Abdomen Urinary System

At 3 weeks gestation the kidneys begin to form columns of mesoderm. By the 5th week of development, three kidneys have developed. These are:

Pronephros

Mesonephros

Metanephros

The Pronephros AKA Forekidney leaves behind a _____ to form the next kidney and has _____ function

duct; no

The mesonephros AKA midkidney provides _______ function while the kidney develops.

partial

Mesonephric duct referred to as the ____________ in males gives rise to the:

Wolffian duct;

epididymis, ductus deferens and ejaculatory duct

Mesonephric duct referred to as the ____________ in females gives rise to the:

Mullerian duct;

uterus, fallopian tubes, proximal vagina 

The permanent kidney AKA Metanephros. Within the ____ week of gestation the nephron function begins

8th

What is the function of the two kidneys?

to produce and secrete urine

What are the 2 ureters used for?

They are tubes leading from the kidneys to the urinary bladder

What makes up the upper urinary system?

Two kidneys & two ureters

What makes up the lower bladder?

One urinary bladder and one urethra

True or false: the kidneys are peritoneal

False; they are retroperitoneal

Which kidney sits higher: right or left?

left (makes it harder to see because of gas and rib shadowing)

Right and left kidney measurements should not be more than ____cm of each other in length

1-2

What is the length measurement of a kidney?

9-12cm

What is the (AP) measurement of a kidney?

4-5cm

How thick is the kidney?

2-3cm

Convex lateral borders of the kidney are found on the outside and concave medial borders are found on the _________

inside

The outer & inner portions of the parenchyma are called and they are responsible for?

Cortex - responsible for filtration

Medulla - responsible for absorption

Review this image

What is the functional unit of the kidney?

The nephron

Where is the nephron located within the kidney?

almost entirely in the cortex

Where are juxtamedullary nephrons located?

Within the medulla

Another term for a network of capillaries within the corpusle? It is surrounded by:

Glomerulus; Bowmans capsule

Blood is brought into the ______________ via the ___________ arteriole where it is non selectively filtered:

glomerulus; afferent arteriole

Blood exits the glomerulus into Bowman’s capsule via:

the efferent arteriole

The filtered substance that was removed from the blood in the glomerulus is refered to as:

filtrate

At what point is the filtrate considered urine?

Once it enters the collecting duct

True or false: each nephron has its own collecting duct

False; several nephrons will drain into a single collecting duct

What does urine drain through?

Papilla

Write out the correct order of production and pathway of urine

Afferent arteriole →  glomerulus →  efferent arteriole →  Bowmans capsule → proximal convoluted tubule →   deceasing loop of henle →  loop of henle →  ascending loop of henle →  distal convoluted tubule →  collecting duct →  minor papilla →  minor calyx →  major calyx →  renal pelvis →  ureter →  bladder →  urethra

Unfiltered blood enters the corpuscle via the ______________

affarent arteriole

Blood is non selectively filtered in the ___________

glomerulus

Filtered blood exits through the corpuscle via the ______________

efferent (exit) arteriole

Filtrate enters the tubule through an opening in:

Bowman’s capsule

Reabsorbtion occurs along the different sections of the tubule via 

Pertubular capillaries & venules

Urine drains from the distal convoluted tubule into a:

collecting duct

After the collecting duct how does urine get to the urethra?

papilla → minor calyx → major calyx → renal pelvis → ureter → bladder → urethra

Renal arteries are ____________ branches of the abdominal aorta just below the SMA

lateral

Which is longer the right renal artery or the left and where is it traveling?

The right is longer and it travels posterior to the IVC

This is right coronal view of the proximal renal arteries. Identify if the right or left arteries are on the orange or blue.

Orange: left

blue: right (posterior to the IVC)

keep in mind the right renal artery is positioned at 10:00 and the left is at 4:00

The right renal vein is ____________- than the left renal vein

shorter

What is this picture showing?

The right renal vein draining into the IVC

What is the order of blood flow through the kidney?

Renal artery → segmental arteries → interlobar arteries → arcuate arteries → interlobular arteries → arrerent arterioles → glomerular capillaries → efferent arterioles → peritubular capillaries → vasa recta → interlobular veins → arcuate veins → interlobar veins → renal vein            

Ureters undergo ______________ in order to facillitate the flow of urine from the renal pelvis towards the bladder

peristalsis

Can we see normal ureters on ultrasound?

Not well

Is the urinary bladder a retroperitoneal organ?

yes

The bladder wall consists of four layers. List from superficial to deep

Serosa → muscular → submucosa → mucosa

What makes up the trigone of the bladder?

two posterior ureters & one inferior urethra

The _________ muscle controls the UB contractions

detrusor muscle

Which wall of the bladder do we measure?

anterior wall of a full bladder

What is being measured here?

the anterior wall of the bladder

Which sphincter of the urethra is voluntary and involuntary?

Internal sphincter - involuntary sphincter

External Sphincter - voluntary control

What is the main function of the kidneys?

filter wastes from the blood and produce and excrete urine

Urine is primarily made up of _________

96% water

What helps control the following:

Blood pressure

Ions

pH

Osmolarity (protein balance going back and fourth)

The Kidney

When BP is elevated, the kidneys help lower it by:

excreting excess salt and water

When blood pressure is too low how do the kidneys help make it rise?

They reduce the amount of salt and water removed from the blood and the enzyme renin aids in constriction of blood vessels causing BP to rise

When ion levels are too high, the kidneys will:

increase their levels of excretion

When ion levels are low, the kidneys will:

allow ion reabsorption into the blood

Kidneys monitor and regulate levels of _____________ and ____________ in the blood to control PH

hydrogen ions (H+) and bicarbonate ions)

Laboratory data: kidney function can be evaluated by testing:

Blood & Urine

A patient with a urinary tract infection (UTI) may present with an increase in

WBC

In addition to being able to detect a UTI urinalysis also tests for specific gravity which is:

the kidneys ability to concentrate urine. Meaning if you drink more fluid specific gravity will decrease and vice versa

Increased levels of BUN (Blood Urea Nitrogen), Creatinine and Uric acid all indicate:

renal function impairment

The three steps involved in the production of urine:

1) glomeruluar filtration

2) tubular reabsorbtion

3) tubular secretion

What enzyme is released by the kidneys to help lower BP?

Renin

Which type of kidney image is this?

longtudinal 

What section of the kidney is this and which scan plane?

Transverse midpole (has a horseshoe shape)

What portion of the kidney is this that looks like a donut

upper & lower poles in transverse

What does CB stand for in this image?

Column of Bertin

What is this image showing?

More of the liver is shown in this image so it is the ________ kidney

Right kidney is shown

Prominent Columns of Bertin can be mistaken for:

a renal mass 

Congenital variants: Compensatory hypertrophy

enlargement of the healthy or unaffected kidney

Found in cases of unilateral renal agenesis or compromised renal function of one kidney

Compensatory Hypertrophy

What anatomic variant is this and which kidney is it most commonly found in:

Dromedary hump: Most commonly found in the left kidney 

What is this image showing:

Dromendary hump

What is the arrow pointing to? A small hyperechoic triangle

Junctional Parenchymal defect

What is the arrow pointing to:

Junctional Parenchymal defect

This type of congenital variant occurs when there is fusion of the kidneys.typically the fusion is of the lower poles

Horseshoe kidney

Which type of analomy is shown in this image→ ?

Horseshoe kidney

When the renal pelvis is located outside the renal hilum what congenetal varient is that?

Extrarenal pelvis

Duplicated collecting system has two subcategories:

complete duplication

incomplete duplication: more common

Complete duplication consists of:

two collecting systems and two ureters

Incomplete duplication consists of:

consists of two collecting systems and two ureters. The ureters will join and only one will drain into the urinary bladder

Which congenital varient is this showing?

The renal sinus is two echogenic regions seperated by tissue. it is a duplicated collecting system

How can we differentiate between an incomplete and complete duplicating system?

Turn on color doppler and if two jets enter the bladder on the same side it is a complete duplication

Congenital varients: Supernumery Kidney is a third kidney that will appear __________. This is very rare

smaller

Congenital variants: 

absence of a kidney

True or false: you need to have at least one kidney to live

true; Bilateral renal agenesis is incompatable with life

When looking for an ectopic kidney you shouldn’t automatically assume one kidney is missing you instead should: 

check the pelvic region first to see if the kidney is there since this is the most common location for ectopic kidney

You can rule an ectopic kidney if:

1) demonstrates an empty renal fossa

2) a single pelvic kidney was found in left lower quadrant

Ectopic Kidney: intrathoracic

results when the kidney continues to ascend. Diaphragm closes below the kidney 

both kidneys are located on one side of the body. What type of ectopic kidney is this:

Ectopic kidney: cross fused

What are the arrows pointing to?

The pyramids of the kidney

What anatomical variant is shown below? 

duplicated collecting system

Is this the right or left kidney? trans or long? upper, mid or lower pole

Right (the C is the correct direction), trans, mid pole

Majority of the nephron is found in:

the cortex