The urinary system consists of the following organs: two
kidneys, two ureters, a urinary bladder and a urethra. The functional
unit of the kidney is the Nephron. The functions of the urinary system
include regulation of the body fluid volume, pH, osmolarity, and
electrolyte composition; excretion of metabolic waste products and
excretion of foreign substances; activation of vitamin D; and
production of the hormones renin and erythropoietin.
An Overview: The average kidney is about 10 cm long, 5.5 cm wide and 3
cm in thickness. The kidneys are located on the posterior wall of the
abdominal cavity and either side of the vertebral column. They are
typically located between the level of the T12 and L3 vertebrae.
The kidneys, the two ureters (which connect the kidneys to the urinary
bladder) are behind the peritoneum or outside the peritoneal cavity.
As a result, these organs are sometimes described as being
retroperitoneal. The bladder is located in the pelvic cavity under the
peritoneum. Each ureter (approximately 30 cm long) descends
lateral to the vertebral column and enters the posterior, inferior
surface of the bladder. The urethra exits the inferior surface of the
bladder and empties to the exterior of the body. In females the
urethra is short, about 4 cm, while in males it is about 19 cm long.
Listen as your read:
The
Nephron: The real work of the urinary system is done by the
nephrons within the kidneys. The 2 ureters and the urethra are little
more than conduits for moving urine; and the bladder is used to
hold urine between periodic urinations (micturitions). Each
kidney contains about 1.25 million nephrons. On average 20% of the
cardiac output goes to the kidneys each minute or about 1 liter of
blood per minute (renal blood flow). From that liter of blood the
nephrons filter and process about 125 ml per minute. If all of
the filtered amount were turned into urine, it would equal
about 180 liters per day. However, the nephrons aggressively
reabsorb most of the filtered water and put it back into the
circulation. Ultimately only about 1.5 liters (less than 1%) of
water is excreted per day. This volume is more than enough to
remove the waste products processed by the kidneys. In general, the
kidneys must excrete a minimum of 500 ml per day to remove the
necessary amounts of waste products. Even at 1.5 liters per day, each
nephron is only processing about 0.0006 ml per day or 0.000000417 ml
per minute. As you can see in the diagram, the nephron is
intimately associated with the vascular system. Plasma is filtered
at a specialized capillary called the glomerulus, while the
reabsorbed water is returned to the circulation via capillaries that
surround the remaining parts of the nephron. As the filtered
fluid passes along the nephron the cells lining the tubules
adjust osmolarity, volume, pH and electrolyte balance. Once the
fluid leaves the collecting duct its composition can no longer be
adjusted. From this point on, it is called urine and is destine
for elimination without any further changes.
Catheterization: The process of
placing a catheter into the bladder to drain urine from the bladder.
Patients who are unconscious or are immobile are catheterized until
they are able to urinate either with or without assistance.
Catheterization is common cause of hospital acquired cystitis. For
paraplegics and quadrapeligics, cystitis from repeated catheterization
is constant problem. Clean catch: Method used to get a urine sample. Urine in the
bladder is normally sterile (without bacteria) however, there is
bacteria in the distal region of the urethra. To avoid contaminating
the urine sample with the bacteria in the distal urethra, urination is
started, to flush the bacteria from the urethra, then the specimen cup
is placed in the urine stream to catch the remainder of urine in the
bladder. Continuous ambulatory peritoneal dialysis (CAPD): A process in
which clean dialysis fluid is introduced into the peritoneal cavity
with a catheter. The dialysis fluid draws waste products from the
blood as the blood passes through the capillaries of the peritoneum.
Later the dialysis fluid containing waste products is drained from the
peritoneal cavity and replaced with fresh fluid. The process allows
the patient to continue with daily activities since they do not have
to been linked by tubing to a dialysis machine. Cystitis: Inflammation of the urinary bladder. Dip stick urine tests: Quick test for urine in which a plastic
strip with various reagents patches is immersed in a urine sample. The
colors changes seen on the reagent patches are compared with a
standard chart to determine if there are changes. Dip sticks can
detect such things as Glucose, Ketones, Protein, pH, Blood/Hemoglobin,
Leucocytes, Urobilin, Specific gravity, Nitrite, Urobilinogen and
Bilirubin. Diuretic: A substance [caffeine, alcohol] or drug [furosemide (Lasix),
that increases urine production. Dysuria: Difficult or painful urination. (dys = difficult or
bad) (ur = urine) Frequency: A symptom of cystitis in which the patient feels
that they must urinate much more frequently than normal. Glucosuria: Presence of glucose in the urine. (gluco = glucose) Gonorrhea: Type of urethritis caused by Neisseria gonorhoeae (a
gram-negative diplococcus). (rrhea = flowing) Hematuria: Presence of blood in the urine. Hemodialysis: The process in which the functions of the kidneys
are replaced by a machine. Blood from the patient is passed through a
machine that filters, cleans and adjusts the blood before being
returned to the patient.
Hyperplasia: An abnormal increase in the number of cells in an
organ or tissue which results in enlargement of the organ or tissue. Incontinence: Inability to retain urine in the bladder. Nocturia: Needing to urinate during the night. Nosocomial: An infection acquired while in the hospital. Proteinuria: Presence of protein in the urine. Pyelogram: An X-ray of the kidney and the ureters. (pyelo =
pelvis) Pyelonephritis: Inflammation of the kidney and renal pelvis. Renal calculi (Kidney stones): Kidney stones are calcium
deposits that precipitated from the urine. Most are small enough to
flow through the system and exit in the urine. However, some can be
large enough that they obstruct the flow of urine. Urethritis: Inflammation of the urethra. Urgency: A symptom of cystitis in which the patient feels a
strong desire to urinate. Urinary obstruction: A situation in which something (calculi,
tumor) blocks the flow of urine through some part of the flow pathway. Urinary tract infection UTI: An infection of the urinary tract
usually caused by a bacteria, and usually of the urethra or urinary
bladder. E. coli is the most common bacteria associated with this
condition. Void: A verb use to describe the process of emptying the
bladder.
Instructions: work with a partner. One
person can read the part of the doctor and the other person can read
the part of the patient.
D: Good afternoon Ms. Jones.
P: Hi Dr. Musaf.
D: What seems to be the problem?
P: I think I may have a bladder infection.
D: Really – tell me what kind of symptoms you’ve been having.
P: For starters I’ve got a crampy feeling in my lower abdomen and I
also have some bad lower back pain.
D: When did the cramps start?
P: About a week ago.
D: And you’re sure they are not related to your period.
P: Yes, I finished my last period about two weeks ago.
D: Are you periods normal – any problems – excessive bleeding, more
cramping than normal or irregular timing?
P: No, they are normal.
D: What is your normal cycle?
P: About 30 days.
D: Okay – go on – what other symptoms do you have?
P: It seems like I have to pee every few minutes – I always have the
sensation that I need to go.
D: That is a common symptom.
P: There is also a slight burning sensation when I urinate and my
urine is cloudy and has a strong smell. I’ve also had a low grade
fever for the past few days.
D: Have you had any recent illnesses – a cold or flu?
P: No – I’ve been very healthy.
D: Well -- all the things you have described certainly fits cystitis.
We can check it out pretty easily. Here is a sample cup – please take
it down to the toilet and bring back a sample. We will need a clean
catch – so start the stream first and then get the sample. We don’t
need much – half the cup is more than enough.
P: Okay – no problem, I already feel the urge to go again.
D: Great.
P: I’m back! Is this enough?
D: Yes that’s fine. Let me test it with one of these urine quick test
strips.
P: Really – it’s that simple?
D: Yes. This little strip can test a variety of things some of which
are very indicative of a bladder infection.
P: Maybe I should get a can of those.
D: You can – they are sold over the counter. Well – let’s see what
we’ve got? Nitrates are positive, leukocytes are positive and a trace
of red blood cells – everything else is normal.
P: Is that good or bad?
D: These findings are consistent with a bladder infection. Nitrites
are byproducts of bacterial metabolism and leukocytes are the cells
you body uses to fight the bacteria.
P: What about the blood?
D: Blood is sometimes present if the infection is moderate to sever. I
want to do one more thing – let’s put a little bit in a tube and spin
it down.
P: What will that do?
D: That will concentrate all this cloudy material in the bottom of the
tube – we can then stain it and take a look at it under the
microscope.
D: I got a TV monitor hooked to the microscope so you can also see
what in there.
P: Great – I think?
D: Okay – well see all those little things swimming about on the
monitor?
P: Yes.
D: Those are bacteria – lots of them.
P: Those are in my bladder?
D: Yes and they seem very happy.
P: #@$#%#$
D: Don’t worry – 90% of bladder infections are caused by E. coli which
is a common bacteria and can be easily treated.
P: Okay.
D: Are you currently taking any medications?
P: No.
D: Are you seeing any other doctors for any health problems?
P: No.
D: Okay – well, I’m going to prescribe you seven days of Macrodantin,
which is an antibiotic and I’m also going to give you 2 days worth of
pyridium, which will relieve some of the more unpleasant symptoms
you’re experiencing.
P: Just 2 days worth?
D: While you will need to take the antibiotic for 7 days, the symptoms
should be gone in 2 days. So I don’t think you will need more than 2
days of Pyridium.
P: Okay.
D: You will need to take the Marcodantin four times a day – and you
should take it after meals. I want you to start it right away – so
grab a bite to eat and get the first one down ASAP. You can then take
one after dinner tonight and then one more with a glass of milk before
bed. Tomorrow you can just divide the four doses evenly throughout the
day.
P: Okay.
D: The Pyridium should be taken 3 times a day and it should also be
taken with food and at least 2 glasses of water. Now Pyridium will
turn your urine red-orange – so don’t be alarmed – this is quite
normal. And Pyridium will stain you underwear – so don’t wear any that
you don’t want stained orange.
P: That’s good to know.
D: As I said, the pain should be gone in 2 days – if the pain persists
after 2 day I want you to call me.
P: Okay.
D: I also want you to increase you water intake – and make sure you
finish all the antibiotics, even if you’re feeling fine. If you don’t,
you run the risk of the infection coming back.
P: Okay.
D: I’m also going to send your sample to the lab for a positive ID of
the bacteria in your urine. It’s not likely, but if it turns out to be
something other than E. coli I may want to change the antibiotic
you’re taking. If that happens I’ll call you and let you know. If you
don’t hear from me, you can assume that everything is fine. But I
expect everything to be okay and after 7 days you should be fully
recovered.
P: Okay.
D: Before you go – can you tell me what sort of work you do?
P: I work in a microprocessor assembly factory. Why? Is that
significant?
D: Do you work in one of those clean rooms and wear those white suits?
P: Yes – but the work is easy – nothing strenuous and my coworkers are
great.
D: I’m not worried about the labor part. How often do you get to go to
the toilet?
P: Oh we can go whenever we want – but we have to go through the
hassle of un-suiting, then going and re-suiting.
D: So I’m guessing you go as seldom as possible.
P: Pretty much.
D: How many times do you urinate each day?
P: I don’t know – may 3 or 4 times.
D: How about at night?
P: Normally never – but since this started – may 3 or 4 times a night.
D: Isn’t it uncomfortable to work while needing to pee?
P: We all have a routine – we rarely drink anything before lunch and
almost nothing at lunch. If you don’t drink – you don’t have to pee.
D: How much water do you drink each day?
P: Not much, 2 cups of coffee, a glass of tea and a soda maybe.
D: Well that is a problem – the dehydration and the infrequent
urination is the perfect recipe for a bladder infection. If you are
going to continue at this job you are going to have to start drinking
and urinating more normally or you’re going to be in here with a
bladder infection every few months. It may be a hassle, but you and
your coworkers need to make some changes. If it would be helpful for
me to explain this to the plant manger I will be glad to talk to them.
P: Thanks – but I don’t think they mind – it’s more about us just not
wanting to go through the hassle. But I guess I’ll have to just get
used to it.
D: The key is to not dehydrate yourself and to urinate when the urge
hits – I mean you can delay for a while, but don’t hold if for an hour
or more.
P: Okay.
D: And try to drink at least a liter and half of water each day.
P: Well do.
D: Here – this brochure that will give you more information about
cystitis and things you can do to avoid future cases.
P: Great thanks.
D: Unless, there is a problem, I don’t think there will be a need for
a follow-up visit.
P: Okay.
D: Great – call me if you have any problems.
P: Okay – thanks Dr. Musaf. Have a good day.
D: You too – bye.
Instructions: Work with a partner and take turns asking the
following questions. When answering, practice giving full answers, not
short cryptic answers – don’t limit you use of language.
What is the patient’s chief complaint?
Based on the interview, what is the minimum and maximum age you
would predict for this patient? What is the rationale for your
conclusion?
Is this patient seeing any other doctors for health issues?
How long has the patient been experiencing the chief complaint?
What symptoms does the patient include as part of the
description of their CC?
What is the initial diagnosis?
Describe the medications included in the treatment plan. What is
the purpose of each?
What urine parameters were particularly important in making the
diagnosis? Why?
Why is the doctor interested in the patient’s monthly cycle?
Why is the doctor concerned about the patient’s work
environment?
Instructions: work with a partner to write
questions that would generate the listed responses from a patient.
Then put the Q and A in what you think is the most logical sequence.
Compare your sequence with other groups.
Questions
Responses
Sequence
I usually go three or four times a day.
I’ve them for about 1 week.
My cycle is about 30 days,
I work in a microchip factory.
Yes, it is very cloudy and has a foul smell.
My health has been fine I haven’t had any recent illnesses.
No, I’ve never had this problem before.
I don’t drink much water, some coffee and tea.
No, I’m not taking any medicines.
No, my periods have been very normal.
Instructions: Use the word pairs to complete the sentences.
One word in each pair should in the past continuous and the other word
in the pair should be in the past simple.
Mini-lesson: A common use for past continuous relative to
the past simple is when we want to describe a process that was taking
place in the past that was interrupted by some event.
Example: I was surfing the internet when my brother called from
Alaska. (In this example “surfing” is the process that was taking
place in the past, which was interrupted when my brother “called.”)
Prostatic hyperplasia should not be confused with prostatitis.
The most common cause of prostatitis is a bacterial infection which
can be treated with antibiotics. Benign prostatic hyperplasia is a
hormone induced increase in the number of cells in the prostate
gland. Because the prostate completely surrounds the urethra, any
increase in the size of the prostate has the potential to compress
the urethra and restrict or completely block the flow of urine
from the bladder. The resulting symptoms include hesitancy,
intermittency, incomplete voiding, weak urinary stream,
and straining. Additionally patients experience frequency,
which when it occurs at night is called nocturia, and urgency.
If left untreated the condition can lead to bladder infections,
urethral infections, bladder stones and urinary retention with
resulting bladder distension.
Benign
prostatic hyperplasia affects middle-aged and elderly men. About
one-half of men over fifty have some degree of hyperplasia and the
percentage increases with age. By age 90, the percentage of men with
this condition may be as high as 90%. The condition is related to the
production of testosterone, although the exact hormonal interactions
that lead to the condition are still being elucidated. What is
clear is that circulating testosterone is converted to
dihydrotestosterone (DHT) by the stromal cells of the prostate gland.
DHT then binds with nuclear androgen receptors which lead to
transcription of mitogenic growth factors that act on the stromal and
near by epithelial cells. The increased mitosis leads the hyperplasia
associated with this condition.
Benign prostatic hyperplasia can be managed with drugs (alpha
blockers) that relax the smooth muscle in the prostate gland and the
smooth muscle associated with the internal urethral sphincter. The
relaxation allows urine to pass more freely through the enlarged
prostate gland. If pharmacological interventions are inadequate
there are a variety of surgical / laser techniques that can be used to
reduced the size of the prostate gland.
Instructions: Work with a partner. Read the
sentences in column A and find the word in column B that best
completes the sentence.
A
B
The patient reported having a _____ during urination.
Diabetics have to _____ their urine for protein, ketones and
glucose each day.
Cystitis can cause abdominal _____.
Some drugs used during anesthesia can cause urinary _____.
Prostatitis is usually _____ with antibiotics.
Benign prostatic hyperplasia is a common problem in _____ men.
Acute urinary retention produces an extremely _____ bladder on
palpation.
With chronic retention the bladder _____ and the distention
caused by retention is usually painless.
The prostate gland is often _____ by palpation through the
anterior wall of the rectum.
The urogenital diaphragm forms the external urethral _____.
While females do not have a prostate gland they do have an _____
called the Skene’s gland, and like the prostate it can sometimes
become inflamed due to a bacterial infection.
Prostatic specific antigen (PSA) is an _____ of a prostatic
malignancy.
Women tend to have more urinary tract infections (UTIs) than men
because of the _____ between the urethral opening and the anus and
because of shorter urethral length.
Patients who receive kidney transplants require life-long _____
to prevent rejection of the transplanted kidney.
Statistics indicate that a kidney transplant can _____ a
patient’s life by 10 or 15 years relative to dialysis.
Normal urine is usually described as being _____ in color.
Bacterial infections can produce _____ , murky or turbid urine.
Dark brown urine can indicate liver _____ .
Certain vegetables, such as asparagus, can cause the urine to
have a strong _____ .
_____ can cause the urine to be darker yellow than normal.
Listening Activity: Listen to the YouTube video on
Renal Anatomy and Physiology
(the video may take a moment to load and is about 5 minutes long).
This is a nice listening review of technical and nontechnical terms.
Useful Vocabulary
Listen for these expressions. Many of the terms are used to transition
from talking about one topic or area to another.
The
Nephron: The real work of the urinary system is done by the
nephrons within the kidneys. The 2 ureters and the urethra are little
more than conduits for moving urine; and the bladder is used to
hold urine between periodic urinations (micturitions). Each
kidney contains about 1.25 million nephrons. On average 20% of the
cardiac output goes to the kidneys each minute or about 1 liter of
blood per minute (renal blood flow). From that liter of blood the
nephrons filter and process about 125 ml per minute. If all of
the filtered amount were turned into urine, it would equal
about 180 liters per day. However, the nephrons aggressively
reabsorb most of the filtered water and put it back into the
circulation. Ultimately only about 1.5 liters (less than 1%) of
water is excreted per day. This volume is more than enough to
remove the waste products processed by the kidneys. In general, the
kidneys must excrete a minimum of 500 ml per day to remove the
necessary amounts of waste products. Even at 1.5 liters per day, each
nephron is only processing about 0.0006 ml per day or 0.000000417 ml
per minute. As you can see in the diagram, the nephron is
intimately associated with the vascular system. Plasma is filtered
at a specialized capillary called the glomerulus, while the
reabsorbed water is returned to the circulation via capillaries that
surround the remaining parts of the nephron. As the filtered
fluid passes along the nephron the cells lining the tubules
adjust osmolarity, volume, pH and electrolyte balance. Once the
fluid leaves the collecting duct its composition can no longer be
adjusted. From this point on, it is called urine and is destine
for elimination without any further changes.
Benign
prostatic hyperplasia affects middle-aged and elderly men. About
one-half of men over fifty have some degree of hyperplasia and the
percentage increases with age. By age 90, the percentage of men with
this condition may be as high as 90%. The condition is related to the
production of testosterone, although the exact hormonal interactions
that lead to the condition are still being elucidated. What is
clear is that circulating testosterone is converted to
dihydrotestosterone (DHT) by the stromal cells of the prostate gland.
DHT then binds with nuclear androgen receptors which lead to
transcription of mitogenic growth factors that act on the stromal and
near by epithelial cells. The increased mitosis leads the hyperplasia
associated with this condition.
