Lymphedema complicated by protein-losing enteropathy with a 22q13.3 deletion and the potential role of CELSR1: A case report

INTRODUCTION

22q13.3 deletion syndrome is a well-known syndrome characterized by typical clinical findings including neonatal hypotonia, absent or severely delayed speech, intellectual disability, and other various features, and detection of a heterozygous deletion of chromosome 22q13.3 with the involvement of at least part of SHANK3. It is reported that 10% to 29% of patients with 22q13.3 deletion syndrome present lymphedema. Protein-losing enteropathy (PLE) has never been reported in 22q13.3 deletion syndrome.

PATIENT CONCERNS

The patient presented to our institution for refractory hypoalbuminemia and chronic lymphedema in both legs.

DIAGNOSIS

The patient manifested intellectual disability, absent speech, tooth grinding, dysmorphic face, and abnormal hands and toenails. Copy-number variation sequencing confirmed the maternal deletion in 22q13.31-q13.33 (chr22:46285592-51244566, hg19). The patient was genetically diagnosed with 22q13.3 deletion syndrome.

INTERVENTIONS

Low-fat diets and medium-chain triglycerides supplements were prescribed. The patient was recommended to wear compression garments and elevate legs.

OUTCOMES

The symptom of diarrhea was resolved, but hypoalbuminemia persisted. Lower extremities lymphedema was gradually becoming severe.

CONCLUSIONS

Primary lymphedema and PLE can occur simultaneously in a patient with 22q13.3 deletion syndrome. The 2 phenotypes could share the same genetic etiology of congenital lymphatic abnormalities. CELSR1 deletion may play a role in lymphatic dysplasia. The case also provides additional proof of the pathogenic effect of CELSR1 on hereditary lymphedema.

An initial genome-wide investigation of protein-losing enteropathy in Gordon setters: Exploratory observations

The objective of this preliminary study was to identify genomic regions that may predispose Gordon setters from the United Kingdom to familial protein-losing enteropathy (PLE) at a young age. A total of 106 related Gordon setters was used, including 6 affected dogs from an affected litter, 6 case controls from the same litter, 10 related/affected dogs, and 84 related/unaffected dogs. Genomic DNA was collected from each Gordon setter and extracted from buccal mucosal swabs. Genotyping of affected and unaffected dogs was carried out using the Canine Illumina HD SNP array and data generated were analyzed with PLINK software, using fixation index (Fst) and runs of homozygosity (ROH) methods. Pairwise Fst analyses between the affected and unaffected Gordon setter dogs identified various regions of differentiation on chromosomes 10, 18, 21, and 23 that contained several important genes. These regions revealed 5 candidate genes, including RARB, TTC7A, SOCS5, PIGF, and RHOD, that are associated with human inflammatory bowel disease (IBD) and could potentially be associated with PLE in Gordon setters. Run of homozygosity (ROH) analyses revealed additional unique regions on chromosomes 15 and 17. These regions contained genes SYT1, UCN, and FNDC that could also be potential candidates for PLE in Gordon setters. The biological functions of the identified genes provided initial insights into the pathophysiology of PLE. Further large-scale studies are warranted to investigate the possible causality of these genomic regions and any possible genetic markers that could be used in predicting susceptibility to PLE syndrome.

Enhanced Collagen Deposition in the Duodenum of Patients with Hyaline Fibromatosis Syndrome and Protein Losing Enteropathy

Hyaline fibromatosis syndrome (HFS), resulting from ANTXR2 mutations, is an ultra-rare disease that causes intestinal lymphangiectasia and protein-losing enteropathy (PLE). The mechanisms leading to the gastrointestinal phenotype in these patients are not well defined. We present two patients with congenital diarrhea, severe PLE and unique clinical features resulting from deleterious ANTXR2 mutations. Intestinal organoids were generated from one of the patients, along with CRISPR-Cas9 ANTXR2 knockout, and compared with organoids from two healthy controls. The ANTXR2-deficient organoids displayed normal growth and polarity, compared to controls. Using an anthrax-toxin assay we showed that the c.155C>T mutation causes loss-of-function of ANTXR2 protein. An intrinsic defect of monolayer formation in patient-derived or ANTXR2KO organoids was not apparent, suggesting normal epithelial function. However, electron microscopy and second harmonic generation imaging showed abnormal collagen deposition in duodenal samples of these patients. Specifically, collagen VI, which is known to bind ANTXR2, was highly expressed in the duodenum of these patients. In conclusion, despite resistance to anthrax-toxin, epithelial cell function, and specifically monolayer formation, is intact in patients with HFS. Nevertheless, loss of ANTXR2-mediated signaling leads to collagen VI accumulation in the duodenum and abnormal extracellular matrix composition, which likely plays a role in development of PLE.

Glycomacropeptide Ameliorates Indomethacin-Induced Enteropathy in Rats by Modifying Intestinal Inflammation and Oxidative Stress

Nonsteroidal anti-inflammatory drug (NSAID)-induced enteropathy is considered a serious and increasing clinical problem without available treatment. Glycomacropeptide (GMP) is a 64-amino acid peptide derived from milk κ-casein with numerous biological activities. The aim of this study was to investigate the protective effect of GMP on NSAID enteropathy in rats. Enteropathy was induced by seven days oral indomethacin administration. Rats were orally GMP treated from seven days previous and during the establishment of the enteropathy model. Changes in metabolism, hematological and biochemical blood alterations, intestinal inflammation and oxidative damage were analyzed. Integrity barrier markers, macroscopic intestinal damage and survival rate were also evaluated. GMP treatment prevented anorexia and weight loss in animals. Furthermore, prophylaxis with GMP ameliorated the decline in hemoglobin, hematocrit, albumin and total protein levels. The treatment had no therapeutic efficacy on the decrease of occludin and mucin (MUC)-2 expression in intestinal tissue. However, GMP markedly decreased neutrophil infiltration, and CXCL1, interleukin-1β and inducible nitric oxide synthase expression. Nitric oxide production and lipid hydroperoxide level in the small intestine were also diminished. These beneficial effects were mirrored by preventing ulcer development and increasing animal survival. These results suggest that GMP may protect against NSAID enteropathy through anti-inflammatory and antioxidant properties.

Phenotype and Genotype of a Cohort of Chinese Children with Early-Onset Protein-Losing Enteropathy

OBJECTIVES

To examine the phenotypes and perform next-generation sequencing in children with early-onset protein-losing enteropathy.

STUDY DESIGN

We performed a retrospective review of 27 children with early-onset protein-losing enteropathy. Patients were characterized on clinical, immunologic, and systemic involvements. Targeted gene panel sequencing and whole-exome sequencing were performed in 9 patients.

RESULTS

In 27 patients (55.6% male), median age of disease onset was 173 days, and 59.3% had onset of disease before 1 year of age. Initial gastrointestinal symptoms included diarrhea (74.1%), vomiting (33.3%), and abdominal distention (48.1%). All patients had hypoalbuminemia, with an average serum albumin concentration of 20.2 ± 5.4 g/L. Hypogammaglobulinemia was identified in 72% of the patients. Upper endoscopy showed typical presentation of intestinal lymphangiectasia (n = 13). Patients frequently received intravenous albumin and immunoglobulin infusions as well as parenteral nutrition. Next-generation sequencing in 9 patients with available DNA showed 1 patient had compound heterozygous CCBE1 mutations and 2 had novel homozygous DGAT1 mutations. Monogenic diseases were identified in 3 of 9 patients who underwent genetic sequencing. Three subjects (11.1%) died, of whom 2 had homozygous DGAT1 mutations. No significant correlation was found between age of symptom onset, serum albumin, serum IgG, lymphocyte count, CD4⁺ cells, and mortality.

CONCLUSIONS

Monogenic diseases may be observed in children with early-onset protein-losing enteropathy, and genetic evaluation with next-generation sequencing should be considered.

Mutations in plasmalemma vesicle-associated protein cause severe syndromic protein-losing enteropathy

BACKGROUND

Protein-losing enteropathy (PLE) is characterised by gastrointestinal protein leakage due to loss of mucosal integrity or lymphatic abnormalities. PLE can manifest as congenital diarrhoea and should be differentiated from other congenital diarrhoeal disorders. Primary PLEs are genetically heterogeneous and the underlying genetic defects are currently emerging.

OBJECTIVES

We report an infant with fatal PLE for whom we aimed to uncover the underlying pathogenic mutation.

METHODS

We performed whole exome sequencing (WES) for the index patient. Variants were classified based on the American College of Medical Genetics and Genomics guidelines. WES results and our detailed clinical description of the patient were compared with the literature.

RESULTS

We discovered a novel homozygous stop mutation (c.988C>T, p.Q330*) in the Plasmalemma Vesicle-Associated Protein (PLVAP) gene in a newborn with fatal PLE, facial dysmorphism, and renal, ocular and cardiac anomalies. The Q330* mutation is predicted to result in complete loss of PLVAP protein expression leading to deletion of the diaphragms of endothelial fenestrae, resulting in plasma protein extravasation and PLE. Recently, another single homozygous stop mutation in PLVAP causing lethal PLE in an infant was reported.

CONCLUSIONS

Our findings validate PLVAP mutations as a cause of syndromic PLE. Prenatal anomalies, severe PLE and syndromic features may guide the diagnosis of this rare disease.

CD55 Deficiency, Early-Onset Protein-Losing Enteropathy, and Thrombosis

BACKGROUND

Studies of monogenic gastrointestinal diseases have revealed molecular pathways critical to gut homeostasis and enabled the development of targeted therapies.

METHODS

We studied 11 patients with abdominal pain and diarrhea caused by early-onset protein-losing enteropathy with primary intestinal lymphangiectasia, edema due to hypoproteinemia, malabsorption, and less frequently, bowel inflammation, recurrent infections, and angiopathic thromboembolic disease; the disorder followed an autosomal recessive pattern of inheritance. Whole-exome sequencing was performed to identify gene variants. We evaluated the function of CD55 in patients' cells, which we confirmed by means of exogenous induction of expression of CD55.

RESULTS

We identified homozygous loss-of-function mutations in the gene encoding CD55 (decay-accelerating factor), which lead to loss of protein expression. Patients' T lymphocytes showed increased complement activation causing surface deposition of complement and the generation of soluble C5a. Costimulatory function and cytokine modulation by CD55 were defective. Genetic reconstitution of CD55 or treatment with a complement-inhibitory therapeutic antibody reversed abnormal complement activation.

CONCLUSIONS

CD55 deficiency with hyperactivation of complement, angiopathic thrombosis, and protein-losing enteropathy (the CHAPLE syndrome) is caused by abnormal complement activation due to biallelic loss-of-function mutations in CD55. (Funded by the National Institute of Allergy and Infectious Diseases and others.).

Congenital protein losing enteropathy: an inborn error of lipid metabolism due to DGAT1 mutations

Protein-losing enteropathy (PLE) is a clinical disorder of protein loss from the gastrointestinal system that results in hypoproteinemia and malnutrition. This condition is associated with a wide range of gastrointestinal disorders. Recently, a unique syndrome of congenital PLE associated with biallelic mutations in the DGAT1 gene has been reported in a single family. We hypothesize that mutations in this gene are responsible for undiagnosed cases of PLE in infancy. Here we investigated three children in two families presenting with severe diarrhea, hypoalbuminemia and PLE, using clinical studies, homozygosity mapping, and exome sequencing. In one family, homozygosity mapping using SNP arrays revealed the DGAT1 gene as the best candidate gene for the proband. Sequencing of all the exons including flanking regions and promoter regions of the gene identified a novel homozygous missense variant, p.(Leu295Pro), in the highly conserved membrane-bound O-acyl transferase (MBOAT) domain of the DGAT1 protein. Expression studies verified reduced amounts of DGAT1 in patient fibroblasts. In a second family, exome sequencing identified a previously reported splice site mutation in intron 8. These cases of DGAT1 deficiency extend the molecular and phenotypic spectrum of PLE, suggesting a re-evaluation of the use of DGAT1 inhibitors for metabolic disorders including obesity and diabetes.

Heterogeneity and atypical presentation in infantile systemic hyalinosis with severe labio-gingival enlargement: first Egyptian report

Infantile systemic hyalinosis (ISH) (MIM 236490) is a rare, progressive, fatal autosomal recessive condition characterized by widespread deposition of hyaline material in many tissues. Our proband was a 4-year-old male with growth retardation, severe labio-gingival enlargement, generalized stiff skin, joint contractures, and intractable diarrhea. We discovered a history of a brother and sister who suffered a more severe disease course. A final diagnosis of systemic hyalinosis was made; we report this case and discuss the clinical and orodental heterogeneity among these siblings in the first report of an Egyptian family with ISH. We present a very rare entity, infantile systemic hyalinosis, a cause of joint contracture, protein-losing enteropathy, and growth retardation in infancy with a review of the relevant literature.

[Heterogeneity of type 1 diabetes mellitus]

Type 1 diabetes (T1D) comprises all forms of autoimmune-mediated and idiopathic beta-cell destruction leading to absolute insulin deficiency. The etiological heterogeneity of T1D has been recognized for the last decades, but it has been divided into only two subtypes so far: autoimmune (T1D)A and non-autoimmune (T1D)B mediated. Polygenic T1DA (isolated or associated to other autoimmune diseases) is the most prevalent type of T1D. T1DA might be part of rare monogenic syndromes related to mutations in the autoimmune regulator gene (AIRE) and FOXp3. Non-autoimmune forms of T1D correspond to approximately 4 to 7% of newly diagnosed T1D and include T1DB, as well as other types of atypical diabetes, for example fulminant type 1 diabetes and adult ketosis-prone diabetes. A new expression of diabetes in young with insulin resistance and obesity, along with the presence of pancreatic autoimmunity markers, namely auto-antibodies to islet cell antigens, is called double diabetes (DD), T1DA plus type 2 diabetes. Evidence has been collected concerning the potential effect of obesity-linked cytokines in amplifying the autoimmune response in DD. Therefore all these issues are presented and discussed in this review as the concept of heterogeneity of Type 1 Diabetes.

A potential screening tool for IPEX syndrome

IPEX syndrome is a rare, inherited condition characterized by immune dysfunction, polyendocrinopathy, enteropathy, and X-linked recessive inheritance. Patients typically present in infancy with severe diarrhea and failure to thrive. Most children die by 1 year of age without therapy. The diagnosis is established by genetic analysis, which often takes several weeks to complete and can sometimes delay crucial immunosuppressive treatment. We attempted to develop a screening tool that allows rapid identification of patients with IPEX syndrome using immunocytochemical staining of FOXP3+ cells in bowel biopsies. We found that 2 patients with classic IPEX syndrome due to protein-truncating mutations in FOXP3 had markedly decreased staining of FOXP3+ T cells in the lamina propria and lymphoid aggregates. One patient with a mild, late-onset presentation and a missense mutation in FOXP3 had intact staining of FOXP3+ cells. This screening test provides a valuable tool for diagnosing IPEX syndrome in extremely ill patients who may not tolerate a delay in therapeutic intervention.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked inheritance: model for autoaggression

Patients with the rare X-linked syndrome, immune dysregulation, polyendocrinopathy, enteropathy (IPEX) may present early in life with type I diabetes, hyperthyroidism, chronic enteropathy, villous atrophy, dermatitis, autoimmune hemolytic anemia, and antibody- induced neutropenia and thrombocytopenia. Of the reported families with IPEX, most affected boys died before the age of 3 years of malabsorbtion, failure to thrive, infections, or other complications. Characteristic findings at autopsy include lymphocytic infiltrates affecting the lungs, endocrine organs, such as pancreas and thyroid and skin, and increased lymphoid elements in lymph nodes and spleen. Although symptomatic therapy with immunosuppressive drugs provides some beneficial effects, the only curative treatment is hematopoietic stem cell transplantation.

Defective regulatory and effector T cell functions in patients with FOXP3 mutations

The autoimmune disease immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is caused by mutations in the forkhead box protein P3 (FOXP3) gene. In the mouse model of FOXP3 deficiency, the lack of CD4+ CD25+ Tregs is responsible for lethal autoimmunity, indicating that FOXP3 is required for the differentiation of this Treg subset. We show that the number and phenotype of CD4+ CD25+ T cells from IPEX patients are comparable to those of normal donors. CD4+ CD25high T cells from IPEX patients who express FOXP3 protein suppressed the in vitro proliferation of effector T cells from normal donors, when activated by "weak" TCR stimuli. In contrast, the suppressive function of CD4+ CD25high T cells from IPEX patients who do not express FOXP3 protein was profoundly impaired. Importantly, CD4+ CD25high T cells from either FOXP3+ or FOXP3- IPEX patients showed altered suppression toward autologous effector T cells. Interestingly, IL-2 and IFN-gamma production by PBMCs from IPEX patients was significantly decreased. These findings indicate that FOXP3 mutations in IPEX patients result in heterogeneous biological abnormalities, leading not necessarily to a lack of differentiation of CD4+ CD25high Tregs but rather to a dysfunction in these cells and in effector T cells.

IPEX and the role of Foxp3 in the development and function of human Tregs

Genetic defects in the transcription factor forkhead box protein P3 (Foxp3) cause immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX). IPEX is thought to be due to a defect in naturally arising CD4+ Tregs. In this issue of the JCI, Bacchetta and colleagues demonstrate that patients with IPEX and missense mutations in Foxp3 provide insight into the role of various domains of Foxp3 in the development and function of Tregs (see the related article beginning on page 1713).

Mechanistic associations of a mild phenotype of immunodysregulation, polyendocrinopathy, enteropathy, x-linked syndrome

BACKGROUND & AIMS

The syndrome of immunodysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is a rare disorder resulting in the expression of multiple autoimmune and allergic features. Early onset enteropathy and type 1 diabetes (T1D) are the most common clinical features. The IPEX syndrome is caused by mutations of the FOXP3 gene, which is essential for the development of regulatory T cells (Treg). We describe 2 unrelated patients with IPEX syndrome with a mild clinical phenotype and with novel FOXP3 mutations and the phenotypic and functional characterization of their Treg cells.

METHODS

The FOXP3 gene was analyzed by sequencing amplimers from genomic DNA. Treg cells were characterized by evaluating the number of CD4+CD25+ T cells and their functional ability to suppress the proliferation of autologous CD4+CD25- effector T cells stimulated with anti-CD3 and anti-CD28 antibodies.

RESULTS

A 7-year-old boy and a 24-year-old man presented with autoimmune enteropathy characterized by early onset persistent diarrhea not associated with T1D or other endocrinopathies. These 2 patients carry novel FOXP3 mutations that do not abrogate the function of the forkhead domain. They have normal numbers of CD4+CD25+ T lymphocytes, however, these show severely defective suppressive function in vitro.

CONCLUSIONS

Our 2 patients show that IPEX patients may present with early onset enteropathy and long-term survival without T1D or other endocrinopathies. This milder phenotype may be associated with FOXP3 mutations that do not abrogate the function of the forkhead domain.

X-linked immunodeficiencies

Recent advances in molecular genetics have allowed identification of at least seven genes involved in X-linked immunodeficiencies. This has resulted not only in improved diagnostic possibilities but also in a better understanding of the pathophysiology of these disorders. In some cases, mutations in the same gene have been shown to cause distinct clinical and immunologic phenotypes, demonstrating a strong genotype-phenotype correlation. Identification of the molecular basis of these diseases has permitted creation of disease-specific registries, with a better characterization of the clinical and immunologic features associated with the various forms of X-linked immunodeficiencies. Additionally, gene therapy has been attempted in X-linked severe combined immune deficiency (XSCID), with clear evidence of successful correction of the pathology, and the appearance of severe adverse effects.

Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked inheritance (IPEX), a syndrome of systemic autoimmunity caused by mutations of FOXP3, a critical regulator of T-cell homeostasis

Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked inheritance (IPEX) is one of a group of clinical syndromes that present with multisystem autoimmune disease suggesting a phenotype of immune dysregulation. Clinically, IPEX manifests most commonly with diarrhea, insulin-dependent diabetes mellitus, thyroid disorders, and eczema. FOXP3, the gene responsible for IPEX, maps to chromosome Xp11.23-Xq13.3 and encodes a putative DNA-binding protein of the forkhead family. Recent data indicate that FOXP3 is expressed primarily in the CD4+CD25+ regulatory T-cell subset, where it may function as a transcriptional repressor and key modulator of regulatory T-cell fate and function. This review describes the clinical features of IPEX and the structure, function, and known mutations of FOXP3 that provide important insights into its role in maintenance of immune homeostasis.

Infantile sialic acid storage disease and protein-losing gastroenteropathy

We report on a boy who presented at birth with gastroschisis and thereafter developed the characteristic clinical symptoms of infantile sialic acid storage disease within the first two months of life. Measurements of free sialic acid excretion (tenfold increase) in the urine and a 15-fold elevation of free sialic acid in cultured fibroblasts proved the diagnosis. The clinical course was complicated by hypertrophic cardiomyopathy, recurrent infections, hypothyroidism, and intestinal protein losses, which had never been described before in an infantile sialic acid storage disease patient. The child died at the age of 10 months. Clinical and laboratory findings are discussed and compared with other cases described in the literature.

Clinical and molecular features of the immunodysregulation, polyendocrinopathy, enteropathy, X linked (IPEX) syndrome

Immunodysregulation, polyendocrinopathy, enteropathy, X linked (IPEX, OMIM 304790) is a rare, recessive disorder resulting in aggressive autoimmunity and early death. Mutations in FOXP3 have been identified in 13 of 14 patients tested. Research in the mouse model, scurfy, suggests that autoimmunity may stem from a lack of working regulatory T cells. We review published reports regarding the genetics, clinical features, immunology, pathology, and treatment of IPEX. We also report three new patients who were treated with long term immunosuppression, followed by bone marrow transplantation in two. IPEX can be differentiated from other genetic immune disorders by its genetics, clinical presentation, characteristic pattern of pathology, and, except for high IgE, absence of substantial laboratory evidence of immunodeficiency. While chronic treatment with immunosuppressive drugs may provide temporary benefit for some patients, it does not cause complete remission. Remission has been observed with bone marrow transplantation despite incomplete engraftment, but the long term outcome is uncertain.

IPEX is a unique X-linked syndrome characterized by immune dysfunction, polyendocrinopathy, enteropathy, and a variety of autoimmune phenomena

The rare syndrome known as IPEX (OMIM: 304930) is characterized by immune-dysfunction, polyendocrinopathy, enteropathy, and X-linked inheritance. The gene responsible for IPEX maps to Xp11.23-q13.3, a region of the X chromosome that also harbors the Wiskott-Aldrich syndrome gene ( WASP ). IPEX syndrome results from mutations of a unique DNA binding protein gene, FOXP3. Mutations invariably impair the seemingly essential forkhead domain of the protein, which is uniquely located in the carboxyl terminus, affecting protein function. In this review, we describe the identification of IPEX as a unique X-linked syndrome, the clinical features of IPEX, mutations of the immune-specific FOXP3 DNA binding protein, and bone marrow transplantation as a potential cure for the syndrome, which is usually lethal within the first year of life in affected males.

X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome is the human equivalent of mouse scurfy

To determine whether human X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome (IPEX; MIM 304930) is the genetic equivalent of the scurfy (sf) mouse, we sequenced the human ortholog (FOXP3) of the gene mutated in scurfy mice (Foxp3), in IPEX patients. We found four non-polymorphic mutations. Each mutation affects the forkhead/winged-helix domain of the scurfin protein, indicating that the mutations may disrupt critical DNA interactions.

The immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX) is caused by mutations of FOXP3

IPEX is a fatal disorder characterized by immune dysregulation, polyendocrinopathy, enteropathy and X-linked inheritance (MIM 304930). We present genetic evidence that different mutations of the human gene FOXP3, the ortholog of the gene mutated in scurfy mice (Foxp3), causes IPEX syndrome. Recent linkage analysis studies mapped the gene mutated in IPEX to an interval of 17-20-cM at Xp11. 23-Xq13.3.

Early death in two sisters with Hennekam syndrome

We report on two sisters with facial anomalies, protein-losing enteropathy, and intestinal lymphangiectasia consistent with the diagnosis of Hennekam syndrome. Both patients had a number of other anomalies not previously described in this autosomal recessive disorder, i.e., primary hypothyroidism, hypertrophic pyloric stenosis, and an early fatal outcome. These cases support the autosomal recessive transmission and the expansion of the phenotype of the Hennekam syndrome.

Evaluation of intestinal permeability and gluten sensitivity in Soft-Coated Wheaten Terriers with familial protein-losing enteropathy, protein-losing nephropathy, or both

OBJECTIVE

To evaluate intestinal permeability and gluten sensitivity in a family of Soft-Coated Wheaten Terriers (SCWT) affected with protein-losing enteropathy (PLE), protein-losing nephropathy (PLN), or both.

ANIMALS

6 affected adult dogs.

PROCEDURE

Intestinal biopsy specimens, urine protein-to-creatinine ratio, serum concentrations of albumin and globulin, and concentration of alpha1-protease inhibitor in feces were evaluated before, during, and 13 weeks after daily administration of 10 g of gluten for 7 weeks. Eosinophils and lymphocytes-plasmacytes were enumerated in intestinal biopsy specimens. Intestinal permeability was evaluated before and during the sixth week of gluten administration via cellobiose-mannitol and chromium-EDTA absorption tests.

RESULTS

Serum globulin concentration decreased significantly after prolonged administration of gluten. Although not significant, there was an increase in lymphocytes-plasmacytes and a decrease in eosinophils in intestinal biopsy specimens. Furthermore, these counts were greater than those reported for clinically normal dogs. Gluten administration did not increase intestinal permeability.

CONCLUSIONS AND CLINICAL RELEVANCE

Daily administration of gluten was associated with a significant decrease in serum globulin concentration in SCWT affected with PLE or PLN, but other variables remained unchanged. Although enhanced wheat-gluten sensitivity may be one factor involved in the pathogenesis of PLE or PLN in SCWT, this syndrome does not appear to be the result of a specific sensitivity to gluten.

Familial protein-losing enteropathy and protein-losing nephropathy in Soft Coated Wheaten Terriers: 222 cases (1983-1997)

Records and pedigrees of Soft Coated Wheaten Terriers (SCWT) with protein-losing enteropathy (PLE) or protein-losing nephropathy (PLN) were studied retrospectively. Criteria for inclusion were defined based on analysis of blood (panhypoproteinemia for PLE, hypoalbuminemia for PLN) and urine (proteinuria for PLN) and histopathologic examination of tissue. Two hundred twenty-two affected dogs (female:male ratio = 1.6, P < .001) were clinically identified. Dogs were diagnosed with PLE earlier (P < .005; mean +/- SD age: 4.7+/-2.6 years, n = 76) than with PLN (6.3+/-2.0 years, n = 84) or with both diseases (5.9+/-2.2 years, n = 62). Clinical signs included vomiting, diarrhea, weight loss, pleural and peritoneal effusions, and less commonly thromboembolic disease. Dogs with PLE generally had panhypoproteinemia and hypocholesterolemia; intestinal lesions included inflammatory bowel disease, dilated lymphatics, and lipogranulomatous lymphangitis. Dogs with PLN generally had hypoalbuminemia, proteinuria, hypercholesterolemia, and azotemia; renal lesions typically showed chronic glomerulonephritis/glomerulosclerosis, and less commonly endstage renal disease. Dogs with combined PLE/PLN had intermediate mean values (P < .001) for serum total protein, albumin, globulin, and cholesterol but had a higher mean urine protein:creatinine ratio than did PLN dogs (P < .05); intestinal and renal lesions in these dogs were similar to those in the other groups. Two dogs had incidental mild renal dysplasia. Pedigree analysis from 188 dogs demonstrated a common male ancestor, although the mode of inheritance is unknown. Both PLE and PLN are common diseases in this small breed population. The prognosis is poor. Compared with previously reported intestinal and renal diseases in dogs, a new, distinctive familial predisposition for both PLE and PLN has been recognized in the SCWT breed.

Carbohydrate-deficient glycoprotein syndrome type Ib. Phosphomannose isomerase deficiency and mannose therapy

Phosphomannose isomerase (PMI) deficiency is the cause of a new type of carbohydrate-deficient glycoprotein syndrome (CDGS). The disorder is caused by mutations in the PMI1 gene. The clinical phenotype is characterized by protein-losing enteropathy, while neurological manifestations prevailing in other types of CDGS are absent. Using standard diagnostic procedures, the disorder is indistinguishable from CDGS type Ia (phosphomannomutase deficiency). Daily oral mannose administration is a successful therapy for this new type of CDG syndrome classified as CDGS type Ib.

Protein-losing gastroenteropathy with facial anomaly and growth retardation: a mild case of Hennekam syndrome

A 7-year-old boy with a peculiar face, protein-losing gastroenteropathy and growth retardation is reported. Although he has a face similar to those 5 cases reported previously by Hennekam et al. (Am J Med Genet 34:593-600, 1989) and Gabrielli et al. (Am J Med Genet 40:244-247, 1991), he is not mentally retarded nor does he have severe lymphedema. This patient seems to have a mild case of the Hennekam syndrome.

Autosomal recessive intestinal lymphangiectasia and lymphedema, with facial anomalies and mental retardation

We report on two male and two female relatives with intestinal lymphangiectasia; severe lymphedema of limbs, genitalia, and face; facial anomalies; seizures; mild growth retardation; and moderate mental retardation. Main facial anomalies are a flat face, flat nasal bridge, hypertelorism, small mouth, tooth anomalies, and ear defects. Their parents are consanguineous. This disorder probably is an hitherto undescribed autosomal recessive syndrome.

Congenital hepatic fibrosis combined with protein-losing enteropathy and recurrent thrombosis

Two siblings, suffering from recurrent thrombosis and protein-losing enteropathy are presented. Histopathological examination of the liver in one of the patients, who died of multiple thrombosis, showed changes characteristic of Congenital Hepatic Fibrosis. Coagulation studies in the second child revealed decreased antithrombin-III in plasma, which might have had pathogenetic implications for the thrombosis tendency seen in both patients.

Case report--pregnancy and intestinal lymphangiectasis (familial neonatal hypoproteinaemia)

A patient with a history of familial intestinal lymphangiectasis and exudative enteropathy was observed during 2 consecutive pregnancies. Normal pregnancy is compatible with the condition and pregnancy need not aggravate the disease.

D-2-hydroxyglutaric aciduria: case report and biochemical studies

A patient with protein-losing gastroenteropathy and egg allergy has been shown to have a previously unrecognized organic aciduria, D-2-hydroxyglutaric aciduria. The observations made are consistent with an inherited metabolic disorder in the catabolism of 5-aminolaevulinate possibly due to deficient activity of a specific D-2-hydroxyglutarate dehydrogenase.

Cytogenetic studies of a male with sporadic intestinal lymphangiectasia: 45,X/46,XY mosaicism with pseudo- and hyperdiploid subpopulations in cultured tissues

45,X/46,XY mosaicism was found in peripheral blood, bone marrow, and tissue cultures of an adult male with intestinal lymphangiectasia (IL). Turner phenotype was not present; his meiotic metaphase analysis was normak, and his dermatoglyphics resembled those of his family. Ten separate tissue culture lines from three biopsies of skin and thyroid gland contained 45,X cells (14.8 to 78.3%). Autosomal aneuploidy, resulting in pseudo- or hyperdiploidy, was also present in 4.3 to 41.6% of the cells. A hyperdiploid clone with a 47,X,+10,+18 karyotype was found in 22.6% of cells in one line. A second hyperdiploid clone with a 48,X,+2,+18,+18 karyotype occurred in 7.6% of cells from another line containing a total of 41.6% pseudo- and hyperdiploid cells. Such clonal abnormalities were not typical of tissue cultures from other patients done in our laboratory. Growth of our patient's tissue cultures was subnormal, and none proliferated beyond the fourth subculture. The significance of this observation remains to be determined. Our results do not allow us to conclude whether our patient's mosaicism of somatic tissues arose during embryogenesis, or whether it originated post-natally. The secondary immunodeficiency which occurs in IL may explain persistence of cells with unusual combinations of autosomal aneuploidy in our patient's tissues.