Correlation between capsule endoscopy classification and CT lymphangiography of primary intestinal lymphangiectasia.

AIM: To investigate the correlation between capsule endoscopy (CE) classification of primary intestinal lymphangiectasia (PIL) and computed tomography (CT) lymphangiography (CTL). MATERIALS AND METHODS: A total of 52 patients with diagnosed PIL were enrolled. All patients were examined using CTL and small intestinal CE before surgery. CE assessments included the morphology, scope, colour, and size of lesions. CTL assessments included intestinal wall, lymphatic vessel dilatation, lymph fluid reflux, and lymphatic fistula. Patients were divided into three groups according to type diagnosed by CE, and the CTL characteristics were analysed among the groups. RESULTS: CE showed 15 patients with type I, 27 with II, and 10 with type III. Intestinal wall thickening was observed in 15 type I, 21 type II, and seven type III. Pericardial effusion was observed in only three type I patients; the difference among types was statistically significant (p=0.02). Abnormal contrast agent distribution in the intestinal wall and mesentery was observed in 15 type II patients, and the difference was significantly greater than that of types I and III (p=0.02). Abnormal contrast agent distribution in the abdominal cavity was observed in 12 type II, and the difference was statistically significant (p=0.03). CONCLUSION: The CE PIL classification reflects the extent and scope of intestinal mucosa lesions; CTL more systematically demonstrates abnormal lymphatic vessels or reflux, and its manifestations of PIL are related to the CE classification. The combination of CTL with CE is useful for accurately evaluating PIL, and provides guidance for preoperative assessment and treatment management of PIL patients.

Endoscopic classification and pathological features of primary intestinal lymphangiectasia.

BACKGROUND: The appearance of the intestinal mucosa during endoscopy varies among patients with primary intestinal lymphangiectasia (PIL). AIM: To classify the endoscopic features of the intestinal mucosa in PIL under endoscopy, combine the patients' imaging and pathological characteristics of the patients, and explain their causes. METHODS: We retrospectively analyzed the endoscopic images of 123 patients with PIL who were treated at the hospital between January 1, 2007 and December 31, 2018. We compared and analyzed all endoscopic images, classified them into four types according to the endoscopic features of the intestinal mucosa, and analyzed the post-lymphographic computed tomography (PLCT) and pathological characteristics of each type. RESULTS: According to the endoscopic features of PIL in 123 patients observed during endoscopy, they were classified into four types: nodular-type, granular-type, vesicular-type, and edematous-type. PLCT showed diffuse thickening of the small intestinal wall, and no contrast agent was seen in the small intestinal wall and mesentery in the patients with nodular and granular types. Contrast agent was scattered in the small intestinal wall and mesentery in the patients with vesicular and edematous types. Analysis of the small intestinal mucosal pathology revealed that nodular-type and granular-type lymphangiectasia involved the small intestine mucosa in four layers, whereas ectasia of the vesicular- and edematous-type lymphatic vessels largely involved the lamina propria mucosae, submucosae, and muscular layers. CONCLUSION: Endoscopic classification, combined with the patients' clinical manifestations and pathological examination results, is significant and very useful to clinicians when scoping patients with suspected PIL.

Extended phenotypes of PIEZO1-related lymphatic dysplasia caused by two novel compound heterozygous variants.

Defects in the PIEZO1 gene cause lymphatic dysplasia in an autosomal recessive manner, mostly by loss-of-function variants. Moreover, since 2019, the role of PIEZO1 in bone formation has been established, but there have been no PIEZO1-related cases presenting definite skeletal involvement to date. A 21-year-old male with primary lymphatic dysplasia had some other distinctive clinical features, including multiple fracture history during infancy, thoracolumbar scoliosis, short stature, and left-sided facial bone hypoplasia. We analyzed the whole exome of the patient and found two novel pathogenic variants of PIEZO1 in trans: a 93.7 kb heterozygous deletion (chr16:88,782,477-88,876,207; exon 1-50) and c.2858G>A (p.Arg953His). Sanger sequencing validated the deletion with breakpoints, and each variant was inherited from a different parent. This study presented an extremely rare case of a patient with lymphatic dysplasia caused by compound heterozygous variants of PIEZO1, along with additional clinical manifestations including several skeletal phenotypes.

Recurrent prenatal PIEZO1-related lymphatic dysplasia: Expanding molecular and ultrasound findings.

Generalized lymphatic dysplasia (GLD), characterized by lymphedema, lymphangiectasias, chylothorax, effusions, represents a recognized cause of fetal hydrops. We describe for the first time recurrent pregnancies showing different ultrasound presentations of lymphatic dysplasia. The first fetus displayed diffuse subcutaneous cysts and septations while the second one presented fetal hydrops. Exome sequencing results at 18 gestational weeks in the second pregnancy showed compound heterozygosity for two novel PIEZO1 variants, afterwards detected also in the first fetus and in the heterozygous parents. Both ultrasound and genetic findings expand the current knowledge of PIEZO1-related GLD. We suggest exome sequencing in hydropic fetuses with normal cytogenetics and in pregnancies with recurrent hydrops/lymphatic dysplasia.

Primary Intestinal Lymphangiectasia: Diagnostic Accuracy of 99mTc-Labeled Human Serum Albumin Nanocolloid SPECT/CT Before Biopsy.

Primary intestinal lymphangiectasia is an unusual cause of protein losing enteropathy due to either congenital malformation or obstruction of lymphatics of intestine. The disease can affect all or only a small part of the small intestine. Peripheral lymphedema may be associated. The diagnosis is based on endoscopic and histopathological findings. A 30-year-old woman presents lower extremity edema with hypoproteinemia, hypoalbuminemia, and hypogammaglobulinemia. Tc-labeled human serum albumin nanocolloid lymphoscintigraphy of the lower extremity demonstrated a dermal backflow in the right extremity consistent with lymphedema and an unusual ileal uptake on SPECT/CT. Diagnosis is confirmed on histopathological evaluation of biopsy of ileum.

A homozygous variant in growth and differentiation factor 2 (GDF2) may cause lymphatic dysplasia with hydrothorax and nonimmune hydrops fetalis.

The etiology of nonimmune hydrops fetalis is extensive and includes genetic disorders. We describe a term-born female neonate with late onset extensive nonimmune hydrops, that is, polyhydramnios, edema, and congenital bilateral chylothorax. This newborn was successfully treated with repetitive thoracocentesis, total parenteral feeding, octreotide intravenously and finally surgical pleurodesis and corticosteroids. A genetic cause seemed plausible as the maternal history revealed a fatal nonimmune hydrops fetalis. A homozygous truncating variant in GDF2 (c.451C>T, p.(Arg151*)) was detected with exome sequencing. Genetic analysis of tissue obtained from the deceased fetal sibling revealed the same homozygous variant. The parents and two healthy siblings were heterozygous for the GDF2 variant. Skin and lung biopsies in the index patient, as well as the revised lung biopsy of the deceased fetal sibling, showed lymphatic dysplasia and lymphangiectasia. To the best of our knowledge, this is the first report of an association between a homozygous variant in GDF2 with lymphatic dysplasia, hydrothorax and nonimmune hydrops fetalis.

Biallelic mutation of FBXL7 suggests a novel form of Hennekam syndrome.

Hennekam lymphangiectasia-lymphedema syndrome is an autosomal recessive disorder characterized by congenital lymphedema, intestinal lymphangiectasia, facial dysmorphism, and variable intellectual disability. Known disease genes include CCBE1, FAT4, and ADAMTS3. In a patient with clinically diagnosed Hennekam syndrome but without mutations or copy-number changes in the three known disease genes, we identified a homozygous single-exon deletion affecting FBXL7. Specifically, exon 3, which encodes the F-box domain and several leucine-rich repeats of FBXL7, is eliminated. Our analyses of databases representing >100,000 control individuals failed to identify biallelic loss-of-function variants in FBXL7. Published studies in Drosophila indicate Fbxl7 interacts with Fat, of which human FAT4 is an ortholog, and mutation of either gene yields similar morphological consequences. These data suggest that FBXL7 may be the fourth gene for Hennekam syndrome, acting via a shared pathway with FAT4.

Clinical Profile, Response to Therapy, and Outcome of Children with Primary Intestinal Lymphangiectasia.

OBJECTIVE: Intestinal lymphangiectasia (IL; primary or secondary) is an important cause of protein-losing enteropathy. We evaluated the clinicolaboratory profile, response to therapy, complications, and outcome of children with primary IL (PIL). METHODS: Consecutive children (≤18 years) diagnosed with PIL (clinical setting, typical small bowel histopathology, and exclusion of secondary causes) from 2007 to 2017 were evaluated. RESULTS: Twenty-eight children with PIL (16 boys, age at symptom onset-12 [1-192] months and at diagnosis 8 [1-18] years) were studied. Pedal edema (93%), chronic diarrhea (78.6%), and recurrent anasarca (64%) were the common presentations. Ascites, pleural, and pericardial effusion were seen in 64 (n-18; chylous-5, non-chylous-13), 18, and 18% cases, respectively. Hypoproteinemia, hypoalbuminemia, hypocalcemia, and lymphopenia were present in 82, 82, 75 and 39% cases, respectively. Duodenal biopsy established the diagnosis in 86% cases, while 14% required distal small bowel biopsies. Dietary therapy was given in all and 6 cases required additional therapy (octreotide-6, tranexamic acid-3, and total parenteral nutrition-1). Lymphedema (3/5 vs. 1/23), pleural effusion (4/5 vs. 1/23), and the need for additional therapy (4/5 vs. 2/23) were significantly more in patients with chylous ascites (n = 5) than those without chylous ascites (n = 23). Twenty-four cases in follow-up (39 [6-120] months) showed improvement; however, 8 required readmission (symptom recurrence-6 [25%], complication-2 [8.3%], Budd Chiari Syndrome-1, and abdominal B cell lymphoma-1). CONCLUSION: Presence of chylous ascites suggests severe disease in children with PIL. Majority of PIL children respond to dietary therapy; only 20% need additional therapy. Long-term follow-up is essential to monitor for symptoms relapse and complications.

hCALCRL mutation causes autosomal recessive nonimmune hydrops fetalis with lymphatic dysplasia.

We report the first case of nonimmune hydrops fetalis (NIHF) associated with a recessive, in-frame deletion of V205 in the G protein-coupled receptor, Calcitonin Receptor-Like Receptor (hCALCRL). Homozygosity results in fetal demise from hydrops fetalis, while heterozygosity in females is associated with spontaneous miscarriage and subfertility. Using molecular dynamic modeling and in vitro biochemical assays, we show that the hCLR(V205del) mutant results in misfolding of the first extracellular loop, reducing association with its requisite receptor chaperone, receptor activity modifying protein (RAMP), translocation to the plasma membrane and signaling. Using three independent genetic mouse models we establish that the adrenomedullin-CLR-RAMP2 axis is both necessary and sufficient for driving lymphatic vascular proliferation. Genetic ablation of either lymphatic endothelial Calcrl or nonendothelial Ramp2 leads to severe NIHF with embryonic demise and placental pathologies, similar to that observed in humans. Our results highlight a novel candidate gene for human congenital NIHF and provide structure-function insights of this signaling axis for human physiology.

Case report of primary intestinal lymphangiectasia diagnosed in an octogenarian by ileal intubation and by push enteroscopy after missed diagnosis by standard colonoscopy and EGD.

RATIONALE: Primary intestinal lymphangiectasia (PIL) is a rare, presumably congenital lesion that is usually diagnosed in patients < 3 years old, is rarely first diagnosed in adulthood, and when first diagnosed in adulthood typically presents with symptoms for many years. Although PIL is often identified by endoscopic abnormalities, it must be emphasized that the jejunoileum/distal duodenum must be intubated for diagnosis because the lesions are present in these regions. This work demonstrates that 1)-PIL can occur in an octogenarian; 2)-shows that the characteristic endoscopic findings are not found at colonoscopy without terminal ileal intubation; and 3)-may be missed at standard EGD without distal duodenal intubation. DIAGNOSES: A patient initially presented at age 83 with symptoms of watery diarrhea, abdominal distention, 5-Kg-weight-gain, and weakness for one month, and had typical clinical findings of PIL including chylous ascites, pleural effusions, bilateral pitting leg edema, hypoalbuminemia, borderline lymphopenia, hypovitaminosis-D, and hypocalcemia. Protein-losing-enteropathy was demonstrated by positive stool tests for alpha-1-antitrypsin. Standard colonoscopy revealed no significant lesions, but terminal ileal intubation during colonoscopy demonstrated creamy-white, punctate, mucosal lesions in terminal ileum, characteristic of lymphangiectasia. EGD with intubation to mid-descending duodenum revealed no significant lesions, but subsequent enteroscopy demonstrated lesions in distal duodenum/proximal jejunum similar to those in terminal ileum characteristic of lymphangiectasia. Histopathologic analysis of lesions of terminal ileum/distal duodenum demonstrated dilated mucosal vessels, confirmed as lymphatic vessels by immunohistochemistry. PIL was diagnosed after excluding secondary causes of intestinal lymphangiectasia. INTERVENTIONS/OUTCOMES: Patient placed on standard PIL diet: oral supplements of medium-chain triglycerides, a high protein diet, supplements of fat-soluble vitamins, and avoiding long-chain fatty acids, with marked clinical improvement. LESSONS: This work shows that: 1)-standard EGD and colonoscopy may miss characteristic lesions of PIL, 2)-enteroscopy or terminal ileal intubation at colonoscopy may be required for the diagnosis because lesions are typically located in distal duodenum/jejunoileum; and 3)-PIL can first present in the very elderly even with symptoms of short duration.

[Primary intestinal lymphangiectasia (Waldmann's disease)]. / Lymphangiectasies intestinales primitives (maladie de Waldmann).

Primary intestinal lymphangiectasia (PIL), Waldmann's disease, is a rare disorder of unknown etiology characterized by dilated intestinal lacteals leading to lymph leakage into the small-bowel lumen and responsible for protein-losing enteropathy leading to lymphopenia, hypoalbuminemia and hypogammaglobulinemia. PIL is generally diagnosed before 3 years of age but may be diagnosed in older patients. The main symptom is bilateral lower limb edema. Edema may be moderate to severe including pleural effusion, pericarditis or ascites. Protein-losing enteropathy is confirmed by the elevated 24-h stool α1-antitrypsin clearance and diagnosis by endoscopic observation of intestinal lymphangiectasia with the corresponding histology of biopsies. Videocapsule endoscopy may be useful when endoscopic findings are not contributive. Several B-cell lymphomas of the gastrointestinal tract or with extra-intestinal localizations were reported in PIL patients. A long-term strictly low-fat diet associated with medium-chain triglyceride and liposoluble vitamin supplementation is the cornerstone of PIL medical management. Octreotide, a somatostatin analog, have been proposed with an inconsistent efficacy in association with diet. Surgical small-bowel resection is useful in the rare cases with segmental and localized intestinal lymphangiectasia. A prolonged clinical and biological follow-up is recommended.

Dachsous1-Fat4 Signaling Controls Endothelial Cell Polarization During Lymphatic Valve Morphogenesis-Brief Report.

OBJECTIVE: The purpose of this study was to investigate the role of Fat4 and Dachsous1 signaling in the lymphatic vasculature. APPROACH AND RESULTS: Phenotypic analysis of the lymphatic vasculature was performed in mice lacking functional Fat4 or Dachsous1. The overall architecture of lymphatic vasculature is unaltered, yet both genes are specifically required for lymphatic valve morphogenesis. Valve endothelial cells (Prox1high [prospero homeobox protein 1] cells) are disoriented and failed to form proper valve leaflets. Using Lifeact-GFP (green fluorescent protein) mice, we revealed that valve endothelial cells display prominent actin polymerization. Finally, we showed the polarized recruitment of Dachsous1 to membrane protrusions and cellular junctions of valve endothelial cells in vivo and in vitro. CONCLUSIONS: Our data demonstrate that Fat4 and Dachsous1 are critical regulators of valve morphogenesis. This study highlights that valve defects may contribute to lymphedema in Hennekam syndrome caused by Fat4 mutations.

Primary intestinal lymphangiectasia: Multiple detector computed tomography findings after direct lymphangiography.

INTRODUCTION: To analyse the findings of multiple detector computed tomography (MDCT) after direct lymphangiography in primary intestinal lymphangiectasia (PIL). METHODS: Fifty-five patients with PIL were retrospectively reviewed. All patients underwent MDCT after direct lymphangiography. The pathologies of 16 patients were confirmed by surgery and the remaining 39 patients were confirmed by gastroendoscopy and/or capsule endoscopy. RESULTS: After direct lymphangiography, MDCT found intra- and extraintestinal as well as lymphatic vessel abnormalities. Among the intra- and extraintestinal disorders, 49 patients had varying degrees of intestinal dilatation, 46 had small bowel wall thickening, 9 had pleural and pericardial effusions, 21 had ascites, 41 had mesenteric oedema, 20 had mesenteric nodules and 9 had abdominal lymphatic cysts. Features of lymphatic vessel abnormalities included intestinal trunk reflux (43.6%, n = 24), lumbar trunk reflux (89.1%, n = 49), pleural and pulmonary lymph reflux (14.5%, n = 8), pericardial and mediastinal lymph reflux (16.4%, n = 9), mediastinal and pulmonary lymph reflux (18.2%, n = 10), and thoracic duct outlet obstruction (90.9%, n = 50). CONCLUSIONS: Multiple detector computed tomography after direct lymphangiography provides a safe and accurate examination method and is an excellent tool for the diagnosis of PIL.

Nutritional therapy and effect assessment of infants with primary intestinal lymphangiectasia: Case reports.

RATIONALE: Intestinal lymphangiectasia (IL) is a rare enteropathy involving the expansion and rupture of intestinal lymphatic channels. Although several reports have studied cases of primary IL (PIL), this condition is very rare, and is even less commonly encountered in infants. This study aimed to investigate the nutritional therapy and effect assessment of chylous reflux disorder caused by PIL in infants. PATIENT CONCERNS: Infantile patients were enrolled in the Affiliated Beijing Shijitan Hospital of the Capital Medical University between January 2012 and March 2014. The minimum age of onset was 4 months and the maximum age of onset was 16 months, with an average age of 4.9 months. DIAGNOSES: All children were inpatient who had been diagnosed with chylous reflux syndrome (chylothorax and/or chylic abdomen) caused by PIL. INTERVENTIONS: Retrospective analysis and individualized nutrition therapy of these cases were carried out. Finally, nutritional therapy and prognosis of PIL were assessed and summarized. OUTCOMES: All the children survived, showed improvement in the serum total protein, albumin, and HGB levels after nutritional therapy. After comprehensive nutritional therapy, we were able to achieve diarrhea control for all the 9 patients, and after treatment, the children passed soft, yellow stools 1 to 2 times/d. After treatment, the height and weight of all patients increased to within the normal ranges of the World Health Organization standard chart. The mean serum albumin level reached 41.3 g/L. All nutrition-related indicators were found to have significant improvement compared with the baseline levels. LESSONS: The results revealed that nutritional therapy for the 9 children with PIL was effective, and it may be able to improve the clinical syndromes and symptoms of children with PIL and promote recovery.

Lymphangiomatous Lesions of the Gastrointestinal Tract: A Clinicopathologic Study and Comparison Between Adults and Children.

OBJECTIVES: Lymphangiomatous lesions involving the gastrointestinal (GI) tract remain incompletely characterized, and their clinical and histopathologic features have not been systematically evaluated. The distinction between a primary lymphatic malformation (lymphangioma) and a dilation of existing lymphatics (lymphangiectasia) is of clinical significance, since lymphangiectasia may occur in the setting of lymphatic obstruction due to an unsampled malignancy. We describe clinical and morphologic features of lymphangiomas of the GI tract in adult and pediatric populations and contrast them with lymphangiectasia. METHODS: We performed a retrospective review of adult and pediatric lymphangiomas and lymphangiectasia involving the GI tract. RESULTS: Thirty-six cases of lymphangioma and lymphangiectasia were retrieved, and clinical presentation and histologic features were compared. Lymphangiomas had distinct clinical presentations in adults and children, with adult lesions being more frequently asymptomatic and more frequently involving the superficial mucosal layers of the GI tract. Microscopically, lymphangiomas mostly consisted of confluent dilated spaces with a smooth muscle component. This appearance differed from lymphangiectasia, which lacked a complete distinct endothelial or smooth muscle lining and diffusely involved the mucosa and submucosa. CONCLUSIONS: Morphologic features of GI tract lymphangiomas can be reliably distinguished from lymphangiectasia by clinical and pathologic characteristics.