Pyelonephritis Flashcards
What are the symptoms of a urinary tract infection?
Cystitis (bladder infection) - dysuria - frequency - urgency - suprapubic pain - haematuria Pyelonephritis (infection of the kidney) - fever (>38) - chills/rigor - flank pain - costo-vertebral angle tenderness - nausea and vomiting
What are the risk factors for a UTI?
Infancy (under 1 year) Abnormal urinary tract (congenital/acquired) Females - anatomy - sexual intercourse - pregnancy Bladder dysfunction/incomplete emptying - constipation - neurogenic bladder - prostate enlargement Diabetes - glycosuria promotes bacterial growth Renal transplant Immunosuppression
Why are UTIs in childhood relevant?
More likely to indicate a structural abnormality
- congenital renal tract abnormality in up to 50% (vesico-ureteric reflux)
Can reduce risk of further damage
- renal scarring (irreversible)
- chronic kidney disease
- risk of hypertension increases with burden of scarring
What are the differential symptoms of an upper and lower tract UTI in children?
Upper tract - lethargy - general malaise - vomiting - loin pain - fever Lower tract - non specific abdominal pain - urgency - frequency - bed wetting - frank haematuria
What clinical signs indicate a UTI might be acute pyelonephritis or an upper urinary tract infection?
Bacteriuria and fever with a temperature of 38 or above
Bacteriuria, loin pain/tenderness and fever of less than 38
What clinical signs indicate a UTI might be cystitis or a lower urinary tract infection?
Bacteruria and signs and symptoms of UTI that aren’t systemic
How are UTIs diagnosed?
Multistix (leucocyte esterase and nitrite)
- useful in children >3 years
- positive for LE and nitrate indicates UTI
Microscopy and flow cytometry
- used when urine dipstick test is negative
- flow cytometry positive for pus cells and bacteria indicates a UTI
Urine culture
When are urine cultures done, and what would they show in a UTI?
Done in all children <3 years if there is clinical suspicion
- before antibiotics
Shows growth of a single organism
- be aware of contamination risk
How are UTIs managed?
Identification - test urine Antibiotic treatment - best guess while awaiting cultures - oral unless severely ill, vomiting or <3 months
What is the antibiotic treatment for a UTI?
Oral - trimethroprim - cephalosporin - co-amoxiclav - nitrofurantoin IV - 3rd gen cephalosporin (ceftriaxone) - gentamicin
What antibiotics can be used as prophylaxis in children with vesicoureteral reflux?
Nitrofurantoin
Trimethoprim
Co-amoxiclav
What are the pros and cons of US use in UTIs?
Pros
- radiation free
- readily available
- good for dilated drainage tracts and cysts
Cons
- operator dependent
- less sensitive for scarring and parenchymal change
What are the pros and cons of MCUG in diagnosing the cause of UTIs?
Pros - gold standard for VUR and PUV Cons - radiation - invasive (UTI risk)
What are the pros and cons of DMSA in diagnosing the cause of UTIs?
Pros - gold star for scars (decreased isoptope uptake) - differential function Cons - timing (acute or chronic) - differentiating a scar from dysplasia - radiation
What are the pros and cons of an MAG3 indirect cystogram in diagnosing the cause of UTIs?
Pros
- used for VUR study with no catheter needed
- differential function
Cons
- need continence and co-operation on bladder emptying
- no PUV information
- misses low grade VUR
What are the pros and cons of an MAG3 diuresis renogram in diagnosing the cause of UTIs?
Pros - gold standard for obstruction Cons - furosemide also needed to standardise the technique - operator interpretation
What are the risk factors for renal scarring?
Age High grade VUR Anatomical obstruction Dysfunctional voiding Frequent episodes of APN Therapeutic delay Bacterial virulence factors Host response Low birth weight Prenatal dysplasia
What are the most common congenital abnormalities of the kidney and urinary tract?
Vesico-ureteric reflux (VUR)
- retrograde passage of urine from the bladder into the upper urinary tract
Obstruction of the urinary drainage tracts
What can US pick up antenatally?
Dilated drainage tracts
Renal parenchyma (bright kidneys)
Oligohydramnios (not enough amniotic fluid surrounding the baby - fluid is feotus urine)
What is an MCUG?
Micturating cysto-urethrogram
- catheterisation in order to fill the bladder with a radiocontrast agent
- dye is watched under fluroscopy
- in VUR, the dye moves back up into the ureters and renal pelvi-calyceal systems
Describe VUR.
Presents
- in utero as hydro-uretero-nephrosis
- postnatally as UTIs and pyelonephritis
Can cause renal scarring (most dysplasia done prenatally)
Can be low or high grade
- low grade very likely to spontaneously resolve
How is VUR and a UTI managed?
Medical
- antibiotic propylaxis for high grade VUR until they are toilet trained
Surgical
- when medical management fails (recurrent, febrile UTI or new scarring)
- STING procedure
- open ureteric re-implantation
At what levels can there be obstruction in the urinary tract?
Pelvis/ureter Ureter Ureter/bladder Bladder Urethra
How can there be an obstruction within the bladder?
Posterior urethral valve - common congential cause among male infants Prostatic hypertrophy Function obstruction (neurogenic) - spina bifida - transverse myelitis - trauma (prune belly syndrome - congenital absence of abdominal muscles)
What is a posterior urethral valve?
An obstructing membrane in the posterior urethra
- valve leaflets of circumferential diaphragm
What is the presentation of posterior urethral valve?
Antenatal hydronephrosis
Urinary tract infection
Poor urinary stream
Renal dysfunction - if missed for a long time
How is a PUV managed?
Valve resection
Antibiotic prophylaxis
Chronic kidney disease care
How do pelvi-ureteric junction obstruction present?
Abdominal mass
Pain
Haematuria
UTI
How do vesico-ureteric junction obstructions present?
Anatomical narrowing vs functional obstruction Antenatal dilation UTI Abdominal mass Pain Haematuria
How are ureteric obstructions managed?
PUJO - observant (USS and DMSA) - pyeloplasty VUJO - observant (most resolve) - surgery for symptoms or due to increasing dilation) - resection and re-implantation
