Kidney and GU Flashcards
Describe the two types of kidney stones caused by hypercalcaemia
Calcium oxalate stones: black/ dark brown, radiopaque, form in acidic urine
Calcium phosphate: dirty white, radiopaque on x-ray, form in alkaline urine
Give 3 risk factors for calcium oxalate and calcium phosphate stones
Hypercalcaemia: Increased GI absorption/ hyperparathyroidism
Hypercalciuria: Impaired renal tubular reabsorption
Hyperoxaluria: Genetic defect causing increased oxalate excretion, defect in liver metabolism or diet heavy in oxalate-rich foods
Describe uric acid kidney stones
Red-brown
Radiolucent
Uric acid forms urate ion –> monosodium urate
Describe struvite kidney stones (infection stones)
Mg2+ Ammonium Phosphate Bacteria use urease to break urea down into carbon dioxide and ammonia (which makes urine more alkaline and favours precipitation) Dirty white/ radiopaque
Give 3 risk factors for struvite kidney stones
Urinary tract infections
Vasicoureteral reflux
Obstructive urpathies
Describe the pattern of pain with kidney stones
Dull/ localised flank pain in the mid-lower back
Renal colic
Pain due to dilation stretching and spasm, worse at uteropelvic pelvic junction
How would you diagnose kidney stones?
History and physical exam
Imaging: XR, CT, US
Urinalysis: microscopic/ gross haematuria
How would you treat kidney stones?
Hydration
Medication: analgesics, potassium citrate to reduce stone formation
Alpha adrenergic blockers/ CCB to help pass stones
Shockwave lithotripsy
Surgery/ stent placement
What is the usual BUN to creatinine ratio?
(5-20) : 1
Give 4 causes of absolute fluid loss leading to decreased blood flow in pre renal AKI
Haemorrhage
Vomiting
Diarrhoea
Severe burns
Give 2 causes of relative fluid loss leading to decreased blood flow in pre renal AKI
Distributive shock
Congestive HF
Give the equation for GFR
Blood filtered (ml) / minute
Describe the effect of reduced GFR in pre renal AKI
Less urea and creatinine filtered therefore more in the blood (azotemia)
Oliguria: low urine
RASS activated
Water and sodium reabsorption is tied to urea reabsorption therefore BUN: creatinine is >20:1
Give the percentage of sodium excreted compared to sodium filtered in pre-renal AKI
<1%
How is urine concentration affected in pre-renal AKI
More concentrated urine, Uosm >500 mOsm/ kg
Where is the damage in intrarenal AKI?
Tubules
How can the tubules become damaged causing intrarenal AKI?
Acute tubular necrosis (due to pre-renal AKI) Nephrotoxins: Aminoglycosides (Abx) Lead Myoglobin Ethylene glycol Radiocontrast dye
What is tumour lysis syndrome and how can it cause intrarenal AKI?
Uric acid is released during cancer treatment, excess uric acid damages the tubules
How would you treat intrarenal AKI?
Hydration (improves from)
Medications:
Allopurinol
Urate oxidase
How does the necrosis of cells in intrarenal AKI cause problems in the kidney?
Dead cells slough off and clog the tubules, increasing pressure
There is a decrease in GFR: oliguria, azotemia
Hyperkalaemia and metabolic acidosis since dead cells are not absorbing
Dead cells form a brown granular cast
How does glomerulonephritis cause intrarenal AKI?
Antigen-antibody complexes are deposited in tubules
Activates the complement system, other immune cells are attracted with lysosomal enzymes which cause damage
Increase the permeability of podocytes so large molecules can pass through
What is the effect of fluid leakage due to tubular damage in intrarenal AKI?
Reduced pressure difference, reduced GFR, causing: oedema, HTN, oliguria, azotemia
Describe acute interstitial nephritis including symptoms
Infiltration of immune cells (type I or IV hypersensitivity) causing oliguria, eosinophiluria, fever, rash
Give 3 causes of type I or Iv hypersensitivity in acute interstitial nephritis
NSAIDs
Penicillin
Diuretics
What complication can occur secondary to type I or IV hypersensitivity in acute interstitial nephritis?
Renal papillary necrosis, causing haematuria and flank pain
Give 4 causes of renal papillary necrosis other than acute interstitial nephritis
Chronic analgesic use
Diabetes mellitus
Sickle cell disease
Pyelonephritis
How would BUN : creatinine ratio appear in intrarenal AKI?
Kidney can’t filter, so reabsorption/ secretion is impaired so urea is not reabsorbed
<15 : 1
How is urea sodium affected in intrarenal AKI?
Sodium is not reabsorbed so UNa >40mEq/l
% of filtered excreted is > 2%
Describe post-renal AKI
Obstruction to outflow due to compression (intra-ado tumours or BPH) or blockage (kidney stones in urea/ urethra)
How does outflow obstruction in post-renal AKI affect GFR?
Buildup of urine and pressure in renal tubules, reduces pressure gradient and therefore decreases GFR causing azotemia and oliguria
How does the a high pressure tubule in post-renal AKI affect reabsorption initially and then after a period of time?
Increased reabsorption of sodium, water and urea
BUN : creatinine >15 : 1
% sodium filtered excreted is < 1%
Constant pressure leads to cell damage and reduced reabsorption
BUN : creatinine <15 : 1
% sodium filtered excreted is >1-2%
Where do renal cell carcinomas form from and why are the tumours yellow?
From epithelial cells in the proximal convoluted tubules and are filled with cytoplasm of carbohydrates and lipids (yellow)
How do renal cell carcinomas form?
Mutation on VHL tumour suppressor gene, so IGF-I (growth factor) is increased leading to unregulated cell growth and up regulation of vascular endothelial growth factor and receptor (VEGF) -> angiogenesis
Describe the typical sporadic case of renal cell carcinoma
Solitary tumours in the upper pole of the kidney
Older men
Smokers
Give an inherited syndrome that can cause renal cell carcinoma
Von Hippel-Lindau disease
Autosomal dominant mutation that causes the formation of cysts and being tumours, often in both kidneys
Younger men/ women
Give 4 symptoms of renal cell carcinoma
Flank/ hip pain
Palpable mass (abdomen/ lower back)
Haematuria
Inflammation (fever and weight loss)
Describe the paraneoplastic syndromes associated with renal cell carcinoma
Erythropoietin production causing polycythemia, therefore slugding/ slow flow
Renin release increases BP
PTHrP causes hypercalacemia
ACTH (adrenocorticotrophic hormone) causes an increase in cortisol and therefore can cause Cushing’s syndrome
How can a varicocele occur as a result of renal cell carcinoma?
If the tumour is of the L kidney it may compress the L renal vein and impede venous drainage of the L testes causing testicular veins to dilate
What is the risk of a renal cell carcinoma invading the renal vein?
Spreads to the IVC, there is therefore a high risk of cancer spreading in the blood stream, particularly to the bone and lungs
How would you stage a renal cell carcinoma?
T: size/ grown into nearby areas
N: lymph node involvement
M: degree of metastasis
0-4 score
How would you treat renal cell carcinoma?
Resistant to chemo/ radiotherapy
If localised may be resection
Sensitive to immune system therefore:
Immunomodulatory agents (chemokines/ antibodies)
Molecular targeted therapy (VEGF) : cut off blood supply
Where does a transitional cell carcinoma most commonly arise?
Urothelium of the bladder
Describe the structure of the bladder wall
Urothelium (3-7 layers)
Basal, intermediate and umbrella layer
Tight junctions in intermediate layer
Plaques over umbrella layer/ umbrella cells give bladder the ability to stretch
Describe the role of P53 in causing transitional cell carcinoma
P53 dependent: (mutation) flat tumour, invasive
P53 independent: less aggressive papillary tumour
How would you diagnose a transitional cell carcinoma?
Cystoscope (light and camera, can take biopsies)
Haematuria
Why are transitional cell carcinomas difficult to treat?
Multifocal, can recur
Tumour cells may detach from one location and implant themselves at another in the bladder
Give 4 risk factors for transitional cell carcinoma
Age
Carcinogenesis (phenacetin, smoking, aniline, cyclophosphamide)
Alcohol abuse
Extended dwell times
How would you treat transitional cell carcinoma?
Tumours may be resected with a cystoscope/ transurethral resection
Followed with chemo
Aggressive cancer may require removal of the prostate and bladder
Give 3 risk factors for prostate cancer
Age
Afro-caribbean
Genetics
How would prostate cancer present?
Raised PSA Weak stream Hesitancy Incomplete emptying Increased urinary frequency Urgency
Give 6 possible signs of prostate cancer
General malaise Bone pain Anorexia Weight loss Obstructive neuropathy Paralysis: cord compression
Give 5 features of a malignant prostate on DRE
Lack of mobility Asymmetrical gland Nodule with one lobe Induration of part/ all prostate Palpable seminal vesicles
Give 4 systemic symptoms of prostate cancer
Blood in semen
ED
Pelvic discomfort
Bone pain and stiffness
Give 4 conditions in which you might see an elevated PSA
BPE, UTI, prostatitis, prostate cancer
How would you diagnose prostate cancer?
LUTS
PSA
Transrectal US
Prostate biopsy
How would you stage prostate cancer?
TNM
Gleason score
How would you manage prostate caner?
Localised: acute surveillance
Locally advanced: radial prostatectomy, radiotherapy and androgen deprivation therapy
Metastatic: bilateral orchidectomy, prostatectomy and radiation therapy
Give 3 risk factors for testicular cancer
Cryptorchidism
FHx
Previous testicular tumour
How would testicular cancer present?
80% painless lump in the testes (hard/ craggy, lies within testis, can be felt above)
Hydrocele: may contain bloodstained fluid
Pain: unexplained in one testis
Metastases: grows in the lung; abdominal mass due to enlarged para-aortic lymph nodes; cervical nodes
How would you diagnose testicular cancer?
USS same day CXR if resp. symptoms Staging CT Tumour markers: AFP B-hcg LDH
How would you manage testicular cancer?
Orchidectomy if malignant
Seminomas are radiosensitive
Teratomas are treated with cytotoxic chemo.
What is the major implication in testicular cancer treatment?
Sterility
Describe CKD
Subtle decreased in kidney function over >3 months
Give the value of a healthy GFR
100-120ml/min/1.73m3
How can HTN cause CKD?
Walls thicken in order to withstand the pressure, narrow lumen so less blood is reaching the kidney: Ischaemic injury
Immune cells damage the glomerulus and secrete growth factor such as TGF-B1, this causes mesangial cells to regress to mesangioblasts which secrete extracellular matrix, causing glomerulosclerosis (scarring)
How can diabetes cause CKD?
Excess glucose in the blood sticks to proteins
(Non-enzymatic glycation, causes hyaline arteriosclerosis of efferent arteriole)
Difficult for blood to leave the glomerulus and increases pressure causing hyper filtration
Mesangial cells secrete extracellular matrix, increasing glomerular size and causing sclerosis
Give a systemic, infective, medicinal and toxin cause of CKD
Lupus/ rheumatoid arthritis
HIV
NSAIDs
Tobacco
Describe the consequences of decreased urea excretion as a result of CKD
Buildup in blood causing nausea, loss of appetite, encephalopathy: asterixis (tremor of the hand) : coma and death
Can also cause uraemic frost, pericarditis and bleeding
Describe the consequences of decreased potassium excretion as a result of CKD
Buildup in blood causing cardiac arrhythmias
Describe the consequences of less activated vitamin D as a result of CKD
Less calcium absorbed causing PTH release so the bones lose calcium causing renal osteodystrophy
How can CKD cause anaemia?
Reduced erythropoietin levels
How would you diagnose CKD?
Changes in GFR over time ( <90ml/min/1.73m3)
Irreversible damage ( <60ml/min/1.73m3)
Biopsy: look for glomerulosclerosis
How would you treat CKD?
Manage underlying cause
Dialysis
Transplant
Describe benign prostate hyperplasia
Non-cancerous increase in size of the prostate
Give 3 storage symptoms of BPH
Increased frequency
Nocturia
Involuntary urination
Give 5 voiding symptoms of BPH
Urinary hesitancy Intermittency Weak stream Incomplete emptying sensation Terminal dribbling
Give 5 symptoms of bladder outlet obstruction secondary to BPH
Abdo pain Feeling of a full bladder Frequent urination Acute urinary retention Dysuria Urinary hesitancy
How can BPH cause an increased risk of UTI?
Incomplete voiding results in urinary stasis
How would you diagnose BPH?
History of LUTS
DRE
Exclusion of other causes of similar symptoms
Urinalysis
Describe the medicinal management of BPH
Alpha blockers: Alfuzosin, tamulosin (relax smooth muscle in prostate and bladder neck, reducing the blockage of flow)
5-alpha reductase inhibiters: Finasteride (Inhibits 5-alpha reductase which inhibits DHT- hormone responsible for prostate enlargement)
Describe the lifestyle changes suggested to manage BPH
Physical activity
Moderate alcohol and caffeine consumption
Avoid meds with anti-cholinergic properties
Elderly men: seated voiding position
Describe acute pyelonephritis
Inflammation of the renal pelvis, usually unilateral
Describe the causes of acute pyelonephritis
Ascending infection
Vesicoureteral reflux if vericoureteral orifice fails and urine moves up the urinary tract, creating a one way valve from the ureter to the bladder
This may be caused by a primary congenital defect or bladder outlet obstruction
Give 5 risk factors for acute pyelonephritis
Female Sexual intercourse Indwelling catheter Diabetes Urinary tract obstruction
Give 3 types of bacteria that commonly cause ascending infection in acute pyelonephritis
E. coli
Proteus
Enterobacter
Give 3 ways in which a haematogenous infection can cause acute pyelonephritis
Septicaemia
Bacteremia
Infective endocarditis
Why are dead neutrophils and WBC casts found in the urine of a patient with acute pyelonephritis?
Bacteria adheres to tubules epithelium which attracts neutrophils to infiltrate
Give 5 symptoms of acute pyelonephritis
Fever Nausea and vomiting Chills Leukocytosis Flank pain @ costo-vertebral angle
Give the treatment for acute pyelonephritis
Abx
Hydration
Describe the complications which may occur as a result of acute pyelonephritis
Renal abscess
Recurrent infections: from anatomic problem, chronic pyelonephritis, papillary necrosis
Give 5 general causes of cystitis
Bacterial infection Fungal infection Chemical irritants Foreign bodies Trauma
Give 3 gram negative bacteria that may colonise the bladder mucosa in cystitis
E. coli Klebsiella Proteus Enterobacter Citrobacter
Give 2 gram positive bacteria that may colonise bladder mucosa in cystitis
Enterococcus
Staph. saprophyticus (second most common, esp. in sexually active young women)
Give 5 risk factors for cystitis
Sexual intercourse
Female (short urethra, post-menopausal: decrease in oestrogen, loss of protective vaginal flora)
Foley catheter
Diabetes: hyperglycaemia inhibits phagocytosis
Infant boys with foreskin
Impaired bladder emptying
Give 4 symptoms of cystitis
Suprapubic pain
Dysuria
Frequent urination
Urgency
Give 3 signs of cystitis found on urinalysis
Pyuria- cloudy
Leukocyte esterase
Positive for nitrites (if caused by gram -ve since gram -ve bacteria convert nitrates to nitrites)
Describe the results of a urine culture in cystitis
Positive if >100,000 CFU/ml
What might be suspected if a urine sample was positive for pyuria but gave a negative urine culture?
Sterile pyuria
Suggests urethritis, may be due to:
Neissariae gonorrhoea
Chlamydia tricomitis
How would you treat cystitis?
Abx
Pain medication
Prevention: lots of fluid and good hygiene
Give 5 acute symptoms of prostatitis
Pain in/ around penis, testicles, anus, lower abode Urinary symptoms Acute urinary retention General malaise Fever Discharge
Give 3 chronic symptoms of prostatitis
Englarged/ tender prostate on DRE
ED, pain when ejaculating, pelvic pain after sex
What is the cause of prostatitis?
Bacteria from the urinary tract enters the prostate
Give 5 risk factors for prostatitis
Having a UTI in the recent past Catheter Prostate biopsy STI HIV/ AIDS Anal sex Pelvic injury
How would you treat acute prostatitis?
2 week course of Abx
How does nephritic syndrome occur in glomerulonephritis?
Damage means that small pores in the podocytes become large enough to allow proteins and RBCs into the urine
Give 3 causes of nephritic syndrome in children/ adolescents
IgA nephropathy
Post-strep glomerulonephritis
Haemolytic ureic syndrome
Give 4 causes of nephritic syndrome in adults
Good pasture syndrome
SLE
Rapidly progressing glomerulonephritis
Infective endocarditis
Give 5 signs/ symptoms of nephritic syndrome
Haematuria Proteinuria HTN Blurred vision Azotemia Oliguria
How would you diagnose nephritic syndrome?
Blood electrolytes BUN K+ Protein in urine Urinalysis Kidney biopsy
How would you treat nephritic syndrome?
Anti-hypertensives
Anti-inflammatory meds
Low potassium and salt diet
Describe nephrotic syndrome
A collection of symptoms due to kidney damage: Proteinuria Hypoalbuminemia Hyperlipidaemia Oedema Lipiduria
Why would nephrotic syndrome present with hyperlipidaemia?
Hypoproteinuria stimulates protein synthesis in the liver leading to the overproduction of lipoproteins
There is also a decrease in lipid catabolism due to the low lipase levels
Give 5 symptoms of nephrotic syndrome
Anaemia Dyspnoea High ESR Frothy urine Puffiness around the eyes
Give 5 causes of nephrotic syndrome
Minimal change disease Focal segmental glomerulosclerosis Membrane glomerulonephritis Membranoproliferative glomerulonephritis Rapidly progressive glomerulonephritis
Describe polycystic kidney disease
Genetic disease causing the cortex and medulla of the kidneys to become filled with hundreds of cysts
How might polycystic kidney disease cause HTN?
Blood vessels of neighbouring nephrons can be compressed by cysts causing ischaemia
RAAS activation leads to HTN
How can polycystic kidney disease cause kidney stones?
Expanding cysts can compress the collecting system, this causes urinary stasis which is a risk factor for developing kidney stones
Give 2 general symptoms of PKD
Flank pain
Haematuria
Give the two possible mutations for PKD and state which is more severe and earlier onset
Both autosomal dominant
PKD1: More severe and earlier onset
PKD2
What is the result of the absence of a normal PKD1 or PKD2 protein?
Signal to inhibit cell growth won’t be received
Cells proliferate abnormally and express proteins that allow water into the lumen of the cysts
Give 4 parts of the body in which cysts can form in PKD other than the kidneys
Liver
Seminal vesicles
Pancreas
Vasculature (aortic root dilation/ berry aneurysm)
How does autosomal recessive PKD differ from autosomal dominant PKD?
ARPKD
Renal failure before birth, less foetal urine, oligohydraminos (low amniotic fluid)
Can cause Potter’s syndrome (developmental abnormalities) such as clubbed feet, flattened nose, pulmonary hypoplasia
How would you diagnose PKD?
Prenatal US
Bilaterally large kidneys
Cysts
Oligohyraminos
What is the result of congenital hepatic fibrosis in ARPDK?
Portal HTN: Oesophageal varices Upper GI bleeds Haemorrhoids Splenomegaly
How would you treat PKD?
HNT: ACE inhibitors, angiotensin receptor blockers
Cholestasis: Ursodiol
Renal failure: Dialysis, transplant
Portal HTN: Portocaval shunt, transplant
Describe a spermatocele
Retention cyst of a tubule of the rete testis/ head of epididymis, distended with fluid, containing spermatozoa
Give 3 causes of a spermatocele
Epididymitis
Physical trauma
Vasectomy
How would you diagnose a spermatocele
US to rule out malignancy
When might a spermatocele be removed?
If cysts are causing discomfort/ are enlarging in size
Describe a hydrocele
Accumulation of serous fluid around a testicle
Give 3 causes of a hydrocele
Fluid secretion from the tunica vaginalis
Defective absorption of fluid
Interference of lymphatic drainage
How would you diagnose a hydrocele?
Transillumination +ve
Fluctuation +ve
Impulse on coughing -ve
Describe a varicocele
Abnormal enlargement of the pampiniform venous plexus in the scrotum
How might a varicocele present?
Noticed as soft lumps, usually above the testicle, most commonly on the left, can sometimes be painful/ felt as heaviness
What is the main risk/ complication of a varicocele?
Male infertility
How would you diagnose and treat a varicocele?
US: dilation of the vessels
Treatment: microscopic surgery, percutaneous embolism
