Sessions 8-9-10-11 quiz Flashcards
(41 cards)
What is the most common symptom of UTI in men?
Dysuria (pain on urinating). The next most common symptoms are urinary frequency and urgency.
How can prednisone predispose to UTI?
Prednisone is a glucocorticoid (immunosuppressive drug) used to control inflammatory conditions. The immunosuppression reduces the patient’s immunity against invading/ opportunistic pathogens.
How does the treatment of uncomplicated first time UTI diifer in men vs women?
Both given a course of antibiotics; either trimethoprim or nitrofurantoin. Men have a longer, 7 day course whilst women for 3 days. Nitrfurantoin cannot be given to men where the prostate is involved in the infection because the drug won’t reach therapeutic levels in the prostate. Instead it could drive development of resistant bacterial strains.
Which bacteria is the most common cause of UTI’s in women? Describe its shape and reaction to gram staining.
E.Coli. Normal gut commensal, due to the short urethra of females, it is often displaced from the gastrointestinal tract and can enter urethra. E.Coli is a bacillus and gram negative so will stain red due to a thinner peptidoglycan wall that doesn’t retain the purple dye.
If a woman seeks treatment for the second uncomplicated UTI within 3 months, how does the prescribed antibiotic differ?
You would NOT use Trimethoprim twice in 3 months as this can lead to antibiotic resistance. Prescribe Nitrofurantoin for another 3 day course.
What bacterium is the second most likely cause of UTI in young women and how does it enter the urinary tract?
Most likely cause in all women is E.Coli due to short urethra and displacement from rectum. Staphylococcus Saprophyticus is part of the normal genital tract and perineal flora of the female. Sexual activity can displace the bacterium into the urethra. Usually presents 24 hrs after sex, ‘honeymoon cystitis’.
Which bacterium is responsible for ‘honeymoon cystitis’? Describe its appearance on a gram stain and coagulase status.
Staphylococcus Saphrophyticus. Purple cocci (gram positive so purple). Coagulase negative. Staphylococci are either coagulase positive/negative. Coagulase enzyme required to make blood clot.
Casts in the urine are indicative of infection in what organ?
Kidneys because the casts are made in the nephron tubules. Blood cells enter the nephron and aggregate into the shape of the tubule, forming the cyclindrical casts.
What are coliform bacteria? Give a relevant example for UTI’s.
Rod shaped, gram negative bacilli present in the faeces of all mammals. They don’t usually cause infection. Their presence is often used as an indicator of water sanitation. E.Coli is a coliform and the most common cause of UTI in women.
Are you more likely to get a false-positive or a false-negative result using a urine dipstick?
Dipsticks are sensitive but not specific so more likely to get a false positive. This is perhaps better as less people are undiagnosed.
When and how does the EUS, external urethral sphincter open in healthy individuals?
When the individual decides to urinate because the EUS is striated muscle so under concious control. Less impulses along sympathetic somatic motor neurons (cause contraction of EUS) allow relaxation
What is normal bladder capacity in ml?
400-500 ml
Describe schistosoma haematobium infection - Infective organism - Pathogensis - Presenting complaints
- Urinary blood fluke (parasitic flatworm) that invades the urinary tract. Common in Africa and the Middle East. Enters the skin through infected water. (Case study; sudanese man). - Eggs deposited in the bladder cause fibrosis and calcification of the bladder (can’t accomodate large volumes of urine) - Presents as urinary frequency due to reduced bladder capacity, frank haematuria and nocturia
Why does prostatic hyperplasia often prevent a strong urine stream?
Hyperplasia in the transition zone (gets bigger) compresses the urethra so less urine can flow through at any one time (flow is proportional to radius^4). This also prevents the bladder emptying fully.
A woman has urinary incontinence. The frequency of action potentials has increased along which nerve pathway?
OVERACTIVE VOIDING REFLEX
She’s detecting a higher level of stretch in the bladder than is actually present so voiding in response. The stretch receptors are more active and more impulses along the sensory neurones from detrusor muscle to the sacral region (S2, S3, S4 keeps wee and poo off the floor).
Acute tubular necrosis is most commonly preceded by what?
Ischaemia to the renal tubules, often due to hypotension in hospitalised patients. Also in patients with ischaemic/ coronary heart disease (MI’s, angina are symptoms) where their blood flow is impaired by atherosclerotic plaque deposits.
Which types of kidney stones (calculi) are radiopaque and which are radioluscent?
Calcium phosphate and calcium oxalate stones are radiopaque (can be seen by X ray) and the most common stones to occur. Uric acid stones are radioluscent (can’t see on X ray) but uncommon.
Trimethoprim and Nitrofurantoin are given regularly as antibiotics for UTI infections. Which one cannot be given to men with an involved (infected) prostate?
Cannot give nitrofurantoin because it won’t reach therapeutic levels in the prostate and could drive the bacteria to develop resistance
Which is the first antibody at the scene of infection during the humoral response?
IgM is the first responder. IgG is present after the first infection.
How can Naproxen and Aspirin cause acute tubular/ kidney injury? CHECK
Both are NSAIDS which reduce the production of renal prostaglandins via reversible inhibition of the COX 1 and 2 enzymes. Prostaglandins (released by macula densa cells) cause dilation of the afferent arteriole to increase renal blood flow and GFR. *An importamt mechanism for maintaining GFR when renal blood flow is compromised*. With NSAIDS, the afferent vasoconstricts; the renal medulla can become ischaemic and GFR falls causing build up of waste products in the blood.
Why would someone who has D and V be more likely to suffer acute kidney injury following Naproxen administration?
This patient already has a compromised renal blood flow due to low blood volume so the action of prostaglandins on the afferent arteriole (vasodilation) is particularly important to maintain GFR. Naproxen (NSAID) inhibits prostaglandins synthesis so the patients GFR and renal blood flow fall leading to ischaemia?
What is Amlodipine used for?
It is an anti-hypertensive used to treat hypertension. It could cause low blood pressure and contribute to acute kidney injury.
When can you NOT administer metformin?
Metformin is used to treat Type 2 diabtetes mellitus. It reduces liver glucose production and glucose absorption from SI whilst improving sensitivity to insulin to prevent chronic hyperglycaemia. It can cause lactic acidosis so must never be given is there’s a risk of metabolic acidosis occuring; in acute kidney injury for example. (Kidney will reduce bicarbonate secretion and excrete less acid).
Rhabdomyolyisis can be caused by which drugs?
Statins
