Surgical Aspects of Urinary Tract Infections

advertisement
The surgical significance of
urinary tract infections (UTIs) in
children
Marisa Seepersaud
MBBS MRCS DM
2011 (Sarah Amin)

Records were poor

22 patients , age 5 and under , who
were treated for UTI at the GPHC

Urinalysis: All
Urine culture: 4/22 (18%)


Abdominal ultrasound: 7/22 (32%)
(2 “enlarged kidneys”, 5 Normal
study)

2 referrals to urology1 PUV
Brandon Seepersaud
Urinary Tract Infection (UTI)

UTIs are among the most common bacterial
infections in children under 2 yrs old

The diagnosis is often missed on history and
physical examination
Recent Recommendations

AAP, American Academy of Pediatrics ,
(1999) 2013

Consensus Document, Management of UTI
in Jamaican Children, (2005), August 2011

NICE, National Institute for Health and
Care Excellence, UK (2007) May 2011
Incidence

~1% of children below age 1

~ 5 % of febrile children*, 2- 24 months of
age

7.5% girls, 10% uncircumcised males, 2.5% of
circumcised males who present with a fever under 2yrs
Clinical significance of UTI

Associated with life-threatening sepsis in
the newborn

Increased rates of renal scarring in young
children
hypertension
chronic kidney disease
 pregnancy induced hypertension
Urinary tract infections may occur as
a result of structural anomalies of the
urinary tract
The diagnosis of urinary tract infection in a
young child is an important marker for
urinary tract abnormalities
Mandates investigation
Important to accurately make the diagnosis
Under-diagnosing UTI may lead
to under-treatment, underinvestigation, and risks
permanent renal damage
Risk of renal scarring with recurrent UTI
Jodul U. The natural history of bacteriuria in childhood. Infect Dis Clin North Am.
1987;1(4):713–729
100%
80%
60%
40%
20%
0%
1
2
3
4
5
Important to accurately make the diagnosis
Over-diagnosing UTI may
result in the development of
resistant organisms, the use of
limited resources for unnecessary and expensive
investigations,
(uncomfortable/painful/ scary
for patient; distressing for the
parents)
Age group
Symptoms and signs
Most common
Infants younger than 3 months
Infants older
Preverbal
than 3 months,
and children
Verbal

Least common
Fever
Vomiting
Lethargy
Irritability
Poor feeding
Failure to
thrive
Fever
Abd pain
Vomiting
Poor feeding
Loin tenderness
Lethargy
Irritability
Haematuria
Malodorous
urine
Failure to thrive
Frequency
Dysuria
Dysfunctional
voiding
Sec enuresis
Abd pain
Loin tenderness
Fever
Malaise
Vomiting
Haematuria
Malorous urine
Cloudy urine
Who should be screened for a UTI?


Infants and children with symptoms and signs of UTI
Infants* with 1 or more of the following:
temperature of at least 38°C
fever for at least 2 days
absence of another obvious source of infection
Option

If the patient does not require immediate
antimicrobial treatment
 period of observation prior to investigation
and treatment for UTI
Dipstick screening of fresh urine
Both leukocyte esterase and nitrite
POSITIVE
UTI
Send urine for culture
May start antibiotics
Leukocyte esterase : negative
Nitrite : positive
Send urine for culture
Leukocyte esterase : positive
Nitrite : negative
Send urine for culture
Leukocyte esterase : negative
Nitrite : negative
UTI unlikely
Diagnosis

Must involve urine culture

Traditionally: >100,000 cfu/ml

Issues: contamination, false negatives, false
positives

Asymptomatic bacteriuria
Asymptomatic Bacteriuria (AS)
Colonization of the urinary tract with non-pathogenic organisms
Study of 3581 infants
 2.5% male infants, 0.9% female infants
 2 patients with AS developed symptomatic UTI soon after
 None of the other patients who developed UTI in the first year of life
were found to have AS at initial screening
Another study involving school aged girls with AS
 No difference in renal growth or function when patients were
randomised to treatment vs observation
 But the treated group appeared to be more likely to develop
pyleonephritis after antibiotics were stopped
Diagnosis of UTI:
2013 AAP recommendations

Presence of both >50 000cfu/ml of a single
organism/uropathogen AND

Pyuria

In an appropriately collected specimen

Febrile 2-24 month olds who have no obvious neurologic or anatomic
abnormalities known to be associated with rec UTI or renal damage (may be
extrapolated to under 5yr old)
Investigation of UTI: Culture

Urine collected in a bag
- only valid if NEGATIVE
- cannot be used to make a diagnosis of UTI
- positive culture is likely to be false positive (88%) !
- positive culture requires confirmation, which is impossible if
antibiotics were started*
REMEMBER: You want the most accurate test to be done initially since
urine may be rapidly sterilised
Appropriate methods

Catheter specimen urine (CSU)
 sensitivity: 95%
 specificity: 99%
 difficult in young girls*

Suprapubic Aspiration/ Bladder Tap (SPA)

MSU in older patients
Diagnosis

Urinalysis is Positive when:
Dipstick
nitrite
leukocyte esterase test
Microscopy
 white blood cells/pus cells
 +/- bacteria
The urinalysis may be negative
despite a positive culture:





Contamination
Asymptomatic bacteriuria
Urinalysis is not sensitive enough
Requires 4 hrs of “stasis” in the bladder
Young children, infants and neonates may void more often
Treatment

Initiating treatment orally or parenterally is equally
efficacious, so choice is based on practical considerations.

Choice of drug should be based on local sensitivity
patterns, adjusted according to sensitivity of particular
uropathogen

Duration of treatment: 7–14 days
EVERY CHILD, who has had a diagnosis of a
urinary tract infection, must be investigated for the
presence of a predisposing anatomic abnormality
of the urinary tract
Investigation

~5% of patients will be found to have some
abnormality on investigation

~16% of patients with febrile UTI

Overall about 1-2% of cases will be
determined to have “actionable” findings
which require some intervention.
Should patients be put on prophylaxis while
awaiting investigations?

YES

No
Parental education

Implications/complications of a UTI

Symptoms/signs of a recurrent UTI

Need for a urine culture for future febrile illnesses , even
when there is an apparent source of fever

Instructed to seek prompt medical evaluation for future
febrile illnesses to ensure that recurrent infections can be
detected and treated promptly
Imaging Investigations for UTI

Abdominal Ultrasound

MCUG/VCUG

Renal scan (DMSA)

Intravenous Pyelogram (IVP)
Investigation: KUB USS

All patients diagnosed with UTI should
undergo kidney/ureter/bladder sonography
(KUB USS)

Timing: 6weeks post treatment

Exception: if
patient is not responding to treatment as
expected, unusually ill  KUB USS within 48hrs
Micturating/Voiding cystourethrogram
(MCUG/VCUG)

MCUG is not recommended routinely after the first febrile
UTI if KUB USS is normal.
Schroeder AR, Abidari JM, Kirpekar R, et al. Impact of a more restrictive approach to urinary tract
imaging after febrile urinary tract infection. Arch Pediatr Adolesc Med. 2011;165(11):1027–1032

Recommended in the presence of
 an abnormal KUB USS
 recurrent UTI
 atypical UTI

MCUG done 4-6 weeks after the UTI
Look at the films , incl post micturation films

Renal Scan/ Radionucleotide Scan (RNC)
May be used in the acute setting to diagnose pyleonephritis
 Helpful in distinguishing between obstructive and nonobstructive causes of hydronephrosis
Provides information on differential function
 Indentify renal cortical defects (DMSA)
IVP is useful in the absence of the RNC
All patients with UTI’s should
have:
Urine culture
 Urinalysis
 Abdominal Ultrasound

+/- MCUG
 +/- Renal scan
 +/- IVP (in the absence of renal scan)

What about long term urinary prophylaxis
following UTI?

Urinary prophylaxis is dictated by the underlying
pathology

Antibiotic prophylaxis should not be recommended in
infants and children after the first UTI (if no underlying
abnormality was found )

May be considered in infants and children with recurrent
UTI
Dysfunctional elimination syndromes and
constipation should be addressed in
infants and children who have had a UTI.
Normal Cystogram (MCUG)
Normal Bladder and Urethra
Posterior urethral valves (PUV)
Posterior urethral valves
Bladder Diverticulum
Bladder diverticuli
Detrusor Instability
Grade I Vesicoureteric Reflux
(VUR)
Grade II Vesicoureteric Reflux
(VUR)
Grade IV Vesicoureteric Reflux
(VUR)
Contrary to previous beliefs

“VUR with UTI without structural abnormalities in the
kidneys seems not to cause CKD.”

“Active treatment of VUR seems not to reduce the
occurrence of CKD and, in large prospective follow-up
studies, the renal function of patients with VUR has been
well preserved.”
Salo J, Ikäheimo R, Tapiainen T, et al. Childhood urinary tract infections as a cause of
chronic kidney disease. Pediatrics. 2011;128(5):840–847
Recurrence of UTI in patients with VUR
prophylaxis vs observation
Prophylaxis
Reflux Grade
No
Prophylaxis
N
P
# of Recurrences /
Total N
# of Recurrences /
Total N
None
373
7 / 210
11 / 163
0.15
Grade I
72
2 / 37
2 / 35
1.00
Grade II
257
11 / 133
10 / 124
0.95
Grade III
285
31 / 140
40 / 145
0.29
Grade IV
104
16 / 55
21 / 49
0.14
Grade V Vesicoureteric Reflux
(VUR)
Recurrence rate of febrile UTI in ages 2-24 months
100%
80%
Prophylaxis
60%
No Prophylaxis
40%
20%
0%
None
Grade I
Grade II
Grade III
Grade IV
Normal Intravenous Pyelogram
(IVP)
Pelviureteric Junction (PUJ) Obstruction
Urolithiasis
Who should be referred to the paediatric nephrologist/
paediatric urologist/ paediatric surgeon?










Poor response to treatment of UTI/uncertainties of Mx
Recurrent UTI
Neurogenic bladder
Voiding dysfunction
Symptoms of dysfunctional elimination syndrome
Hydronephrosis (obstructive or non obstructive;
intrauterine or post natal)
Abnormal radiology (KUB USS, MCUG, Renal scan)
Suspicious looking radiology even if reported as normal
Renal scarring
Obstructive uropathy (antenatally or postnatally diagnosed)
Role of Circumcision

Presence of foreskin does not worsen UTI
or increase risk of UTI once there is proper
hygiene
Role of Circumcision
Circumcision has a limited role in treatment
of UTI:
1.
2.
Recurrent UTI with no other abnormality
Solitary hydronephrotic kidney
Summary: Diagnosis/Mx UTI





Diagnosis
–
Abnormal urinalysis as well as positive culture
–
Positive culture = ≥50,000 colony-forming units (cfu)/ml
Treatment - Oral as effective as parenteral
Imaging - KUB USS for all patients
- Voiding cystourethrography (VCUG) not recommended
routinely after first febrile UTI; required if KUB USS is
abnormal; necessary for recurrent and atypical UTI
Follow up – Emphasis on urine testing with subsequent febrile
illnesses
Referral – Early referral to paediatric surgery (paedi urology
/nephrology)
Thank You.
Download