URIANRY TRACT INFECTIONS Flashcards
UTI can progess to the following infections
Pyelonephritis
Urosepsis
Why do neonates present with nonspecific symtoms in UTI
UTIs in neonates are due to hematogenous rather than ascending infection
Where does UTI generally begin from after the neonatal period
The bladder with ascending disease to the kidneys
Bacterial invasion of the bladder with overt UTI symptoms is more likely to occur if……….
Urinary stasis or low flow conditions exist
Effect of circumcision on UTI
Uncircumcised males> Circumcised males
UTI prevalence in different sexes
Neonates: males>females
Above neonatal period: females>males
Risk factors for UTI
Bacterial virulence
Host factors
factors in bacteria that increases their virulence in UTIs
Antigen K
Presence of fimbriae
Host factors that predispose to UTI
Anatomical
Functional
Immunologic
Causes of UT obstruction
Phimosis
Meatal stenosis
Posterior urethral valve disorder
Diverticuli
Ureteric stricture or kink
Claculi
Anatomical host risk factors of UTI
Vesicoureteral reflux
Abnormal insertion of ureters in the bladder
UT obstruction
Indwelling catheter
Meatal stenosis
Narrowing of the opening at the end of the penis (the external urethral opening or meatus)
Phimosis
A condition in which tight foreskin cannot be pulled back over the head of the penis
Posteriori urethral valve
Obstructive valves that develop in the urethra close to the bladder, obstructing urine outflow
Symptoms of UTI in neonates
Jaundice
Hypothermia or Fever
Failure to thrive
Poor feeding
Vomiting
Functional host risk factors of UTI
Neurogenic bladder in spina bifida
Inappropriate detrusor muscle contractions
Symptoms of UTI in infants
Poor feeding
Fever
Vomiting
Diarrhoea
Strong-smelling urine
Symptoms of UTI in preschoolers
Vomiting
Diarrhoea
Abdominal pain
Fever
Strong-smelling urine
Enuresis
Dysuria
Urgency
Frequency
Difference between UTI symptoms in preschoolers and school age children
Preschoolers - diarrhoea
School age children- flank pain
Symptoms of UTI in school age children
Fever
Vomiting
Abdominal pain
Strong-smelling urine
Dysuria
Frequency
Urgency
Flank pain
New enuresis
Hypertension in UTI raises suspicion of…..
Hydronephrosis
Renal parenchyma disease
Most common cause of UTI
E. coli
Causative agents of UTI
(FASKEEP)
Fungi in immucompromised patients
Adenovirus
S. aureus
Klebsiella spp
Enterocossus spp
E. coli
Proteus spp
Differentials of UTI
Sepsis
Falciparum malaria
GIT disorders
Renal calculi
Urethritis
Vaginitis
Vulvovaginitis
Physical examination in UTI
Costovertebral angle tenderness
Abdominal tenderness or mass
Palpable bladder
Examine external genitalia
Dribbling, poor stream or straining to void
Urinalysis diagnosis of UTI
Urine positive for nitrite, leukocyte esterase or blood
Which investigations can urine bag specimen be used for
Specific gravity
Chemical parameters
Not for culture
Microscopic examination of urine in UTI shows:
Presence of WBC(>5 per high-power field)
RBC
Bacteria
Casts
Epithelial cells
When is bag specimen used for UTI investigations in neonates and infants
If the urine bag is removed immediately after urine is collected
Urine sample collection in UTI
Midstream in adults
Bladder puncture in neonates and infants
Classic criteria for UTI
A clean-catch urine sample with more than 100,000 CFU of a single organism
If the specific gravity of the urine was low, 60,000-80,000 CFU may be significant.
When is lower colony counts significant
If present on a repeat culture
Why is urine collected in bags not suitable for culture
Due to high incidence of contamination
How to obtain better results from bag specimen
- Clean and dry perieum before placing bag
- Remove collected urine as soon as patient voids
Which level of CFU from bladder catheterization is considered significant for UTI
10,000 pure CFU/ml
Which level of CFU from suprapubic aspiration is considered significant for UTI
> 1000 CFU/ml
Increased BUN in a child older than 2 months raises suspicion for
Hydronephrosis
Renal parenchyma disease
Imaging studies in UTI
- Renal ultrasound
- Voiding cystourethrogram (VCUG)
Role of renal ultrasound in UTI
Depicts Kidney size and shape
limits of renal ultrasound
Poorly depicts ureters
No information on function
Role of VCUG
- Depicts Urethral and bladder antomy
- Detects vesicoureteral reflux (VUR)
Standard criterion for urine sample collection in UTI investigations
Suprapubic tap
Most invasive diagnostic procedure in UTI invetsigations
Suprapubic tap
Diagnostic procedure for patients who cannot provide a midstream clean-catch urine sample
Catheterization of the bladder
Suprapubic bladder aspiration
When is a urologist consulted at patient presentation
Evidence of urinary tract obstruction
When is short course therapy used
Adolescent females with evidence of cystitis
Recommended duration of antibiotic treatment in UTI
10 days
Why is short course therapy not used on children
It is more difficult to differentiate between cystitis and pyelonephritis`
Which route of antibiotics is used for febrile UTI in young infants and children according to recent evidence and why
Oral antibiotics
Because Short term(fever) and long term (pyelonephritis) outcomes are comparable to parenteral therapy
Which UTI patients require aggressive management in ER
Septic or toxemic patients
Route of antibiotics for cystitis and pyelonephritis
Cystitis- oral
Pyelonephritis- parenteral
Cystitis vs pyelonephritis
Cystitis: infection of bladder and urethra
Pyelonephritis: Infection of kidney
Antibiotics used in UTI
5C-GAN
Cefotaxime
Cephalexin
Cefixime
Ciprofloxacin
Co-trimoxazole
Gentamicin
Amoxicillin
Nalidixic acid
Amoxicillin dose
Paediatrics: IV/IM 100-200mg/kg/day divided q6hrs
Amoxicillin is usually combined with……
Gentamicin or Cefotaxime
Gentamicin dose
<5yrs: 2.5mg/kg/dose IV/IM q8hrs
> 5yrs: 1.5-2.5mg/kg/dose IV/IM q8hrs
Which antibiotic used as initial therapy for paediatrics with acute pyelonephritis?
Cefotaxime
Which antibiotic is used for neonates or jaundiced patients?
Cefotaxime
Cefotaxime dose
Paediatrics: 100-200 mg/kg/day in divided doses q6-8hrs
Spectrum of Co-trimoxazole
Common UTI pathogens ecxept P. aeruginosa
Dose for co-trimoxazole
> 2months: 5-10 mg/kg/day PO divided q12hours, based on TMP content
Dose for Cephalexin
Paediatric: 25-50mg/kg/dose PO q6h, max-3g/day
Dose for cefixime
Paediatric: 8mg/kg/dose PO qd: max:400mg/day
Oral antibiotics
used in UTI in paediatrics
Cephalexin
Cefixime
Co-trimoxazole
Parenteral antibiotics used in UTI in paediatrics
Ampicillin
Cefotaxime
Gentamicin
Contraindications to nalidixic acid
G6PD, causes hemolysis
Why is nalidixic acid used in UTI
it has minimal distribution in
tissues and is excreted mainly through the kidneys and
reach high concentration in urine
When is ciprofolxacin used
Second line or for recurrent UTI
Most common complication of UTI
Dehydration
Long term complications of UTI
Renal parenchyma scarring
Hypertension
Decreased renal function
Renal failure
