How reliably can paediatric professionals identify pale stool from cholestatic newborns?
- 1King's College Hospital, London, UK
- 2Institute of Child Health, University College London, London, UK
- 3Greenwich Teaching PCT, London, UK
- 4Children's Liver Disease Foundation, Birmingham, UK
- 5University College London, London, UK
- Correspondence to Dr Alastair Baker, Consultant Paediatric Hepatologist, Paediatric Liver Unit, King's College Hospital, Denmark Hill, London SE5 9RS, UK;
- Accepted 31 May 2011
Background The success of surgery in infants with hepatobiliary disease is inversely proportional to the age when surgery was performed. Pale stool colour is a major indicator of biliary obstruction. However, simple recognition has been inadequate, resulting in late diagnosis and referral.
Objective To assess the skills of healthcare professionals in recognising pale stools.
Method Photographs of normal, acholic and indeterminate infant stools were shown to paediatric professionals who have regular contact with jaundiced babies at three London teaching hospitals. Each stool was classified as ‘healthy’ or ‘suspect’.
Results One-third of the stools were not correctly identified by physicians and nurses.
Conclusion Experienced professionals often do not recognise stool colour associated with biliary obstruction. The authors propose that stool colour cards similar to those used in Japan and Taiwan may improve early detection of hepatobiliary disease at a minimal cost.
Biliary atresia (BA) is a disease of unknown aetiology with an incidence of approximately 1 in 16 700 births. BA is the main surgical cause of neonatal cholestasis and the commonest reason for paediatric liver transplantation.1,–,3 It is characterised by inflammatory destruction of the normal fetal or neonatal hepatic biliary system, leading to biliary cirrhosis.1,–,6 Infants are generally well at presentation, so the condition may be overlooked.1,–,3 ,7 Early signs of BA are jaundice for longer than 2 weeks, pale stools and dark urine.2 ,3 Earlier surgery can achieve long-term survival as the success of the Kasai portoenterostomy is inversely proportional to the age at surgery.3,–,7 Later referral with complications of cirrhosis typically necessitates liver transplantation within 1 year.2 ,3 ,8 Although up to 15% of infants experience jaundice for longer than 14 days, only 0.2–0.4% of infants have a liver pathology.1 Pale stool colour is a major indicator of biliary obstruction. The objective of our study was to investigate the level of recognition of pale stools among healthcare professionals.
Following approval by the Royal Free and University College School of Medicine Ethics Committee, stools of normal infants and 12 cholestatic infants were collected from postnatal wards of two London teaching hospitals and from the King's College Hospital (KCH), a National Paediatric Hepatology Centre, respectively. Stool samples were photographed using Nikon D70 digital SLR camera with computer colour calibration for ambient light. Photographs of five normal, three indeterminate and four acholic stools confirmed by clinical diagnosis (figure 1) were shown to paediatric nurses and doctors at KCH; University Hospital Lewisham (UHL), a University General Hospital; and University College London Hospital (UCLH), a Regional Specialty Hospital. They were asked individually to classify each stool as either ‘suspect’ or ‘normal’, that is, compatible with a diagnosis of BA or not. The responses were assessed as either correct or incorrect. The questionnaire did not permit respondents to record ‘Don’t know' but answers could have been omitted.
Eighty-one questionnaires were completed by 36 paediatric doctors and 45 paediatric nurses across the three sites. The suspect stools were correctly identified in 62.8% of responses. The figure was similar for doctors (62.7%) and nurses (62.9%). Analysis of responses revealed that pale and indeterminate stools were correctly identified at KCH by 66.9% of respondents, for UCLH, 64.8% and UHL, 54.1%. There were no differences among the three institutions or between doctors and nurses in identifying a suspect stool. Among the staff, 37.2% failed to recognise a suspect stool.
The results suggest that the accuracy of clinical judgement to detect BA is independent of the institution and the professional background of the healthcare professional. This may well replicate the situation in primary care, with delay in referral of BA because pale stools are missed.4 Examining stool colour is considered the most sensitive and specific way to screen for BA. A pale stool is always pathological in early infancy and is generally considered easy to recognise.3 ,9 ,10 Stools of normal neonatal breastfed babies should be recognised as bright ‘daffodil’ yellow and of those bottle-fed as similar to English mustard in colour. A BA stool comes in many possible tones of ‘pale’, from cream cheese, to uncooked pastry, putty, pale yellow as represented by figure 2, or even pale brown similar to a pale manila envelope. Dark urine can colour a loose stool, making recognition harder.
It has been argued that education of parents and professionals for abnormal stool colour should permit earlier diagnosis of BA,4 ,11 ,12 but efforts have yielded disappointing results, even in well-organised primary healthcare services such as the UK. Currently, we are unable to discover any standard polices that exist within UK primary care or hospitals to ensure detection of pale stools in newborns.11
The need for and timing of screening for BA is unresolved. In its very early stages, features of BA may not have yet developed.13 Some authors contend that investigations should be deferred until 21 days to exclude a physiological cause of jaundice, as a false positive could lead to cessation of breast feeding.6 Others have suggested that screening by serum bile acids or urine bilirubin is preferable to promote early diagnosis, but lack of adequate sensitivity of tests and poor specificity with large numbers of false positives have defeated screening attempts so far.14
Moving the Well Baby Review from 6 weeks of age to 4 weeks to allow for earlier diagnosis has been suggested, but a 4-week baby review implemented in Japan failed to affect age at referral or surgery.14 A subsequent screening of over 17 000 infants in Japan using colour stool cards showing normal and abnormal stools increased the number of infants diagnosed with BA by 1 month of age.15 In Taiwan, a stool colour card proved to be effective with 95.2% sensitivity for pale stools.12
Children's Liver Disease Foundation (CLDF) produces a similar stool colour card in the UK (figure 3) that could be incorporated into an integrated care pathway for the management of BA from screening to treatment.16 ,17 Checking a baby's stool against the chart does not require substantial training and would take only moments.8 Costs of implementing colour stool cards would be limited to printing and distribution.18 We propose that mandating staff in contact with babies up to 8 weeks old to carry CLDF stool colour cards and refer those with jaundice and suspect stool directly to a paediatric liver service will improve outcomes of infants with BA.
The authors would like to thank Professor Davenport for providing the picture of a pale stool (figure 3). The authors would also like to thank CLDF for supplying stool colour charts and Dr Jane Hawdon, Consultant Neonatologist, UCLH, for her assistance. AGS is Reader in Child Health (Honorary Consultant).
Competing interests None.
Ethics approval This study was conducted with the approval of The Royal Free and University College School of Medicine Ethics Committee.
Provenance and peer review Not commissioned; externally peer reviewed.