Louisa Hemington ST5 General Paediatrics Oct 2015 Does prompt treatment of UTI in preschool children prevent renal scarring?

Louisa Hemington

ST5 General Paediatrics

Oct 2015

Does prompt treatment of UTI in preschool children prevent renal scarring?

Aim• To determine whether prompt active management of

UTI’s by primary and secondary care providers can reduce renal scarring rates.

Objective• Assess validity and reliability of a relevant paper• Ponder whether local practice needs to change

Paper Does prompt treatment of urinary tract infection in preschool children prevent renal scarring: mixed

retrospective and prospective audits.

Malcolm G Coulthard, Heather J Lambert, Susan J Vernon, Elizabeth W Hunter, Michael J Keir, John N S Matthews

Arch Dis Child 2014;99:4 342-347

Current practice• Management of UTIs is likely to be variable across

primary/secondary care despite NICE guidance• Our local guideline states that

– Decision to treat with antibiotics is based on a combination of clinical features together with a significant growth of bacteria in the urine

• Most childen that present with temperature have a urine sample

• In practice, UTIs are often ‘missed’ and patients called back and treated several days or even weeks after initial presentation

Methods 1• Compared two cohorts

– 1990’s group (retrospective)• All children <16y in Newcastle between 1992-1995• With first diagnosis of UTI• Imaged as per the 1991 recommendations

– 2000’s group (prospective)• Audited the impact of a PCT adopted ‘direct access’ (DA)

service for UTI Mx which was implemented in Newcastle on a cohort of children born after 1/1/04 with UTI

• Imaged as per 1991 recommendations (only difference children >3.5y had MAG3 in place of MCUG)

• Didn’t follow NICE guideline until study complete

Methods 2• ‘Direct Access’ service

– DA service nurse– Encouraged GPs to start antibiotic treatment on clinical

suspicion of a UTI immediately after urine collected , and then stop in culture negative cases rather than refer all cases to hospital

– Urgent microscopy advocated– Counsel parents of children with VUR to seek early medical

attention/urine microscopy– Offer trimethoprim prophylaxis– Imaged children as per 1991 guidelines– If UTI recurrence occurs repeat DMSA scanning

Outcome measures• 1990 group

– Focal DMSA defects consistent with scarring– Time to treat

• 2000 group– Focal DMSA defects consistent with scarring– Attendance interval (Sx onset - GP attendance)– Prescription interval (attendance – prescription) in days– Total: Symptom – Prescription time ‘Time to treat’

Results• Similar numbers of girls and boys referred with UTI in

1990 group and 2000 group – girls 8.7% v 10.6% – boys 3% v 3.1%

• Mean no of children– 1990s – 9376/year group for 4 years– 2000s – 4426/year group with decreasing FU

• Number imaged– 1990s – 2262 imaged– 2000s - 1664 imaged

Malcolm G Coulthard et al. Arch Dis Child 2014;99:342-347

Copyright © BMJ Publishing Group Ltd & Royal College of Paediatrics and Child Health. All rights reserved.

Cumulative referral rates of girls and boys with a urinary tract infection (UTI) in Newcastle, using a conventional UTI management model up to the age of 16 years during 1990s (open circles), and using the direct access model up to the age of 8 years during the 2000s (filled

circles).



Children were referred younger in the DA access group 2000s

Percentage rates for focal scarring (black bars) and isolated vesicoureteric reflux (grey bars) among girls and boys in Newcastle after a urinary tract infection.



GirlsOR of having a scar in DA group 0.47 (CI 0.29-0.76)

BoysOR of having a scar in DA group 0.35 (CI 0.16-0.81)

Less than half as likely to sustain a scar in the direct access group (2004-2012)



Symptom - treatment interval was longer for patients with scars OR 2.7 (CI 1.33-5.56)

Children treated within 3 days of their symptoms starting had less than half the chance of being scarred OR 0.37 (CI 0.18-0.75)

VUR• More isolated VUR in 2000 group

– Age adjusted OR 11.9 (CI 4.3 - 33.5) girls– OR 14.4 (CI 4.3 – 47.6) boys

• 1990s– 3 infants with isolated VUR (no scarring)

• 2000s– 103 children with isolated VUR

CASP checklists• Are the results of the study valid?

– Dealt with a clearly focused issue – sought to prove that by treating UTI early, scars can be prevented

– Clear outcomes defined of ‘renal scarring’ and ‘time to treat’

– 2 populations – one retrospective, one prospective

• 1990s: Population of of 154,000 <16y olds over 4yrs 1992-95 in Newcastle & adjacent districts

• 2000s: Population of 70,800 born after 1/1/04 managed by GPs/walk in centres/ED until 2012 (8 years)

– Populations covered different catchment areas of Newcastle

• Was the cohort recruited in an acceptable way?

• Yes

• Included all referred cases of UTI in the retrospective and prospective group

• Difference in age of children between the groups– 1990’s <16y– 2000’s Only studied 1-8yr olds

• Was the exposure accurately measured to minimise bias?

• Definition of UTI in both groups– Pure growth ≥105/mL E coli, Proteus, Klebsiella, Pseudomonas

or Enterococcus spp.

• Urine collection– 1990’s: no mention of how urine collected – 2000’s: family friendly urine pads for babies and washed up

potties for toddlers

• How the authors identified all the important confounding factors?– Analysed boys and girls separately– Only used ≤8yrs data from 1990 group for comparison– But 2 groups not matched in time or place

• Have they taken account of all the confounding factors in the design and/or analysis? – In 2000s group they adjusted for the attendance interval

• Was the outcome accurately measured to minimise bias?

• Yes• Standardised DMSA scan

• Was the follow-up of subjects – complete enough?

• Uncertain what proportion of referred patients in the 1990s group were scanned

• 1664/2069 had an USS and DMSA scan in the DA group

– long enough?

In the 2000 group the follow-up length decreased as the study progressed with the children presenting in 2004 having 8 years FU but those presenting in 2011 only having 1 yr

• What are the results?

• Children with a first UTI in the 2000s compared to those in the 1990s, – were referred younger, – were half as likely to have a renal scar (girls OR 0.47, 95% CI 0.29 to

0.76; boys 0.35, 0.16 to 0.81), – and were about 12 times more likely to have VUR without scarring (girls

11.9, 4.3 to 33.5; boys 14.4, 4.3 to 47.6).

• Children treated within 3 days of their symptoms starting were about 1/3 as likely to scar as those whose symptoms lasted longer – OR 0.33 (CI 0.12-0.72)

• How precise are the results?

• Reasonable confidence intervals

• Do you believe the results?

• Yes

• Can the results be applied to the local population?

• Comparable population to Sheffield• Difficult to implement locally without resources for a

similar DA service

• Do the results of this study fit with other available?

• One study that concluded that prompt treatment makes no difference only looked at children with pyelonephritis and acute DMSA scan changes

• Lots of studies about prophylaxis – remain inconclusive

• What the implications of this study for practice?

• Does raise awareness/add weight to the need for promptly treating UTIs

Summary & Conclusion

• Clinical bottom line– Prompt treatment of UTI (within 3 days) in children has the

potential to more than halve the scarring rate

Thanks for listening!

Documents

Louisa Hemington ST5 General Paediatrics Oct 2015 Does prompt treatment of UTI in preschool children prevent renal scarring?