk phos, CRP, low albumin
- Haematology
- Anaemia, thrombocytosis, leucocytosis
- Immunology
- Hyperglobulinaemia
- Positive antineutrophil cytoplasmic antibodies (ANCA)
- Renal biopsy
What are the different kinds of ANCA?
- C-ANCA (cytoplasmic)
- P-ANCA (perinuclear)
What is C-ANCA and what is P-ANCA associated with?
C-ANCA, Wegener’s granulomatosis
P-ANCA, microscopic polyarteritis
What does infective endocarditis result from?
Result of bacterial (or fungal) infection on cardiac valves
What are the typical infections that cause endocarditis?
- Staphylococcus aureus
- Viridans streoptococci
- Enterococci
What does infective endocarditis lead to in terms of the urinary system?
Leads to glomerulonephritis with or without small vessel vasculitis due to immune complex formation
What is renal involvement in infective endocarditis suggested by?
- Abnormal urea/creatinine
- Haematuria, red cell casts
- Reduced complement levels
Can renal disease due to infective endocarditis be recovered?
Renal disease should recover when underlying infection is treated
What is multiple myeloma?
A monoclonal proliferation of plasma cells producing an excess of immunoglobulins and light chains
In what age group is multiple myeloma common in?
Elderly
What are the clinical features of multiple myeloma?
- Markedly elevated ESR
- Anaemia
- Weight loss
- Fractures
- Infections
- Back pain/cord compression
What is multiple myeloma diagnosed by?
- Bone marrow aspirate >10% clonal plasma cells
- Serum paraprotein with or without immunoparesis
- Urinary bence-jones protein (BJP)
- Skeletal survery
What renal failure is seen in myeloma?
- Cast nephropathy
- Light chain nephropathy
- Tubular basement membrane (TBM) Ig deposition
- Amyloidosis
- Deposition of abnormal fibrillary proteins that persist
- Primary/secondary
- Hypercalcaemia
- Hyperuricaemia
What are the typical symptoms of renal involvement in systemic disease?
- Fever
- Malaise
- Weight loss
- Arthralgia
- Myalgia
- Skin rash (vasculitic)
- Gritty eyes
- Breathlessness
- Haemoptysis
- Epistaxis
- Haematuria
- Oedema
What are the typical signs of renal involvement in systemic disease?
- Hands
- Spinter haemorrhages
- Purpura
- Raynaud’s
- Face
- Scleritis
- Uveitis
- Nasal cartilage deformity
- Retinal vasculitis
- Hypertensive retinopathy
- Skin
- Vasculitic rash
- Scleroderma
- CVS
- Hypertension
- Murmur
- Chest
- Crepitations
- Haemoptysis
- Locomotor
- Joint swelling
- Tenderness
- CNS
- Stroke
- Encephalopathy
What investigations should be done for renal involvement in systemic disease?
Initial investigations:
- Urine
- Blood/protein on urinalysis
- Microscopy – red cell casts
- Blood
- Elevated urea/creatinine
- Raised CRP
- Thrombocytosis, anaemia
- Raised alkaline phosphatase
Further investigations:
- Bloods
- ANCA (anti-MPO/anti-PR3 antibodies)
- ANA, dsDNA antibodies
- Complement levels C3, C4
- Blood cultures
- Radiology
- CXR
- USS abdomen
- Renal size
- CT thorax
- Pulmonary granulomas, interstitial disease
- Echocardiography
- Biopsy
- Kidney
- Nasal mucosa
- Lung
- Skin
