SBI241 - Week 3.docx

**SBI241 -- week 3** **Renal Failure** - *[Acute]* = sudden, sharp decline in renal function, can be reversible - *[Chronic]* = gradual decline in renal function over time = irreversible **Chronic Kidney disease (CKD)** - Irreversible loss of renal function that affects all organ...

**SBI241 -- week 3** **Renal Failure** - *[Acute]* = sudden, sharp decline in renal function, can be reversible - *[Chronic]* = gradual decline in renal function over time = irreversible **Chronic Kidney disease (CKD)** - Irreversible loss of renal function that affects all organ system which can be caused by a variety of different pathophysiological conditions - Can lead to a development as a complication of systemic diseases (Hypertension, Diabetes) or as a complication of many renal diseases (Chronic glomerulonephritis). **Renal diseases** 1. Glomerular Diseases 2. Tubular Diseases 3. UTI 4. UTO -- Urinary Tract Obstruction **Glomerular Diseases** - *[Acute glomerulonephritis]* -- Large, inflamed glomeruli with decreased capillary lumen and rapid onset of haematuria and proteinuria. - *[Chronic glomerulonephritis]* -- Glomerular scarring and eventual loss of functioning nephrons, gradual development of uremia may be first sign. **Glomerulonephritis: Clinical Manifestation** - Hypertension - Renal Failure - Two major changes distinctive of more severe glomerulonephritis are: - [Haematuria] with RBC casts - [Proteinuria] exceeding 3-5g/day with albumin as the major protein. - [Gross proteinuria] = associated with nephrotic syndrome **Tubular diseases** - Result in decreased excretion/reabsorption of certain substances or reduced concentrating capability. - [Renal Tubular acidosis] = Disorder affecting acid-base balance **Urinary tract infection** - Inflammation of the urinary epithelium caused by bacteria from gut flora - Can occur anywhere in the urinary tract. - Common pathogens: - Escherichia colo - Staphylococcus saprophyticus **Pyelonephritis** *[Acute pyelonephritis]* = Acute infection of the renal pelvic most commonly by Escherichia coli and Proteus Mirabilis. Ascends from the lower urinary tract. - Men = prostatitis and prostatic hypertrophy because urethral obstruction predispose to bacterial infection - Can also be caused by blood infection *[Chronic Pyelonephritis]* = Persistent or recurring episodes of acute pyelonephritis that leads to scarring. **Urinary Tract Obstruction** -- can be caused by calculi or tumours - Renal calculi are stones in the urinary tract and the causes of upper urinary tract obstruction. Formed by combination of various crystallized substances - Men are more at risk than women - Symptoms may depend on the location of the renal stone - Silent stones causing obstruction may lead to CKD. *[Certain systemic diseases that can cause CKD. ]* - Diabetes - Hypertension - Lupus CKD = decreases GFR and tubular functions **GFR** - Measurement of GFR is a good indicator of kidney function - Calculate GFR = calculate clearance of a substance by kidneys over a period of time - *[Creatinine]* -- breakdown product of muscle is normally cleared from the blood by the kidney, through the process of filtration. Kidneys not working = level of creatinine in blood increases **eGFR** - Estimated glomerular filtration rate is based = creatinine, age, body, size, gender and race. Common formula in clinical practice: - Cockcroft-Gault equation - Modification of Diet in Renal Disease (MDRD) equation **Evaluation** - CKD is based on risk factors, history and presenting signs and symptoms - Elevated serum creatinine and serum urea concentrations are consistent with CKD - Markers of Kidney damage include urine protein, albumin and examination of urine sediment - Ultrasound, CT and x-rays will show small kidney size - Renal biopsy confirms the diagnosis **Management Principles** The mainstay of management involves: - Dietary control - Fluid evaluation - Sodium, potassium and phosphate restriction - Adequate kilojoule intake - Management of dyslipidaemias - Iron, folic acid and erythropoietin replacement therapy as needed - Angiotensin-converting enzyme (ACE) inhibitors or receptor blockers are often used to provide renal protection and to control systemic hypertension. **Alzheimer's Disease** - Most common type of dementia - The risk of developing Alzheimer increases with age. As it progresses, lack of concentration and disorientation occur. - Inability to retrieve semantic memories occurs early and manifests as difficulty in finding the words to formulate or follow speech, failure to recognise or identify people or objects. **Pathophysiology** - Characterised pathologically by death of pyramidal cells, neuritic plaques, neurofibrillary tangles, particularly in the hippocampus, temporoparietal and front cortices. - The patients exhibits memory loss, poor judgement, disorientation, confusion and changes in personality. Can lead to mood swings and violent outburst. **Dementia** - Set of symptoms that include gradual loss of memory, mood change and problems with communication and reasoning. - Occurs when the brain is damaged by certain diseases like Alzheimer's Disease or a series of small strokes **Encoding the memory** - Short-term memory is stored in the frontal lobe but only temporarily (seconds to minutes) and the info needs to be consolidated into long-term memory because the space is limited. - Long-term memory resides in the hippocampus and last years/lifetime. - PLASTICITY = ability to alter the anatomy and function in response to changes in its activity patterns. New neurons and synapses are produced in the areas involved in memory. - LTP = repeated stimulation results in increased strength of that synaptic connection. **Role of inflammation** - Aggregates and larger deposits of plaques and tangles elicitan inflammatory - This response assists in the clearance of the aggregated peptide but may also stimulate the secretion of mediators that cause damage.