Urinary Tract Infections COPY Flashcards
What are lower UTIs
Cystitis, urethritis and prostatitis.
What are upper UTIs
Pyelonephritis, intra-renal abscess and perinephric abscess
What are uncomplicated UTIs
Infection in a structurally and neurologically normal urinary tract. Shorter duration
Whar are complicated UTIs
Infection in a urinary tract with functional or structural abnormalities (cystitis of long duration or haemorrhagic cystitis
What are some signs and symptoms of lower UTIs
Frequency, urgency, dysuria, suprapubic pain, haematuria, smelly or cloudy urine
What are signs are symptoms of infection of pelvic/kidneys
Loin pain and tenderness, high fever and systemically unwell
What are some of the predisposing factors for UTIs
- Obstruction eg, calculi, tumours, benign prostate hyperplasia.
- Viscoureteral reflux,
Incomplete bladder emptying, - Diabetes, sickle cell or immunosuppression,
- Bladder instrumentation/ foreign bodies,
- Congenital structural abnormalities,
- Sexual activity/pregnancy
What is significant about catheterisation?
Incremental risk of CAUTI associated with each additional day of catheterisation
What are some of the host defences for urinary tract infections
- Urine (osmolality and pH),
- Sloughing of epithelial cells,
- Urine flow and micturition,
- Mucosal inhibitors of bacterial adherence,
- Complement activation,
- Inflammatory response,
- Commensals
What are the most common causes of UTIs?
1) E.coli,
- Klebsiella
- Staphylococcus saprophyticus
- Candidia albicans,
- Trichomonas vaginalis,
- shistosoma haematobium
Describe how e.coli adheres to cells
Specific adhesion to uroepithelial cells via fimbirae
Describe the bacterial response to adhesion
Stimulates growth and reproduction and a biofilm may develop. Bacteria with type 1 fimbriae may become internalised by phagocytes.
Describe pathogenic factos of E.coli
K antigen - Forms a micro-capsule and confers resistance to phagocytosis.
Haemolysin - Damages tissue membranes in vivo causing kidney damage
Describe features of preoteus mirabilis
Gram neg bacillus with pertrichous flagellae. It produces urease which makes urine less acidic. Favouring colinisation of bacteria
Describe features of staphylococcus saprophyticus
Gram positive bacterial which is part of the normal microbiota of female perineum and vagina. Commonly causes community acquired UTIs and symptomatic cystitis
Describe some features of candida albicans
It is a fungus which is an opportunistic pathogen in immunocompromised individuals and is often associated with antibiotic use
Describe features of trichomonas vaginalis
Protozoan which prefers pH of 6. Less common in males
How can you diagnose UTIs?
- History taking (clinical signs and symptoms),
- Urine dipstick,
- Laboratory diagnosis
What two symptoms increase the probability by over 90% that the diagnosis is UTIs?
Frequency and dysuria
What are the main indications for urine culture?
- Children,
- Male UTI,
- Immunocompromised,
- Pregnancy,
- Toxic appearance,
- Underlying medical/urological disorder,
- Recently hospitalized,
- Recently hospitalized,
- recently instrumented,
- Recently on antibiotics,
- Recent treatment failure
What are some of the common oral antibiotics used for lower UTIs
Nitrofurantoin and trimethoprim (these 2 are most common) Ciprofloxacin, pivmecillinam and amoxicillin
What are some of the common oral antibiotics used for upper UTIs (pyelonephritis)
Co-trimoxazole, co-amoxiclav or ciprofloxacin
What are some of the possible complications of UTIs?
- Recurrent infections,
- Permanent kidney damage,
- Pyelonephritis,
- Low birth weight/premature infants,
- Urethral narrowing in men,
- Sepsis
