The Kidney in Systemic Disease Flashcards
What organ receives more blood flow per unit volume than any other organ in the body?
Kidneys
What can the glomeruli do to proteins?
- The glomeruli may filter proteins which are then reabsorbed by the tubule epithelial cells
- The glomeruli may trap proteins or immune complexes
What types of systemic disease can affect the kidneys?
Diabetes mellitus
Cardiovascular disease
- 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 drugs can affect the kidneys?
- Aminoglycosides
- ACEI
- Penicillamine
- Gold
- NSAIDs
- Radiocontrast
Describe the natural history of diabetic nephropathy.
- Silent sub-clinical phase. Hyper filtration. Increased GFR
- Microalbuminaemia [20-200ug/d]
- Clinical nephropathy [proteinuria >0.5g/d]
- Established renal failure
What percentage of those with diabetic nephropathy will progress to ESRF?
30%
What is the long term risk of nephropathy for T1DM and T2DM patients?
- 4% with Type 1 DM will develop nephropathy within 10 years
- 25% with Type 1 DM will develop nephropathy within 25 years
- 10% with Type 2 DM will have nephropathy by 5 years
- 30% with Type 2 DM will have nephropathy by 20 years
What is the commonest single cause of ESRF?
Diabetic nephropathy
What is increasing proteinuria usually associated with?
Declining GFR
What is classification of chronic kidney disease based on?
Kidney function
What classification system is used for chronic kidney disease?
NKF K/DOQI classification system
What are the 5 stages of chronic kidney disease?
- 1 Kidney damage/ normal or high GFR (GFR >90)
- 2 Kidney damage/ mild reduction in GFR (GFR 60-89)
- 3 Moderately impaired (GFR 30-59)
- 4 Severely impaired (15-29)
- 5 Advanced or on dialysis (GFR<15)
What is a common cause of renal failure in older patients?
Renal vascular disease
What is indicative of atheroembolic disease?
- Eosinophilia
- Peripheral skin lesions
- Warfarin therapy
- Vascular procedures
What is vasculitis?
Inflammatory reaction in the wall of any blood vessel
How is vasculitis defined?
By the size of vessel involved
What can vasculitis affect?
- Can affect single or multiple organs
- Wide spectrum of clinical presentations
What types of vasculitis affect large arteries/aorta?
- Takayasu arteritis
- Giant cell arteritis
What kind of vasculitis affects medium arteries?
- Polyarteritis nodosa
- Kawasaki disease
What kind of vasculitis affects small vessels?
- Wegener’s granulomatosis
- Microscopic polyarteritis
- Churg-Strauss syndrome
Who does Wegener’s granulomatosis affect?
- Slightly more common in males
- Affects all age groups, most common 40-60 y
What is Wegener’s granulmatosis?
- Granulomatous inflammation in respiratory tract
- Focal necrotising glomerulonephritis with crescents
How can Wegener’s granulomatosis present in the upper respiratory tract?
- Epitaxis
- Nasal deformity
- Sinusitis
- Deafness
How can Wegener’s granulamosis present in the lower respiratory tract?
- Cough
- Dyspnoea
- Haemoptysis
- Pulmonary haemorrhage
How can Wegener’s granulomatosis present in systems other than the respiratory system?
Kidney
-Glomerulonephritis
Joints
- Arthralgia
- Myalgia
Eyes
Scleritis
Heart
-Pericarditis
Systemic
- Fever
- Weight loss
- Vasculitis skin rash
What condition has a similar clinical spectrum to Wegener’s granulomatosis?
Microscopic polyarteritis
How can microscopic polyarteritis present?
- Can present with systemic disease, renal and pulmonary involvement
- More commonly renal limited disease
How is vasculitis diagnosed?
Urine
-Blood/protein
Renal function
-Raised urea/creatinine
Biochemistry
-Raised alk phos, CRP, low albumin
Haematology
-Anaemia, thrombocytosis, leukocytosis
Immunology
-Hyperglobulinaemia, Positive ANCA
Renal biopsy
What is C-ANCA?
Cytoplasmic
What is P-ANCA?
Perinuclear
What antibodies are associated with P-ANCA?
Myeloperoxidase
What antibodies are associated with C-ANCA?
Proteinase-3
Give an example of when ANCA can give a false positive.
IBD
What form of ANCA is associated with microscopic polyarteritis?
P-ANCA
What form of ANCA is associated with Wegener’s granulomatosis?
> 90% C-ANCA
What is endocarditis a result of?
A bacterial (or fungal) infection on cardiac valves
What are the typical infections associated with infective endocarditis?
- Staphlococcus aureus
- Viridans streptococci
- Enterococci
What can infective endocarditis lead to?
Leads to glomerulonephritis ± small vessel vasculitis due to immune complex formation
In infective endocarditis, what is renal involvement suggested by?
- Abnormal urea/creatinine
- Haematuria, red cell casts
- Reduced complement levels
When should renal disease get better in infective endocarditis?
Renal disease should recover when underlying infection treated
What is multiple myeloma?
A monoclonal proliferation of plasma cells producing an excess of immunoglobulins and light chains
Who 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
How is multiple myeloma diagnosed?
- Bone marrow aspirate >10% clonal plasma cells
- Serum paraprotein ± immunoparesis
- Urinary Bence-Jones protein (BJP)
- Skeletal survey - lytic lesions
What can cause renal failure in myeloma?
- Cast nephropathy - ‘myeloma kidney’
- Light chain nephropathy
- Amyloidosis
- Hypercalcaemia
- Hyperuricaemia
What is there deposition of in light chain disease?
TBM Ig deposition
What is there deposition of in amyloid?
Deposition of abnormal fibrillary proteins that persist. [AA /AL
What history may suggest a systemic disease with renal involvement?
- Fever
- Malaise
- Weight loss
- Arthralgia
- Myalgia
- Skin rash (vasculitis)
- Gritty eyes
- Breathlessness
- Haemoptysis
- Epistaxis
- Haematuria
- Oedema
How common is systemic disease with renal involvement?
Relatively rare but frequently missed
What does the outcome of systemic disease with renal involvement depend on?
Prompt diagnosis and treatment
What signs may be present on the hands in systemic disease with renal involvement?
- Splinter haemorrhages
- Purpura
- Raynaud’s
What signs may be present on the face in systemic disease with renal involvement?
- Scleritis
- Uveitis
- Nasal cartilage deformity
- Retinal vasculitis
- Hypertensive retinopathy
What signs may be present on the skin in systemic disease with renal involvement?
- Vasculitic rash
- Scleroderma
What CVS signs may be present in systemic disease with renal involvement?
- Hypertension
- Murmur
What chest signs may be present in systemic disease with renal involvement?
- Crepitation’s
- Haemoptysis
What locomotor signs may be present in systemic disease with renal involvement?
- Joint welling
- Tenderness
What CNS signs may be present in systemic disease with renal involvement?
- Stroke
- Encephalopathy
What initial investigations should be carried out for systemic disease with renal involvement?
Urine
- Blood/protein on urinalysis
- Microscopy - red cell casts
FBCs
- Elevated urea/creatinine
- Raised CRP
- Thrombocytosis, anaemia
- Raised alkaline phosphatase
What can further investigation of the blood show in systemic disease with renal involvement?
- ANCA (anti-MPO/anti-PR3 antibodies)
- ANA, dsDNA antibodies
- Complement levels C3, C4
- Blood cultures
- Immunoglobulins and electrophoresis
What radiological investigations could be carried out for investigating systemic disease with renal involvement?
- CXR
- USS abdomen (Renal size)
- CT thorax (Pulmonary granulomas, interstitital disease)
- Echocardiography
What biopsies may you consider taking in systemic disease with renal involvement?
- Kidney
- Nasal mucosa
- Lung
- Skin
