First of all, let me start by saying that if anyone has any notes they’d like to add- please send me a message.
Kidneys are surrounded by a fat layer with the adrenal gland settled on top of the organ. They are enclosed within a renal capsule, with the waste being removed through the ureter. The main organ has two sections, the outer cortex, and the inner medulla. The medulla is made of pyramid structures that contain the loops of henle and lower part of the collecting ducts. The blood flow goes from the renal artery to the kidney and out through the renal vein.
the nephron is the basic unit of the kidney and it is made of capillary loops, bowmans space and podocytes. All of this is within a glomerulus- which is used for filtration. For any substance to go through, it has to travel through the glycocalyx, then the capillary endothelium, the glomerular base membrane and then the podocytes (with their filtration slips and diaphragm). This allows for the reabsorption of water, amino acids, glucose, potassium and 75% of sodium; as well as the secretion of hydrogen, ammonium ions, drugs, creatinine and urea.
The function of the kidney is to excrete waste products of metabolism (such as urea and creatinine), as well as the regulation and maintance of the extracellular fluid. The adrenal gland is important for hormone synthesis.
ASSESSING RENAL FUNCTIONS
The Kidney function usually decreases with age and the dysfunction is usually asymptomatic. This is especially harmful as delayed treatment can cause further abnormalities and can affect the whole body.
When checking the kidney function, the Glomerular Filtration Rate (GFR) is always checked. This shows the volume of fluid from all glomerular capillaries into their Bowman’s capsules per unit of time.
The GFR Renal Clearance is the volume of plasma from which a given substance is completely cleared by glomerular filtration per unit time. For this, checking INULIN is a gold standard- though others such as radioisotope filtration markers, radiographic contrast agents and serum creatinine are also used. If thyroid problems are suspected, serum cystatin is checked.
URALYSIS- Kidney problems identified through urine.
PROTEINURIA- too much proteins in urine
HAEMATURIA- blood present in the urine
GLYCOSURIA- glucose present in the urine
Acute Kidney Injury (AKI)
AKI is a reversible failure of kidney function. To diagnose, a clinical history has to first be checked to assess for any factors which may be causing it and that can be corrected. Afterwards, blood chemistry is used to check for urea and creatinine in serum, for severe acidosis, hyperkalaemia and urine.
For management, first occurs the correction of the AKI causes that can be identified. Them biochemical monitoring occurs and a possible renal replacement therapy (dialysis or hemofiltration)
Chronic Kidney Injury (CKI)
CKI is a progressive and irreversible impairment of the kidneys. Various factors can differ depending on the patients status.
Anaemia means low erythropoietin
Dehydration means poor water absorption
Itchy skin means calcium phosphate in tissues
Hypertension means sodium retention
For management, dietary restrictions are applied, diuretics, vitamin D and erythropoietin.
The renal replacement is the end stage of renal disease. The transplantation is the optimal treatment and can either be done through dialysis or hemofiltration.
Dialysis- is using a semi-permeable membrane to separate blood from suitable fluid via which ions and small molecules move by osmosis
Hemofiltration- also uses a semi-permeable membrane, but the blood is forced through it at high hydrostatic pressure, carrying dissolved electrolytes etc.
erythropoietin- prompts the body to make red blood cells.
renin- produced by kidneys to control the blood pressure.
