Infections, stones and cancers Flashcards
State 3 host factors which increase risk of UTIs
- short urethra (women)
- Obstructions
- Neurological problems (incomplete emptying)
State 3 virulence factors of E. Coli which means it can cause UTIs
- Its part of faecal flora, so can easily get there via perineurium
- It has fimbrae and adhesins on its surface which allow attachment to urethra and bladder epithelium - K antigens; polysaccharide capusle allows e.coli to evade host defences
- Urease: breaks down urea to make a favourable environment for itself
What is abacterial cystitis/ urethral syndrome? what may cause it?
Where women have symptoms of a UTI but no bacteria is found in the urine cultures. This could be due to an infection with low bacterial count, STIs (chalmydia) or non infectious inflammation (eg from chemicals).
Of all women with cystits symptoms, what % have bacterial and what % have abacterial cystitis?
50% bacterial and 50% abacterial
What is cystitis inflammation of? What are the symptoms of it?
Dysuria (painful urination- burning sensation), frequency, pyuria (pus in urine) and haematuria can also be present
What are the signs and symptoms of prostatitis?
fever, dysuria, frequency, perineal and lower back pain
What acute pyelonephritis and what are its signs and symptoms?
Bacterial infection of renal parenchyma. Same signs and symptoms of lower UTIs + fever and rigors, loin pain, quite commonly progresses to sepsis.
What is chronic interstitial nephritis?
Renal impairment following chronic inflammation, with infection being one of the many causes
What is covert bacteriuria?
Bacterial infection, which doesnt cause symptoms but is detected only by culture
Define uncomplicated UTIs
An infection by a usual organism in a normal urinary tract and normal urinary function. You can get them in M or F of any age.
What is a complicated UTI? Give examples of them
Having a predisposition to persistant infection, having recurrent infections or treatment failure. This may be caused by abnormal urinary tracts (indwelling catheters), virulent organisms (staph A), impaired host defences (diabetes, immunosurpression), impaired renal function
Why are UTIs in men, children and cases of pyelonephritis managed at complicated UTIs even though they meet the definition of uncomplicated?
Because they shouldn’t really happen in men, so investigations are needed to make sure there isn’t anything else wrong/ more targetted treatment may be needed. Pyleonephritis has high risk of sepsis and so needs more investigations and targeted management
How should UTIs be investigated? (3)
- Urine dipsticks
- urine sample (look at colour/ frothiness/ cloudiness)
- Urine samples from complicated UTIs should go to lab for microscopy and sensitivity testing
What results on a urine dipstick would indicate a UTI?
- Raised nitrates
- Raised leucocyte esterase
- Cloudy urine (not on dipstick but can be seen)
- blood or protein may also be detected Uncomplicated UTIs are often negative for all of these, you also get lots of false negatives in catheterised pts
What is sterile pyruria and what can cause it? (3)
WBCs are found in urine but not bacteria May be caused by:
- prior antibiotics
- Urethritis (STDs)
- Vaginal infection or inflammation (contaminates sample)
- non infective inflammation (cancer, chemical irritants)
- urinary TB
How are uncomplicated lower UTIs treated? (length of course + name 2 meds used + supportive treatment advice)
- Three day course of trimethoprim or nitrofurantion - increase fluid intake
- NSAIDs or paracetamol for pain
How are complicated ower UTIs treated?
5-7 day course of trimethoprim, nitrofurantion or ceftriaxone + increase fluids and paracetamol
How are UTIs in ppl with catheters treated?
- Antibiotics only indicated if they get systemic symptoms
- they should get better after removing and replacing the catheter
How is pyelonephritis treated?
10-14 days of trimethoprim (not nitrofurantion because this doesnt work systemically and there is sepsis risk) or co- amoxiclav or ciprofloxacin
When is action taken to treat asymptomatic bacteruria?
pregnant or about to undergo surgery
How are recurrent UTIs treated? (>3 p/y)
Antibiotic prophylaxis can be taken, but resistance is forming
What structural issues may cause children to have recurrent UTIs? (3)
- Presence of posterior urethral valves (mainly in boys) where there is a membrane blocking outflow of urine from the bladder
- Vesicoureteric reflux (causes hydonephrosis, may be due to posterior urethral valves, obstructions ect)
- Duplex ureters (two ureters coming from one kidney to the bladder)
What is a consequence of repeated pyleonephritis?
cysts and scarring of renal parenchyma
What consequences will TB spreading to the urinary tract have?
- may cause caseous necrosis (and so calcification) and abcesses in the kidneys
- may get sterile pyuria, haematuria
- may spread to ureters or bladder
- generally slow and progressive but treatable
What is schistomiasis haematobium?
A parasite which can lay dormant in the bladder for yrs before causing chronic cystits, calcification of the bladder and squamous cell bladder cancer
Which infection causes glomerular nephritis in 20% of cases?
Endocarditis, usually due to step viridans or staph areus. The AKI may occur due to this or the antibiotics or septic emobli as a result of the infection
What other infections can cause GN?
- Group A strep infections (Nephritic syndrome 1-4 weeks post throat infection)
- Hep B and C
- TB
- HIV
- Syphilis
- Malaria
What factors increase risk of infection in CKD? (5)
- co morbities such as diabetes
- immunosurpression (for treatment of cause or transplants)
- less vaccine resposivness
- malnutrition
- nephrotic syndrome
- decreased immune reponse
- lots of hospital visits= increased exposure
- theyre generally old age
- plastic catheters and needles if on dialysis
What infections are more common in CKD?
- cellulitis
- chest infections
- Gi infections
- UTIs
Give 3 reasons that pts receiving kidney transplants are at higher risk of infection
- on immunosurpression
- surgery
- reactivation of latent infections in the donated organ (HSV, Hep B& C, TB, CMV)
- in UK these are screened but not everywhere
What % of those with visible haematuria will have no abnormality and what % will have cancer?
40% no abnormalities after further investigations 20% have cancer
What % of the population have invisible haematuria and dont know it?
15%- most of these people will have no abnormality
What can cause haematuria? (6)
- Cancers
- Stones
- Infections
- inflammation
- large BPH
- sickle cell anaemia
- Haemophillia
- Anticoagulants
- Nephritic syndromes (IgA nephropathy ect)
What further investigations would be done for haematuria?
History Urological examination (abdomen, palpable bladder, genitalia, neurology) Flexible cystoscope Ultrasound/ CT Urine dipsticks, microscopy and cytology
What may cause orange urine?
Rifampicin (TB med), excess vit B and vit C
What may cause urine to go red, other than blood?
Beetroot, rubarb, phenolpthaline, rifampicin, some laxatives
What would cause dark urine?
posthepatic jaundice
How can you differentiate between acute and chronic urinary retention?
Acute is painful, fast onset
How should acute urinary retention be managed?
Investigations: Bloods, bladder USS, neuro exam Treatment: Immediate catheterisation to avoid long term damage, then treat cause
What 3 general mechanisms may cause acute urinary retention?
bladder outlet obstruction, low bladder contractile power, nervous interruption
What may cause acute urinary retention in men only? (4)
- BPH
- Prostate cancer
- Urethral stricture
- postatitis
What may cause acute urinary retention in women only? (4)
Prolapses masses post botox for stress incontinance fowler syndrome (young women who cant relax EUS)
What may cause acute urinary retention in either men or women? (5)
- clots - drugs (anti cholinergics, sympathmiometics, spinal anaesthetics) - pain - surgery - spinal cord injuries - infections - urethral damage or rupture - neurological degeneration - Consiptation - diabetic cystopathy
How can chronic urinary retention be confirmed/ diagnosed?
Urine will be seen on a post void residual USS scan.
Whats the difference between high and low pressure chronic urinary retention?
high pressure (Pves >30 cmH2O) is more dangerous as impaires renal function and they need catheterisation until theres a definitive management plan
Whats is the difference in fluid volume drained from someone with acute on chronic urinary retention and someone with acute urinary retention?
Acute on chronic urinary retention will drain >800ml of urine, because their bladder has distended and become larger due to chronic overfilling
Other than urinary retention, when else might you catheterise and why?
sepsis and trauma to monitor urine output
When might suprapubic catheters be opted for?
Long term use- eg in MS. You need to use USS guidance for these though due to risk of perforating the bowel
Where are the most common places to get urinary tract stones?
- kidney, uterter and bladder common
- Urethra quite rare and only in men
How may renal calculi present?
- SEVERE, often colicy lower pain/ abdo pain radiating to flanks
- Haematuria, infection, urinary retention
List 5 risk factors for kidney stones
- middle age - caucasian or indian - sedentary lifestyle - chronic dehydration - past stones (50% recurrence rate) - summer months (more dehydrated, more vit D)
What is the commonest type of kidney stone and how does it form?
Calcium oxalate (85% of all stones) Due to high calcium in urine (familial, or due to hyperparathyoidism) or just generally having more concentrated urine (dehydration) leading to crystalisation
How do uric acid stones form?
High levels of uric acid+ dehydration and stagnation= uric acid crystals- common in body builders (high protein= high urea+ dehydration). Also common in gout sufferers.
How do calcium oxalate & calcium phosphate combination stones form?
Type 1 renal tubular acidosis = H+ staying in tubule and not going into urine, the Ca2+ and PO4-2 react with the alkaline urine causing precipitation and so stones. (this is rare)
How do struvite stones form? What are they made from?
Theyre made from magnesium ammonium phosphate. They form due to urea being converted to ammonia by urease from infectious organisms, the ammonia makes the urine alkaline and so allows preciptation
When do cysteine stones form?
in those suffering from homocystine urea, the high concentrations of cystine cause precipitation so stones
How are kidney stones investigated?
Most seen on abdo x ray Non contrast CT Dipstick to find blood USS may be used
What are the differentials for a kidney stone?
testicular torsion
billary colic
ruptured AAA
pyelonephritis
acute pancreatitis or appendicitis
sigmoid volvulus
gut ischaemia
How are renal calculi managed?
- if <4mm conservatively manage as it will pass - Extracoporeal shockwave lithtotripsy can help break it down
- cystoscopy + URS+ laser tripsy or percutaneous nephrolithotomy can also be done
- Asses sepsis risk
What is the name for the pathology in the AXR shown?
Staghorn calculi
What type of cancer is found in the renal cortex or medulla?
renal cell carcinoma (RCC)
What type of cancer is found in the calyx, ureter, bladder or urethra?
Transitional cell carcinoma (TCC)
When might you get squamous cell carcinoma of the bladder?
W/ history of chronic inflammation- schistomiasis, long term catheters
How may RCC present?
- haematuria (usually visible)
- indicental finding on USS or CT
- Rarely a palpable mass
- if advanced- large varicocele, pulmonary tumour emboli, loss of weight, hypercalcaemia
Which demographic is affected most by RCC and TCC?
M more than F and white more than non white
What are the 3 biggest risk factors for RCC?
smoking
diabetes
dialysis
What 3 ways can RCC spread?
Phrenic spread- into fat nearby, from here it can get into duodenum and colon
Through IVC to right atrium, from here it can embolise to the lungs
Lymph node mets
Perinephric spread-
How is imaging used for RCC diagnosis and staging?
USS will normally show it, if USS positve, CT is needed to stage it
How is RCC treated?
If localised: surveillance (may never be an issue) or excise or albate it (freeze/ radiowaves to destroy it)
If metastaic: biological therapies (sunitinib will inhibit tyrosine kinase and this is effective). RCC tends to be resistant to chemo and radiotherapy
How can you tell thats a renal cell carcinoma?
Clear cells present- cells filled w/ glyogen. These are quite characteristic of RCC
How do bladder TCCs present?
haematuria
incidental finding
loss of weight, DVT, lymphodema if advanced
Why do women with TCC tend to get diagnosed later?
In them, haematuria is often initialy dismissed as UTI
What are biggest risk factors for TCC?
- Smoking
- occupation - handling of carbon, crude oil, painters, mechanics, printers (2- napthyl amine)
How are bladder TCCs staged?
On a scale of T1- T4
T1 is superficial, T2,3 and 4 are more invasive.
How are high stage, high grade TCCs treated?
Neoadjuvant chemo + radical cystectomy or radiotherapy.
What cancer does phentacin abuse mainly predispose to?
Upper tract TCCs
What investigations are done for TCCs?
- USS (often shows hydronephrosis)
- CT urogram (shows filling defects, strictures ect)
- Retrograde pyelogram
- Uteroscopy (for biopsy and cytology washings)
How can upper tract TCCs be treated?
Nephro- uterectomy (remove kidney, fat, ureter and cuff of bladders)
If metastsic: cis-platin based chemo if kidney function still ok, of immuno therapy if poor kidney function
How does prostate cancer present?
- urinary symptoms (retention, poor flow, nocturia, polyuria ect)
- bone pain (can cause osteoblastic bone disease)
- Had their PSA checked then got a biopsy
- Had DRE for another reason
- Incidental finding at trans urethral resection of prostate for urinary symptoms
What are the 3 biggest risk factors for prostate cancer?
old age
familly history (significant if they were diagnosed before 60)
black> white> asian
How is prostate cancer diagnosed?
PSA high or DRE positive and then TRUS (transurethral ultrasound guided) biopsy to confirm
Other than prostate cancer, what can cause a raised PSA?
infection, inflammation, BPH, urinary retention
What will affect descision to treat a prostate cancer? (5)
- Age (if > 70 it probably wont kill them)
- DRE (can normally tell if localised, locally advanced or advanced)
- PSA level
- Grade (high grade generally more severe and more likely to kill them)
- MRI and bone scan (can see if it has metastasised)
How are advanced prostate cancers treated?
- Hormones +/- chemo
- surgical or medical castration with LHRH agonist
- Prostatectomy
- palliation w/ single dose chemo and radiotherapy
How does an LHRH agonist cause medial castration?
makes GnRH relase constant, initialy causes a testosterone spike but then it negatively feeds back and causes drop in testosterone levels
Which cancers commonly metastasise to bone?
Breast
kidney
thyroid
lung
prostate
Are prostatic bone mets osteoblastic or osteolytic?
Theyre the only type which are oestoblastic
What is the second commonest causative organism of UTIs?
staphylococcus saprophyticus (coagulase negative, gram positive diplococcus)
