Cholestatic jaundice and congenital hypopituitarism

A Rare Case of Severe Jaundice in a Panhypopituitarism Patient

Hyperbilirubinemia and transaminitis are rarely associated with a disorder of endocrine function. It mostly manifests as a cholestatic pattern of liver injury. Herein, a 25-year-old female patient with a past medical history of congenital hypopituitarism due to pituitary ectopia presented with serum direct bilirubin level of 9.9 mg/dL and aspartate transaminase (AST)/alanine transaminase (ALT) of 60/47 U/L. All tests for chronic liver disease imaging and liver biopsy were normal. She was found to have central hypothyroidism and low cortisol level. She was started on intravenous (IV) levothyroxine 75 µg daily and IV hydrocortisone 10-5 mg AM/PM. She was discharged on oral levothyroxine 88 µg daily and hydrocortisone orally 10 mg twice daily. Follow-up labs 1 month later showed completely normal liver function test. In conclusion, hyperbilirubinemia due to congenital hypopituitarism can occur in adults. Delayed recognition of underlying endocrine disorder as a cause of hyperbilirubinemia and hepatocellular inflammation can result in end-stage liver damage due to prolonged cholestasis.

Novel Melano-Cortin-2-Receptor Gene Mutation Presenting With Infantile Cholestasis: A Case Report

Introduction:

For many years, congenital panhypopituitarism has been recognized to cause infantile cholestasis. However, the isolated cortisol deficiency as a cause of cholestasis and liver failure was rarely reported.

Case description:

A 32-days old male infant presented to the hepatology clinic with infantile cholestasis. His initial workup revealed alanine transaminase (ALT) level of 138 U/L, aspartate transaminase level of 76 U/L, total bilirubin (T.Bil) of 103 mmol/L, direct bilirubin of (D.Bil) 83 mmol/L, gamma-glutamyl transpeptidase (GGT) level of 28 U/L with normal prothrombin time (PT) of 13 seconds. One week later, the patient developed severe bronchiolitis necessitating mechanical ventilation associated with acute liver failure and worsening cholestasis. His ALT increased to 303.5 U/L and direct bilirubin increased to 204 mmol/L with prolongation of PT to 18.9 seconds reflecting derangement in synthetic liver functions. There was associated hypoglycemia, hyponatremia and high normal potassium level with a picture of adrenal insufficiency. Hormonal workup and genetic testing revealed isolated cortisol deficiency with a novel homozygous mutation c.763_764delAT (p. Met255ValfsX17) in Melanocortin 2 receptor gene (MC2R) and the patient was diagnosed as familial primary glucocorticoid deficiency. The patient was maintained on cortisol replacement therapy with the resolution of cholestasis and normalization of liver functions.

Conclusions:

Patients presenting with infantile cholestasis associated with documented hypoglycemia should alert pediatricians about the possibility of familial glucocorticoid deficiency and prompt investigation of adrenal function should be considered. Cortisol replacement therapy leads to the resolution of cholestasis.

Genetic causes of hypopituitarism

Hypopituitarism in neonates is rare, but has life-threatening complications if untreated. This review describes the features of hypopituitarism and the evidence for which infants in whom a genetic cause should be suspected. Importantly, neonates are often asymptomatic or present with non-specific symptoms. Hypopituitarism can be due to abnormal gland development as a result of genetic defects, which result from mutations in gene coding for transcription factors which regulate pituitary development. The mutations can be divided into those causing isolated hypopituitarism or those causing syndromes with associated hypopituitarism. The latter involve mutations in transcription factors which regulate pituitary, as well as extra-pituitary development. There is a paucity of evidence as to which patients should be investigated for genetic mutations, but detailed clinical and biochemical phenotyping with magnetic resonance imaging of the pituitary gland could help target those in whom genetic investigations would be most appropriate.

Reduced Hepatocellular Expression of Canalicular Transport Proteins in Infants with Neonatal Cholestasis and Congenital Hypopituitarism

OBJECTIVE

To assess whether prolonged neonatal cholestasis, described in congenital hypopituitarism and septo-optic dysplasia (SOD), is associated with altered expression of selected canalicular ectoenzymes and canalicular transport proteins.

STUDY DESIGN

Children with congenital hypopituitarism (n = 21), SOD (n = 18), and cholestasis seen in our center over 26 years were reviewed. Histopathologic findings in archival liver biopsy specimens were assessed (n = 10) and in those with low/normal levels of serum γ-glutamyltransferase (GGT) activity despite conjugated hyperbilirubinemia, expression of canalicular ectoenzymes and canalicular transport proteins was evaluated immunohistochemically.

RESULTS

Patients presented at a median age of 8 weeks (range 3-20 weeks) with median total bilirubin 116 µmol/L (45-287 µmol/L), GGT 95 IU/L (25-707 UI/L), and serum cortisol 51 nmol/L (17-240 nmol/L). All but 3 had low free thyroxin (median 9.6 pmol/L [6.8-26.9]) with increased thyroid-stimulating hormone levels (median 5.95 mU/L [<0.1-9.24]). Liver histologic features included moderate-to-severe intralobular cholestasis with nonspecific hepatitis, giant-cell transformation of hepatocytes, and fibrosis. In all, immunohistochemical staining for canalicular ectoenzymes and canalicular transport proteins revealed a degree of reduced expression, associated with normal serum GGT values in 6 of the 10 patients, and another 6 nonbiopsied infants with cholestasis also had low/normal serum GGT activity. Sequencing of ABCB11 and ATP8B1 performed in 6 of the biopsied patients did not identify pathogenic mutations. Following replacement therapy, biochemical evidence of hepatobiliary injury resolved in all children within a median period of 6 months.

CONCLUSION

Hepatobiliary involvement in congenital hypopituitarism associated with SOD has a good prognosis, but its etiology remains uncertain. Immunohistochemical expression of canalicular transport proteins was reduced in available liver samples.

Pilot Neonatal Screening Program for Central Congenital Hypothyroidism: Evidence of Significant Detection

BACKGROUND/AIM

Congenital hypothyroidism (CH) is a heterogeneous entity. Neonatal screening programs based on thyrotropin (TSH) determination allow primary CH diagnosis but miss central CH (CCH). CCH causes morbidity, alerts to other pituitary deficiencies, and is more prevalent than previously thought. We aimed at developing a pilot neonatal screening program for CCH detection.

PATIENTS AND METHODS

A prospective 2-year pilot neonatal screening study based on simultaneous dried blood specimen TSH and thyroxine (T4) measurements was implemented in term newborns aged 2-7 days. Those with T4 ≤4.5 µg/dL (-2.3 SDS) and TSH <10 mIU/L were recalled (suspicious of CCH) and underwent clinical and biochemical assessment performed by expert pediatric endocrinologists.

RESULTS

A total of 67,719 newborns were screened. Primary CH was confirmed in 24 (1: 2,821). Forty-four newborns with potential CCH were recalled (recall rate 0.07%) at a mean age of 12.6 ± 4.8 days. In this group, permanent CCH was confirmed in 3 (1: 22,573), starting L-T4 treatment at a mean age of 12.3 ± 6.6 days; 14 boys showed T4-binding globulin deficiency (1: 4,837); 24 had transient hypothyroxinemia (21 non-thyroidal illness and 3 healthy); and 3 died before the confirmation stage. According to initial free T4 measurements, CCH patients had moderate hypothyroidism.

CONCLUSIONS

Adding T4 to TSH measurements enabled the identification of CCH as a prevalent condition and contributed to improving the care of newborns with congenital hypopituitarism and recognizing other thyroidal disorders.

Hypothalamus-Pituitary-Adrenal Dysfunction in Cholestatic Liver Disease

The Hypothalamic-Pituitary-Adrenal (HPA) axis has an important role in maintaining the physiological homeostasis in relation to external and internal stimuli. The HPA axis dysfunctions were extensively studied in neuroendocrine disorders such as depression and chronic fatigue syndrome but less so in hepatic cholestasis, cirrhosis or other liver diseases. The HPA axis controls many functions of the liver through neuroendocrine forward signaling pathways as well as negative feedback mechanisms, in health and disease. This review describes cell and molecular mechanisms of liver and HPA axis physiology and pathology. Evidence is presented from clinical and experimental model studies, demonstrating that dysfunctions of HPA axis are correlated with liver cholestatic disorders. The functional interactions of HPA axis with the liver and immune system in cases of bacterial and viral infections are also discussed. Proinflammatory cytokines stimulate glucocorticoid (GC) release by adrenals but they also inhibit bile acid (BA) efflux from liver. Chronic hepatic inflammation leads to cholestasis and impaired GC metabolism in the liver, so that HPA axis becomes depressed. Recently discovered interactions of GC with self-oscillating transcription factors that generate circadian rhythms of gene expression in brain and liver, in the context of GC replacement therapies, are also outlined.

Cholestasis caused by panhypopituitarism and acquired cytomegalovirus infection in a 2-month-old male infant: A case report

RATIONALE

Septo-optic dysplasia (SOD) is a rare congenital disorder that may cause jaundice in infants. However, it is usually prone to neglect and misdiagnosis in infants with cholestasis because endocrine disorder such as panhypopituitarism is rare in the cause of infantile cholestasis. We report a case of SOD concurrent with acquired cytomegalovirus (CMV) infection, who presented with prolonged jaundice as the first clinical sign.

PATIENT CONCERNS

The patient was a 2-month-old male infant who presented with cholestasis, combined with fever and panhypopituitarism.

DIAGNOSES

He was diagnosed with SOD and acquired CMV infection.

INTERVENTIONS

He was treated with hormone replacement therapy and ganciclovir.

OUTCOMES

After correction of the pituitary hormone deficiency and ganciclovir treatment, significant improvements of cholestasis, retinal lesions, and growth rate were seen in our patient.

LESSONS

Although an endocrine disorder such as panhypopituitarism is rare in the cause of neonatal or infantile cholestasis, we must keep this reason in mind.

Guideline for the Evaluation of Cholestatic Jaundice in Infants: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition

Cholestatic jaundice in infancy affects approximately 1 in every 2500 term infants and is infrequently recognized by primary providers in the setting of physiologic jaundice. Cholestatic jaundice is always pathologic and indicates hepatobiliary dysfunction. Early detection by the primary care physician and timely referrals to the pediatric gastroenterologist/hepatologist are important contributors to optimal treatment and prognosis. The most common causes of cholestatic jaundice in the first months of life are biliary atresia (25%-40%) followed by an expanding list of monogenic disorders (25%), along with many unknown or multifactorial (eg, parenteral nutrition-related) causes, each of which may have time-sensitive and distinct treatment plans. Thus, these guidelines can have an essential role for the evaluation of neonatal cholestasis to optimize care. The recommendations from this clinical practice guideline are based upon review and analysis of published literature and the combined experience of the authors. The committee recommends that any infant noted to be jaundiced after 2 weeks of age be evaluated for cholestasis with measurement of total and direct serum bilirubin, and that an elevated serum direct bilirubin level (direct bilirubin levels >1.0 mg/dL or >17 μmol/L) warrants timely consideration for evaluation and referral to a pediatric gastroenterologist or hepatologist. Of note, current differential diagnostic plans now incorporate consideration of modern broad-based next-generation DNA sequencing technologies in the proper clinical context. These recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the care of all infants with cholestasis. Broad implementation of these recommendations is expected to reduce the time to the diagnosis of pediatric liver diseases, including biliary atresia, leading to improved outcomes.

Cholestasis Reveals Severe Cortisol Deficiency in Neonatal Pituitary Stalk Interruption Syndrome

OBJECTIVES

Cholestasis has been reported during the course of congenital hypothalamic-pituitary deficiency, but crucial information is lacking regarding both its origin and prognosis. We aimed to characterize the course of cholestasis and factors contributing to it in patients with deficiency due to pituitary stalk interruption syndrome (PSIS).

METHODS

We conducted a retrospective single-center, case-cohort study including 16 patients with PSIS diagnosed before one year of age. We collected clinical and biological parameters from medical records and compared the characteristics of the endocrine syndrome in PSIS patients with and without cholestasis.

RESULTS

5/16 patients had cholestasis, all with a neonatal onset and multiple hypothalamic-pituitary deficiency. Patients with cholestasis presented with lower Apgar score and higher rate of ophthalmic malformations: 3/5 vs 1/11, p = 0.03 and 5/5 vs 4/11, p = 0.02, respectively. The plasma cortisol level was strongly decreased in patients with cholestasis: 12.4 ng/mL (8-15 ng/mL) vs 79.4 ng/mL (10-210 ng/mL), p = 0.04. Cholestasis resolved within 9 months following hormone supplementation. No development of chronic liver disease was observed during a median follow-up of 9.4 years (range, 1.3-13.3 years).

CONCLUSIONS

Cholestasis is a frequent symptom at presentation of PSIS during the neonatal period that may help earlier diagnosis and that indicates a profound cortisol deficiency.

Cholestasis in the newborn and infant

Neonatal cholestasis occurs in approximately 1 in 2500 term infants, the most common underlying disease being biliary atresia, viral infections and α1-antitrypsin deficiency. The incidence of cholestasis is much higher in extremely premature newborns. The etiology of biliary atresia remains unclear, which in turn makes the search for additional treatments to surgery challenging. Reliable non-invasive tools to differentiate biliary atresia from other forms of neonatal cholestasis need to be further investigated. Despite important findings in the last decades, the pathogenesis of cholestatic liver disease in α1-antitrypsin deficiency remains to be clarified. Any such explanation would also need to explain why only a minority of individuals with PiZZ phenotype develop liver disease. For other genetic diseases causing neonatal cholestasis, such as Alagille's syndrome and progressive familial intrahepatic cholestasis the breakthrough within the field of molecular biology has definitely deepened our understanding of both etiology and pathogenesis. However, the correlation between genotype and phenotype is rarely obvious and for several patients with the seemingly correct phenotype no known genetic mutation is detected. A stepwise approach to the management of cholestasis in the newborn and infant is suggested, where percutaneous liver biopsy is of value to select patients with suspected biliary atresia for laparotomy.

Neonatal cholestasis in congenital pituitary hormone deficiency and isolated hypocortisolism: characterization of liver dysfunction and follow-up

INTRODUCTION

Neonatal cholestasis due to endocrine diseases is infrequent and poorly recognized. Referral to the pediatric endocrinologist is delayed.

OBJECTIVE

We characterized cholestasis in infants with congenital pituitary hormone deficiencies (CPHD), and its resolution after hormone replacement therapy (HRT).

SUBJECTS AND METHODS

Sixteen patients (12 males) were included; eleven with CPHD, and five with isolated central hypocortisolism.

RESULTS

Onset of cholestasis occurred at a median age of 18 days of life (range 2-120). Ten and nine patients had elevated transaminases and γGT, respectively. Referral to the endocrinologist occurred at 32 days (range 1 - 72). Remission of cholestasis occurred at a median age of 65 days, whereas liver enzymes occurred at 90 days. In our cohort isolated, hypocortisolism was a transient disorder.

CONCLUSION

Cholestasis due to hormonal deficiencies completely resolved upon introduction of HRT. Isolated hypocortisolism may be a transient cause of cholestasis that needs to be re-evaluated after remission of cholestasis.

Isolated cortisol deficiency: a rare cause of neonatal cholestasis

For decades, congenital panhypopituitarism has been recognized to cause infantile cholestasis. However, the identity of the hormone whose deficiency causes such derangement of the liver is not clear. Here, we report four cases of isolated severe cortisol deficiency presenting with neonatal cholestasis and hypoglycemia, of whom two had familial primary glucocorticoid deficiency and the other two had isolated adrenocorticotropin deficiency. The resolution of cholestasis by hydrocortisone replacement therapy suggests a causal relationship between cortisol deficiency and the development of neonatal cholestasis. In conclusion, the presentation of a young infant with cholestasis and hypoglycemia should alert pediatricians to the possibility of cortisol deficiency and prompt investigation of adrenal function should be undertaken.

[Diagnosis of congenital endocrinological disease in newborns with prolonged jaundice and hypoglycaemia]

INTRODUCTION

The association of prolonged neonatal jaundice and hypoglycaemia may be secondary to an endocrinological disease. Pituitary insufficiency and primary adrenal insufficiency are the most likely endocrine diseases that need to be ruled out.

MATERIAL AND METHODS

We retrospectively analysed the clinical and laboratory characteristics of thirteen patients referred to the Hospital de Niños Ricardo Gutiérrez between years 2003 and 2008 due to prolonged neonatal jaundice and hypoglycaemia secondary to pituitary insufficiency in twelve patients, and in one secondary to primary adrenal insufficiency.

RESULTS

All patients had a history of neonatal hypoglycaemia. Ten patients had conjugated hyperbilirubinaemia and six also had elevated transaminases. Combined pituitary hormone deficiency was observed in the twelve hypopituitarism patients. Hormonal replacement normalised liver function and resolved the prolonged jaundice in all the patients. None of them underwent liver biopsy. Hypoglycaemia also remitted after hormonal therapy.

CONCLUSIONS

Prolonged or cholestatic jaundice associated with neonatal hypoglycaemia is highly likely to be due to pituitary hormone deficiency or primary adrenal insufficiency. Early diagnosis and treatment of these children reverts the prolonged jaundice and prevents morbidity and mortality due to recurrent hypoglycaemia and hormone deficiencies.

Neonatal giant cell hepatitis: histological and etiological findings

BACKGROUND

Neonatal giant cell hepatitis (NGCH) is an important diagnostic consideration in infants who present with jaundice. In this study, we examined 2 separate tertiary care center cohorts of individuals with NGCH to better understand the potential etiologies and their histological correlates.

METHODS

All liver biopsies (1984 to 2007) with a histological diagnosis of NGCH were reviewed from 2 tertiary care centers. Cases diagnosed at the time of biopsy as biliary atresia, paucity of intrahepatic bile ducts, total parenteral nutrition associated liver injury, or α-1-antitrypsin deficiency were excluded. Liver biopsies were examined for cholestasis, giant cell change, extramedullary hematopoiesis, inflammation, and fibrosis. Follow-up clinical and laboratory findings were reviewed.

RESULTS

Sixty-two cases of NGCH were identified (73% male) for analysis. The average age at liver biopsy was 2 months. Giant cell change affected on average 36% of hepatocytes (range, 5%-90%). Extramedullary hematopoiesis was common (74% of cases), often prominent, and included both myelopoiesis and erythropoiesis. Despite the term "hepatitis" in "neonatal giant cell hepatitis," portal and lobular inflammation was mild-to-absent in 95% of cases. Lobular cholestasis ranged from mild-to-moderate and demonstrated predominately a canalicular pattern (84% of cases). Bile ducts appeared hypoplastic (32% of cases) but were not absent or reduced in numbers. In contrast, another 18% of cases showed at least mild focal ductular proliferation. Portal or pericellular fibrosis was present in 30% of cases and was advanced in 8%. Subsequent clinical follow-up identified the following etiologies: Idiopathic (49%), hypopituitarism (16%), biliary atresia (8%), Alagille syndrome (6%), bile salt defects (6%), as well as several other entities present at 5% or less. Of note, the biopsy findings did not readily distinguish between the different etiologies with the exception that bile duct hypoplasia was more common in cases of hypopituitarism.

CONCLUSIONS

In this series of cases, pan-hypopituitarism was the most common recognizable clinical association with neonatal giant cell hepatitis. However, most cases of neonatal giant cell hepatitis remain idiopathic and histological features do not readily distinguish among the various etiologies.

Dose Adjustments of Hydrocortisone and L-thyroxine in Hypopituitarism Associated with Cholestasis

A patient with congenital hypopituitarism associated with cholestasis is reported here. Large doses of fat-soluble hormones (hydrocortisone (20 mg/m²/day) and L-thyroxine (14 μg/kg/day)) were needed to resolve hypoglycemia and hypothyroidism during cholestasis. The doses could be reduced to 10 mg/m²/day and 3.5 μg/kg/day, respectively, after improvement of cholestasis. Sodium valproate, which is a water-soluble drug, did not need any dose adjustments during cholestasis. Adjustment of fat-soluble hormone doses during cholestasis should be considered in patients with cholestasis.

Congenital adenohypophysis aplasia: clinical features and analysis of the transcriptional factors for embryonic pituitary development

Anterior pituitary agenesis (APA) has very rarely been reported. Therefore, its phenotypical and genotypical features are not well known. The aim of this study was to ascertain whether the clinical picture in 4 subjects with APA and multiple pituitary hormone deficiencies (MPHD) was different compared to the one observed in a selected control group consisting of 7 MPHD individuals with hypoplastic (and not aplastic) adenohypophysis and pituitary stalk interruption syndrome. Another goal was to investigate genetic basis of APA by analyzing for the first time in this condition many of the transcriptional factors which are required for both structural development and cellular differentiation of hypophysis. Age at diagnosis was significantly lower in APA children than in controls (1.5+/-2.3 vs 11.1+/-7.6 yr, p<0.0005). Microphallus and neonatal cholestasis were observed only in APA subjects (chi-squared=4.3, p<0.05) and also neonatal hypoglycemia was more frequent in APA patients than in controls (X2=4.05, p<0.05). Molecular analyses of the genes of the transcriptional factors POU1F1, PROP1, LHX3, LHX4, ISL1 and HESX1 detected no mutations in APA patients.

CONCLUSIONS

a) if compared with a selected cohort of MPHD patients with both adenohypophysis hypoplasia and pituitary stalk interruption syndrome, the ones with APA show an earlier and more severe picture of hypopituitarism; b) mutations in several transcription factors that are known to be essential for the development of Rathke's pouch are not necessarily found in humans with APA.

Guideline for the evaluation of cholestatic jaundice in infants: recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition

For the primary care provider, cholestatic jaundice in infancy, defined as jaundice caused by an elevated conjugated bilirubin, is an uncommon but potentially serious problem that indicates hepatobiliary dysfunction. Early detection of cholestatic jaundice by the primary care physician and timely, accurate diagnosis by the pediatric gastroenterologist are important for successful treatment and a favorable prognosis. The Cholestasis Guideline Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition has formulated a clinical practice guideline for the diagnostic evaluation of cholestatic jaundice in the infant. The Cholestasis Guideline Committee, consisting of a primary care pediatrician, a clinical epidemiologist (who also practices primary care pediatrics), and five pediatric gastroenterologists, based its recommendations on a comprehensive and systematic review of the medical literature integrated with expert opinion. Consensus was achieved through the Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests commonly used for the evaluation of cholestatic jaundice and how those interventions can be applied to clinical situations in the infant. The guideline provides recommendations for management by the primary care provider, indications for consultation by a pediatric gastroenterologist, and recommendations for management by the pediatric gastroenterologist. The Cholestasis Guideline Committee recommends that any infant noted to be jaundiced at 2 weeks of age be evaluated for cholestasis with measurement of total and direct serum bilirubin. However, breast-fed infants who can be reliably monitored and who have an otherwise normal history (no dark urine or light stools) and physical examination may be asked to return at 3 weeks of age and, if jaundice persists, have measurement of total and direct serum bilirubin at that time. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition on the evaluation of cholestatic jaundice in infants. The American Academy of Pediatrics has also endorsed these recommendations. These recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the care of all patients with this problem.

Common diagnostic problems in pediatric liver pathology

The role of the pathologist in dealing with common problems of liver disease in children is likely to change dramatically as the molecular genetic revolution progresses. For example, microchip arrays for genes involved in bile salt synthesis and transport will pinpoint the specific mutations responsible for infantile cholestasis and similar methods will sort out infectious agents of acute and chronic hepatitis. But even as biochemistry, microbiology, and immunology laboratories already provide essential diagnostic information in such settings, informed histopathologic interpretation will continue to guide investigations of etiology and therapeutics and will remain an important medical necessity [95,96,100,102,104].

Update on the etiologies and management of neonatal cholestasis

The early detection of cholestatic liver disease is one of the major challenges facing pediatricians when evaluating the jaundiced infant. Early recognition of liver disease greatly facilitates the care and outcome of infants, because several serious life-threatening disorders may have cholestasis as a major presenting sign of underlying neonatal liver disease. A key component of the work-up is measurement of serum conjugated bilirubin levels, which if elevated should prompt the clinician to initiate a work-up to determine the cause of neonatal cholestasis. In general, if a patient is developing progressive jaundice soon after birth, is still jaundiced at 2 weeks of life, or develops jaundice within the first month of life, a work-up for neonatal cholestasis should begin. A number of previously undiagnosed causes of neonatal cholestasis are beginning to be assigned genetic and infectious etiologies, with significant implications for the work-up and management of cholestatic infants.

The changing pattern of diagnosis of infantile cholestasis

OBJECTIVE

Cholestatic liver disease in infancy is caused by a wide range of conditions. This study reviews the pattern of diagnosis of infants with cholestasis presenting to a tertiary referral paediatric hospital in Sydney, Australia, during a 12-year period (1985-96).

METHODOLOGY

Infants aged less than 6 months with cholestasis were identified retrospectively from hospital records and data retrieved from the medical records.

RESULTS

There were 205 infants identified as having cholestatic liver disease. The aetiology of the cholestasis was idiopathic in 25%, metabolic/genetic in 23%, and due to obstruction in 20%, parenteral nutrition in 20%, infection in 9% and bile duct hypoplasia in 3%.

CONCLUSIONS

This study highlights the changing patterns of diagnosis of cholestatic liver disease in infants at a tertiary paediatric facility, demonstrating that up to 50% of cases are now due to genetic/metabolic diseases or parenteral nutrition, and a high proportion are due to idiopathic disease.

Implications of proopiomelanocortin (POMC) mutations in humans: the POMC deficiency syndrome

The recent discovery of the contribution of proopiomelanocortin (POMC)-derived peptides to the regulation of energy homeostasis and exocrine gland secretion in mice aroused new interest in the complex function of the endocrine POMC network. In addition, the first mutations in the gene encoding POMC have been identified in two patients affected by adrenal insufficiency, early onset severe obesity and red hair pigmentation. Therefore, the focus of this brief review will be the detailed discussion of the implications of these new findings in the physiology of the human POMC ligand-receptor system.