Renal and Urology Flashcards
Define Urinary Tract Infection
An infection of the kidneys (upper UTI), bladder, urethra or prostate (prostatitis) (lower UTI). Infectious cystitis (bacteral infection of bladder) is the most common type of UTI.
The presence of a pure growth of > 105 organisms per mL of fresh MSU
What is pyelonephritis and which signs and symptoms are suggestive of this?
Infection of the kidney that often occurs via bacterial ascent
Costovertebral angle tenderness and fever
What is the difference between complicated and uncomplicated UTI?
Uncomplicated UTI: normal renal tract and function
Complicated UTI: abnormal renal/genitourinary tract, voiding difficulty/obstruction, reduced renal function, impaired host defences, virulent organism (e.g. S. aureus)
Describe the aetiology of urinary tract infection
Transurethral ascent of organisms following colonisation of the vagina.
Amplified by factors that promote the introduction of bacteria at the urethral meatus.
Stasis of bladder urine impairs the defence against infection provided by bladder emptying.
Uncomplicated UTI:
Escherichia coli is the most common cause of uncomplicated UTI (70-95% of cases)
Staphylococcus saprophyticus
Enterobacteriaceae eg Klebsiella, enterococci, group B streptococci, Pseudomonas aeruginosa
Atypical organisms that can cause UTI (in immunocompromised individuals):
Klebsiella
Candida albicans
Pseudomonas aeruginosa
What are the risk factors of urinary tract infections?
Female Sexual activity Spermicide use Pregnancy Post-menopause Family history of UTIs History of recurrent UTIs Presence of a foreign body eg catheterisation Immunosuppression Urinary tract obstruction eg stone, stricture
Insulin-treated diabetes
Recent antibiotics
Poor bladder emptying
Increasing age
Summarise the epidemiology of urinary tract infections
10% of women over 18 report at least one suspected UTI a year 20-40% of women develop recurrent UTIs VERY COMMON More common in women Rarely cause significant renal damage
What are the presenting symptoms of a urinary tract infection?
Cystitis: Increased urinary frequency Increased urinary urgency Dysuria Suprapubic pain Haematuria Smelly cloudy urine
Prostatitis: Flu-like symptoms Fever Low back pain/perineal Few urinary symptoms Swollen or tender prostate on PR Urgency Hesitancy Intermittency Post-micturition dribbling Poor Stream
Acute Pyelonephritis: High fever Malaise Vomiting and rigors Back/Flank pain Loin pain and tenderness Oliguria (small amounts of urine - if AKI) Urinary symptoms similar to cystitis Costovertebral angle tenderness
Elderly: Malaise Nocturia Incontinence Confusion
What are the signs on physical examination of urinary tract infections?
Cystitis: Fever Suprapubic tenderness Bladder distension Foul-smelling urine
Pyelonephritis:
Fever
Loin/flank tenderness
Prostatitis:
Tender, swollen prostate on DRE
What are the appropriate investigations for urinary tract infections?
Urine dipstick - positive for nitrites and leukocyte esterase, blood, protein
Urine microscopy - confirm organism to allow antibiotic selection - bacteria, WBCs, RBCs
Urine culture and sensitivity - growth of >10⁵ CFU/mL
Ultrasound: Rule out obstruction
Renal USS – exclude structural abnormalities in women with recurrent UTIs, children, men
Bloods: FBC, U&Es (renal function), CRP, blood cultures (systemically unwell/urosepsis risk)
What is the management of urinary tract infections?
Oral antibiotics: TRIMETHOPRIM or NITROFURANTOIN
Treat for 3-6 days
Men with UTI may need a longer course of antibiotics
Alternative antibiotics: Co-amoxiclav or Cefalexin
Co-trimoxazole
Amoxicillin
Ciprofloxacin
IV gentamicin, cefuroxime or ciprofloxacin in pyelonephritis plus paracetamol
Prevention: High fluid intake Regular micturition (esp. after sex) Cranberry juice Low dose prophylactic antibiotic therapy inrecurrent UTI in recurrent cystitis associated with intercourse
What are the possible complications of urinary tract infections?
Sepsis Renal and peri-renal abscess Acute kidney injury Emphysematous pyelonephritis - acute necrotising renal infection commonly in immunocompromised older Xanthogranulomatous pyelonephritis Pyelonephritis Hydronephrosis or pyonephrosis Prostatic involvement (e.g. prostatitis)
What is the prognosis of urinary tract infections?
Very good prognosis
Most resolve with treatment
With appropriate antimicrobial treatment and resolution of symptoms, there is unlikely to be long-term sequelae.
Define benign prostatic hyperplasia
Slowly progressive nodular hyperplasia of the periurethral/transitional zone of the prostate gland, causing lower urinary tract symptoms due to bladder outlet obstruction (voiding/obstructive & storage symptoms).
Summarise the aetiology of benign prostatic hyperplasia
Aetiology is unknown
Shifts in age-related hormones may cause androgen/oestrogen imbalances
Risk factors: Age >50 years old Family history Non-Asian race Cigarette smoking Metabolic syndromes
Summarise the epidemiology of benign prostatic hyperplasia
Common
Affects 82% of men between 71-80 years old
50% of men with BPH will experience symptoms
Prevalence increases with age
More common in the West
More common in Afro-Carribeans
What are the presenting symptoms of benign prostatic hyperplasia?
Storage symptoms:
Frequency
Urgency
Noturia
Voiding symptoms: Hesitancy Dysuria Weak stream Intermittency Incomplete emptying Post-void dribbling Straining
FUNDHIPS: Frequency Urgency Nocturia Dysuria Hesitancy Incomplete voiding Poor stream Smell/odour
What are the symptoms of urinary retention?
Acute retention symptoms:
Sudden inability to pass urine
Severe pain
Chronic retention symptoms:
Painless
Frequency: with passage of small volumes of urine
Nocturia is a major feature
What are the signs on physical examination of benign prostatic hyperplasia?
DRE: the prostate is usually smoothly enlarged with a palpable midline groove
Poor correlation between the size and the severity of the symptoms
Signs of Acute Retention: Suprapubic pain and a distended, palpable bladder
Signs of Chronic Retention: A large distended painless bladder (volume > 1 L) and signs of renal failure.
What are the appropriate investigations for benign prostatic hyperplasia?
Urinalysis - look for signs of UTI (leukocytes, nitrites, blood)
PSA - may also be raised in prostate cancer and prostatitis
U+Es - check for impaired renal function
Volume charting to record frequency and volume of voiding
International Prostate Symptom Score - score from 0-35
Imaging:
USS - may show mass, urolithiasis or hydronephrosis
CT abdo/pelvis - may show mass, urolithiasis or hydronephrosis
Cystoscopy - may show mass, stone or stricture
Bladder scanning to measure pre- and post-voiding volumes
Transrectal ultrasound scan (TRUS): allows assessment of bladder size and volume
What is the management of benign prostatic hyperplasia?
Emergency acute urinary retention: catheterisation
Conservative if mild - watchful waiting, limitation of fluids, bladder training focused on timed and complete voiding
Medical:
Alpha-blocker eg terazosin, tamsulosin - relax smooth muscle in prostate and internal urinary sphincter (effective in days)
5-alpha-reductase inhibitor eg finasteride - decrease conversation of testosterone to DHT which reduces prostate volume (effective in months)
PDE5 inhibitors
Anticholinergic therapy
Surgery: TURP or open prostatectomy
What are the possible complications of benign prostate hyperplasia?
BPH progression UTI Renal insufficiency Bladder stones Haematuria Sexual dysfunction Acute urinary retention Overactive bladder
Complications of TURP
TURP syndrome: seizures or cardiovascular collapse caused by hypervolemia and hyponatraemia due to absorption of glycine irrigation fluid.
What is the prognosis of benign prostatic hyperplasia?
Mild symptoms are usually well controlled medically
Majority of patients require ongoing therapy
Most patients get significant relief from surgery
2.5% of patients will develop acute urinary retention and another 6% will require invasive therapy over a 5-year period
Define chronic kidney disease
Chronic renal failure characterised by the presence of kidney damage or decreased kidney function by a eGFR < 60 ml/min/1.73 m² and/or pathological abnormality of the kidney such as microalbuminuria, proteinuria, haematuria for three months or more.
Explain the aetiology of chronic kidney disease
Most common cause in adults is diabetes - 1/3 of diabetics will develop it
Second most common cause is hypertension
Less frequent causes:
Cystic disorders of the kidney (polycystic kidney disease)
Obstructive uropathy
Glomerular nephrotic and nephritic syndromes
What are the risk factors for chronic kidney disease?
Diabetes Hypertension Age >50 Childhood kidney disease Smoking Obesity Male Family history of CKD Autoimmune disease Long term NSAID use Black or hispanic ethnicity
Summarise the epidemiology of chronic kidney disease
Common - 11% of the adult population has CKD
Often not recognised until advanced
Incidence increasing
More common in Black and hispanic patients and those with family history
Those who have had previous AKI are at increased risk
What are the presenting symptoms of chronic kidney disease?
Often ASYMPTOMATIC and incidental finding of a routine blood or urine test.
Symptoms of Severe CKD: Swelling in peripheries and/or around eyes (due to oedema) Muscle cramps Orthopnoea and/or Dyspnoea (due to pulmonary oedema) Sexual dysfunction Fatigue Nausea and vomiting Pruritis Anorexia
What are the signs on physical examination of chronic kidney disease?
May show signs of underlying disease (e.g. SLE)
May show complications of CKD (e.g. anaemia)
Signs of CKD: Skin pigmentation Excoriation marks due to pruritis Pallor Hypertension Peripheral oedema Peripheral vascular disease Retinopathy
What are the appropriate investigations for chronic kidney disease?
Serum Creatinine – elevated > 97micromol/L
May be falsely low in conditions of low muscle mass, older or malnourished people and patients with liver failure
Serum Urea: Varies massively depending on hydration status and diet
Urinalysis: Haematuria and/or proteinuria
Serum or urine protein electrophoresis: check for multiple myeloma
Urine microalbumin: microalbuminuria (30-300 mg/day)
Renal ultrasound: Small kidney, presence of obstruction/hydronephrosis
Abdominal x-ray/CT/MRI
Estimation of GFR (more accurate than serum creatinine alone) - <60 mL/minute/1.73 m²
ISOTOPIC GFR: gold standard but expensive
Renal Biopsy Biochemistry
Glucose: check for undiagnosed diabetes and diabetic control
Potassium: raised
Serology:
Antibodies: ANA (SLE), c-ANCA (granulomatosis with polyangiitis – Wegener’s) and anti-GBM (Goodpasture’s syndrome)
Hepatitis serology
HIV serology
Define epididymitis
Inflammation of the epididymis characterised by unilateral scrotal pain and swelling of less than 6 weeks’ duration which may be associated with irritative lower urinary tract symptoms, urethral discharge, and fever.
Define orchitis
Inflammation of the testes.
60% of epididymitis is associated with orchitis
Most cases of orchitis are associated with epididymitis
Explain the aetiology of epididymitis and orchitis
Sexually active men:
Usually caused by sexually transmitted organisms
Chlamydia trachomatis
Neisseria gonorrhoeae
Mycoplasma genitalium
Insertive partner during anal intercourse may develop acute epididymitis from enteric E. coli organisms
Older men (>35 years):
Enteric causative pathogens
Associated with bladder outlet obstruction, recent instrumentation of the urinary tract, or systemic illness.
Enterobacter, Klebsiella
Rare: TB, syphilis
Viral: Mumps
Fungal: Candida if immunocompromised
What are the risk factors of epididymitis and orchitis?
Diabetes Vasculitis Unprotected sexual intercourse Bladder outflow obstruction - BPH, urethral stricture Instrumentation of urinary tract Mumps Exposure to TB Amiodarone
Summarise the epidemiology of epididymitis and orchitis
Most common cause of acute scrotal pain
Can present at any age but most patients are 20-39 years old
Majority of cases in children occur around puberty in early adolescence
What are the presenting symptoms of epididymitis and orchitis?
Unilateral scrotal pain and swelling of gradual onset Tender scrotum Hot, erythematous, swollen hemiscrotum Frequent and painful micturition Purulent urethral discharge
What are the signs on physical examination of epididymitis and orchitis?
Swollen and tender epididymis or testis
Scrotum may be erythematous and oedematous
Pyrexia
Walking will be painful
Eliciting a cremasteric reflex may be painful
What are the appropriate investigations for epididymitis and orchitis?
Gram stain of urethral secretions - ≥5 WBC per oil immersion field; presence of intracellular gram-negative diplococci
Urine dip for first-void MC&S - early morning urine sample - ≥10 WBC per high-power field
Nucleic acid amplification test/urethral secretions/first-void urine - test for C. trachomatis, N. gonnorrhoeae and mycoplasma genitalium
Bloods: FBC (elevated WCC), elevated CRP and U&Es Imaging: Increased blood flow on duplex examination
What is the management of epididymitis and orchitis?
Due to bacterial infection:
Antibiotics - ceftriaxone + doxycycline (+azithromycin if due to gonnorrhoea), ceftriaxone + a fluoroquinolone if due to enteric organism
Supportive measures - bed rest, analgesia, scrotum elevation, NSAIDs, advice to avoid unprotected sex
If due to TB - anti-tuberculosis antibiotics
Surgical: Exploration of testicles if testicular torsion cannot be excluded clinically. Required if an abscess develops.
What are the possible complications of epididymitis and orchitis?
Abscess formation
Testicular ischaemia/infarction
Epididymal obstruction
Chronic pain
Fournier’s gangrene (if the infection is left untreated and spreads)
Mumps orchitis could cause testicular atrophy and fertility issues
What is Fournier’s gangrene?
A life-threatening form of necrotizing fasciitis that affects the genital, perineal, or perianal regions of the body.
What is the prognosis of epididymitis and orchitis?
Symptoms usually resolve rapidly following antibiotic therapy
May take up to two months for the swelling to resolve
Inadequately treated infectious epididymitis, particularly sexually transmitted infection, can in rare cases lead to epididymal obstruction or testicular atrophy and subsequent infertility problems.
Define glomerulonephritis
An immunologically mediated inflammation of the renal glomeruli. This causes glomerular injury. Inflammatory changes are often in the glomerular capillaries and the glomerular basement membrane (GBM).
It presents with proteinuria, haematuria or both and can cause CKD or progress to kidney failure.
Explain the aetiology of glomerulonephritis
Many different types of glomerulonephritis with differing aetiologies
Some types are caused by the deposition of antigen-antibody complexes in the glomeruli. The antibodies which are produced are UKNOWN but may be associated with:
Bacteria - Streptococcus viridans, Staphylococci
Viruses - HBV, HCB, measles, mumps, EBV
Protozoal - Plasmodium malariae, schistosomiasis
Inflammatory/Systemic diseases - SLE, vasculitis, cryoglobulinaemia
Drugs - gold, penicillinamine
Tumour - lung cancer, colorectal cancer, leukaemia
What are the risk factors of glomerulonephritis?
Group A β-haemolytic Streptococcus Respiratory/GI infections Hep B/C Infective Endocarditis HIV SLE Lung/Colorectal Cancer Drugs Systemic vasculitis Leukaemia
