An elderly female patient has a history of osteoporosis, chronic type II diabetes mellitus, and high blood pressure. She has come to the doctor today because she has noticed blood in her urine. Her doctor is now primarily concerned about the effect of high blood pressure on her kidneys and the effect of low kidney function on her already compromised bone mass. What could be going on that explains all of this? How are blood pressure, kidney function, and bone mass related?


Background Information

Upstream Causes

Downstream Effects

Urinary System Anatomy

Urinary System Physiology

Nephrons

General Information on:

DM II

Osteoporosis

Hypertension

Relation to kidney function and other important symptoms/factors

Effects of her different conditions

Kidneys (2)

Ureter (2)

Aorta

Bladder

Inferior Vena Cava

Urethra

Carries the deoxygenated blood from the kidney's and lower half of the body back up to the heart to be reoxygenated

Carries oxygenated blood down to the kidney's and lower half of the body to be filtered and used in the cells

Fist sized, bean shaped organs that filter bodily fluids

Lie on either side of the spine, close to the back

Consist of 3 layers (superficial to deep)

Renal Medulla

Renal Pelvis

Renal Cortex

Specialized cells called NEPHRONS

Ducts that push urine through peristalsis from the kidneys to the bladder

Hollow muscular organ (much like the stomach) that collects and stores urine for disposal

Is flexible, and can hold as much as 1 L of urine, 500 mL comfortably

The duct leading from the bladder out of the body, expelling urine

image

Microscopic functional unit of the kidney that regulates water and soluble substances by filtration, reabsorption and excretion

Structure

Proximal tube (PCT)

Loop of Henle

Distal tubule (DCT)

Collecting duct

Glomerular Capsule

Glomerulus

"Ball of yarn" that releases ions and other particles to be taken into the nephron and filtered

Surrounds the glomerulus and takes up the filtrate to be processed by the nephron

Located solely in the renal cortex of the kidney

Selective re-absorption of glucose, water and other nutrients

Cells of PCT are ciliated and filled with mitochondria for lots of reabsorption(much like the small intestine)

Creates filtrate

Filtrate

Substance that has passed through a filter

Contains

H20

Salts

HCO3

H+

Urea

Glucose

Amino Acids

Sometimes drugs

Secreted Out

Absorbed in

NaCl

H20

HCO3

Nutrients

K+

H+

NH3

AKA Nephron Loop

Descending Limb

Think ascending segment

Thick ascending segment

Part of the nephron that forms a long loop through the outer and inner medulla of the kidney, where water and salt are primarily reabsorbed into the blood

Connects to the PCT and Thin ascending segment

H2O is secreted out here in the outer medulla

Where the loop turns in the inner medulla and begins to return to the outer medulla

Secretes NaCl

The end of the loop that connects to the distal tubule in the cortex

NaCl is also secreted here as well

Similar to the PCT, leads to the collecting duct

Located solely in the renal cortex

Reabsorbs

Secretes

K+

H+

Calcium

Sodium

Chloride

NaCl

H2O

HCO3

Regulates the pH of urine

Located at the end of the nepron tube chain, in the inner medulla

Aquaporins

ADH (anti-diuretic hormone) triggers the movement of aquaporins to the side of the cell they aren't on here, allowing reabsorption and secretion to take place

Special protein channels in the cell membranes that help transport water in and out of the cell

Help in the collecting duct so more water can leave the urine

Alcohol and caffeine inhibit ADH it means less water is released when they are consumed

Secretes

NaCl

Urea

H2O

Also located in the descending part of the loop of henle

image

Kidneys

Ureters

Bladder

Urethra

Remove waste products and drugs from the body by filtering them through specialized neprhon cells

Balance bodily fluids

Release hormones to regulate blood pressure

Help control the production of red blood cells

Urea with water and other solutes forms urine and is passed through nephrons down the renal tubes of the kidneys

Two narrow tubes connected to either of the kidneys that move urine via peristalsis down to the bladder

Walls that relax and expand to release and store urine

Send neural signals to brain to signal when it's time to urinate

Pontine storage area

Pontine micturition center

Red light

Green light

Sphincter muscles

Keep urine from leaking out by closing tightly around the bladder opening

Final tube at the end of the urinary system that allows for urine to be excreted from the body

Neural signals tell the bladder and sphincter muscles to relax which allows for urination

Trigone

Lateral walls

Dome

Posterior walls

Triangle shaped area where the urethra meets the bladder

right and left walls on either side of the trigone

Back wall

Roof of the bladder

Abnormally high blood pressure (when the pressure against the arterial walls is too high)

Generally classified as anything 140/90 or higher

Often has no symptoms, but if left untreated can lead to heart attack or stroke

Can be maintained with a low sodium diet, exercise and medication

Type 2 Diabetes

A chronic condition that affects the way the body process' blood sugar

The body doesn't produce enough insulin, but is generally characterized as a bodily resistance to insulin

Not innate, or genetically inherited, but can occur overtime generally due to a high sugar diet

A condition where the bones become weak and brittle

New bone creation doesn't keep up with bone removal, bone remodeling moves faster than creation

Density and quality of bone are reduced

As bones become more fragile, the risk of fracture is greatly increased

Often no symptoms until the first bone break occurs

Indirect Causes

Direct Causes

Osteoporosis

Hypertension

DM II

Effects of her disorders on Kidneys

Further Effects of the medical problems

How do the conditions affect each other

Blood in urine?

If left untreated?

Can lead to urinary tract infections

Since the glucose isn't being properly absorbed into her body due to insulin resistance, her kidney's will simply filter it out

Can impact blood flow, nerves and sensory function in the body, messing with the Kidney's ability to filter blood

Overtime, damage to kidney's and waste buildup in the blood

Diabetic Kidney Disease (very common in people with diabetes, high risk)

Chronic Kidney Disease (CKD)

Many of the medications that are out there to treat osteoporosis have a significant effect on renal function

Can cause kidney stones (your body passes more calcium due to your bones breaking down faster than they can grow)

Second leading cause of kidney failure

Over time it can cause the arteries surrounding the kidneys to narrow, weaken or harden

Could also be a symptom of kidney disease to begin with

Kidney's help in controlling blood pressure by removing waste products and excess water

THE BLOOD IN HER URINE

Her age

Her diet needs to be considered

The medication she may be taking for her amalgamation of conditions

The amount of physical activity she does

The conditions each have a significant impact on the kidneys

2/3 cause some form of kidney disease

Hypertension can cause the kidney's to weaken or grow hard which hinders their function

The same hindrance of function listed in the upstream causes

DM II causes an excess of glucose to exit the body, which leads to an increase of filtrate in her kidney's which could lead to a ride in blood pressure

Hypertension can lead to an increase in calcium secretion which can lead to an acceleration in osteoporosis

Hypertension can lead to an increase in risk for DM II and is present in over 50% of patients with diabetes

Diabetes increases osteoclast function but decreases osteoblast function which leads to accelerated bone loss and ultimately osteoporosis

Could be caused by Kidney Stones from excessive breaking down or improper removal of minerals

Kidney Infection (or UTI)

Kidney Disease

Kidney disease (which could also be causing the hypertension)

The Diabetes seems most likely to be the underlying/root cause for many of her other issues

Diabetes is oftentimes linked with Diabetic Kidney Disease which can lead to a rise in hypertension and blood in the urine

The osteoporosis most likely stems from her age and the affected osteoclasts/blasts from the diabetes

Each of her issues can be treated with it's own independent medicines, which can have an array of side effects

Medication is processed in the kidney's, so an abundance could cause damage

Blood in the urine is a symptom of something underlying

Ultimately, with her kidney's at such high risk from her other ailments, her kidney's will eventually shut down

No kidney's = no waste processing

No waste processing = buildup of waste/toxins in the blood

Medication, proper diet, and mild exercise so she doesn't hurt herself would aid in reducing her symptoms

Improving her water intake might also aid in her problems as well, as Diabetes can leave you dehydrated in the first place