Elderly Female, hx: Osteoporosis, DM II, Hypertension. Complaint: blood in urine
Dx: Potential Kidney Failure
Background
Downstream
Upstream
The Urinary System is comprised of 2 kidneys, 2 Ureters, 1 Urinary Bladder and 1 Urethra. The general purpose is to filter blood to maintain levels of ions, such as Potassium and Sodium Chloride, to maintain water balance and rid the body of excess waste such as urea and creatinine.
Ureters are long, epithelial-lined, fibromuscular tubes that attach the kidneys to the Urinary Bladder. They are Retroperitoneal and the walls are comprised of 3 layers.
The Urinary Bladder is a stretchable, muscular container that stores urine until the body is ready to void. It is located immediately posterior to the pubic symphysis and in females anterior to the vagina, anterior to the rectum and superior to the prostate gland in males. It is retroperitoneal and shaped like and upside down pyramid when empty and an oval shape when full.
There are 2 Kidneys that are located along the posterior abdominal wall and retroperitoneal. They are only partially protected on the posterior side by the floating ribs. They have 4 concentric tissue layers that surround and support them: Fibrous capsule is the Innermost layer of dense irregular connective tissue that keeps pathogens out, Perinephric fat is the second and is adipose connective tissue that supports and cushions, the Renal fascia is third and is dense irregular that anchors to surround structures, and last is the Paranephric fat is adipose and supports and cushions the kidneys. Kidneys are two main functional regions: Medulla and the Cortex
The Urethra is Epithelial-lined fibromuscular tube that connects the urinary bladder to the outside via the External urethral Orifice. The lining of the lumen produces mucin and has smooth muscle that surrounds the mucosa to help push urine out. The male and female urethras are quite different but both contain two sphincters.
The Renal Cortex is the outer section is lighter pink and is identified by the Renal Columns
The Renal Medulla is darker and divided into pyramids by the renal columns.
The Corticomedullary Junction is where the base of the pyramid meets the Cortex
Renal Papilla are the tips of the pyramid that point towards the Hilum and connects to the minor Calyx
Renal Columns are extensions of the cortex that poke into the renal medulla subdividing the medulla into striated Renal Pyramids.
Renal Pyramids are striated and look like rounded triangles
A Renal Lobe is a renal pyramid and part of the Cortex extending from its base. There are about 8-15 per Kidney
The Renal Sinus is medially located in the kidney and is where Urine is "funneled" to be eliminated. The sinus is constructed of progressively larger structures forming the drainage path.
Major Calyces are the points at which the Minor Calyces join leading towards the Renal Pelvis
The Renal Pelvis is a major urine drainage structure that connects to the Ureter.
Minor Calyces get urine from each Renal Papilla
Renal Arteries, Renal Veins, Lymph Vessels, Nerves and some fat are also found in the Renal Sinus
The Nephron is the Functional unit of the Kidney that does all of the filtration and consists of 2 structures: Renal Corpuscle and the Renal Tubule.
The Renal Corpuscle is found in the Cortex and is the part that resembles the ball of yarn. It is primarily made of 2 structures: Glomerulus and Glomerular Capsule.
The Renal Tubule the rest of the Nephron that is not the Renal Corpuscle, it contains 3 continuous parts or tubes.
Glomerulus is a tangle of capillaries that the blood enter via the Afferent arteriole and leaves via the Efferent Arteriole.
The Glomerular Capsule also known as Bowman's Capsule has two layer and resembles a fist shoved into an inflated balloon. It also has two opposite ends that allow the flow of filtrate.
The Parietal layer is impermeable and made of simple squamous epithelium.
The Vascular "Pole" end is where afferent and efferent vessels attach to the Glomerulus.
Visceral layer is permeable and dirctly covers the capillaries of the Glomerulus.
The Tubular Pole is where the renal tubule begins.
The blood passes through 2 different arteriole beds that are sites for filtration, reabsorption secretion.
The Nephron Loop or Loop of Henle is the part of the tubule that "dips" into the medullary region and has 2 segments.
Distal Convoluted Tubule (DCT) begins where the Loop of Henle ends and extends to the collecting tubule. This is also lined with cuboidal epithelium but with fewer microvilli
The Proximal Convoluted Tubule (PCT) is the first region that extends off from the tubular pole of the Bowman's Capsule. This portion is composed of simple cuboidal epithelium that have microvilli for absorption.
Descending Limb has a thick and thin portion, leads from the PCT to the bottom of the loop.
Ascending Limb leads from the bottom of the loop to the Distal Convoluted Tubule. Also has a thick and thin portion.
There are 2 types of nephrons that are distinguished by placement and length: Cortical and Juxtamedullary
Cortical Nephrons are roughly 85% of nephrons with the Bowman's Capsule being near the outer part of the Cortex. The Nephron loop is short and barely dips into the medulla.
Juxtamedullary Nephrons are about 15% or the rest of the nephrons present. They lie along the Corticomedullary Junction in the Cortex, have long nephrons that poke deep into the medulla and Establish a salt concentration gradient, allowing urine concentration to be regulated by ADH
Muscularis is the middle layer, the inner is longitudinal and the outer is circular smooth muscles. Presence of urine in the renal pelvis stimulates these muscles to contract and send urine down to the Urinary Bladder
Adventitia is the External layer made of an array of collagen and elastic fibers within areolar connective tissue. This layer also helps anchor the ureter to the posterior abdominal wall.
Mucosa is the Innermost layer with transitional epithelium. It is stretchy and impermeable to urine so it can't leak out. Lamina Propria is external to the transitional epithelium and if part of the ureter is empty the Mucosa folds into the Lumen or center.
The Urinary Bladder has a region known as the Trigone which is on the posterior wall formed by the connecting ureters. This region doesn't move when bladder fills and acts as a funnel to ensure urine runs down towards the Urethra with the bladder contracts.
The Bladder also has 4 layers that make up the wall.
Mucosa is the innermost with transitional epithelium to handle the shape changes in stretching, is highly vascular, with mucosal folds or Rugae to allow for more stretch
The Submucosa is dense irregular tissue that supports the bladder wall
Muscularis is 3 layers of smooth muscle collectively referred to as the detrusor muscle. The involuntary urethral sphincter is formed from the smooth muscle that encircles the urethral opening.
Adventitia is the Outermost layer of areolar connective tissue that covers the Urinary Bladder. Peritoneum plus the adventitia forms a serosa on the superior surface.
Internal Urethral Sphincter is involuntary and superior to the other sphincters. Surrounds the neck of the bladder and controlled by the autonomic nervous system.
The differences between the male and female Urethras lie in the fact that one is segmented and is used for more than one body system while the other does not.
External Urethral Sphincter is inferior to the internal and made of skeletal muscle fibers therefore making it voluntary.
Female Urethra only functions to take urine to outside the body with the External Urethral Sphincter located near the External Urethral Orifice in the female peritoneum
The Male Urethra has Urinary and Reproductive functions: to carry urine out and semen out. These cannot happen at the same time. It is also segmented into 3 segments.
Membranous is the shortest section and contains the External Urethral Sphincter
The Spongy or Penile Urethra is the longest part and extends to the external urethral orifice.
Prostatic is the part that travels through the prostate gland.
The first bed begins with the Afferent arterioles, enters the Glomerulus, some plasma and other substances are filtered out. the remaining blood leaves the Glomerulus via the Efferent arteriole.
The Efferent arterioles enter the other capillary bed of peritubular capillaries in cortical nephrons or Vasa Recta in Juxtamedullary nephrons.
Peritubular Capillaries intertwine around the proximal and distal Convoluted tubules in the renal cortex.
Vasa Recta are straight vessels that run along the side the Loop of Henle and in the Renal Medulla.
Filtration occurs here because of the differences between the capsular space and glomerular capillaries push out some water and dissolved solutes from the blood as it passes through the capillaries, the fluid that ends up in the capsule is known as filtrate. These freely filtered substances are usually but not restricted to: Water, Glucose, Amino Acids, Ions, some hormones, Vitamins B and C and Ketones
Reabsorption is when some substances that have been filtered out end up in the tubular fluid and your body still needs like glucose, amino acids, ions. Diffusion, Osmosis, or Active Transport moves these substances out of the renal tubules, collecting tubules and collecting ducts back into the bloodstream via the Peritubular or Vasa Recta Capillaries. Most water and solutes are absorbed here.
Secretion is when Solutes that are moving by active transport out of the blood in the peritubular and vasa recta capillaries and back into the renal tubules, collecting tubules, or collecting ducts. These materials or chemicals are moved back to the tubular fluid to be voided from the body.
Substances that are regulated by reabsorption include: Sodium, Water, Potassium, Bicarbonate, Calcium. Sodium reabsorption is regulated by two hormones: Aldosterone that stimulates synthesis of sodium/potassium pumps that become embedded in the membrane and allow more sodium to be reabsorbed. Atrial Natriuretic Peptide (ANP) inhibits reabsorption of Sodium in the convoluted tubule and collecting tubules.
There are 3 types of Nitrogenous waste that can be secreted for voiding: Urea that is produced from the breakdown of protein in the liver, Uric Acid produced from the breakdown of Nucleic Acids in the liver, and Creatinine produced from the breakdown of creatine in the muscles. Other wastes could be Drugs like pain killers, or other chemicals like the ones in our food such as artificial sweetener.
Prior Diagnosese
Diabetes Mellitus II is the adult onset of Diabetes typically brought on by being overweight with poor eating and exercise habits. With this disease the body begins resisting its self made insulin and blood glucose becomes out of control. This disease can be treated and with a strict diet a patient can live a relatively normal life or even become less artificially insulin dependent.
Hypertension is abnormally High Blood pressure and can become Chronic if not able to maintain with diet and exercise. This disease often exponentially increases and leads to heart and other body system failures when not treated early and maintained properly.
Osteoporosis or Porous Bone is just that. Bone that has become weakened and not regenerated thus making it increasingly more porous and brittle. More likely for broken bones that don't heal well.
Diabetes Mellitus II weakens peripheral and smaller blood vessels because of the high blood sugar that can occur. If not treated properly loss of vision, poor circulation in limbs and organs and even stroke can occur.
Hypertension thickens blood vessels and makes them brittle. In smaller vessels they are more likely to collapse or burst.
The Vessels in the Kidneys namely the capillaries are under a higher Hydrostatic Pressure than the rest of the body(60mm hg). If systemic blood pressure rises and persists these vessels will begin to burst or collapse thus reducing Kidney function.
Osteoporosis can increase likelihood of Ca+ deposits in the Kidneys called Kidney stones because of the treatment medications, that in conjunction with a poor diet increases these chances and the chances of damaging the Kidneys.
All 3 of these diseases more or less perpetuate each other and the decrease Kidney activity leading to kidney failure.
Blood in the urine can be a key sign of the Kidneys beginning to fail
When blood sugar is not able to be stabilized by insulin the sugar damages the smaller and more peripheral vessels such as in the eye, kidneys, fingers and feet. The vessels become weak and deteriorate even when sugar is being dumped in the Urine to be voided.
When the blood calcium rises because the Parathyroid Hormone is not relenting the calcium builds up in the small vessels in the Kidneys causing Kidney Stones. These stones can block, damage and even cause rupture in the different vessels and tubes in the Urinary System.
Reduced Kidney function can cause a build of nitrogenous waste as well as excess water and ions being retained putting more stress on already stressed vessels and structures.
With damage in the Urinary tubules it is more likely the patient can contract infections because of the damage and even need a surgical procedure to pass them.
With weakened or collapsed small vessels the body will not be able to absorb and rid itself of excess fluid and edema is likely to occur especially in the feet and legs.
If an infection is contracted the already compromised patient would need to be admitted for close monitoring and IV medications.
All 3 of the Conditions perpetuate weakened and damaged blood vessels in the Kidneys causing excess fluid and wastes to build up in her body due to decreased kidney function.
Kidney disease is shown in a few different tests such as urinalysis when RBC are present as well as in blood labs. Creatinine, Urea and Other nitorgenous wastes would be well outside of the homeostatic limits.
This patient would likely need to be put on Dialysis to assist her body in voiding the wastes and excess water.
This patient is not likely to be able to be on dialysis long with all of her other conditions, she will continue to need more and more care until she is no longer able to be mobile or care for her self at all.