Classification and genetic features of neonatal haemochromatosis: a study of 27 affected pedigrees and molecular analysis of genes implicated in iron metabolism

Hunting for the elusive target antigen in gestational alloimmune liver disease (GALD)

The prevailing concept is that gestational alloimmune liver disease (GALD) is caused by maternal antibodies targeting a currently unknown antigen on the liver of the fetus. This leads to deposition of complement on the fetal hepatocytes and death of the fetal hepatocytes and extensive liver injury. In many cases, the newborn dies. In subsequent pregnancies early treatment of the woman with intravenous immunoglobulin can be instituted, and the prognosis for the fetus will be excellent. Without treatment the prognosis can be severe. Crucial improvements of diagnosis require identification of the target antigen. For this identification, this work was based on two hypotheses: 1. The GALD antigen is exclusively expressed in the fetal liver during normal fetal life in all pregnancies; 2. The GALD antigen is an alloantigen expressed in the fetal liver with the woman being homozygous for the minor allele and the father being, most frequently, homozygous for the major allele. We used three different experimental approaches to identify the liver target antigen of maternal antibodies from women who had given birth to a baby with the clinical GALD diagnosis: 1. Immunoprecipitation of antigens from either a human liver cell line or human fetal livers by immunoprecipitation with maternal antibodies followed by mass spectrometry analysis of captured antigens; 2. Construction of a cDNA expression library from human fetal liver mRNA and screening about 1.3 million recombinants in Escherichia coli using antibodies from mothers of babies diagnosed with GALD; 3. Exome/genome sequencing of DNA from 26 presumably unrelated women who had previously given birth to a child with GALD with husband controls and supplementary HLA typing. In conclusion, using the three experimental approaches we did not identify the GALD target antigen and the exome/genome sequencing results did not support the hypothesis that the GALD antigen is an alloantigen, but the results do not yield basis for excluding that the antigen is exclusively expressed during fetal life., which is the hypothesis we favor.

Premature birth associated with a favorable course in gestational alloimmune liver disease (GALD): A case report

Gestational alloimmune liver disease (GALD) is a rare neonatal disorder with high mortality and morbidity. The patients come to caregivers' attention aged a few hours or days. The disease manifests as acute liver failure with or without siderosis. The differential diagnosis of neonatal acute liver failure (NALF) is broad, including mainly immunologic, infectious, metabolic and toxic disorders. The most common cause, however, is GALD followed by herpes simplex virus (HSV) infection. The best suited pathophysiological paradigm of GALD is that of a maternofetal alloimmune disorder. State of the art treatment combines intravenously administered immunoglobulin (IVIG) with exchange transfusion (ET). We report an infant born at 35 + 2 weeks' gestation in whom GALD had a favorable course, of interest because premature birth in our patient may have exerted protective aspects and lessened morbidity in that intrauterine exposure to maternal complement-fixing antibodies was shortened. The diagnosis of GALD was challenging and difficult. We suggest a modified diagnostic algorithm combining clinical findings with histopathologic findings in liver and lip mucosa and, if available, on abdominal magnetic resonance imaging-study focusing on the liver, spleen, and pancreas. This diagnostic workup must be followed by ET and subsequent administration of IVIG without delay.

Chelation therapy in liver diseases of childhood: Current status and response

Chelation is the mainstay of therapy in certain pediatric liver diseases. Copper and iron related disorders require chelation. Wilson’s disease (WD), one of the common causes of cirrhosis in children is treated primarily with copper chelating agents like D-penicillamine and trientine. D-Penicillamine though widely used due its high efficacy in hepatic WD is fraught with frequent adverse effects resulting discontinuation. Trientine, an alternative drug has comparable efficacy in hepatic WD but has lower frequency of adverse effects. The role of ammonium tetra-thiomolybdate is presently experimental in hepatic WD. Indian childhood cirrhosis is related to excessive copper ingestion, rarely seen in present era. D-Penicillamine is effective in the early part of this disease with reversal of clinical status. Iron chelators are commonly used in secondary hemochromatosis of liver in hemolytic anemias. There are strict chelation protocols during bone marrow transplant. The role of iron chelation in neonatal hemochromatosis is presently not in vogue due to its poor efficacy and availability of other modalities of therapy. Hereditary hemochromatosis is rare in children and the use of iron chelators in this condition is limited.

Impact of ferumoxytol magnetic resonance imaging on the rhesus macaque maternal-fetal interface†

Ferumoxytol is a superparamagnetic iron oxide nanoparticle used off-label as an intravascular magnetic resonance imaging (MRI) contrast agent. Additionally, ferumoxytol-uptake by macrophages facilitates detection of inflammatory sites by MRI through ferumoxytol-induced image contrast changes. Therefore, ferumoxytol-enhanced MRI holds great potential for assessing vascular function and inflammatory response, critical to determine placental health in pregnancy. This study sought to assess the fetoplacental unit and selected maternal tissues, pregnancy outcomes, and fetal well-being after ferumoxytol administration. In initial developmental studies, seven pregnant rhesus macaques were imaged with or without ferumoxytol administration. Pregnancies went to term with vaginal delivery and infants showed normal growth rates compared to control animals born the same year that did not undergo MRI. To determine the impact of ferumoxytol on the maternal-fetal interface (MFI), fetal well-being, and pregnancy outcome, four pregnant rhesus macaques at ~100 gestational day underwent MRI before and after ferumoxytol administration. Collection of the fetoplacental unit and selected maternal tissues was performed 2-3 days following ferumoxytol administration. A control group that did not receive ferumoxytol or MRI was used for comparison. Iron levels in fetal and MFI tissues did not differ between groups, and there was no significant difference in tissue histopathology with or without exposure to ferumoxytol, and no effect on placental hormone secretion. Together, these results suggest that the use of ferumoxytol and MRI in pregnant rhesus macaques does not negatively impact the MFI and can be a valuable experimental tool in research with this important animal model.

PIGA Mutations Can Mimic Neonatal Hemochromatosis

Neonatal hemochromatosis (NH), one of the most common causes of liver failure in the neonate, often causes fetal loss or death during the neonatal period. Most cases are thought to be due to gestational alloimmune disease; however, other rare causes have been reported. NH is generally considered congenital and familial but not heritable. We present an infant diagnosed with NH whose clinical course differed significantly from that of most NH cases: at 11 months of age he had normal levels of liver enzymes, ferritin, and bilirubin, and normal neurodevelopment. This term male infant was born with a history of intrauterine growth restriction, oligohydramnios, and pericardial effusion. On day of life 1, he had hyperbilirubinemia and transaminitis; on day of life 3, ferritin was elevated; and on day of life 9, an MRI revealed iron deposits in the liver and renal cortex. Phenotypic features prompted a genetics consult. Whole-exome sequencing revealed a variant in the phosphatidylinositol glycan biosynthesis class A protein (PIGA) gene. Germ-line PIGA mutations are generally thought to be lethal in utero; however, there are reports of infants with PIGA mutations associated with dysmorphic features, neurologic manifestations, biochemical perturbations, and systemic iron overload; development can be normal up to 6 months of age. Because of the differences between infants with NH versus PIGA germ-line mutations in inheritance, prognosis, and natural history of disease, we propose that PIGA gene testing should be considered when evaluating newborns who present with NH.

Broadening the spectrum of neonatal hemochromatosis

Neonatal hemochromatosis (NH) has been defined as neonatal liver disorder accompanied by extrahepatic siderosis, and gestational alloimmune liver disease (GALD) is the main cause of NH. We report an atypical case of NH that may have gone underdiagnosed. A male infant was born at term after an uneventful antenatal period. At 7 h of life, he was noted to be tachypneic. Chest X-ray was normal and capillary blood gas analysis showed severe lactic acidosis. An extended blood test showed elevated levels of tyrosine and methionine that, after excluding an inborn error of metabolism, led to the diagnosis of acute liver failure. Hyperferritinemia and elevated transferrin saturation were suggestive of NH. Extrahepatic siderosis on MRI confirmed the diagnosis of NH, so even though the infant was in good general condition, a dose of intravenous immunoglobulin was administered and double volume exchange transfusion was performed. Treatment of a suspected case of GALD and prevention in subsequent gestations is imperative.

The Japanese experience and pharmacokinetics of antenatal maternal high-dose immunoglobulin treatment as a prophylaxis for neonatal hemochromatosis in siblings

Background: Neonatal hemochromatosis (NH) is a rare but serious disease causing fulminant hepatic failure. The recurrence rate of NH in a subsequent infant of a mother with an affected infant is 70-90%. Recently, antenatal maternal high-dose intravenous immunoglobulin (IVIG) treatment has been reported to be effective for preventing NH recurrence. However, data on the IgG concentrations during this treatment are limited.Objective: We report a Japanese experience and present a pharmacokinetic simulation model of IgG during IVIG treatment.Methods: Women with histories of pregnancy diagnosed with NH were treated with IVIG weekly from the second trimester until the end of gestation. Serum IgG levels during treatment were collected frequently and pharmacokinetics were simulated by a two-compartment model.Results: Six women were included during eight pregnancies. None experienced severe adverse events. Three out of eight infants showed temporary liver dysfunction, but none required any treatment. A simulation study showed that the estimated trough and peak levels of IgG concentrations during IVIG were 2000-3000 and 4000-5000 mg/dl, respectively.Conclusion: This treatment prevented the recurrence of NH in siblings in Japanese women. We examined the details of serum IgG concentrations and introduced a new pharmacokinetic simulation model of IgG concentrations during IVIG treatment.

The Effects of Gestational Alloimmune Liver Disease on Fetal and Infant Morbidity and Mortality

OBJECTIVES

To evaluate pregnancy outcomes in pedigrees of neonatal hemochromatosis to determine the spectrum of gestational alloimmune liver disease (GALD) in a large cohort.

STUDY DESIGN

We prospectively collected data from women with a prior offspring with proven neonatal hemochromatosis between 1997 and 2015 and analyzed pregnancy outcomes.

RESULTS

The pedigrees from 150 women included 350 gestations with outcomes potentially related to GALD. There were 105 live-born infants without liver disease, 157 live-born infants with liver failure, and 88 fetal losses. Fetal loss occurred in 25% of total gestations. Ninety-seven pedigrees contained a single affected offspring, whereas 53 contained multiple affected offspring. Analysis of these 53 pedigrees yielded a per-pregnancy repeat occurrence rate of 95%. Notably, the first poor outcome occurred in the first pregnancy in 60% of pedigrees. Outcomes of the 157 live-born infants with liver failure were poor: 18% survived, 82% died. Of the 134 live-born infants with treatment data, 20 received intravenous immunoglobulin with or without double-volume exchange transfusion of which 9 (45%) survived; 14 infants (10%) received a liver transplant of which 6 (43%) survived.

CONCLUSIONS

GALD is a significant cause of both fetal loss and neonatal mortality with a high rate of disease recurrence in untreated pregnancies at risk. Poor outcomes related to GALD commonly occur in the first gestation, necessitating a high index of suspicion to diagnose this disorder at first presentation.

Magnetic Resonance Imaging Findings in Neonatal Hemochromatosis

BACKGROUND

There are limited data on utility of magnetic resonance imaging (MRI) in the assessment of suspected neonatal hemochromatosis (NH).

OBJECTIVES

The aim of the study was to present our experience with utilization of multi-echo sequence MRI technique in the evaluation of NH and to compare MRI findings in infants with and without NH.

METHODS

MRI performed for suspected NH were retrospectively reviewed to note the presence and severity of iron deposition (ID) in liver, spleen, pancreas, and kidneys on multi-echo sequences. Findings were compared in infants with and without NH.

RESULTS

Of 20 infants (9 boys and 11 girls; median age of 12.5 days) included in the study, 7 of 20 had NH and 13 of 20 were assigned to the non-NH group. Higher degree of pancreatic ID was seen in the NH group (P = 0.001) with 4 of 7 evaluable pancreas showing moderate-to-severe degree and 1 of 7 showing mild degree of ID whereas none of the 13 infants in non-NH group showed moderate or severe degree of pancreatic ID. Even though the severity of hepatic ID was higher in NH group (P = 0.033), variable severity of hepatic ID was seen in both groups with most infants in both groups showing moderate-to-severe degree of ID. The severity of splenic ID was not particularly associated with any group (P = 0.774) but there was no moderate or severe degree of ID in NH. Renal ID was seen in two infants in non-NH group.

CONCLUSIONS

A moderate-to-severe degree of pancreatic ID seen on MRI tends to be associated with NH and should be sought to establish a timely diagnosis of NH. Presence and severity of hepatic ID cannot be used for differentiation of NH from other causes of neonatal liver failure.

Transient neonatal liver disease after maternal antenatal intravenous Ig infusions in gestational alloimmune liver disease associated with neonatal haemochromatosis

OBJECTIVES

Neonatal haemochromatosis is a rare gestational disease that results in severe foetal liver disease with extrahepatic iron overload, sparing the reticuloendothelial system. Recurrence can be prevented with intravenous immunoglobulin (IVIG) infusions during pregnancy, supporting an alloimmune aetiology. The aim of the study was to assess the effect of antenatal treatment with IVIG infusion on the outcome of pregnancies in women with a history of documented neonatal haemochromatosis likely owing to gestational alloimmune disease and to analyse IVIG tolerance.

METHODS

From 2004 to 2012, 8 pregnant women were treated with IVIG at 1 g/kg body weight weekly from 18 weeks' gestation until birth in a prospective multicentre study.

RESULTS

All 8 neonates born to the treated women survived. Five developed mild neonatal liver disease with hepatomegaly (n = 1), hyperechogenic liver (n = 2), abnormal liver function tests (n = 1), raised serum ferritin (n = 3) and α-fetoprotein (n = 5) levels, or mild iron overload on liver magnetic resonance imaging (n = 1). Ferritin and α-fetoprotein levels normalised before 14 days and 2 months, respectively. A per-mother-basis analysis comparing outcomes of treated (n = 8) and untreated (n = 9) gestations showed a significant improvement in the survival of neonates with gestational IVIG therapy (survival 8/8 vs 0/9, P < 0.001). Adverse effects of IVIG infusion occurred in 5 mothers leading to discontinuation of treatment in 1 case. Preterm neonates born before 37 weeks' gestation had a decreased risk of neonatal liver disease (P = 0.04).

CONCLUSIONS

Antenatal treatment with IVIG infusion in women at risk for gestational alloimmune disease recurrence improves the outcome of pregnancies despite mild signs of transient neonatal liver disease.

Clinical and Imaging Resolution of Neonatal Hemochromatosis following Treatment

Neonatal hemochromatosis (NH) is an acute liver disease associated with both hepatic and extrahepatic iron deposition and is a leading cause of neonatal liver transplantation. The concept that NH is an alloimmune disease has led to the emergence of a new treatment approach utilizing exchange transfusion and intravenous immunoglobulin therapy. We present a two-day old neonate with progressive liver dysfunction who was diagnosed with NH. Magnetic resonance imaging confirmed tissue iron overload. Treatment with intravenous immunoglobulins and exchange transfusion led to rapid improvement in liver function. Follow-up physical examination at the age of 8 months showed normal development and near normal liver function. A repeat abdominal magnetic resonance scan at 8 months showed no signs of iron deposition in the liver, pancreas, or adrenal glands. The present report provides further support for the use of exchange transfusion and immunoglobulin therapy in NH and is the first to document resolution of typical iron deposition by magnetic resonance imaging.

Neonatal hemochromatosis

Neonatal hemochromatosis is a clinical condition in which severe liver disease in the newborn is accompanied by extrahepatic siderosis. Gestational alloimmune liver disease (GALD) has been established as the cause of fetal liver injury resulting in nearly all cases of NH. In GALD, a women is exposed to a fetal antigen that she does not recognize as "self" and subsequently begins to produce IgG antibodies that are directed against fetal hepatocytes. These antibodies bind to fetal liver antigen and activate the terminal complement cascade resulting in hepatocyte injury and death. GALD can cause congenital cirrhosis or acute liver failure with and without iron overload and siderosis. Practitioners should consider GALD in cases of fetal demise, stillbirth, and neonatal acute liver failure. Identification of infants with GALD is important as treatment is available and effective for subsequent pregnancies.

Primary biliary cirrhosis-specific antimitochondrial antibodies in neonatal haemochromatosis

Background and Aim. Neonatal hemochromatosis (NH) is characterised by severe liver injury and extrahepatic siderosis sparing the reticuloendothelial system. Its aetiology is obscure, although it has been proposed as an alloimmune disease, resulting from immunological reaction to self-antigens (alloantigens) which the body recognizes as foreign. We studied an infant with NH and his mother whose sera contained antimitochondrial antibody (AMA), the hallmark of primary biliary cirrhosis (PBC). Material and Methods. To investigate the origin of AMA in the infant, we studied isotype distributions in serum from the mother and infant. Serum samples were obtained at diagnosis of NH, after liver transplantation (LT; age 1 month), and over the ensuing 17 months. Results. At NH diagnosis, infant and maternal serum contained AMA of the IgG isotype, predominantly of the G3 and G1 subclasses. AMA strongly reacted against the pyruvate dehydrogenase complex E2 subunit (PDC-E2), the major PBC-specific AMA autoantigen. Anti-PDC-E2 responses in both infant and mother declined over time, being present 2 months after LT (mother and child) and absent 10 months later (mother) and 17 months later (child). Conclusion. The association of maternally transferred IgG1 and IgG3 subclass AMA with the appearance of liver damage in an infant with NH may suggest a causal link between antibody and liver damage.

French retrospective multicentric study of neonatal hemochromatosis: importance of autopsy and autoimmune maternal manifestations

Neonatal hemochromatosis is a rare disease that causes fetal loss and neonatal death in the 1st weeks of life and is one of the most common causes of liver failure in the neonate. The diagnosis is mostly made retrospectively, based on histopathologic features of severe liver fibrosis associated with hepatic and extrahepatic siderosis. Several etiologies may underlie this phenotype, including a recently hypothesized gestational alloimmune disease. Fifty-one cases of liver failure with intrahepatic siderosis in fetuses and neonates were analyzed retrospectively. Maternal and infant data were collected from hospitalization and autopsy reports. All available slides were reviewed independently by 3 pathologists. Immunologic studies were performed on maternal sera collected immediately after delivery. The diagnosis of neonatal haemochromatosis was retained in 33 cases, including 1 case with Down syndrome and 1 case with myofibromas. Liver siderosis was inversely proportional to fibrosis progression. In fetuses, iron storage was more frequent in the thyroid than in the pancreas. Perls staining in labial salivary glands was positive in 1 of 5 cases. Abnormal low signal intensity by magnetic resonance imaging was detected in the pancreas in 2 of 7 cases. Renal tubular dysgenesis was observed in 7 of 23 autopsy cases. Chronic villitis was seen in 7 of 15 placentas. Half of the mothers presented with an autoimmune background and/or autoantibodies in their sera. Our work highlights the importance of autopsy in cases of neonatal hemochromatosis and marshals additional data in support of the hypothesis that neonatal hemochromatosis could reflect maternal immune system dysregulation.

[Prenatal treatment of neonatal hemochromatosis with maternal administration of intravenous immunoglobulins (about four cases)]

OBJECTIVES

Neonatal hemochromatosis is a very bad prognosis disease; liver transplantation was the only way to avoid an unfavourable evolution. Nowadays, hypothesis of an alloimmune mechanism for this disease has purposed to administrate high doses of immunoglobulins.

PATIENTS AND METHODS

In this study, we report four cases of women whose previous child had neonatal hemochromatosis and who received such a treatment during the next pregnancy from 18 weeks to the term.

RESULTS

This treatment allowed to lead their pregnancy to success. At birth, all four neonates were alive. Two of them presented transitory biologic symptoms of liver deficiency. All had a favourable evolution later.

DISCUSSION AND CONCLUSION

Maternal treatment with high doses of immunoglobulins during pregnancy seems to improve dramatically the prognosis of neonatal hemochromatosis as it has been already reported. It could also apply to other diseases, which proceed from the same mechanism.

Deoxyguanosine kinase deficiency presenting as neonatal hemochromatosis

Mutations in DGUOK result in mitochondrial DNA (mtDNA) depletion and may present as neonatal liver failure. Neonatal hemochromatosis (NH(1)) is a liver disorder of uncertain and varied etiology characterized by hepatic and non-reticuloendothelial siderosis. To date, deoxyguanosine kinase (dGK(2)) deficiency has not been formally recognized in cases of NH. We report an African American female neonate with clinical and autopsy findings consistent with NH, and mtDNA depletion due to a homozygous mutation in DGUOK. This report highlights hepatocerebral mtDNA depletion in the differential of neonatal tyrosinemia, advocates considering dGK deficiency in cases of NH, and posits mitochondrial oxidative processes in the pathogenesis of NH.

Therapeutic management of neonatal hemochromatosis: Report of four cases and literature review

Neonatal hemochromatosis (NH) is a rare disease of iron metabolism that starts at intrauterine period causing liver failure and extrahepatic siderozis. The etiology of NH has not been understood exactly, yet it is accepted that a maternofetal alloimmune disorder that leads to liver failure in fetus causes the illness. The prognosis of NH is generally bad and death is inevitable if left untreated. The efficiency of chelation–antioxidant coctail used in medical treatment is between 10% and 20% and these patients frequently need liver transplantation. In our study, we presented four newborn cases diagnosed as NH and treated medically. Of the four patients, one died of pulmonary hemorrhage and another died of multiorgan failure in the first week of hospitalization. The other two patients' clinical status and laboratory parameters recovered with medical treatment. However, since liver transplantation was not carried out, one of these patients died at the age of two and a half months and the other at eighth month due to sepsis. In this study, we would like to emphasize the importance of early liver transplantation in patients recovered with medical treatment.

Clinicopathologic conference: multiple fetal demises, lactic acidosis and hepatic iron accumulation

A case of a premature infant with lactic acidosis and hepatic iron accumulation, born to a mother with multiple fetal demises, is presented and discussed by both clinician and pathologist, in this traditional clinico-pathologic conference. The discussion includes the differential diagnoses of lactic acidosis and hepatic iron accumulation in infants.

Novel mechanism of fetal hepatocyte injury in congenital alloimmune hepatitis involves the terminal complement cascade

Evidence suggests that most neonatal hemochromatosis (NH) is the phenotypic expression of gestational alloimmune fetal liver injury. Gestational alloimmune diseases are induced by the placental passage of specific reactive immunoglobulin G and often involve the activation of fetal complement by the classical pathway leading to the formation of membrane attack complex (MAC) as the effector of cell injury. We examined liver specimens from cases of NH, from cases of non-NH liver disease, and from infants without liver disease to determine if they would provide evidence that MAC is involved in hepatocyte injury. Sections were immunostained with anti-human C5b-9 complex, the terminal complement cascade (TCC) neoantigen formed in the assembly of MAC. Fetal liver injury in NH cases is associated with a severe loss of hepatocytes. In all NH cases examined, most remaining hepatocytes showed intense staining for TCC neoantigen, whereas hepatocytes in non-NH liver disease cases showed variable light staining. The percentage of hepatocytes containing TCC neoantigen in NH was much greater than that in non-NH liver disease, and there was no overlap between the groups. Findings in both groups suggest that hepatocytes have mechanisms to protect against MAC, including a biliary pathway for its excretion.

CONCLUSION

The finding that all cases of proven NH contained TCC neoantigen far in excess of cases of other neonatal liver diseases suggests that a single process, namely congenital alloimmune hepatitis, is the principal cause of NH. MAC-mediated alloimmune injury in congenital alloimmune hepatitis is a novel mechanism of liver injury that results from an interplay of maternal adaptive immunity and fetal innate immunity.

A case report of neonatal diabetes due to neonatal hemochromatosis

A 6-week-old girl, the first child of non-consanguineous parents, was admitted to the hospital for evaluation of vomiting. She was small for gestational age (1500 g). On admission, she weighed 1830 g, and appeared dehydrated. The blood glucose was 880 mg/dL. Insulin and C-peptide levels were <1 microIU/ml and 0.1 pmol/L, respectively. Antibodies of diabetes were negative. The serum triglyceride level was markedly elevated (5322 mg/dL). After a few days of insulin therapy, the triglyceride levels dramatically decreased, but cholestasis persisted. A liver biopsy revealed diffuse iron deposition and the diagnosis of neonatal hemochromatosis was established. In neonatal hemochromatosis, diabetes may occur as a result of iron deposition in the pancreas. The coexistence of neonatal diabetes secondary to neonatal hemochromatosis with a fatal course during the infancy period has not been previously reported. In this report, an infant with neonatal diabetes secondary to neonatal hemochromatosis is presented as the first case in the literature involving the coexistence of these two conditions.

Neonatal hemochromatosis and Martinez-Frias syndrome of intestinal atresia and diabetes mellitus in a consanguineous newborn

Neonatal hemochromatosis is a heterogeneous disorder of iron metabolism characterized by hepatic failure and marked iron accumulation in liver and extrahepatic tissues. Autosomal recessive transmission is found in most cases. Neonatal hemochromatosis shares cellular features with the adult disease but is clinically and genetically distinct, the causal gene(s) being presently unknown. We report on a newborn from consanguineous parents who presented with multiple congenital anomalies and neonatal hemochromatosis. The syndrome consisted of intra-uterine growth retardation, intestinal atresia, gallbladder aplasia and diabetes mellitus, and fitted with the diagnosis of Martinez-Frias syndrome, a very rare autosomal recessive phenotype, the gene of which remains to be identified. We suggest that neonatal hemochromatosis may be part of the Martinez-Frias syndrome. Molecular analyses in this and other reported patients with the Martinez-Frias syndrome should shed light on gut development and iron metabolism.

Treatment of neonatal hemochromatosis with exchange transfusion and intravenous immunoglobulin

OBJECTIVE

To determine if immunomodulatory treatment including intravenous immunoglobulin (IVIG) can favorably affect survival in neontatal hemochromatosis (NH) diagnosed postnatally because it can effectively prevent occurrence of NH when applied during gestations at risk.

STUDY DESIGN

We treated 16 newborn infants with liver failure due to NH with high-dose IVIG, in combination with exchange transfusion in 13 (ET/IVIG), and compared the outcome with 131 historical controls treated conventionally.

RESULTS

The severity of liver disease as estimated by prothrombin time was similar in the subjects receiving ET/IVIG and the historical controls, and the medical therapy was equivalent with the exception of the ET/IVIG therapy. Twelve subjects (75%) had good outcome, defined as survival without liver transplantation, whereas good outcome was achieved in only 17% (23/131) of historical control patients (P < .001). Four subjects died, 2 without and 2 after liver transplant. Survivors were discharged 6 to 90 days after receiving ET/IVIG therapy, and those followed for more than 1 year are within normal measures for growth, development, and liver function.

CONCLUSIONS

Immune therapy with ET/IVIG appears to improve the outcome and reduce the need for liver transplantation in patients with NH.

Neonatal hemochromatosis: a case report

Neonatal hemochromatosis is a rare disease of iron metabolism, characterized by the excess accumulation of iron in the tissues. This occurs in utero and can lead to fetal demise or an infant who presents with advanced liver disease in the neonatal period. A case of neonatal hemochromatosis is reported in a 37-week infant who presented at birth with thrombocytopenia, coagulopathy, and abnormal liver imaging studies. The diagnoses of infection and metabolic errors were excluded before the confirmation of neonatal hemochromatosis was made. This diagnosis was confirmed by elevated ferritin levels and extrahepatic siderosis excluding the reticuloendothelial system. Anti-oxidant therapy was initiated with N-acetyl cysteine, selenium, vitamins C and E and intravenous immunoglobulin. The infant demonstrated a positive response and was discharged home with outpatient follow up. The clinical presentation of neonatal hemochromatosis is reviewed as well as diagnosis and treatment strategies.

Outcome of pregnancies at risk for neonatal hemochromatosis is improved by treatment with high-dose intravenous immunoglobulin

OBJECTIVES

Neonatal hemochromatosis is the result of severe fetal liver injury that seems to result from maternal-fetal alloimmunity. Women who have had an infant affected with neonatal hemochromatosis are at high risk in subsequent pregnancies for having another affected infant. This study was designed to determine whether therapy directed at limiting the severity of gestational alloimmunity can reduce the occurrence of severe neonatal hemochromatosis in infants of women at risk. A secondary objective was to use a prospectively collected data set to examine questions of vital interest about neonatal hemochromatosis.

METHODS

Women with a history of pregnancy ending in documented neonatal hemochromatosis were treated with intravenous immunoglobulin at 1 g/kg of body weight weekly from week 18 until the end of gestation. Extensive data were prospectively collected regarding the gestational histories of the subjects. The outcomes of treated pregnancies were compared with those of previous affected pregnancies, which were used as historical controls.

RESULTS

Forty-eight women were enrolled to be treated during 53 pregnancies. The gestational histories of these women demonstrated the high risk of occurrence of neonatal hemochromatosis: 92% of pregnancies at risk resulted in intrauterine fetal demise, neonatal death, or liver failure necessitating transplant. In contrast, with gestational therapy, the 53 at-risk gestations resulted in 3 failures and 52 infants who survived intact with medical therapy alone. When compared on a per-woman or per-infant basis, the outcome of gestation at risk for neonatal hemochromatosis was improved by gestational therapy.

CONCLUSIONS

Neonatal hemochromatosis seems to be the result of a gestational alloimmune disease, and occurrence of severe neonatal hemochromatosis in at-risk pregnancies can be significantly reduced by treatment with high-dose intravenous immunoglobulin during gestation.

Neonatal haemochromatosis associated with gastroschisis

We describe, to our knowledge, the first case of progressive neonatal liver failure due to neonatal haemochromatosis (NH) occurring in an infant with a gastroschisis and review the literature regarding these two conditions. A 1,665 g male infant with antenatally diagnosed gastroschisis was born with a severe coagulopathy, anaemia, thrombocytopenia, hypoglycaemia and jaundice. He developed progressive liver failure, complicated by necrotising enterocolitis. Serum ferritin was elevated at 1,459 microg/L. He died on day 40 and a limited post-mortem examination confirmed significant hepatic siderosis with fibrosis and cholestasis, and siderosis of the pancreas. Although no genetic aetiology for gastroschisis has been identified, an occasional inherited tendency has been observed. There is also evidence to support an autosomal recessive inheritance in NH.

[Cholestasis-associated hepatopathies in neonates and infants]

Cholestasis in neonates and infants frequently confronts pediatricians and pathologists with diagnostic problems. A specific feature of the liver in neonates is the ability to react to different causative factors with a non-specific hepatitis-like picture, the so-called neonatal hepatitis. A diagnostic discrimination of the various diseases is histologically only possible with close attention to typical morphologic features. Thus, extrahepatic biliary obstructions, such as atresia or stenosis of the hepatic duct or choledochal cysts present with portal bile duct proliferation and signs of bile retention in the neoducts. In Alagille syndrome (arteriohepatic dysplasia), however, paucity of intrahepatic bile ducts is an important diagnostic feature. Metabolic disorders, such as fructosemia and galactosemia are additionally associated with steatosis. Knowledge of the clinical course and laboratory and imaging data are necessary to make the definitive diagnosis in synopsis with the morphologic findings and requires a close co-operation between the pediatrician and the pathologist.

Review article: the genetic basis of haemochromatosis

BACKGROUND

Since the seminal discovery of the HFE gene a decade ago, considerable further progress in unravelling the genetic basis of haemochromatosis has been made. Novel genes and iron overload phenotypes have been described with potential insights into the molecular pathophysiology of human iron metabolism.

AIM

To review recent key advances in the field of inherited iron overload and assess their impact on clinical practice and on our understanding of iron regulation.

METHODS

A PubMed search was undertaken predominantly using 'haemochromatosis', 'HFE', 'hepcidin' and 'ferroportin'. Illustrative cases were sought.

RESULTS

The impact of HFE mutation analysis on the management of haemochromatosis is significant and allows early accurate diagnosis. HFE is also implicated in the siderosis associated with other liver pathologies. Non-HFE genes underpinning other forms of haemochromatosis are now recognized and genotype-phenotype interactions result in a spectrum of disease. These novel gene products interact with HFE in a common pathway for iron homeostasis.

CONCLUSIONS

Further identification of non-HFE genes associated with iron homeostasis will enhance our diagnostic certainty of primary haemochromatosis and may explain the variable expression seen in HFE-related disease. Improving our understanding of the mechanisms of iron regulation may lead to novel therapeutic strategies for the management of iron overload.

Traitement par immunoglobulines pendant la grossesse chez deux patientes à risque de récurrence d'hémochromatose néonatale

Two patients, with prior affected children with Neonatal Haemochromatosis [NH], benefited from intravenous immunoglobulin treatment during their following pregnancy in order to prevent recurrent NH. Whereas NH is a severe disease with high risk of recurrence and high mortality rate (about 80%), a recent treatment was suggested in the USA, which seems to completely modify the prognosis of this pathology. We proposed this treatment for two patients with indeed apparent benefit, giving birth to two healthy babies.

Of mice and men: genetic determinants of iron status

Fe homeostasis is maintained by regulation of Fe absorption to balance largely unregulated body Fe losses. The majority of human subjects maintain relatively constant Fe stores; however, Fe deficiency and Fe overload are common conditions. Fe overload is frequently associated with mutations in genes of Fe metabolism. The present paper summarises present knowledge of these mutations as well as indicating other genes that animal studies have implicated as candidates for influencing body Fe stores.

Successful pregnancy outcome following maternal intravenous immunoglobulin treatment in a woman with recurrent perinatal haemochromatosis

OBJECTIVE

We report a case of successful pregnancy outcome following maternal intravenous immunoglobulin treatment in a woman with previous history of recurrent fetal hydrops secondary to perinatal haemochromatosis.

METHODS

A 32-year old woman had two successive pregnancies complicated by fetal hydrops and perinatal deaths. Pathological examination of the fetus showed severe liver destruction with siderosis of hepatocytes at extrahepatic sites, but sparing of the reticulo-endothelial elements, consistent with the diagnosis of perinatal haemochromatosis. In the subsequent pregnancy, maternal intravenous immunoglobulin was administered weekly from the 18th week of gestation until delivery by elective caesarean section at 38 weeks. The infant was treated with desferrioxamine, N-acetylcysteine, vitamins K and E.

RESULTS

The infant was born in good health, but had high serum ferritin levels, markedly elevated percent transferrin saturation, and mild transient derangement of liver and coagulation function. The infant made an excellent recovery and the treatment was stopped at 7 weeks of age. The liver and coagulation parameters and the serum ferritin levels returned to normal values.

CONCLUSIONS

Haemochromatosis should be considered in the differential diagnosis of hydrops fetalis. The recurrence risk is high, and immunomodulation with intravenous immunoglobulin treatment appears to alter the course of the disease with better infant survival.

Iron in fetal and neonatal nutrition

Both iron deficiency and iron excess during the fetal and neonatal period bode poorly for developing organ systems. Maternal conditions such as iron deficiency, diabetes mellitus, hypertension and smoking, and preterm birth are the common causes of perinatal iron deficiency. Long-term neurodevelopmental impairments and predisposition to future iron deficiency that are prevalent in infants with perinatal iron deficiency require early diagnosis, optimal treatment and adequate follow-up of infants at risk for the condition. However, due to the potential for oxidant-mediated tissue injury, iron overload should be avoided in the perinatal period, especially in preterm infants.

Neonatal hemochromatosis: long-term experience with favorable outcome

OBJECTIVE

Neonatal hemochromatosis is a severe, often fatal multiorgan disorder of iron metabolism. Liver transplantation can be curative; the benefit of antioxidant treatment is discussed controversially. We summarize our experience with neonatal hemochromatosis over the past 13 years.

METHODS

A retrospective study was performed of 16 patients with acute liver failure attributable to neonatal hemochromatosis between 1992 and 2004.

RESULTS

Median age at the onset of neonatal hemochromatosis was 2 days (range: 0-21 days). Median weight at the time of diagnosis was 2900 g (range: 1520-4200 g). All patients had elevated ferritin levels (median: 4179 microg/L), and transferrin saturation (median: 99%). Fourteen patients (87.5%) showed significant hepatocyte siderosis in biopsies; 4 children had additional iron deposition in extrahepatic tissue. Four patients were diagnosed by MRI. Seven infants received liver transplants, 5 of them in combination with a preceding antioxidant treatment. Four children (25%) received antioxidants without the necessity of liver transplantation and were in good clinical condition at the time of this evaluation. Five patients (31.3%) died, 3 of them without any treatment because of initial fulminant multiorgan failure. In September 2005, 68.7% of the patients were still alive after a median follow-up of 5 years.

CONCLUSIONS

Neonatal hemochromatosis is a severe metabolic disease, but early antioxidant treatment and liver transplantation in addition to optimal medical care can improve the outcome dramatically. Children with moderate liver failure can survive without liver transplantation, but should be monitored closely for deterioration.

Neonatal hyperphenylalaninemia, perinatal hemochromatosis, and renal tubulopathy: a unique patient or a novel metabolic disorder?

A neonate presented with hyperphenylalaninemia (HPA), with a persistently elevated phenylalanine/tyrosine ratio. The HPA was responsive to tetrahydrobiopterin (BH4). His clinical course was dominated by liver failure, associated with perinatal hemochromatosis. He also developed renal tubulopathy. HPA has not previously been reported in association with any of these features. We investigated the etiology of his condition, and discuss the possibility that this represents a novel single-gene disorder.

Disparate clinical presentation of neonatal hemochromatosis in twins

Neonatal hemochromatosis (NH) is a rare disease of gestation that results in fetal liver injury and extrahepatic siderosis. The etiology of NH is not fully understood. However, the rate of recurrence of NH in the pregnancy after an affected one is approximately 80%. A spectrum of liver disease has been recognized, spanning from liver failure in the fetus or neonate to infants that survive with medical therapy. Here we report on 2 sets of fraternal twins, each set with a gross disparity in the severity of presentation: 1 infant with liver failure and the other nearly unaffected. These findings suggest a need to look carefully for subclinical disease in the siblings of patients with NH by using sensitive tests such as those for ferritin and alpha-fetoprotein. They also suggest that affected infants may be missed when using routine clinical testing, which would lead to the apparent rate of recurrence, understating the actual recurrence rate.

Neonatal hemochromatosis: fetal liver disease leading to liver failure in the fetus and newborn

Acute liver failure in the newborn is relatively rare but often fatal. The broadest definition of acute liver failure is failure of the vital functions of the liver occurring within weeks or a few months of the onset of clinical liver disease. Therefore, by definition, any liver failure in the newborn can be construed to be acute liver failure. A second component of the general definition of acute liver failure is the lack of known preexisting liver disease. In the case of neonatal acute liver failure, preexisting disease would by definition be liver disease that affects the fetus. Almost nothing is known about fetal onset liver failure, and there is no literature addressing the subject. This review will address fetal liver disease that leads to liver failure in the fetus or newborn.

Recent advances in understanding haemochromatosis: a transition state

Mutations in the hepcidin gene HAMP and the hemojuvelin gene HJV have recently been shown to result in juvenile haemochromatosis (JH). Hepcidin is an antimicrobial peptide that plays a key role in regulating intestinal iron absorption. Hepcidin levels are reduced in patients with haemochromatosis due to mutations in the HFE and HJV genes. Digenic inheritance of mutations in HFE and HAMP can result in either JH or hereditary haemochromatosis (HH) depending upon the severity of the mutation in HAMP. Here we review these findings and discuss how understanding the different types of haemochromatosis and our increasing knowledge of iron metabolism may help to elucidate the host's response to infection.

Inherited iron loading: genetic testing in diagnosis and management

Elucidation of the molecular pathways of iron transport through cells and its control is leading to an understanding of genetic iron loading conditions. The general phenotype of haemochromatosis is iron accumulation in liver parenchymal cells, a raised serum transferrin saturation and ferritin concentration. Four types have been identified: type 1 is the common form and is an autosomal recessive disorder of low penetrance strongly associated with mutations in the HFE gene on chromosome 6(p21.3); type 2 (juvenile haemochromatosis) is autosomal recessive, of high penetrance with causative mutations identified in the HFE2 gene on chromosome 1 (q21) and the HAMP gene on chromosome 19 (q13); type 3 is also autosomal recessive with mutations in the TfR2 gene on chromosome 3 (7q22); type 4 is an autosomal dominant condition with heterozygous mutations in the ferroportin 1 gene. In type 4, iron accumulates in both parenchymal and reticuloendothelial cells and the transferrin saturation may be normal. There are also inherited neurodegenerative conditions associated with iron accumulation. The current research challenges include understanding the central role of the HAMP gene (hepcidin) in controlling iron absorption and the reasons for the variable penetrance in HFE type 1.

Bases moléculaires des hémochromatoses génétiques

PURPOSE

Recent discoveries in molecular mechanisms of iron metabolism have changed the classical view of hereditary iron overload conditions. We present natural mutations in newly discovered genes and related phenotypes observed in patients with different form of haemochromatosis.

CURRENT KNOWLEDGE AND KEY POINTS

Most haemochromatosis patients are homozygous for the C282Y mutation in the HFE gene. Ferroportin, TFR2, hemojuvelin and hepcidin mutations also cause iron overload. Recent data support the hypothesis that haemochromatosis should no longer be considered a monogenic disease but rather an oligogenic disorder. Several results suggest that haemochromatosis could result from digenic inheritance of mutations in HFE and HAMP.

FUTURE PROSPECTS AND PROJECTS

Other modifier genes probably influence penetrance in C282Y homozygous patients. Such genes could enhance or reduce the phenotypic expression in various iron overload conditions.

Deletion of murine Smn exon 7 directed to liver leads to severe defect of liver development associated with iron overload

Spinal muscular atrophy (SMA) is characterized by degeneration of lower motor neurons caused by mutations of the survival motor neuron 1 gene (SMN1). SMN is involved in various processes including the formation of the spliceosome, pre-mRNA splicing and transcription. To know whether SMN has an essential role in all mammalian cell types or an as yet unknown specific function in the neuromuscular system, deletion of murine Smn exon 7, the most frequent mutation found among SMA patients, has been restricted to liver. Homozygous mutation results in severe impairment of liver development associated with iron overload and lack of regeneration leading to dramatic liver atrophy and late embryonic lethality of mutant mice. These data strongly suggest an ubiquitous and essential role of full-length SMN protein in various mammalian cell types. In SMA patients, the residual amount of SMN allows normal function of various organs except motor neurons. However, data from mouse and human suggest that other tissues might be involved in severe form of SMA or during prolonged disease course which reinforce the need of therapeutic approaches targeted to all tissues. In addition, liver function of patients should be carefully investigated and followed up before and during therapeutic trials.

Iron homeostasis and inherited iron overload disorders: an overview

Iron is an ubiquitous metal of vital importance to the normal physiologic processes of many organisms. Recent discoveries of mutations in genes that lead to inherited iron overload diseases have advanced the understanding of iron homeostasis in humans. This article provides an overview of the human iron cycle, regulation of iron homeostasis, how perturbations in this homeostasis lead to iron overload disease in adults and children, and strategies for diagnosis of inherited iron overload.

High-dose immunoglobulin during pregnancy for recurrent neonatal haemochromatosis

BACKGROUND

Neonatal haemochromatosis is a rare disease of gestation that results in severe fetal liver injury. We hypothesised an alloimmune aetiology for the disorder on the basis of its high recurrence rate in sibships. In this study, we assessed the effectiveness in preventing or changing the severity of recurrent neonatal haemochromatosis of administering during pregnancy high-dose intravenous immunoglobulin (IVIG) derived from pooled serum of multiple donors.

METHODS

Women whose most recent pregnancy ended in documented neonatal haemochromatosis were treated with IVIG, 1 g/kg bodyweight, weekly from the 18th week until the end of gestation in their subsequent pregnancy. The outcomes of treated pregnancies were compared with those of randomly selected previous affected pregnancies for each woman, which were used as historical controls.

FINDINGS

15 women were treated through 16 pregnancies. All pregnancies progressed uneventfully and resulted in live babies with normal physical examinations and birthweights that were appropriate for gestational age. 12 babies had evidence of liver involvement with neonatal haemochromatosis: 11 had higher than normal concentrations of serum alpha-fetoprotein and ferritin or serum alpha-fetoprotein alone, including four with coagulopathy (international normalised ratio >1.5), and one had coagulopathy alone. All babies survived with medical or no treatment and were healthy at follow-up within the past 6 months. In analysis on a per-mother basis comparing outcomes of treated gestations with those of randomly selected previous affected gestations, gestational IVIG therapy was associated with better infant survival (15 good outcomes vs two in previous pregnancies; p=0.0009).

INTERPRETATION

Treatment with high-dose IVIG during gestation appears to have modified recurrent neonatal haemochromatosis so that it was not lethal to the fetus or neonate. These results further support an alloimmune mechanism for recurrent neonatal haemochromatosis.