Early detection of biliary atresia: past, present & future

The composition of the gut microbiota is altered in biliary atresia with cholangitis

Aim

To detect the composition of the gut microbiota in biliary atresia after Kasai surgery.

Methods

Infants within six months after the Kasai operation who were diagnosed by cholangiography at Shanghai Children’s Hospital were enrolled in the study. Fecal samples were collected from diapers, placed into sterile tubes in the inpatient department or outpatient department and frozen at −80°C within half an hour. The gut microbiota was detected by 16S rRNA sequences. Then, the patients that were followed up to one year after the Kasai operation who suffered from cholangitis at least one time were grouped into the BAcho group, and the others were grouped into the BAnoncho group.

Results

Nine of 18 BA patients were grouped into the BAcho group, and the others were grouped into the BAnoncho group. In the BAcho group, AST, ALT and GGT were significantly increased compared to the BAnoncho group. The number of total OTUs (operational taxonomic units) in feces was more elevated in the BAnoncho group than in the BAcho group. In the BAnoncho group, the Chao index at the OTU level was significantly increased compared to that in the BAcho group (66.37 ± 21.5 vs. 45.64 ± 11.25, p = 0.02 < 0.05). Bifidobacterium was the most abundant genus in the BAnoncho group, accounting for 22.14%, and Klebsiella accounted for 22.74% in the BAcho group. Compared with the BAnoncho group, Bacteroides was significantly decreased in the BAcho group (p = 0.037).

Conclusion

The composition of the gut microbiota was different between BA with cholangitis and BA without cholangitis.

Screening for biliary atresia

Early diagnosis followed by proper KP is essential for the improvement of long-term prognosis for patients with BA. It is increasingly accepted that KP at ≤ 30 days of age significantly improves native liver survival rate. Published analyses in English and Japanese indicate that screening by SCC and DB/CB is potentially feasible. Screening with SCC has been implemented in Tochigi Prefecture, Japan, since 1994. The concept of SCC was introduced from Japan to Taiwan and resulted in nationwide screening with SCC for the first time in Taiwan in 2004, followed by Japan in 2012. Home-based screening using SCC is easy and cost-effective; however, it may cause some difficulties for families in case of stools with intermediate colors. Laboratory-based screening using DB/CB may detect the suspected cases earlier, resulting in an increase in the number of patients with BA who undergo KP at ≤ 30 days of age; however, the recall rate is 1% and may be beyond an acceptable range. Further studies are needed to assess the feasibility and cost-effectiveness of both home-based (SCC) and laboratory-based (DB/CB) screening for BA.

Conjugated hyperbilirubinemia presenting in first fourteen days in term neonates

AIM

To describe the etiology and characteristics of early-onset conjugated hyperbilirubinemia (ECHB) presenting within 14 d of life in term neonates.

METHODS

Retrospective review was performed of term infants up to 28-d-old who presented with conjugated hyperbilirubinemia (CHB) at a tertiary center over a 5-year period from January 2010 to December 2014. CHB is defined as conjugated bilirubin (CB) fraction greater than 15% of total bilirubin and CB greater or equal to 25 μmol/L. ECHB is defined as CHB detected within 14 d of life. “Late-onset” CHB (LCHB) is detected at 15-28 d of life and served as the comparison group.

RESULTS

Total of 117 patients were recruited: 65 had ECHB, 52 had LCHB. Neonates with ECHB were more likely to be clinically unwell (80.0% vs 42.3%, P < 0.001) and associated with non-hepatic causes (73.8% vs 44.2%, P = 0.001) compared to LCHB. Multifactorial liver injury (75.0%) and sepsis (17.3%) were the most common causes of ECHB in clinically unwell infants, majority (87.5%) had resolution of CHB with no progression to chronic liver disease. Inborn errors of metabolism were rare (5.8%) but associated with high mortality (100%) in our series. In the subgroup of clinically well infants (n = 13) with ECHB, biliary atresia (BA) was the most common diagnosis (61.5%), all presented initially with normal stools and decline in total bilirubin but with persistent CHB.

CONCLUSION

Secondary hepatic injury is the most common reason for ECHB. BA presents with ECHB in well infants without classical symptoms of pale stools and deep jaundice.

Recent advances in the pathogenesis and management of biliary atresia

PURPOSE OF REVIEW

The purpose of this study is to review advances in both the pathogenesis and clinical management of biliary atresia.

RECENT FINDINGS

Immunologic studies have further characterized roles of helper T-cells, B-cells, and natural killer cells in the immune dysregulation following viral replication within and damage of biliary epithelium. Prominin-1-expressing portal fibroblasts may play an integral role in the biliary fibrosis associated with biliary atresia. A number of genetic polymorphisms have been characterized as leading to susceptibility for biliary atresia. Postoperative corticosteroid therapy is not associated with greater transplant-free survival. Newborn screening may improve outcomes of infants with biliary atresia and may also provide a long-term cost benefit.

SUMMARY

Although recent advances have enhanced our understanding of pathogenesis and clinical management, biliary atresia remains a significant challenge requiring further investigation.

Cost-effective analysis of screening for biliary atresia with the stool color card

BACKGROUND

Biliary atresia (BA) is the leading cause of pediatric end-stage liver disease and liver transplantation in the United States. Early diagnosis leads to improved outcomes, but diagnosis is often delayed, leading to increased rates of transplantation and mortality.

METHODS

A Markov model was developed to simulate the natural history and transplant-related outcomes of patients with BA in a US cohort studied for 20 years. Data regarding proportions of individuals in different health states, including transplant and death, were obtained from published literature. Costs were derived from the literature and the Johns Hopkins database of charges using the cost-to-charge ratio. Strategy A represented the status quo and assumed no screening. Strategy B used nationwide screening with the stool color card developed by the Taiwan Health Bureau. The cost associated with both strategies was compared with the number of life-years gained, deaths, and the number of transplants for a 20-year interval. A dominant strategy was one that was associated with lower cost alongside improved outcomes, including increases in life-years gained, reductions in number of deaths, and reductions in number of transplants. One-way and probabilistic sensitivity analyses were performed.

RESULTS

In strategy A, the 20-year cost was $142,479,725 with 3702 life-years, 74 deaths and 158 liver transplants. For strategy B, the cost was $133,893,563 with 3731.7 life-years, 71 deaths and 147 liver transplants. There was a >97% probability that screening with the stool color card would be cost saving and associated with an increase in life-years gained. Among all parameters, only stool color card specificity was associated with the potential for screening to no longer be cost saving.

CONCLUSIONS

Compared with no screening, screening with the stool color card is a dominant strategy associated with lower costs and better outcomes. These findings suggest that screening with the stool color card could be an important, economically feasible strategy for improving outcomes in BA in the United States.

Differentiating Biliary Atresia from Other Causes of Cholestatic Jaundice

Diagnosis of biliary atresia (BA) in infants presenting with cholestatic jaundice (CJ) requires exploratory surgery with cholangiography. However, the lack of a standardized approach to pre-operative evaluation of infants with CJ can lead to a high number of negative surgical explorations. We reviewed our experience with CJ and BA to determine preoperative variables that might reliably identify BA. Infants explored for possible BA over a 5–year period were retrospectively reviewed. Preoperative clinical indices and liver biopsy results were reviewed. Statistical analysis was conducted by Student's t test and Fisher's exact test ( P < 0.05). Twenty patients were identified, 10 with BA and 10 without (50% negative exploration rate). Nuclear cholescintigraphy (HIDA) excretion into the gastrointestinal tract was absent in all BA and in 8 of 10 without BA. Hepatomegaly was more common in the BA group (OR = 9.3, P = 0.07). BA had higher mean (6 standard error) serum gammaglutamyl transpeptidase levels (542 ± 130 vs 139 ± 25.8 U/L in non-BA, P = 0.03). There were insignificant differences in sex, type of feeding, TPN exposure and sepsis between the two groups. Although our small sample size limits conclusions, we suggest screening infants with CJ by measuring GGT levels, absence of hepatomegaly, presence of cholic stools and/or excretion on HIDA scan to undergo pecutaneous liver biopsy given the lower likelihood of BA necessary.

Diagnosis of Biliary Atresia Can not be Excluded by Declining Trend of Serum Direct Bilirubin

The aim of this paper is to investigate the clinical courses of patients with biliary atresia (BA) during neonatal period. We examined 19 patients with BA, who underwent blood tests including direct bilirubin (D-Bil) within 20 days of age, in 3 tertiary hospitals in Japan. The first blood sample was collected at 8.4±6.5 days of age. The acholic stool was observed within 2 weeks of age in 16 cases (84.2%). Decrease of T-Bil was observed in all the subjects, with a range of reduction of 6.5±3.3 mg/dL, from 10.4±7.5 to 29.8±9.1 days of age. Decrease of D-Bil was also observed in 17 out of 19 cases (89%), with a range of reduction of 1.1±1.0 mg/dL, from 15.5±8.0 to 24.9±9.6 days of age. A significant decrease of D-Bil was observed in 2 cases of biliary atresia splenic malformation syndrome. We therefore conclude that clinicians treating icteric infants should not exclude a diagnosis of BA even if the level of D-Bil has a declining tendency.