Severe acute liver disease in adults: Contemporary role of histopathology

Liver biopsies have consistently contributed to our understanding of the pathogenesis and aetiologies of acute liver disease. As other diagnostic modalities have been developed and refined, the role of biopsy in the management of patients with acute liver failure (ALF), acute-on-chronic liver failure (ACLF) and acute hepatitis, including acute liver injury (ALI), has changed. Liver biopsy remains particularly valuable when first-line diagnostic algorithms fail to determine aetiology. Despite not being identified as a mandatory diagnostic tool in recent clinical guidelines for the management of ALF or ACLF, many centres continue to undertake biopsies given the relative safety of transjugular biopsy in this setting. Several studies have demonstrated that liver biopsy can provide prognostic information, particularly in the context of so-called indeterminate hepatitis, and is extremely useful in excluding conditions such as metastatic tumours that would preclude transplantation. In addition, its widespread use of percutaneous biopsies in cases of less severe acute liver injury, for example in the establishment of a diagnosis of acute presentation of autoimmune hepatitis or confirmation of a probable or definite drug-induced liver injury (DILI), has meant that many centres have seen a shift in the ratio of specimens they are receiving from patients with chronic to acute liver disease. Histopathologists therefore need to be equipped to deal with these challenging specimens. This overview provides an insight into the contemporary role of biopsies (as well as explant and autopsy material) in diagnosing acute liver disease. It outlines up-to-date clinical definitions of liver injury and considers recent recommendations for the diagnosis of AIH and drug-induced, autoimmune-like hepatitis (DI-AIH).

The role of liver transplantation in the care of primary hepatic vascular tumours in children

Liver transplantation (LT) is the standard of care for many liver conditions, such as end-stage liver diseases, inherited metabolic disorders, and primary liver malignancies. In the latter group, indications of LT for hepatoblastoma and hepatocellular carcinoma evolved and are currently available for many non-resectable cases. However, selection criteria apply, as the absence of active metastases. Evidence of good long-term outcomes has validated the LT approach for managing these malignancies in the context of specialist and multidisciplinary approach. Nevertheless, LT's role in treating primary vascular tumours of the liver in children, both benign and malignant, remains somewhat controversial. The rarity of the different diseases and the heterogeneity of pathological definitions contribute to the controversy and make evaluating the benefit/risk ratio and outcomes quite difficult. In this narrative review, we give an overview of primary vascular tumours of the liver in children, the possible indications and the outcomes of LT.

Protein Misfolding and Aggregation: The Relatedness between Parkinson's Disease and Hepatic Endoplasmic Reticulum Storage Disorders

Dysfunction of cellular homeostasis can lead to misfolding of proteins thus acquiring conformations prone to polymerization into pathological aggregates. This process is associated with several disorders, including neurodegenerative diseases, such as Parkinson’s disease (PD), and endoplasmic reticulum storage disorders (ERSDs), like alpha-1-antitrypsin deficiency (AATD) and hereditary hypofibrinogenemia with hepatic storage (HHHS). Given the shared pathophysiological mechanisms involved in such conditions, it is necessary to deepen our understanding of the basic principles of misfolding and aggregation akin to these diseases which, although heterogeneous in symptomatology, present similarities that could lead to potential mutual treatments. Here, we review: (i) the pathological bases leading to misfolding and aggregation of proteins involved in PD, AATD, and HHHS: alpha-synuclein, alpha-1-antitrypsin, and fibrinogen, respectively, (ii) the evidence linking each protein aggregation to the stress mechanisms occurring in the endoplasmic reticulum (ER) of each pathology, (iii) a comparison of the mechanisms related to dysfunction of proteostasis and regulation of homeostasis between the diseases (such as the unfolded protein response and/or autophagy), (iv) and clinical perspectives regarding possible common treatments focused on improving the defensive responses to protein aggregation for diseases as different as PD, and ERSDs.

The Recruitment-Secretory Block ("R-SB") Phenomenon and Endoplasmic Reticulum Storage Diseases

In this article, we review the biological and clinical implication of the Recruitment-Secretory Block (“R-SB”) phenomenon. The phenomenon refers to the reaction of the liver with regard to protein secretion in conditions of clinical stimulation. Our basic knowledge of the process is due to the experimental work in animal models. Under basal conditions, the protein synthesis is mainly carried out by periportal (zone 1) hepatocytes that are considered the “professional” synthesizing protein cells. Under stimulation, midlobular and centrolobular (zones 2 and 3) hepatocytes, are progressively recruited according to lobular gradients and contribute to the increase of synthesis and secretion. The block of secretion, operated by exogenous agents, causes intracellular retention of all secretory proteins. The Pi MZ phenotype of Alpha-1-antitrypsin deficiency (AATD) has turned out to be the key for in vivo studies of the reaction of the liver, as synthesis and block of secretion are concomitant. Indeed, the M fraction of AAT is stimulated for synthesis and regularly exported while the Z fraction is mostly retained within the cell. For that reason, the phenomenon has been designated “Recruitment-Secretory Block” (“R-SB”). The “R-SB” phenomenon explains why: (a) the MZ individuals can correct the serum deficiency; (b) the resulting immonohistochemical and electron microscopic (EM) patterns are very peculiar and specific for the diagnosis of the Z mutation in tissue sections in the absence of genotyping; (c) the term carrier is no longer applicable for the heterozygous condition as all Pi MZ individuals undergo storage and the storage predisposes to liver damage. The storage represents the true elementary lesion and consequently reflects the phenotype-genotype correlation; (d) the site and function of the extrahepatic AAT and the relationship between intra and extracellular AAT; (e) last but not least, the concept of Endoplasmic Reticulum Storage Disease (ERSD) and of a new disease, hereditary hypofibrinogenemia with hepatic storage (HHHS). In the light of the emerging phenomenon, described in vitro, namely that M and Z AAT can form heteropolymers within hepatocytes as well as in circulation, we have reviewed the whole clinical and experimental material collected during forty years, in order to evaluate to what extent the polymerization phenomenon occurs in vivo. The paper summarizes similarities and differences between AAT and Fibrinogen as well as between the related diseases, AATD and HHHS. Indeed, fibrinogen gamma chain mutations undergo an aggregation process within the RER of hepatocytes similar to AATD. In addition, this work has clarified the intriguing phenomenon underlying a new syndrome, hereditary hypofibrinogenemia and hypo-APO-B-lipoproteinemia with hepatic storage of fibrinogen and APO-B lipoproteins. It is hoped that these studies could contribute to future research and select strategies aimed to simultaneously correct the hepatocytic storage, thus preventing the liver damage and the plasma deficiency of the two proteins.

Hepatic and Extrahepatic Sources and Manifestations in Endoplasmic Reticulum Storage Diseases

Alpha-1-antitrypsin (AAT) and fibrinogen are secretory acute phase reactant proteins. Circulating AAT and fibrinogen are synthesized exclusively in the liver. Mutations in the encoding genes result in conformational abnormalities of the two molecules that aggregate within the rough endoplasmic reticulum (RER) instead of being regularly exported. That results in AAT-deficiency (AATD) and in hereditary hypofibrinogenemia with hepatic storage (HHHS). The association of plasma deficiency and liver storage identifies a new group of pathologies: endoplasmic reticulum storage disease (ERSD).

Fifty years of impact on liver pathology: a history of the Gnomes

Professional societies play a major role in medicine and science. The societies tend to be large with well-developed administrative structures. An additional model, however, is based on small groups of experts who meet regularly in an egalitarian model in order to discuss disease-specific scientific and medical problems. In order to illustrate the effectiveness of this model, the history and practices are examined of a long-standing successful example, the International Liver Pathology Group, better known as the Gnomes. The history shows that groups such as the Gnomes offer a number of important benefits not available in larger societies and nurturing such groups advances science and medicine in meaningful ways. The success of the Gnomes' approach provides a road map for future small scientific groups.

Mineralization of alpha-1-antitrypsin inclusion bodies in Mmalton alpha-1-antitrypsin deficiency

Background

Alpha-1-antitrypsin (AAT) deficiency (AATD) of Z, Mmalton, Siiyama type is associated with liver storage of the mutant proteins and liver disease. The Z variant can be diagnosed on isoelectric focusing (IEF) while Mmalton and Siiyama may be missed or misdiagnosed with this technique. Therefore, molecular analysis is mandatory for their characterization. In particular, that holds true for the Mmalton variant as on IEF profile it resembles the wild M2 subtype.

Methods

This is a retrospective analysis involving review of medical records and of liver biopsy specimens from a series of Mmalton, Z and Siiyama Alpha-1-antitrypsin deficiency patients. The review has been implemented by additional histological stains, electron microscopic observations and 3-D modeling studies of the sites of the mutations.

Results

Z, Mmalton and Siiyama liver specimen contained characteristic intrahepatocytic PAS-D globules. The globules differed in the three variants as only Mmalton cases showed dark basophilic precipitates within the AAT inclusions. The precipitates were visualized in haematoxylin-eosin (H.E.) stained preparations and corresponded to calcium precipitates as demonstrated by von Kossa staining. On immunohistochemistry, ZAAT inclusions were stained by polyclonal as well as monoclonal noncommercial anti-AAT antibody (AZT11), whilst Mmalton and Siiyama inclusion bodies remained negative with the monoclonal anti-Z antibody. 3-D protein analysis allowed to predict more severe misfolding of the Mmalton molecule as compared to Z and Siiyama that could trigger anomalous interaction with endoplasmic reticulum chaperon proteins, namely calcium binding proteins.

Conclusions

Mmalton AAT inclusion bodies contain calcium precipitates inside them that allow the differential diagnosis with Siiyama and ZAAT inclusions in routine histological sections. The study has confirmed the specificity of the monoclonal AZT11 for the Z mutant. Thus, the combination of these two features is crucial for the distinction between the three variants and for predicting the genotype, whose confirmation would definitely require molecular analysis. Our study provides new data on the pathomorphogenesis of Mmalton inclusion bodies whose mineralization could play a central role in disease pathogenesis of Mmalton that is distinct from the Z and Siiyama variants. Calcium is known to be a major effector of cell death either via the increased intracellular concentration or the alteration of homeostasis.

Results. of a Mammographic and Clinical Screening in a Health District (USSL) of Brescia, Italy

Aims and Background

Screening by mammography has been shown to be effective in reducing breast cancer mortality. We present the results of a mammographic and clinical screening program carried out in an Italian health district.

Methods

The first screening round started in June 1987 and ended in July 1990, and 25,100 women between the age of 50 and 60 years were invited. The second screening round invited 34,332 women between the age of 50 and 64 years and was carried out from September 1990 to September 1993. Women with positive or equivocal results at palpation or mammography were referred for immediate diagnostic assessment followed by surgery, when required.

Results

The attendance rate was 67.3% at the first and 62.1% at the repeat screening. At the first screening, 206 biopsies were advised and 197 were performed; 129 of the 197 were found to be malignant. At repeat screening, 248 biopsies were recommended, 208 were performed, and 125 were found to be malignant. The cancer detection rate was 7.7 per thousand at the first and 5.9 per thousand at repeat screening. Of 129 cancers, 107 (83.0%) were T1 at first screening; 6.2% were in situ carcinomas. Axillary lymph nodes were histologically positive in 24% of cases. At repeat screening, 77.6% (97/125) of cancers were T1; 11.2% were in situ carcinomas. Positive axillary lymph nodes were found in 16.8% of cases.

Conclusions

The attendance to screening was satisfactory. A higher frequency of small tumors (83.0%) was found at first screening than before the introduction of screening (56.6%). A marked difference in lymph node positivity (24.0% vs 40.6% in the pre-screening era) was also observed. Such a difference was even more evident at repeat screening. Quality standards of the screening in our study proved to be higher than those currently recommended. The reported results are encouraging, also considering the greater chance for conservative treatment.

Digital liver biopsy: Bio-imaging of fatty liver for translational and clinical research

The rapidly growing field of functional, molecular and structural bio-imaging is providing an extraordinary new opportunity to overcome the limits of invasive liver biopsy and introduce a "digital biopsy" for in vivo study of liver pathophysiology. To foster the application of bio-imaging in clinical and translational research, there is a need to standardize the methods of both acquisition and the storage of the bio-images of the liver. It can be hoped that the combination of digital, liquid and histologic liver biopsies will provide an innovative synergistic tri-dimensional approach to identifying new aetiologies, diagnostic and prognostic biomarkers and therapeutic targets for the optimization of personalized therapy of liver diseases and liver cancer. A group of experts of different disciplines (Special Interest Group for Personalized Hepatology of the Italian Association for the Study of the Liver, Institute for Biostructures and Bio-imaging of the National Research Council and Bio-banking and Biomolecular Resources Research Infrastructure) discussed criteria, methods and guidelines for facilitating the requisite application of data collection. This manuscript provides a multi-Author review of the issue with special focus on fatty liver.

Fibrinogen Gamma Chain Mutations Provoke Fibrinogen and Apolipoprotein B Plasma Deficiency and Liver Storage

p.R375W (Fibrinogen Aguadilla) is one out of seven identified mutations (Brescia, Aguadilla, Angers, Al du Pont, Pisa, Beograd, and Ankara) causing hepatic storage of the mutant fibrinogen γ. The Aguadilla mutation has been reported in children from the Caribbean, Europe, Japan, Saudi Arabia, Turkey, and China. All reported children presented with a variable degree of histologically proven chronic liver disease and low plasma fibrinogen levels. In addition, one Japanese and one Turkish child had concomitant hypo-APOB-lipoproteinemia of unknown origin. We report here on an additional child from Turkey with hypofibrinogenemia due to the Aguadilla mutation, massive hepatic storage of the mutant protein, and severe hypo-APOB-lipoproteinemia. The liver biopsy of the patient was studied by light microscopy, electron microscopy (EM), and immunohistochemistry. The investigation included the DNA sequencing of the three fibrinogen and APOB-lipoprotein regulatory genes and the analysis of the encoded protein structures. Six additional Fibrinogen Storage Disease (FSD) patients with either the Aguadilla, Ankara, or Brescia mutations were investigated with the same methodology. A molecular analysis revealed the fibrinogen gamma p.R375W mutation (Aguadilla) but no changes in the APOB and MTTP genes. APOB and MTTP genes showed no abnormalities in the other study cases. Light microscopy and EM studies of liver tissue samples from the child led to the demonstration of the simultaneous accumulation of both fibrinogen and APOB in the same inclusions. Interestingly enough, APOB-containing lipid droplets were entrapped within the fibrinogen inclusions in the hepatocytic Endoplasmic Reticulum (ER). Similar histological, immunohistochemical, EM, and molecular genetics findings were found in the other six FSD cases associated with the Aguadilla, as well as with the Ankara and Brescia mutations. The simultaneous retention of fibrinogen and APOB-lipoproteins in FSD can be detected in routinely stained histological sections. The analysis of protein structures unraveled the pathomorphogenesis of this unexpected phenomenon. Fibrinogen gamma chain mutations provoke conformational changes in the region of the globular domain involved in the "end-to-end" interaction, thus impairing the D-dimer formation. Each monomeric fibrinogen gamma chain is left with an abnormal exposure of hydrophobic patches that become available for interactions with APOB and lipids, causing their intracellular retention and impairment of export as a secondary unavoidable phenomenon.

The surgical pathology laboratory in Mwanza, Tanzania: a survey on the reproducibility of diagnoses after the first years of autonomous activity

BACKGROUND

In 2000, an Italian non-governmental organisation (NGO) began a 9-year project to establish a surgical pathology laboratory at the Bugando Medical Centre (BMC) in Mwanza, Tanzania, a country with a low Human Development Index (HDI), and as of 2009, the laboratory was operating autonomously. The present survey aims to evaluate the reproducibility of histological and cytological diagnoses assigned in the laboratory's early years of autonomous activity. We selected a random sample of 196 histological and cytological diagnoses issued in 2010-2011 at the BMC surgical pathology laboratory. The corresponding samples were sent to Italy for review by Italian senior pathologists, who were blinded to the local results. Samples were classified into four diagnostic categories: malignant, benign, inflammatory, and suspicious. The two-observer kappa-statistic for categorised (qualitative) data was then calculated to measure diagnostic concordance between the local Tanzanian pathologists and Italian senior pathologists. The k-Cohen was calculated for concordance in the overall study sample. Concordance and discordance rates were also stratified by subset: general adult, paediatric/adolescent, and lymphoproliferative histopathological diagnoses; fluid and fine needle aspiration (FNA) cytological diagnoses; and PAP tests. Discordance was also categorised by the corresponding hypothetical clinical implications: high, intermediate, and not significant.

RESULTS

Overall concordance was 85.2% (167 of 196 diagnoses), with a k-Cohen of 0.7691 (P = 0.0000). Very high concordance was observed in the subsets of adult general pathological diagnoses (90%) and paediatric/adolescent pathological diagnoses (91.18%). Concordance in the subset of PAP tests was 75%, and for fluid/FNA cytological diagnoses it was 56.52%. Concordance among 12 histological subtypes of lymphoma was 75.86%, with substantial discordance observed in the diagnosis of Burkitt lymphoma (five cases diagnosed by Italian pathologists versus 2 by local pathologists). The overall proportion of discordance with high hypothetical clinical implications was 6.1% (12 diagnoses).

CONCLUSION

This blind review of diagnoses assigned in Tanzania, a country with low HDI, and in Italy, a country with a very high HDI, seemed to be a sensitive and effective method to identify areas of potential error and may represent a reference point for future, more detailed quality control processes or audits of surgical pathology services located in limited-resource regions.

A waterborn zoonotic helminthiase in an Italian diver: a case report of a cutaneous Sparganum infection and a review of European cases

Many waterborne helminthes are opportunistic parasites that can travel directly from animals to man and may contain forms capable of penetrating the skin. Among these, Sparganum is the pseudophyllidean tapeworm that belongs to the genus Spirometra, which is responsible for parasitic zoonosis; it is rarely detected in Europe and is caused by the plerocercoid infective larva. Thus far, only six cases of cutaneous and ocular sparganosis have been reported in Europe; two and four cases have occurred in France and Italy, respectively. Herein, we describe a new case of sparganosis in Italy that affected a male diver who presented to the Bambino Gesù Children's Hospital of Rome. The patient's skin biopsy was submitted to the Parasitology department who, in consultation with Pathology, concluded that the morphologic and microscopic findings were those of Sparganum spp. larvae. The patient recovered following a single dose of 600 mg praziquantel.

Genetics and Molecular Modeling of New Mutations of Familial Intrahepatic Cholestasis in a Single Italian Center

Familial intrahepatic cholestases (FICs) are a heterogeneous group of autosomal recessive disorders of childhood that disrupt bile formation and present with cholestasis of hepatocellular origin. Three distinct forms are described: FIC1 and FIC2, associated with low/normal GGT level in serum, which are caused by impaired bile salt secretion due to defects in ATP8B1 encoding the FIC1 protein and defects in ABCB11 encoding bile salt export pump protein, respectively; FIC3, linked to high GGT level, involves impaired biliary phospholipid secretion due to defects in ABCB4, encoding multidrug resistance 3 protein. Different mutations in these genes may cause either a progressive familial intrahepatic cholestasis (PFIC) or a benign recurrent intrahepatic cholestasis (BRIC). For the purposes of the present study we genotyped 27 children with intrahepatic cholestasis, diagnosed on either a clinical or histological basis. Two BRIC, 23 PFIC and 2 BRIC/PFIC were identified. Thirty-four different mutations were found of which 11 were novel. One was a 2Mb deletion (5’UTR- exon 18) in ATP8B1. In another case microsatellite analysis of chromosome 2, including ABCB11, showed uniparental disomy. Two cases were compound heterozygous for BRIC/PFIC2 mutations. Our results highlight the importance of the pathogenic role of novel mutations in the three genes and unusual modes of their transmission.

Fibrinogen storage disease and cirrhosis associated with hypobetalipoproteinemia owing to fibrinogen Aguadilla in a Turkish child

BACKGROUND AND AIMS

Fibrinogen gene mutations can rarely result in hepatic fibrinogen storage disease (HFSD). Herein, we report on the first Turkish family carrying the mutation p.Arg375Trp (fibrinogen Aguadilla) in the γ-chain of the fibrinogen (FGG) gene.

METHODS

Clinical, laboratory and histopathological findings of the patient were documented. Molecular study of fibrinogen gene was performed in the patient and her family members.

RESULTS

The proband was 5 years old girl presenting with advanced liver fibrosis of unknown origin. The child had very low plasma levels of fibrinogen and hypobetalipoproteinemia. Immunomorphologic and electron microscopic studies showed selective and exclusive accumulation of fibrinogen within the endoplasmic reticulum in liver biopsy of the patient. Patient, mother, two sisters and one brother carried p.Arg375Trp mutation (fibrinogen Aguadilla) in FGG gene. The patient was treated with ursodeoxycholic acid and carbamazepine. After 3 months, carbamazepine was suspended upon family decision and unresponsiveness of carbamazepine.

CONCLUSIONS

HFSD is characterized by hypofibrinogenemia and accumulation of abnormal fibrinogen within hepatocytes. In addition, hypofibrinogenemia is associated with hypobetalipoproteinemia in Aguadilla mutation.

Frequent detection of antiretroviral drug resistance in HIV-1-infected orphaned children followed at a donor-funded rural pediatric clinic in Dodoma, Tanzania

A total of 81 HIV-1 protease (PR) and reverse transcriptase (RT) sequences were obtained from 46 drug-naive and 35 pretreated individual HIV-1-infected orphaned children followed at a donor-funded rural pediatric clinic in Dodoma, Tanzania. PR and RT sequencing was performed by home-brew technology on 70 plasma samples and 11 dried blood spot specimens. Nucleoside RT inhibitor (NRTI) resistance mutations were detected in 2.2% of drug-naive and 82.9% of pretreated children. Nonnucleoside RT inhibitor (NNRTI) resistance mutations were detected in 69.6% of drug-naive and 91.4% of pretreated children. Resistance to protease inhibitors was rare (8.6% in pretreated children). Based on few complete treatment records, only around 20% of the treated children had undetectable plasma HIV-1 RNA. The rate of NRTI and NNRTI resistance in this donor-funded rural pediatric clinic was high and appeared to limit virological response to treatment.

Multi-drugs resistant acne rosacea in a child affected by Ataxia-Telangiectasia: successful treatment with Isotretinoin

Ataxia-Telangiectasia is a rare multisystem autosomal recessive disorder [OMIM 208900], caused by mutations in Ataxia-Telangiectasia Mutated gene. It is characterized by neurological, immunological and cutaneous involvement. Granulomas have been previously reported in Ataxia-Telangiectasia patients, even if acne rosacea has not been described.

We report a case of a young Ataxia-Telangiectasia patient with a severe immunological and neurological involvement, who developed granulomatous skin lesions diagnosed by skin biopsy as acne rosacea. Considering the severe clinical picture and the lack of improvement to multiple topic and systemic therapies, treatment with Isotretinoin was started and the skin lesions disappeared after five months. However the therapy was stopped due to drug-hepatotoxicity.

Systemic treatment with Isotretinoin should be carefully considered in patient with Ataxia-Telangiectasia for the treatment of multi-drug resistant acne rosacea, however its toxicity may limit long-term use and the risk/benefit ratio of the treatment should be evaluated.

Alpha-1-antitrypsin deficiency: from genoma to liver disease. PiZ mouse as model for the development of liver pathology in human

BACKGROUND & AIMS

Homozygous individuals with alpha-1-antitrypsin deficiency (AATD) type PiZ have an increased risk of chronic liver disease and hepatocellular carcinoma (HCC). It is noteworthy that HCCs are composed by hepatocytes without accumulation of AAT, but the reason for this remains unclear. The aim of this study was to determine liver pathology in PiZ mice, focusing the attention on the distribution of AAT globules in normal liver, regenerative foci and neoplastic nodules.

METHODS

Liver of 79 PiZ mice and 18 wild type (Wt) was histologically analysed for steatosis, clear cell foci, hyperplasia and neoplasia. The expression of human-AAT transgene and murine AAT, in non-neoplastic liver and in hyperplastic/neoplastic nodules was tested by qPCR and qRT-PCR. RT-PCR was used to study expression of hepatic markers: albumin, α-foetoprotein, transthyretin, AAT, glucose-6-phospate, tyrosine aminotransferase.

RESULTS

Liver pathology was seen more frequently in PiZ (47/79) than in Wt (5/18) and its development was age related. In older PiZ mice (18-24 m), livers showed malignant tumours (HCC and angiosarcoma) (17/50), hyperplastic nodules (28/50), non-specific changes (33/50), whereas only 9/50 were normal. Both human-AATZ DNA and mRNA showed no differences between tumours/nodules and normal liver, while murine-AAT mRNA was reduced in tumours/nodules.

CONCLUSION

Accumulation of AAT is associated with an increased risk of liver nodules. The presence of globule-devoid hepatocytes and the reduced expression of murine-AAT mRNA in hyperplastic and neoplastic nodules suggest that these hepatic lesions in AATD could originate from proliferating dedifferentiated cells, lacking AAT storage and becoming capable of AFP re-expression.

Heart transplant and 2-year follow up in a child with generalized arterial calcification of infancy

Generalized arterial calcification of infancy (GACI, OMIM 208000) and pseudoxanthoma elasticum (PXE, OMIM 264800) are rare autosomal-recessive disorders which represent the opposite ends of the same spectrum of pathologies characterized by progressive ectopic calcification and degeneration of elastic fibers at skin, eyes, and cardiovascular level. Patients with GACI suffer from hypertension, severe myocardial ischemia, and congestive heart failure and often die within 6 months of life. On the other end, PXE is associated with considerable morbidity, rarely with mortality. GACI and PXE are associated with biallelic mutations in ENPP1 and in ABCC6. We report the case of a 4-year-old Italian child submitted to heart transplant, at 18 months old, for end-stage heart failure due to extensive myocardial infarction of the left ventricle and diffuse coronary calcifications. The histology showed generalized arterial calcification and the molecular analysis identified mutations in ABCC6. Two years after transplantation, the child shows good clinical conditions and growth with no recurrence of calcium deposits in the heart.

CONCLUSION

Bisphosphonate therapy at present is the treatment of choice for systemic arterial involvement in GACI, and heart transplant has proven to be the definitive treatment in case with extensive myocardial infarction, as in our. Molecular analysis is mandatory for a complete diagnosis and familial counseling.

A rare case of segmental neurofibromatosis with multiple blue-red pseudoatrophic plaques

We report the case of a 5-year-old girl who presented with 2 blue-red atrophic plaques on the left leg as well as subcutaneous nodules that were present since infancy. Although the clinical criteria of neurofibromatosis (NF) were absent, microscopic examination revealed features of a blue-red neurofibroma.

Buschke-Ollendorff syndrome: sparing unnecessary investigations

Buschke-Ollendorff syndrome (BOS) is an autosomal-dominant disease characterized by the association of connective tissue nevi and osteopoikilosis. It is diagnosed by mutations of proteins involved in bone and connective tissue morphogenesis. We report 2 cases of BOS with different cutaneous clinical patterns. These cases emphasize the importance of heightened suspicion of BOS in selected cases. Identifying BOS can be reassuring for the patient, sparing futile and expensive investigations.

Pathology of the liver sinusoids

The hepatic sinusoids comprise a complex of vascular conduits to transport blood from the porta hepatis to the inferior vena cava through the liver. Under normal conditions, portal venous and hepatic artery pressures are equalized within the sinusoids, oxygen and nutrients from the systemic circulation are delivered to the parenchymal cells and differentially distributed throughout the liver acini, and proteins of liver derivation are carried into the cardiac/systemic circulation. Liver sinusoid structures are lined by endothelial cells unique to their location, and Kupffer cells. Multifunctional hepatic stellate cells and various immune active cells are localized within the space of Disse between the sinusoid and the adjacent hepatocytes. Flow within the sinusoids can be compromised by physical or pressure blockage in their lumina as well as obstructive processes within the space of Disse. The intimate relationship of the liver sinusoids to neighbouring hepatocytes is a significant factor affecting the health of hepatocytes, or transmission of the effects of injury within the sinusoidal space. Pathologists should recognize several patterns of injury involving the sinusoids and surrounding hepatocytes. In this review, injury, alterations and accumulations within the liver sinusoids are illustrated and discussed.

Malignant pheochromocytoma in a 16-year-old patient with neurofibromatosis type 1

Patients with neurofibromatosis type I (NF1) feature a high risk of developing benign and malignant tumors, mainly those with a neuroectodermal origin, the risk being about 4 times higher than in the general population. Pheochromocytoma (PHEO) is a sporadic tumor (1∶100,000) arising from the adrenal medulla. Pheochromocytoma is a rare condition when occurring in conjunction with NF1 and occurs in about 1% of patients, rarely in those of pediatric age. In this study we present a 16-year-old patient with NF1 and malignant PHEO. Loss of heterozygosity analysis in PHEOs shows a reduction to homozygosity, observed for both 17p and 17q markers. This case confirms the importance of surveillance for malignant neoplasias in NF1 patients during childhood and adolescence. On the other hand, since 30% of PHEOs had germline mutations and, more rarely, somatic mutations, patients with PHEO should be investigated for associated genetic syndromes.

Hepatic fibrinogen storage disease due to the fibrinogen γ375 Arg → Trp mutation "fibrinogen Aguadilla" is present in Arabs

The mutation γ375Arg → Trp (fibrinogen Aguadilla) is one of four mutations (Brescia, Aguadilla, Angers, and AI duPont) capable of causing hepatic storage of fibrinogen. It has been observed in four children from the Caribbean, Europe, and Japan, suffering from cryptogenic liver disease. We report the first case of hepatic fibrinogen storage disease in Arabs due to a mutation in the fibrinogen γ-chain gene in a 3-year-old Syrian girl presenting with elevated liver enzymes. The finding of an impressive accumulation of fibrinogen in liver cells raised the suspicion of endoplasmic reticulum storage disease. Sequencing of the fibrinogen genes revealed a γ375Arg → Trp mutation (fibrinogen Aguadilla) in the child and in her father. In conclusion, when confronted with chronic hepatitis of unknown origin, one should check the plasma fibrinogen level and look carefully for the presence of hepatocellular intracytoplasmic globular inclusions to exclude hepatic fibrinogen storage disease.

Congenital myxoid and pigmented dermatofibrosarcoma protuberans: a case report

Dermatofibrosarcoma protuberans (DFSP) is a low-grade, mesenchymal, spindle cell tumor. In addition to the classical form characterized by a storiform pattern of tumor cells, pigmented (Bednar's tumor) and myxoid variants can be observed. Classical DFSP and Bednar's tumor are easily diagnosed. The myxoid variant represents a diagnostic challenge. Pigmented and myxoid variants are rare and thus far have never been reported in association in congenital DFSP. We came across a unique DFSP that was, at the same time, congenital, pigmented, and myxoid. The tumor was surgically excised with broad free margins and no recurrence. The differential diagnosis with other entities such as giant cell fibroblastoma, CD34-positive plaque-like dermal fibroma, superficial plaque-like CD34 DFSP, and neurocristic hamartoma is discussed. The recognition of this hybrid variant of congenital DFSP is important to avoid under- or overtreatment.

Impressive pseudotumoral proliferative nodules in a giant congenital nevus of a newborn

The potential for malignant transformation of a giant congenital melanocytic nevus (GCMN), although rare, should be considered, especially in proliferative lesions that have nodules on their surface, as they can clinically and histologically mimic melanoma and generally have a poor prognosis. We present the case of a newborn boy with a giant nevus of uneven blackish color on the back with variable degrees of intensity of pigmentation, almost entirely covered by nodules of large and variable sizes, soft texture, and a tendency to ulcerate and bleed. The unusual clinical and histologic appearance made the case particularly interesting and featured a not well-defined biologic behavior, thus deserving a radical surgical approach to fulfill diagnostic and therapeutic aims.

Ductopenia and fetal liver-like architecture as unique and evocative sign of Turner syndrome

BACKGROUND

Turner syndrome is the most common genetic disorder in females. In most subjects, with a normal physical appearance at birth, the diagnosis is suspected long after birth because of short stature, delayed puberty, primary or secondary amenorrhea or infertility. Abnormalities of liver function tests are reported in literature, with a prevalence ranging from 20% to 80%. In most subjects liver diseases are self-limiting, associated with obesity, hormonal therapy and autoimmune diseases. An association between Turner syndrome and cryptogenic liver disease has been reported. Abnormalities of liver function tests could be the unique sign of Turner syndrome in subjects with normal phenotypes. The histological picture of "fetal liver-like architecture" and "ductopenia" is of fundamental importance for the diagnosis of chromosomopathy.

AIM

Review the causes of hypertransaminasemia by focusing on more rare as metabolic and genetic diseases.

MATERIALS AND METHODS

We evaluated a 10 year old girl with a normal phenotype affected by chronic hypertransaminasemia and cholestasis, in whom a needle liver biopsy was performed after the most common causes of hypertransaminasemia were excluded.

RESULTS

Liver histological evaluation revealed a smoldering colangiopathy with mild ductopenia and a fetal liver-like architecture. Turner syndrome, suspected on the basis of this histological picture, was confirmed by a pelvic ultrasound and a chromosome analysis.

CONCLUSIONS

The histological features of "fetal liver-like architecture" and "ductopenia" represent an evocative sign that could indicate the diagnostic suspicion of Turner syndrome in a subject lacking in signs or symptoms of this disease. It is important to perform a pelvic ultrasound and an endocrinological evaluation in all females with chronic asymptomatic hypertransaminasemia even though they have normal phenotypes.

Bile salt export pump deficiency: A de novo mutation in a child compound heterozygous for ABCB11. Laboratory investigation to study pathogenic role and transmission of two novel ABCB11 mutations

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous group of autosomal disorders. PFIC type 2 is due to mutation in ABCB11, the gene encoding the bile salt export pump (BSEP) protein. The aim of the study was to describe a child with a de novo mutation in a compound heterozygous for ABCB11 gene. We report a 1.7-year-old girl who presented with pruritus, jaundice and liver dysfunction of PFIC type 2. Immunohistochemistry and molecular analysis are described. Liver biopsy showed micronodular cirrhosis and immunohistochemical staining for BSEP, the protein encoded by ABCB11, displayed a patchy and faint reactivity. Molecular analysis revealed two novel mutations of ABCB11. We give details that one mutation is transmitted by the mother while the second one appears a de novo mutation as mutations or a potential mosaicism were ruled out in the natural father. We further speculate that the ABCB11 mutations do not prevent BSEP glycoprotein to be expressed at the canalicular pole of hepatocytes, but interfere with its ability to export bile salts. As in most instances, mutational analysis is performed following the histochemical demonstration of an undetectable BSEP on liver biopsy specimen. This case stresses that clinical PFIC with an attenuated rather than absent BSEP immunostaining can still be due to ABCB11 mutations presumably encoding a functionally deficient protein.

Bile salt export pump deficiency: A de novo mutation in a child compound heterozygous for ABCB11. Laboratory investigation to study pathogenic role and transmission of two novel ABCB11 mutations

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous group of autosomal disorders. PFIC type 2 is due to mutation in ABCB11, the gene encoding the bile salt export pump (BSEP) protein. The aim of the study was to describe a child with a de novo mutation in a compound heterozygous for ABCB11 gene. We report a 1.7-year-old girl who presented with pruritus, jaundice and liver dysfunction of PFIC type 2. Immunohistochemistry and molecular analysis are described. Liver biopsy showed micronodular cirrhosis and immunohistochemical staining for BSEP, the protein encoded by ABCB11, displayed a patchy and faint reactivity. Molecular analysis revealed two novel mutations of ABCB11. We give details that one mutation is transmitted by the mother while the second one appears a de novo mutation as mutations or a potential mosaicism were ruled out in the natural father. We further speculate that the ABCB11 mutations do not prevent BSEP glycoprotein to be expressed at the canalicular pole of hepatocytes, but interfere with its ability to export bile salts. As in most instances, mutational analysis is performed following the histochemical demonstration of an undetectable BSEP on liver biopsy specimen. This case stresses that clinical PFIC with an attenuated rather than absent BSEP immunostaining can still be due to ABCB11 mutations presumably encoding a functionally deficient protein.

Novel large-range mitochondrial DNA deletions and fatal multisystemic disorder with prominent hepatopathy

Hepatic involvement in mitochondrial cytopathies rarely manifests in adulthood, but is a common feature in children. Multiple OXPHOS enzyme defects in children with liver involvement are often associated with dramatically reduced amounts of mtDNA. We investigated two novel large scale deletions in two infants with a multisystem disorder and prominent hepatopathy. Amount of mtDNA deletions and protein content were measured in different post-mortem tissues. The highest levels of deleted mtDNA were in liver, kidney, pancreas of both patients. Moreover, mtDNA deletions were detected in cultured skin fibroblasts in both patients and in blood of one during life. Biochemical analysis showed impairment of mainly complex I enzyme activity. Patients manifesting multisystem disorders in childhood may harbour rare mtDNA deletions in multiple tissues. For these patients, less invasive blood specimens or cultured fibroblasts can be used for molecular diagnosis. Our data further expand the array of deletions in the mitochondrial genomes in association with liver failure. Thus analysis of mtDNA should be considered in the diagnosis of childhood-onset hepatopathies.

Two novel mutations in African and Asian children with progressive familial intrahepatic cholestasis type 3

BACKGROUND

Defects in ABCB4 have been found to cause progressive familial intrahepatic cholestasis type 3. Liver histology is important, but not specific, for diagnosis. Genotyping is conclusive.

AIM

To determine the pathogenetic role of two novel ABCB4 mutations in two unrelated children from North Africa and South Asia.

METHODS

In both children liver histology showed extensive ductular reaction with portal and periportal fibrosis. Immunohistochemical analysis displayed absence of MDR3 protein expression at the canalicular pole. Genotype analysis was performed.

RESULTS

Genotyping revealed two novel mutations in ABCB4: the c.1783 C>T (p.R595X) mutation in exon 15 was detected in compound heterozygosity with the c.937_992 in/del in exon 9 in one case, whereas the homozygous p.R595X mutation was recognized in the second child.

CONCLUSIONS

Two novel loss-of-function mutations have been identified. Progressive familial intrahepatic cholestasis type 3 has a worldwide distribution and genetic analyses are conclusive for correct diagnosis.

Unresectable multifocal omental and peritoneal inflammatory myofibroblastic tumor in a child: revisiting the role of adjuvant therapy

Inflammatory myofibroblastic tumor is an uncommon lesion, also called pseudotumor, with a variable natural course from benign with spontaneous regression to mimicking malignant tumors. We report a case of diffuse peritoneal and omental pseudotumor in a 10-year-old boy characterized by aggressive behavior at the onset followed by stability after subtotal resection and chemotherapy. Total excision was not possible because of the tumor dissemination over the whole peritoneal surface. Adjuvant antiinflammatory drug (ketorolac tromethamine) and chemotherapy (methotrexate-vinblastine followed by ifosfamide-adriamycin and ifosfamide alone) were helpful to obtain rapidly complete resolution of clinical symptoms and anatomic stability of the residual lesions. Long-term evolution, in the absence of continued therapy, has been characterized by progressive involution and reduction of the residual masses.

Tyrosinemia type 1: metastatic hepatoblastoma with a favorable outcome

The clinical course of tyrosinemia type 1 is characterized by acute liver failure in infancy or chronic liver dysfunction and renal Fanconi syndrome in late-presenting cases. Dietary treatment may improve liver function but does not prevent the development of hepatocellular carcinoma (HCC) in late childhood. A new treatment strategy that uses 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC), which prevents the production of toxic/carcinogenic metabolites, has dramatically changed the outcome of the disease by reducing the occurrence of liver cancer, especially in patients who start this treatment before the age of 2 years. We report here the case of a patient with a diagnosis of tyrosinemia type 1 at 5 months of age who was treated with NTBC and dietary restriction and in whom a liver neoplasm with lung metastases, histologically determined to be HCC, was found at the age of 15 months. A conservative approach that consisted of chemotherapy and partial hepatectomy resulted in a 12-year disease-free period. The excellent postchemotherapy course, in sharp contrast to the expected course of HCC, led to histologic reevaluation with reclassification of the neoplasm as hepatoblastoma. A diagnosis of hepatoblastoma would no longer be a mandate for a liver transplant for patients with tyrosinemia type 1 undergoing NTBC treatment. We encourage clinicians to perform more accurate evaluation of liver histology, because a neoplastic mass in a child with tyrosinemia type 1 is not the same as HCC.