Tag Archives: cholestasis

Foil PNALD with FOLE?

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As noted on previous blog entries (see below), there has been significant enthusiasm for fish oil based lipid emulsion (FOLE) despite a lack of data showing superiority compared with standard soy-based lipid emulsions at similar dosing.  More data for FOLE helping infants with cholestasis are available (J Pediatr 2013; 162: 793-8).

Design: Single center, prospective observational study of 57 infants with parenteral nutrition-associated liver disease (PNALD) which  took place between 2007-2011.  All infants were between 2 weeks and 6 months of age at enrollment.  At enrollment, FOLE (Omegaven) at a dose of 1 g/kg/d was infused over 24 hrs.  FOLE which is not FDA-approved is available on a compassionate use protocol.

Infant characteristics: Median gestational age: 28 weeks. 47 of 57 were long-term survivors.  The median time at initiation of FOLE was 39.3 weeks post-menstrual age.

Results:

  • Median conjugated bilirubin at initiation of FOLE therapy was 7.5 mg/dL.
  • Resolution of cholestasis occurred at a median of 35 days (range 7-129) after starting FOLE.  Longer times for resolution were noted in those with higher initial bilirubin.
  • Time to resolution was inversely proportional to gestational age at birth (p=0.02) and directly to time to receive 100% calories enterally (p=0.03)

The authors note that none of the infants who died had liver failure; most deaths were due to multi-organ failure and sepsis.

In the discussion, the authors state “the most significant finding from this study is the effectiveness of FOLE in resolving cholestasis irrespective of the initial serum bilirubin values.”  I take issue with this statement primarily because the design of the study does not allow such attribution.  Without a randomized trial comparing FOLE to standard intralipids, this statement overstates any conclusion that can be drawn from this study.  Given the fact that resolution was correlated with advancement of enteral feedings, it is plausible that a similar result would occur with standard intralipids.

The authors make a number of other speculations about the potential superiority of FOLE over standard soy-based lipid emulsions, but concede that “our study was not adequately equipped to address” the association of reduced intralipid with improvement in cholestasis.  Despite this concession, the authors boldly proclaim in the concluding paragraph: “while awaiting the more general availability of FOLE, infants at high risk should be identified early and referred to centers that provide the option of FOLE…in which families are fully informed of both the potential benefits and limited current data.”

A recent media report also promotes the effectiveness of FOLE: http://nbcnews.to/11vbL2E 

Related blog posts:

Neonatal cholestasis and Down syndrome

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A retrospective Swedish study adds some useful information on the incidence of neonatal cholestasis with Down syndrome (J Pediatr 2012; 161: 899-902).

In this retrospective study of all neonates born between January 2005-September 2011 in Stockholm , a total of 206 newborns were identified as having Down syndrome.  This represents an incidence of 1 in 880 newborns.

  • 3.9% (n=8) had cholestasis
  • 47% (n=96) had congenital heart disease
  • 11.2% (n=23) had GI disorders: duodenal stenosis (n=7), duodenal atresia (n=4), omphalocele (n=3), Hirschsprung disease (n=2), esophageal atresia/duodenal atresia (n=1), jejunal atresia (n=1), and other conditions (n=5)
  • 3.4% (n=7) had bone marrow diseases including transient abnormal myelopoiesis

All eight children with cholestasis had congenital heart disease.  However, severe cholestasis was only seen in the 3 patients with concomitant bone marrow disease. Two of these patients died and one developed cirrhosis/chronic liver disease. All cholestatic patients had involvement of other organ systems.  As this was a retrospective study, some milder cases of neonatal cholestasis may not have been detected.

In children with concomitant bone marrow disease, neonatal cholestasis may forebode an increased risk for severe disease.  While all 3 of the newborns with severe disease also had congenital heart disease, most infants with combined congenital heart disease/cholestasis (n=5) did not have a severe case.

Related blog posts

Itchy and Scratchy

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On TV’s “The Simpsons,” “Itchy” is a sadistic blue mouse and “Scratchy” is a hapless black cat (The Itchy & Scratchy Show – Wikipedia, the free encyclopedia, The Simpsons – Itchy and Scratchy – YouTube).  In real life being real itchy is not a joke; it is a common problem with cholestatic liver disease.  Beneficial treatments for pruritus may be partly due to their effects on serum autotaxin (Hepatology 2012; 56: 1391-1400, editorial 1194).

In this study, blood was drawn from different treatment groups:

  • 17 patients receiving colsevelam (a bile acid sequestrant)
  • 10 patients receiving MARS (molecular absorbance recirculating system)
  • 6 patients receiving rifampicin
  • 5 patients receiving nasobiliary drainage
  • Also, autotaxin levels were drawn from healthy controls, atopic dermatitis, Hodgkin’s disease (with and without pruritus), uremic patients, and cholestatic patients without pruritus

The most common diagnosis in all of the cholestatic groups was primary biliary cirrhosis; though some patients had primary sclerosing cholangitis, progressive familial intrahepatic cholestasis, benign recurrent intrahepatic cholestasis or other liver disorders.

Key findings:

  • Serum autotaxin is increased in pruritic cholestatic liver patients but not in other forms of pruritus.  In addition, autotaxin is normal in cholestatic patients without pruritus.
  • The level of autotaxin correlates closely with the effectiveness of the treatment as gauged by itch intensity

The reasons for pruritus in cholestasis have not been clear.  Several theories have been advanced regarding pathogenesis.  Specifically, retained bile acids and increased opiate activity have been thought to play a role.  More recently, lysophosphatidic acid (LPA) levels have been noted to be elevated in the serum of patients with cholestatic itch.  Injection of LPA into mice results in scratching activity.  LPA activity is a consequence of autotaxin.

Other important points:

  1. Rifampicin has been shown to reduce autotaxin levels in vivo.
  2. MARS and nasobiliary drainage do not directly drain autotaxin; their effects on autotaxin must result by eliminating another factor which stimulates autotaxin production.
  3. Autotaxin is likely to be a useful objective biological marker for pruritus and to evaluate potential novel treatments.
  4. Autotaxin elevation can occur in other noncholestatic inflammatory disease in which pruritus is not a feature; thus, the reasons for pruritus are likely multifactorial and not due to a simple causal role for autotaxin.

Related blog entries:

Challenges with primary sclerosing cholangitis | gutsandgrowth

BRIC, PFIC, and nasobiliary drainage | gutsandgrowth

Additional references:

  • -J Hepatol 2009; 51: 237-67.  EASL practice guidelines on mgt of cholestatic liver disease
  • -JPGN 2010; 51: 787.  Use of naltrexone in severe pruritus due to cholestasis: 1-2/kg/day. n=4.
  • -JPGN 2008; 46: 241.  Excellent review.  BRIC caused by FIC1 mutations (same as PFIC1).  Nasobiliary drainage of bile may be helpful.
  • -Hepatology 2007; 45: 666.  Use of sertraline (75-100mg; start with 25mg –in adults)
  •  -Clin Gastro & Hep 2007; 5:776 Use of zoloft for pruritus in cholestasis.
  • -Hepatology 2005; 42: 222. summary of cholestasis workshop
  • -JPGN 1999; 29: 442.  Rifampin treatment for cholestasis. 90% response, 40% complete response.  Extrahepatic cases c much better response.  No toxicity observed.
  • -Clin Liver Dis 2006; 10: 27-53.

Gene:                       Disorder (protein)

  1. ABCB11                     PFIC 2, BRIC 2 (BSEP)
  2. ABCB4                       PFIC 3, ICP (MDR3)
  3. CFTR                         CF (CFTR)
  4. ATP8B1                      PFIC1 -Byler’s (FIC1), BRIC, GFC -Greenland Familial
  5. CLDN1                       NISCH (Claudin 1) -neonatal sclerosing cholangitis/icthyosis VPS33B                     ARC syndrome (Vascular protein sorting 33) -arthrogryposis-   renal dysfn-cholestasis, low GGT
  6. AKR1D1                    BAS: Bile acid synthetic defect: neonatal cholestasis with giant cell hepatitis   (5Beta-reductase)
  7. HSD3B7                    BAS (C27-3Beta-HSD)
  8. CYP7BI                     BAS (CYP7BI)
  9. TJP2 (ZO-2)              FHC: Familial hypercholanemia (tight junction protein)
  10. BAAT                        FHC (BAAT)
  11. EPHX1                     FHC (epoxide hydrolase)
  12. JAG1                        Alagille (JAG1) JAG1 is transmembrance cell-surface protein important in   regulating cell fate during embryogenesis
  13. PKHD1                     ARPKD (fibrocystin -important in ciliary function and tubulogenesis)
  14. PRKCSH                  ADPLD (hepatocystin)
  15. ABCC2                     Dubin-Johnson syndrome (MRP2)
  16. CIRH1A                    NAIC -N Amer Indian childhood cirrhosis (Cirhin)

TPN cycling

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A randomized prospective study of early parenteral nutrition cycling was not helpful in reducing parenteral nutrition associated cholestasis (PNAC): J Pediatr 2012; 161: 229-33.

This study enrolled preterm infants <1250 g in the first five postnatal days to either cycled (n=34) or continuous parenteral nutrition (n=36).  Cholestasis was defined as direct bilirubin >2 mg/dL. The study indicated that intralipid 20% was administered in all patients over 18 hours; the exact amount is not clear, though in the cycled group, patients received 3 g/kg/day on postnatal day 3.9 ± 2.6.  All patients received dextrose over 24 hours; only the amino acid (TrophAmine) infusion varied: 20 hours compared with 24 hours.

  • PNAC in each group was nearly identical, 32% vs 31% as were bilirubin and transaminase values.
  • While the study was randomized, the cycled group did have more frequent late-onset sepsis 22 (65%) compared with 14 (39%) which reached statistical significance.
  • In addition, a trend towards more frequent non-surgical NEC in cyclical group was noted as well: 6 (18%) compared with 3 (8%).
  • PNAC was associated with days until full enteral nutrition/duration of parenteral nutrition and bronchopulmonary dysplasia.

The higher incidence of late-onset sepsis could have occurred randomly and affected the results; alternatively, the higher rate could reflect an increased risk of sepsis due to doubling the frequency of central line access.

This study was  only powered to detect a 25% difference between the groups; the authors estimate that a study with 290 patients would be needed in each group to identify a reduction of 10% in the incidence of PNAC.  As such, this study leaves open the possibility that cycled parenteral nutrition may be helpful in a smaller percentage, particularly if efforts are made to eliminate central line infections.  More promising efforts to minimized PNAC are noted in previous blog entries:

PNAC, PNALD, and IFAC

Optimizing lipids to minimize cholestasis

More on PNAC

Four advances for intestinal failure

Diagnosing biliary atresia earlier

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Biliary atresia (BA) is often suspected among infants with prolonged jaundice. In fact, efforts have been underway for a long time to encourage fractionation of the bilirubin values to look for conjugated hyperbilirubinemia, especially in infants that remain jaundiced at three weeks of life.  While this is still good advice, given the lack of success in implementation, there is good evidence that obtaining a fractionated bilirubin at any time point can help identify cholestasis associated with BA.

A recent article by Karpen et al (Pediatrics 2011; 128:. e1428 -e1433) indicates that direct bilirubin values are elevated beginning within the first one to two days in patients with BA.  In their cohort of 61 BA subjects, 56% had newborn fractionated bilirubin values.  Every BA patient had elevated direct bilirubin, on average 1.4 ± 0.43 mg/dL (normal <0.5) (compared with control patients:  0.19 ± 0.075 mg/dL, P < .0001).  Also, another important finding was that early on the ratio of direct bilirubin to total bilirubin was normal in 79%; normally this ratios is ≤0.2.  As such, all patients with increased direct bilirubin need to be followed closely.

Related blog entries:

Outcomes of Biliary Atresia

MicroRNAs and biliary atresia

Bleeding due to vitamin K deficiency

Bleeding due to vitamin K deficiency

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With cholestasis in infancy, Bill Balistreri taught me that there were four potential emergencies:

  • Bleeding due to vitamin K deficiency or coagulopathy
  • Hypoglycemia
  • Sepsis
  • Metabolic poisoning with formula (in patients with galactosemia)

Once these issues have been considered, then it is appropriate to start investigating the etiology of the cholestasis.

One of the more dramatic complications is intracranial hemorrhage (ICH). While ICH is a well-recognized complication of cholestasis in infancy, the long-term outcomes are not well-characterized. A report from Japan adds some insight (JPGN 2012; 54: 552-57).

Among a retrospective review of 83 infants with biliary atresia (BA) between 1979 to 2009, ICH occurred in 8% despite oral vitamin K prophylaxis (2 mg).  The onset of ICH was between 47-76 days after birth and was prior to surgery.  Coagulopathy was noted in all cases, which improved with vitamin K intravenously.  Two infants required craniotomy.  In 5 of 7 cases, neurologic sequelae were noted including developmental delay in three, epilepsy in one, and mild hemiparesis in two.

Additional references:

  • Blood Rev 2009; 23: 49-59.  Review of vitamin K deficiency.
  • Pediatrics 2008; 121:e857.  Vitamin K deficiency common in cholestatic breastfed babies.  Can be prevented with 1mg po each week or single IM dose of 2mg.
  • Eur J Pediatr Surg 2005; 15: 295-9.  Bleeding disorder as 1st symptom of BA.
  • Pediatr Neurosurg 2006; 42: 362-7.  ICH due to vitamin K deficiency.
  • Pediatrics 2006; 118: e1657.  dose of 0.2mg effective for median of 25days (w/o toxicity/accumulation of K1O) in infants <32weeks gestation.

More on PNAC

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In a previous blog entry (PNAC, PNALD, and IFAC), reduction in intralipids was shown to improve parenteral nutrition associated cholestasis (PNAC).  This change in the use of parenteral nutrition (PN) and others are emphasized in a review article by the American Pediatric Surgical Association (J Ped Surg 2012; 47: 225-40).

This review tries to provide evidence-based guidelines for PNAC with ratings of the evidence for each of their recommendations.

A summary of their findings is given in Figure 1 of the article.  Key points:

  • PN duration is a significant predictor for cholestasis
  • NEC & sepsis both play a role in the development of PNAC
  • Insufficient data to determine if antibiotics used to decrease bacterial translocation/hepatocyte damage may be beneficial
  • Fat emulsion restriction may reduce PNAC without detriment to growth
  • Fish-oil based lipid emulsions are safe and effective for PNAC.  “Despite the promise of Omegaven…the literature is insufficient to provide a recommendation higher than grade C.”  (Grade C= “possibly effective, ineffective, or harmful;” requires at least 2 convincing class III studies [class III studies generally are non-randomized non-blinded studies]).  Information to obtain Omegaven:

http://www.oley.org/documents/How_Physicians_Can_Obtain_Omegaven.pdf
http://www.oley.org/lifeline/PN_Liver_Disease.html

  • Strong evidence that higher initial protein load does not increase the risk of PNAC
  • Strong evidence that trophic feeds are beneficial to reduce PNAC
  • Weak/conflicting evidence that there is any benefit of Aminosyn over Trophamine
  • Weak evidence to support the routine removal of copper or manganese from PN as a prophylactic strategy to prevent PNAC
  • Weak evidence to support prophylactic cycling of PN to reduce PNAC.  There are also concerns about the development of hypoglycemia in preterm infants off of PN
  • Use of CCK is not recommended
  • Oral bile acids may result in improvement
  • Erythromycin may promote motility and facilitate enteral feeds, thereby reducing PNAC

PNAC, PNALD, and IFAC

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Intravenous lipids may cause parenteral nutrition associated cholestasis (PNAC), parenteral nutrition associated liver disease (PNALD), or intestinal failure associated cholestasis (IFAC) (J Pediatr 2012; 160: 421-7 & editorial 361-2).  PNAC refers to cholestasis due to parenteral nutrition and PNALD refers to PNAC that has progressed to liver dysfunction or permanent liver injury.

In a previous blog (Four advances for intestinal failure), one of the advances for intestinal failure that was noted was the reduction of lipid infusions with parenteral nutrition which reduces IFAC.  This study adds additional information to this area.  In this prospective study, 31 patients were enrolled in a reduced IV fat emulsion group and compared with a matched historical control group.  The reduced fat group received 1gm/kg of a standard soybean-based lipid emulsion (liposyn 20%) twice weekly.  Patients were eligible if they received PN for >2 weeks and had a direct bilirubin >2.5 mg/dL.

Outcomes:

  • Total bilirubins dropped 0.73 mg/dL each week in the reduced fat group; in the control group, the bilirubin increased 0.29 mg/dL each week
  • Growth was similar in both groups
  • Essential fatty acid deficiency (biochemical not clinical features) was identified in 13 of 31 infants among the restricted IV fat emulsion group.

Essential fatty acid deficiency was defined as having a triene: tetraene ratio >0.05 (mild), >0.2 (moderate) or >0.4 (severe).

Limitations:

  • Historical control group & small study population
  • Fat-restricted group received enteral antibiotics which may have helped reduce cholestasis
  • Majority of patients with relatively short duration of TPN: 18 of 31 for less than one month

The reasons why lipids may contribute to PNAC/PNALD/IFAC include the presence of phytosterols.  This in turn may damage hepatocytes via the farnesoid X receptor.  One other aspect of the study was that the fat-restricted cohort had a higher mortality.  This was thought to be related to the cohort being sicker rather than to any nutritional effect.  Specific causes of death included respiratory failure in a patient with an abdominal wall defect, chylothorax/sepsis in a patient with a congenital diaphragmatic hernia, and cardiopulmonary failure in a patient with pulmonary hypoplasia.

The article does throw into question whether the use of a fish oil lipid preparation is needed to improve cholestasis.  In studies supporting fish oil preparations, a confounder was that the total lipid administered was reduced to 1 gm/kg/day in comparison to soybean lipids which were administered at 2-3 gm/kg/day.  This study suggests that reducing the total amount of lipid infusion is the more important factor.

The accompanying editorial makes a couple of useful points:

  • Increasing enteral feeds (>50%) is as effective as using less intravenous lipids
  • Use of standard lipids at 1gm/kg/day decreased IFAC from 15% to 4% in their intestinal failure patient population
  • Drastic reductions in lipids lead to essential fatty acid deficiency and should be avoided.
  • Use of Omegaven has not been shown to prevent liver fibrosis even with resolution of cholestasis; similarly, these studies do not inform fully on the long-term liver effects of reducing standard lipids
  • Neurologic followup will be important
  • Explains “Morton’s fork.”  John Morton was a 16th century Archbishop who wanted to increase taxes on people who were living lavishly.  In addition, he wanted to increase taxes on those living modestly (must be hiding wealth).

Additional references:

  • -NEJM 2010; 362: 181.  Letter to editor describes use of fish oil in (n=125) Boston pediatric patients.
  • -JPGN 2009; 48: 209. n=12. SBS.  9/12 improved with Omegaven. 3 had transplant (L-ITx). No controls.
  • -Pediatrics 2008; 121: e678-86. n=18.  Use of fish oil improved cholestasis compared to historical controls.
  • -Pediatrics 2006; 118: e197-e201.  Reversal of TPN-AC c IV omega-3 fatty acids (fish oil-derived) instead of intralipids

Four advances for intestinal failure

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Several advances in the management of intestinal failure have the potential to improve the outlook for our intestinal failure (IF) (aka Short Bowel Syndrome) patients (JPEN 2012; 36: 36S-42S).

Although IF patients already have improving survival with rates of 80-95% over followup ranging from 1-5 years, many still do not survive, primarily due to bacterial infections or chronic liver disease.  Ongoing research has made some promising steps in the management of these pediatric patients.  This article focuses on four of these steps.

1. Citrulline monitoring

  • Major source of citrulline is enterocyte production.  Citrulline is an amino acid not encoded in human genetic code; it is present in some proteins as a product of posttranslational modification.
  • Watermelon is one of few dietary sources.
  • Useful biomarker for bowel length/absorption –independent of inflammatory markers
  • Levels >15-20 μmol/L indicate good likelihood of achieving enteral autonomy
  • Levels <12μmol/L indicate a very low likelihood of achieving enteral autonomy

2. Teduglutide therapy

  • Analog of glucagon-like peptide 2 (GLP-2) but harder to degrade (longer half-life)
  • Preliminary studies in adults indicate improvement in absorption and villous histology after subcutaneous administration for three weeks.  Improvements reverse when drug is discontinued.
  • Since GLP-2 is produced by colon & increased in IF (if colon present), unclear whether exogenous administration will be as beneficial in patients with residual colon

3. Lipid minimization &/or fish oil lipids

  • Cholestasis increases in patients receiving more than 1 g/kg/day of intralipids (soy based).
  • Fish oil (Omegaven) has shown benefit in lowering cholestasis in numerous case reports.  This may be due the high content of anti-inflammatory ω-3 fatty acids.
  • Another preparation SMOFLipid is a mixed formulation and may be safer than pure fish oil; randomized controlled studies of both of these lipid formulations are underway.
  • Fish oil has not been shown to improve histology
  • Parenteral nutrition associated liver disease (PNALD) may improve with lowering lipids & may not need omegaven

4. Ethanol locks

  • May be beneficial in treating and preventing central line infections.  In both situations, in small studies, ethanol locks lowered incidence of recurrent infections.
  • Six studies involving 75 patients (66 pediatric patients) lowered infection rates from approximately 10 per 1000 catheter days to 2 per 1000 catheter days.
  • Ethanol concentrations were mostly 70% in these studies, though 25% has been used.
  • Dwell times ranged from 2-14 hours.
  • Randomized studies are in progress.
  • Fewer infections should reduce the likelihood of death from sepsis and death due to loss of venous access.

Additional references:

  • -NEJM 2010; 362: 181.  Letter to editor describes use of fish oil in (n=125) Boston pediatric patients.
  • -JPGN 2009; 48: 209. n=12. SBS.9/12 improved with omegaven. 3 had transplant (L-ITx). No controls.
  • -NEJM 2009; 361: 998. Intestinal Rx.  Review claims ~90% 1yr survival. 47% 5yr, 61% 3yr (expecting to go higher)
  • -JPGN 2009; 48: 334. Isolated liver w SBS feasible IF 50cm small bowel remaining or 30cm w ICV, 50% enteral nutrition >4 weeks with good growth, no dysmotility.
  • -Pediatrics 2008; 121: e678. n=18. use of fish oil improved cholestasis compared to historical controls.
  • -Gastroenterology 2008; 135: 61, 303. Survival of ITx (vs. HAL).  In many conditions, better off from survival standpoint without Tx. Tx if failure of TPN (severe liver dz/thrombosis of >/= 2 central veins, multiple bouts of sepsis/frequent dehydration), high risk of death, severe short bowel (<10cm in infants and <20cm in adults), pseudoobstruction, unwillingness to accept long-term tpn. 93% of TPN patients who did not have TPN-complications had 93% survival rate.  Thus, TPN is first line Rx as survival and quality of life often better.
  • -Pediatrics 2006; 118: e197-e201.  Reversal of TPN-AC c IV omega-3 fatty acids (fish oil-derived) instead of intralipids
  • -Liver Transplantation 2006; 12: 1062, 1040. Liver transplant alone reasonable to consider in some SBS patients who tolerate >50% enteral therapy and are less than 2 years old.
  • -Gastroenterology 2006; 130. Supp 1. Summary of NIH workshop on intestinal failure. TX Indications: Liver disease, thrombosis of major veins, recurrent catheter-related sepsis, frequent severe dehydration/electrolyte imbalance.
  • -JPGN 2005; 41: 47A (pg507). Poor prognosis: <40cm, needing >40kcal/kg PN, increased bili (>150 μmol/L)
  • -J Pediatr 2005; 146: 542. Serum citrulline > 19 μ/L associated with bowel adaptation/weaning off HAL.
  • -J Pediatr 2004; 145: 157-163. Survival of SBS with as little as 15
  • -Arch Pediatr Adolesc Med 2006; 160: 104953.  Use of ethanol lock (70%, 08-1.4mL for 12-24hrs, then withdraw). n=51.  High success rate in salvaging line
  • -J Pediatr 2001; 139: 27-33. Review of 30 pts. 3 of 30 pts with bowel length 40cm or less able to wean PN.
  • -Gastroenterology 2001; 120: 806-815. Glucagon-like peptide 2 improves nutrient absorption marginally.