Protein losing enteropathy: comprehensive review of the mechanistic association with clinical and subclinical disease states

Cytomegalovirus Duodenitis Causing Persistent Hypoalbuminemia and Ascites After Liver Transplantation

A 44-year-old male had persistent hypoalbuminemia and ascites after liver transplantation. Imaging of the liver and gastrointestinal system was normal. Urine examination was negative for proteinuria. A diagnosis of protein-losing enteropathy was suspected, and a duodenal biopsy was done. Duodenal biopsy was positive for cytomegalovirus (CMV). The patient improved with CMV treatment.

State-of-the-art imaging for children with central lymphatic disorders

Lymphatic imaging plays a crucial role in novel lymphatic interventions, offering valuable insights into central lymphatic drainage. Lymphatic system abnormalities may appear in various pediatric disorders, and accurate imaging is crucial for effective diagnosis and tailored therapeutic interventions. Traditional imaging modalities have offered valuable insights, but the demand for non-invasive, high-resolution techniques has fueled the development of innovative lymphatic imaging methods. In this review, we explore the state of the art in lymphatic imaging specifically within the context of pediatric surgery.

Waldmann's disease: Primary intestinal lymphangiectasia diagnosed by 99mTc-labeled albumin macroaggregate scintigraphy-A case report in an adult patient

Key Clinical Message

Rare yet significant, this case sheds light on the uncommon presentation of Waldmann's disease in adults, showcasing the diagnostic challenges it poses. A multidisciplinary approach, integrating clinical, endoscopic, histological, and radiological evaluations, is crucial for accurate diagnosis and management. Further research is needed to deepen our understanding of this complex disorder.

Abstract

Waldmann's disease, or primary intestinal lymphangiectasia, is a rare disorder characterized by protein-losing enteropathy due to dilation and leakage of intestinal lymphatic vessels. Although typically diagnosed in early childhood, we present a case of a 55-year-old male with a complex medical history. The patient's history included intestinal obstruction, multidrug-resistant pulmonary tuberculosis, and primary antiphospholipid syndrome. He presented with a 2-year history of chronic diarrhea, weight loss, and lower limb edema. Endoscopic and histological examination revealed scattered white spots in the duodenum and terminal ileum, indicative of intestinal lymphangiectasia. Nuclear medicine studies confirmed abnormal protein loss. The rarity of Waldmann's disease in adulthood and its association with other significant medical conditions pose diagnostic challenges. The distinct endoscopic and histological findings, coupled with scintigraphy results, contribute to a comprehensive understanding of this complex case. Differential diagnoses and management considerations are discussed. This case highlights the atypical presentation of Waldmann's disease in adulthood, emphasizing the importance of a multidisciplinary approach for accurate diagnosis and management. Further research is warranted to enhance our understanding of this uncommon disorder and its potential implications for patients with complex medical histories.

Eosinophilic gastritis and gluten-sensitive enteropathy manifested as hypoproteinemia and treated with omalizumab: a case report

BACKGROUND

Eosinophilic gastritis (EoG) has rarely been reported in conjunction with gluten-sensitive enteropathy (GSE). When this does occur, patients typically present with gastrointestinal symptoms. To our knowledge, hypoproteinemia has not been reported as the primary manifestation. Anti-IgE therapy, such as omalizumab, lowers eosinophil counts in the blood, lungs, and gut. Its efficiency in treating active EoG remain unknown.

CASE PRESENTATION

We report a 33-month-old boy with a history of food allergy and atopic dermatitis who developed recurrent edema, hypoproteinemia, and eosinophilia at the age of 14 months. The diagnoses of EoG and GSE were confirmed based on the clinical presentation and results of gastrointestinal biopsies and serological testing. Although prednisone and dietary intervention were initially effective, the boy developed prednisone-related facial swelling. After stopping prednisone, his symptoms relapsed. Subsequent treatment with omalizumab, combined with dietary intervention, showed good efficacy and safety.

CONCLUSIONS

To our knowledge, this is the first case of concurrent EoG and GSE that presented primarily with hypoproteinemia. We highlight the rare manifestations of these two diseases to raise clinical suspicion and prevent missed and delayed diagnoses. The pathogenesis of EoG is heterogeneous and complex. Omalizumab showed good efficacy, indicating that IgE-mediated processes may be involved in the pathogenesis of this patient's diseases.

Serum Albumin as Prognostic Marker for Older Adults in Hospital and Community Settings

Serum albumin, known for its multifaceted role in health, is hypothesized to serve as a prognostic marker for older adults, both in hospital and community settings. Nine studies were included in the review, revealing consistent associations between low serum albumin levels and increased mortality risk in hospitalized older individuals. In community settings, low serum albumin levels were linked to higher mortality rates compared to those with normal levels. The synthesis of evidence underscores the potential of serum albumin as a prognostic marker for older adults, offering valuable insights for risk stratification and targeted interventions. While robust evidence supports its utility in hospital settings, further research is warranted in community settings to address current limitations and enhance the applicability of serum albumin as a prognostic tool. This review merges existing knowledge of the prognostic significance of serum albumin in older adults across hospital and community settings. The findings emphasize the importance of serum albumin as a potential prognostic marker, urging continued research efforts to refine its application in diverse healthcare contexts and improve outcomes for the aging population.

Newfound features associated with Hennekam Syndrome (Intestinal Lymphangiectasia-Lymphedema-Intellectual-Disability Syndrome) complicated with comorbid Waldmann's Disease resulting in Celiac Disease

Key Clinical Message

Adequate evaluation of patients with Hennekam Syndrome (HS) is challenging for physicians, because of multi-organ involvement and complex pathophysiology. We report the first case in an African American with lymphedema, who developed protein-losing enteropathy (PLE) and was successfully diagnosed with HS from cause-and-effect complications by Waldmann's Disease (WD) and comorbid Celiac Disease (CD).

Abstract

As far as we know, this is the 51st case of HS worldwide and the first one in an African American. The examined patient met all diagnostic criteria for HS, suggesting a dysfunction in the development of the lymphatic system, with associated comorbidities including developmental delay, gastrointestinal pathologies, facial and hearing abnormalities, and cardiac defects. Primary intestinal lymphangiectasia (WD) is a consequence of HS, which ultimately results in PLE and worsening interstitial lymph buildup. Based on our findings, CD, a complication not yet reported in HS, may arise from WD. Other autoimmune diseases may be seen in HS: a previous report demonstrated positive anti-thyroid stimulating hormone antibodies in HS patients. We propose that in HS, increased interstitial lymph (WD, if intestinal) with protein loss induces TNF-α- and IL-6-mediated immune reactions in the affected visceral organs, causing autoimmune pathologies. The interstitial lymph fluid-induced TNF-α and IL-6-mediated immunopathogenic reactions lead to inflammation and subsequent destruction of the intestinal mucosa. The chronic inflammatory increase in TGF-β causes gastric mucosa hypertrophy, which results in gastric fold thickening. Eventually, wider tight junctions develop, increasing gastric mucosa permeability, and leading to gastropathy. Considering the examined patient's history of gastroenteritis and the literature stating that CD is a non-mucosal cause of gastropathy and PLE, it is suggested that sequelae of GI complications occur in a cause-and-effect chain in HS. HS results in WD, which causes CD, resulting in hypertrophic gastropathy and loss of parietal and chief cells, eventually leading to malabsorption and PLE (Figure 1). HS primarily affects various organs due to inflammatory-mediated damage and accumulation of lymph fluid. Other findings for HS include keratoconjunctivitis sicca (dry eye disease), fibrous lymphedema exhibiting lymphorrhea, chylous ascites, anemia, and parathyroid abnormalities. Immune impairment in HS predisposes patients to autoimmune disorders, therefore autoimmunity (CD) and WD are concomitant comorbidities of HS. HS-associated comorbidities are primarily due to inflammation and damage to immune cell transport or underlying health conditions affecting proper lymphatic function. However, it is suggested that HS mutations may disrupt the development of the lymphatic system leading to further complication. complications can be compound heterozygous, and there is a need for further research to identify nearby genes that can cause concomitant co-morbidity.

A Yet Unrecognized Cause of Unusually High Levothyroxine Replacement Dose: Protein-Losing Enteropathy

Background/Objective

Large amount of protein wasting such as in nephrotic syndrome is a rare cause of high levothyroxine (LT4) replacement dose requirement. A case has been reported here that demonstrates that protein-losing enteropathy is a novel and yet unrecognized cause of high LT4 replacement dose requirement.

Case Report

A 21-year-old man with congenital heart disease was found to have primary hypothyroidism and started LT4 replacement. His weight was approximately 60 kg. Nine months later, while he was taking LT4 100 μg daily, thyroid-stimulating hormone (TSH) level was >200 μIU/mL (normal range, 0.3-4.7 μIU/mL) and free thyroxine level was 0.3 ng/dL (normal range, 0.8-1.7 ng/dL). The patient had excellent medication compliance. LT4 dose was increased to 200 μg daily and then 200 and 300 μg every other day. Two months later, TSH level was 3.1 μIU/mL and free thyroxine level was 1.1 ng/dL. He did not exhibit malabsorption or proteinuria. His albumin levels had been low since the age of 18 years (mostly <2.5 g/dL). Stool α-1-antitrypsin levels and calprotectin levels were elevated on multiple occasions. Protein-losing enteropathy was diagnosed.

Discussion

As most circulating LT4 is protein-bound, loss of protein-bound LT4 due to protein-losing enteropathy is the most plausible cause of the large LT4 dose requirement in this case.

Conclusion

This case demonstrates that protein-losing enteropathy, through loss of protein-bound thyroxine, is a novel and yet unrecognized cause of high LT4 replacement dose requirement. In patients who require high LT4 dose for unclear reasons, albumin levels should be examined and protein wasting be suspected in those with low albumin levels.

Development and application of a simple pharmacokinetic model that quantitatively describes the distribution and elimination of the commonly measured proteins

Increased plasma concentrations of a variety of cellular enzymes (alanine transaminase, aspartate aminotransferase, alkaline phosphatase, amylase, etc.) are commonly used as routine screening tests for a range of conditions. An increased concentration usually is assumed to result from an increased rate of delivery to the plasma. Factors such as decreased metabolism or excretion or altered extravascular distribution usually are ignored. As a prelude to a detailed analysis of all the factors producing altered plasma enzyme levels, we have reviewed the relevant literature describing the pharmacokinetics (PK) of 13 of the commonly measured plasma proteins and developed a PK model that provides a simple physiological description of all the data. Our model starts with the general 3-compartment, 6-parameter system previously developed for albumin and interprets the fluxes in terms of unidirectional sieved protein convectional volume flows from the plasma to the two tissue compartments and equal lymph flows returning to the plasma. This greatly constrains the model such that each protein is characterized by only two adjustable parameters (plasma clearance and sieving factor). In addition to accurately fitting the plasma kinetics, the model can accurately describe the tissue and lymph protein PK. For example, it can describe the thoracic duct lymph protein concentration following an intravenous infusion or the plasma concentration following a subcutaneous tissue injection. This simple model provides a satisfactory framework for the PK of 12 of the 13 proteins investigated. The glycoprotein intestinal alkaline phosphatase is the exception, requiring the addition of a liver recycling compartment involving the asialoglycoprotein receptor.

Pharmacokinetics of biologics in gastric cancer

Gastric cancer (GC) remains one of the leading causes of cancer death worldwide despite improvements in therapeutic options. Several biologics have been investigated in patients with GC, including those approved in other solid tumors; however, the success rate of the pivotal trials that investigated these biologic molecules in GC remains low. Elevation in total clearance and a decrease in systemic pharmacokinetic (PK) exposure in GC compared with other indications have been observed in these biologics across different pathways. Achieving optimal exposure for patients with GC is an important factor in balancing risk and optimizing therapeutic benefit and thus maximizing chance of positive outcomes for pivotal trials. Therefore, in this review, we summarize the PK disposition of several molecules (e.g., anti-HER2, anti-VEGF, and anti-PD1) evaluated in GC and showed a consistent trend of lower drug exposure as compared to other solid tumors. We hypothesize that two possible mechanisms: (1) hyper-catabolism of endogenous and exogenous proteins due to cancer cachexia; and (2) gastric protein leakage due to local inflammation at the gastrointestinal tract may explain or partially explain the increase of clearance in patients with GC. Last, the potential implications of such findings on dose selection to optimize the benefit: risk profile for biologics in GC are also discussed.

Pathophysiology, Functional Assessment and Prognostic Implications of Nutritional Disorders in Systemic Amyloidosis

Gastrointestinal involvement is a common clinical feature of patients with systemic amyloidosis. This condition is responsible for invalidating gastrointestinal symptoms, a significant macro and micronutrient deficit, and is a marker of disease severity. Gastrointestinal involvement should be actively sought in patients with systemic amyloidosis, while its diagnosis is challenging in patients with isolated gastrointestinal symptoms. The nutritional status in systemic amyloidosis plays an essential role in the clinical course and is considered a significant prognostic factor. However, the definition of nutritional status is still challenging due to the lack of internationally accepted thresholds for anthropometric and biochemical variables, especially in specific populations such as those with systemic amyloidosis. This review aims to elucidate the fundamental steps for nutritional assessment by using clinical and instrumental tools for better prognostic stratification and patient management regarding quality of life and outcomes.

Prognostic nutritional index: A potential biomarker for predicting the prognosis of decompensated liver cirrhosis

Background

Prognostic nutritional index (PNI) is an independent predictor of the prognosis of various diseases. However, the prognosis value of PNI in patients with decompensated liver cirrhosis (DLC) remains unknown. The study aimed to investigate the prognostic significance of PNI in patients with DLC.

Methods

A total of 214 eligible patients were enrolled in the study's development cohort between January 2018 and March 2021. The clinical primary study endpoints were mortality at 3 and 6 months. Receiver operating characteristic (ROC) curve analysis was used to assess the PNI's prediction accuracy, and Youden's index was utilized to determine the PNI's optimal cut-off value. Moreover, based on the optimal cut-off value, patients were categorized into high and low PNI groups. Multivariate logistic regression analysis was used to determine independent risk factors for mortality, while the relationship between PNI and the risk of death was identified and demonstrated using restricted cubic splines (RCS). A validation cohort of 139 patients was to verify the predictive power of the PNI.

Results

In the development cohort, the mortality rate at 3 and 6 months were 10.3% (22) and 14.0% (30), respectively. The PNI had comparable predictive power with the MELD score at all follow-up endpoints. Decreased PNI was an independent predictor of adverse prognosis at all follow-up endpoints. The RCS revealed a linear correlation between PNI and the risk of death. We confirmed that lower PNI was an independent predictor of poor prognosis in the validation cohort.

Conclusion

The findings showed that lower PNI is an independent factor of poor outcomes and might be utilized as a potentially promising prognostic predictor in patients with DLC.

Mannose phosphate isomerase gene mutation leads to a congenital disorder of glycosylation: A rare case report and literature review

We report the case of a 2-year-old girl who was diagnosed with Mannose-6-phosphate isomerase-congenital disorder of glycosylation (MPI-CDG) and provide a review of the relevant literature. The young girl presented with recurrent unexplained diarrhea, vomiting, hypoproteinemia, and elevated liver transaminases. Whole-exome sequencing revealed that the patient had compound heterozygous mutations in the MPI gene (NM_0024). An exon 4 (c.455G > T, p.R152l) mutation was inherited from the mother and an exon 7 (c.884G > A, p.R295H) mutation from the father. One week after the start of mannose treatment, the vomiting and diarrhea symptoms disappeared completely and did not show any side effects. We also provide a brief review of the relevant literature. Including the present case, a total of 52 patients from hospitals across 17 countries were diagnosed with MPI-CDG. Age at disease onset ranged from birth to 15 years, with an onset under 2 years in most patients (43/50). Overall, patients presented with at least one or more of the following symptoms: chronic diarrhea (41/46), vomiting (23/27), hepatomegaly (39/44), hepatic fibrosis (20/37), protein-losing enteropathy (30/36), elevated serum transaminases (24/34), hyperinsulinemic-hypoglycemia (24/34), hypoalbuminemia (33/38), prolonged coagulation (26/30), splenomegaly (13/21), non-pitting edema (14/20), failure to thrive (13/36), portal hypertension (4/9), epilepsy (2/17), thrombosis (12/14), and abnormally elevated leukocytes (5). None of the patients was reported to have an intellectual disability (0/28). The majority of patients (26/30) showed clinical symptoms, and laboratory results improved after oral mannose administration. Our findings suggest that MPI-CDG should be considered in children with unexplained recurrent digestive and endocrine systems involvement, and gene examination should be performed immediately to obtain a definite diagnosis in order to begin treatment in a timely manner.

The genetics of monogenic intestinal epithelial disorders

Monogenic intestinal epithelial disorders, also known as congenital diarrheas and enteropathies (CoDEs), are a group of rare diseases that result from mutations in genes that primarily affect intestinal epithelial cell function. Patients with CoDE disorders generally present with infantile-onset diarrhea and poor growth, and often require intensive fluid and nutritional management. CoDE disorders can be classified into several categories that relate to broad areas of epithelial function, structure, and development. The advent of accessible and low-cost genetic sequencing has accelerated discovery in the field with over 45 different genes now associated with CoDE disorders. Despite this increasing knowledge in the causal genetics of disease, the underlying cellular pathophysiology remains incompletely understood for many disorders. Consequently, clinical management options for CoDE disorders are currently limited and there is an urgent need for new and disorder-specific therapies. In this review, we provide a general overview of CoDE disorders, including a historical perspective of the field and relationship to other monogenic disorders of the intestine. We describe the genetics, clinical presentation, and known pathophysiology for specific disorders. Lastly, we describe the major challenges relating to CoDE disorders, briefly outline key areas that need further study, and provide a perspective on the future genetic and therapeutic landscape.

Protein-losing Enteropathy as a Complication and/or Differential Diagnosis of Common Variable Immunodeficiency

As protein-losing enteropathy (PLE) can lead to hypogammaglobulinemia and lymphopenia, and since common variable immunodeficiency (CVID) is associated with digestive complications, we wondered if (1) PLE could occur during CVID and (2) specific features could help determine whether a patient with antibody deficiency has CVID, PLE, or both. Eligible patients were thus classified in 3 groups: CVID + PLE (n = 8), CVID-only (= 19), and PLE-only (n = 13). PLE was diagnosed using fecal clearance of α1-antitrypsin or 111In-labeled albumin. Immunoglobulin (Ig) A, G, and M, naive/memory B and T cell subsets were compared between each group. CVID + PLE patients had multiple causes of PLE: duodenal villous atrophy (5/8), nodular follicular hyperplasia (4/8), inflammatory bowel disease-like (4/8), portal hypertension (4/8), giardiasis (3/8), and pernicious anemia (1/8). Compared to the CVID-only group, CVID + PLE patients had similar serum Ig levels, B cell subset counts, but lower naive T cell proportion and IgG replacement efficiency index. Compared to the CVID-only group, PLE-only patients did not develop infections but had higher serum levels of IgG (p = 0.03), IgA (p < 0.0001), and switched memory B cells (p = 0.001); and decreased naive T cells (CD4⁺: p = 0.005; CD8⁺: p < 0.0001). Compared to the PLE-only group, CVID + PLE patients had higher infection rates (p = 0.0003), and lower serum Ig (especially IgA: p < 0.001) and switched memory B cells levels. In conclusion, PLE can occur during CVID and requires higher IgG replacement therapy dosage. PLE can also mimic CVID and is associated with milder immunological abnormalities, notably mildly decreased to normal serum IgA and switched memory B cell levels.

Small Intestinal Bacterial Overgrowth-Pathophysiology and Its Implications for Definition and Management

The concept of small intestinal bacterial overgrowth (SIBO) arose in the context of maldigestion and malabsorption among patients with obvious risk factors that permitted the small bowel to be colonized by potentially injurious colonic microbiota. Such colonization resulted in clinical signs, symptoms, and laboratory abnormalities that were explicable within a coherent pathophysiological framework. Coincident with advances in medical science, diagnostic testing evolved from small bowel culture to breath tests and on to next-generation, culture-independent microbial analytics. The advent and ready availability of breath tests generated a dramatic expansion in both the rate of diagnosis of SIBO and the range of associated gastrointestinal and nongastrointestinal clinical scenarios. However, issues with the specificity of these same breath tests have clouded their interpretation and aroused some skepticism regarding the role of SIBO in this expanded clinical repertoire. Furthermore, the pathophysiological plausibility that underpins SIBO as a cause of maldigestion/malabsorption is lacking in regard to its purported role in irritable bowel syndrome, for example. One hopes that the application of an ever-expanding armamentarium of modern molecular microbiology to the human small intestinal microbiome in both health and disease will ultimately resolve this impasse and provide an objective basis for the diagnosis of SIBO.

Multicompartment Dynamic Contrast Magnetic Resonance Lymphangiography in Diagnosis of Complicated Lymphatic Anomaly

Background: To describe the dynamic contrast magnetic resonance lymphangiography (DCMRL) findings of three patients with complicated lymphatic anomaly (CLA) and protein losing enteropathy. We further discuss the importance of a multicompartment (intrahepatic [IH], intramesenteric [IM], and intranodal [IN]) DCMRL in delineating central lymphatic flow pathologies. Methods and Results: This is a retrospective study of three patients-one adult and two children who individually underwent the three-compartment DCMRL, namely IN-DCMRL, IH-DCMRL, and IM-DCMCRL. Findings from the results of the DCMRL for these three patients were obtained from the medical records and compared. Using the multicompartment imaging modalities, chylous fluid leakage into the peritoneum was observed using IM-DCMRL and IH-DCMRL but not IN-DCMRL for one of the patients in the case series. In contrast, leakage of chyle into the mediastinum was noted using IN-DCMRL but not IH-DCMRL and IM-DCMRL on another patient in this case series. Conclusion: Owing to the variability in outlining lymphatic flow pathologies, multicompartment imaging gives a more global picture of individual conduction disorders, has the potential to improve clinical assessment, and in some cases leads to a diagnosis of the abnormality and thus provides a better understanding of lymphatic flow anomalies in patients with CLAs.

Screening for gastrointestinal and pancreatic diseases

Diagnosis of chronic gastrointestinal and pancreatic diseases is challenging because patients generally present with nonspecific symptoms, such as abdominal pain and chronic diarrhea, some of which can last for many years. Although stool assays are more sensitive than serum assays, the former has unique limitations that healthcare providers should be aware of. One algorithm to screen for chronic gastrointestinal and pancreatic issues is to perform stool testing to assess inflammatory, watery (osmotic) and malabsorptive conditions. This chapter will discuss several stool-based screening tests, the major disorders they screen for and clinical performance. Sections on assay and sample limitations are also included. Stool testing can provide valuable diagnostic, prognostic and treatment response information if both the laboratory and clinician understand the benefits and limitations of these assays.

Diagnostic dilemma in diagnosing rare cause of protein losing enteropathy: Waldmann's disease

Waldmann's disease, or primary intestinal lymphangiectasia, is an unusual cause of protein‐losing enteropathy primarily characterized by lymphopenia, hypoalbuminemia, and hypogammaglobulinemia. However, variable clinical presentations result dilemmas in diagnosis and effective management. We present a toddler diagnosed with Waldmann's disease managed with a high‐protein diet and medium‐chain triglyceride supplementation.

Gut–brain Axis: Impact of Intestinal Inflammation and Micronutrient Deficiency on Psychomotor Development and Cognitive Functions in Egyptian Children with UndernutritionGut–brain Axis: Impact of Intestinal Inflammation and Micronutrient Deficiency on Psychomotor Development and Cognitive Functions in Egyptian Children with Undernutrition

Cognitive impairment, growth faltering and stunting are pervasive in many countries. mostly causes are unknown. Role of intestinal inflammation in such cases should be minded especially in low- and middle-income countries. We assessed serum markers of inflammation, fecal markers of intestinal inflammation and serum micronutrients in cases with aged 1 to 10 years who suffer from moderate or severe malnutrition “weight-for-age z-score and height-for-age z- Score (WAZ or HAZ) less than -2 SD”. Cognitive abilities were assessed using Wechsler intelligence scale for preschool and school children, Bayley scale III. 55.6% of preschool cases were below average or had mild or moderate intelligence retardation while 24.5% of school cases and 5% of children below 2 years were below average regarding cognitive functions. Cases showed statistically significant reduction of vitamin D, zinc and iron as compared to control. Serum markers of inflammation (alpha 1- glycoprotein (a1-AGP), endotoxin core protein (EndoCAB)) and fecal markers of intestinal inflammation (alpha 1 antitrypsin (AAT) and neopterin (NEOP)) were significant higher in cases than controls. School children showed negative correlation between processing functions and( a1-AGP), positive correlation between perceptual reasoning and serum vitamin A. Children below 2 years, showed negative correlations between motor function and (AAT), (a1-AGP), tumor necrosis factor- alpha (TNF-a) and (EndoCAB), positive correlation between language and serum zinc. In conclusion, our study showed impaired neurocognitive and psychomotor functions in malnourished stunted children. Also, vitamins and minerals deficiency and increased markers of intestinal inflammation were observed in cases compared to healthy control.

Dynamic contrast-enhanced magnetic resonance lymphangiography

Lymphatic flow disorders include a broad spectrum of abnormalities that can originate in the lymphatic or the venous system. The development of these disorders is multifactorial and is most commonly associated with congenital heart diseases and palliative surgeries that these patients undergo. Central lymphatic disorders might be secondary to traumatic leaks, lymphatic overproduction, conduction abnormalities or lymphedema, and they can progress to perfusion anomalies. Several imaging modalities have been used to visualize the lymphatic system. However, the imaging of central lymphatic flow has always been challenging. Dynamic contrast-enhanced magnetic resonance lymphangiography (DCMRL) allows for visualization of central lymphatic flow disorders and has been recently applied for the assessment of plastic bronchitis, protein-losing enteropathy, chylothorax and chylopericardium, among other lymphatic disorders. The hepatic and mesenteric accesses are innovative and promising techniques for better identification and understanding of these abnormalities. The main objectives of this review are to discuss the physiology and anatomy of the lymphatic system and review the current uses of DCMRL in the diagnosis and management of lymphatic flow disorders.

Dynamic Contrast Magnetic Resonance Lymphangiography Localizes Lymphatic Leak to the Duodenum in Protein-Losing Enteropathy

OBJECTIVES

Protein-losing enteropathy (PLE) is a disorder of intestinal lymphatic flow resulting in leakage of protein-rich lymph into the gut lumen. Our primary aim was to report the imaging findings of dynamic contrast magnetic resonance lymphangiography (DCMRL) in patients with PLE. Our secondary objective was to use these imaging findings to characterize lymphatic phenotypes.

METHODS

Single-center retrospective cohort study of patients with PLE unrelated to single-ventricle circulation who underwent DCMRL. We report imaging findings of intranodal (IN), intrahepatic (IH), and intramesenteric (IM) access points for DCMRL.

RESULTS

Nineteen patients 0.3-58 years of age (median 1.2 years) underwent 29 DCMRL studies. Primary intestinal lymphangiectasia (PIL) was the most common referring diagnosis (42%). Other etiologies included constrictive pericarditis, thoracic insufficiency syndrome, and genetic disorders. IN-DCMRL demonstrated a normal central lymphatic system in all patients with an intact thoracic duct and localized duodenal leak in one patient (1/19, 5%). IH-DCMRL detected a duodenal leak in 12 of 17 (71%), and IM-DCMRL detected duodenal leak in 5 of 6 (83%). Independent of etiology, lymphatic leak was only visualized in the duodenum.

CONCLUSIONS

In patients with PLE, imaging via DCMRL reveals that leak is localized to the duodenum regardless of etiology. Comprehensive imaging evaluation with three access points can provide detailed information about the site of duodenal leak.

Protein-Losing Enteropathy in Crohn's Disease: Two Unusual Cases

Protein-losing enteropathy (PLE) occurs when protein losses throughout the gastrointestinal (GI) tract exceed the liver’s ability to produce new protein. This is a rare presentation of Crohn's disease and few reported cases of PLE related to Crohn’s exist in the literature. We describe two patients who presented with symptoms of PLE. After extensive diagnostic workup both were diagnosed with Crohn’s disease and managed with prednisone.

Diagnostic Challenge in a Patient Presenting with Ascites and Hypergammaglobulinemia

Ascites is defined as the accumulation of intra-peritoneal fluid that can be caused by several diseases. We described a 47-year-old female presenting with low serum-ascites albumin gradient (SAAG) and a markedly high level of serum globulin. Serum protein electrophoresis revealed an M spike in the gamma region. Other laboratory results showed a marked increase in aspartate aminotransferase and alanine aminotransferase and predominantly conjugated hyperbilirubinemia without a sign of dilatation of bile ducts from abdominal ultrasonography examination. Furthermore, the follow-up showed a positive result for the anti-nuclear antibody test. The patient was assessed with autoimmune hepatitis, and the cause of ascites was suggested from portal hypertension although the level of SAAG was low. The ascites condition got improved after salt restriction, diuretics treatment, and abdominal paracentesis. However, the patient passed away because of the intracranial hemorrhage as a result of prolonged INR and APTT due to liver failure.

SepA Enhances Shigella Invasion of Epithelial Cells by Degrading Alpha-1 Antitrypsin and Producing a Neutrophil Chemoattractant

Shigella spp. are highly adapted pathogens that cause bacillary dysentery in human and nonhuman primates. An unusual feature of Shigella pathogenesis is that this organism invades the colonic epithelia from the basolateral pole. Therefore, it has evolved the ability to disrupt the intestinal epithelial barrier to reach the basolateral surface. We have shown previously that the secreted serine protease A (SepA), which belongs to the family of serine protease autotransporters of Enterobacteriaceae, is responsible for the initial destabilization of the intestinal epithelial barrier that facilitates Shigella invasion. However, the mechanisms used by SepA to regulate this process remain unknown. To investigate the protein targets cleaved by SepA in the intestinal epithelium, we incubated a sample of homogenized human colon with purified SepA or with a catalytically inactive mutant of this protease. We discovered that SepA targets an array of 18 different proteins, including alpha-1 antitrypsin (AAT), a major circulating serine proteinase inhibitor in humans. In contrast to other serine proteases, SepA cleaved AAT without forming an inhibiting complex, which resulted in the generation of a neutrophil chemoattractant. We demonstrated that the products of the AAT-SepA reaction induce a mild but significant increase in neutrophil transepithelial migration in vitro. Moreover, the presence of AAT during Shigella infection stimulated neutrophil migration and dramatically enhanced the number of bacteria invading the intestinal epithelium in a SepA-dependent manner. We conclude that by cleaving AAT, SepA releases a chemoattractant that promotes neutrophil migration, which in turn disrupts the intestinal epithelial barrier to enable Shigella invasion. IMPORTANCE Shigella is the second leading cause of diarrheal death globally. In this study, we identified the host protein targets of SepA, Shigella's major protein secreted in culture. We demonstrated that by cleaving AAT, a serine protease inhibitor important to protect surrounding tissue at inflammatory sites, SepA releases a neutrophil chemoattractant that enhances Shigella invasion. Moreover, SepA degraded AAT without becoming inhibited by the cleaved product, and SepA catalytic activity was enhanced at higher concentrations of AAT. Activation of SepA by an excess of AAT may be physiologically relevant at the early stages of Shigella infection, when the amount of synthesized SepA is very low compared to the concentration of AAT in the intestinal lumen. This observation may also help to explain the adeptness of Shigella infectivity at low dose, despite the requirement of reaching the basolateral side to invade and colonize the colonic epithelium.

Epidemiology of sarcoidosis in northern Spain, 1999-2019: A population-based study

BACKGROUND

The incidence of sarcoidosis varies widely worldwide. The aim of this study was to estimate the incidence of sarcoidosis in a population-based cohort from northern Spain.

METHODS

Patients diagnosed with sarcoidosis at Marqués de Valdecilla University Hospital, corresponding to the central Cantabria that encompasses Santander city and the surroundings, between January 1999 and December 2019were assessed. The diagnosis of sarcoidosis was established according to ATS/ERS/WASOG criteria as follows: compatible clinical and radiological presentation, histopathologic confirmation, and exclusion of other granulomatous diseases. Demographic and clinical data were collected. The incidence of sarcoidosis between 1999-2019 was estimated by sex, age, and year of diagnosis.

RESULTS

A total of 234 patients were included, with a male/female ratio of 0.81. The mean age of the cohort at diagnosis was 48.43 ± 14.83 years and 129 (55.1%) were women. Incidence during the period of study was 3.58 per 100,000 populations (95% confidence interval: 3.13 - 4.07). No gender predominance was observed. An increase in age at diagnosis over time was found in the linear regression analysis. Thoracic affection was found in 180 patients (76.9%). Most common extra-thoracic areas affected were skin (34.2%), joints (30.8%) and eyes (15.4%).

CONCLUSIONS

The incidence of sarcoidosis estimated in this study was similar to that of other Mediterranean countries. No gender predominance was observed. Consistent with previous studies, male presented an incidence peak 10 years earlier than female. A second peak between ages 60-69 years was identified in both sexes.

Overview of Albumin Physiology and its Role in Pediatric Diseases

PURPOSE OF REVIEW

Albumin plays a critical role in a wide range of disease processes; however, the role of albumin in pediatric patients has not been well described. This article aims to review albumin physiology and kinetics in children, albumin's impact on pediatric diseases, and the utility of albumin as a predictor of clinical outcome.

RECENT FINDINGS

Hypoalbuminemia is seen in a wide range of conditions, including protein-losing enteropathy, hepatic synthetic failure, malnutrition, inflammatory states, and renal disease. While the impact of hypoalbuminemia has been more extensively studied in adult patients, there is a relative paucity of literature in the pediatric population. Hypoalbuminemia is a marker of poor outcome in critically ill children and those undergoing a wide range of medical interventions. Albumin infusions may be an effective therapy for fluid resuscitation and for patients with severe hypoalbuminemia.

Chronic intestinal failure and short bowel syndrome in Crohn’s disease

Chronic intestinal failure (CIF) is a rare but feared complication of Crohn’s disease. Depending on the remaining length of the small intestine, the affected intestinal segment, and the residual bowel function, CIF can result in a wide spectrum of symptoms, from single micronutrient malabsorption to complete intestinal failure. Management of CIF has improved significantly in recent years. Advances in home-based parenteral nutrition, in particular, have translated into increased survival and improved quality of life. Nevertheless, 60% of patients are permanently reliant on parenteral nutrition. Encouraging results with new drugs such as teduglutide have added a new dimension to CIF therapy. The outcomes of patients with CIF could be greatly improved by more effective prevention, understanding, and treatment. In complex cases, the care of patients with CIF requires a multidisciplinary approach involving not only physicians but also dietitians and nurses to provide optimal intestinal rehabilitation, nutritional support, and an improved quality of life. Here, we summarize current literature on CIF and short bowel syndrome, encompassing epidemiology, pathophysiology, and advances in surgical and medical management, and elucidate advances in the understanding and therapy of CIF-related complications such as catheter-related bloodstream infections and intestinal failure-associated liver disease.

ANCA-associated vasculitis with protein-losing enteropathy is characterized by hypocomplementemia

Protein-losing enteropathy (PLE) has been reported to be associated with various systemic autoimmune diseases. However, reports regarding PLE in ANCA-associated vasculitis (AAV) patients are limited. We herein aimed to describe the clinical characteristics of AAV with PLE. We conducted a retrospective chart review of patients who were diagnosed with AAV and who began treatment at the University of Tokyo Hospital between June 2003 and June 2020. Among 68 AAV patients, there were four patients (5.9%) with PLE, consisting of two patients with MPA, one patient with GPA, and one patient with EGPA. Clinical courses were described, and their data were compared with AAV patients without PLE. Demographic characteristics, disease activity, and the pattern of organ involvement were similar between patients with PLE and without PLE. Patients with PLE had hypocomplementemia more frequently than the patients without PLE (CH50 75.0% vs 1.8%, p < 0.001, C3 50.0% vs 1.8%, p = 0.01, C4 75.0% vs 3.5%, p = 0.001). Although hypoalbuminemia improved with immunosuppressive therapy for AAV, the improvement in hypoalbuminemia was slow in most cases. We also performed a systematic review on PLE associated with vasculitis. Thirteen reports were included, and Henoch-Schonlein Purpura patients with PLE also tended to have hypocomplementemia. In conclusion, PLE is a rare complication of AAV and complement system may associate with the mechanism of PLE.

Unusual presentation of Crohn's disease

A previously well 37-year-old woman attended the emergency assessment unit with symptoms of lethargy, breathlessness and peripheral oedema, whereby initial basic investigations revealed an iron deficiency anaemia and serum hypoalbuminaemia. The patient subsequently had multiple admissions to secondary care over a 2-year period due to worsening peripheral and central oedema. Investigations ruled out non-gastrointestinal causes of serum hypoalbuminaemia, such as renal, cardiac and hepatic failures. Gastrointestinal investigations later revealed raised faecal alpha-1 antitrypsin and small bowel ulceration on capsule endoscopy, with a histological diagnosis of Crohn's disease made after a small bowel wedge resection. This case describes the unusual presentation of Crohn's disease displaying symptoms primarily of protein-losing enteropathy, an uncommon and under-recognised consequence of inflammatory bowel disease. A review of current literature and the underlying pathophysiology for this rare condition are discussed, particularly in relation to Crohn's disease.

Gastrointestinal protein loss in children with portal hypertension

Portal hypertension increases pressure in lymphatic ducts, which may lead to gastrointestinal (GI) protein loss. Reports have shown that adults with portal hypertension had resolution of protein-losing enteropathy after transplantation; but studies in children are very limited. We therefore aimed to evaluate GI protein loss in children with portal hypertension and defined changes after liver transplantation. Children aged 3 months to 18 years with portal hypertension and the age-matched healthy controls were enrolled during August 2018 to September 2019. Random fecal alpha-1 antitrypsin measurements were obtained at the initial visit, 3 months later, 1 week before, and 3 months after liver transplantation (if applicable). One or more positive test (> 0.795 mg/dL) was interpreted as a positive result. We enrolled 76 children (n = 38 in each group) with a median age of 15.5 months (interquartile range [IQR], 11.2-41.7), female 51%, and 92% with biliary atresia in the portal hypertension group. We noted GI protein loss in 4/38 children (10.5%) with portal hypertension, while none in the controls (p = 0.11). We found no significant differences on the markers of severity of liver disease and serum albumin between patients with vs. the ones without GI protein loss (p > 0.05). After liver transplantation, 2/4 patients with GI protein loss had undetectable loss. We found that, in a small group of children, 10.5% with portal hypertension had notable GI protein loss without significant relationships with the severity of liver disease.

Serum cholinesterase as a prognostic biomarker for acute heart failure

AIMS

The association between serum cholinesterase and prognosis in acute heart failure (AHF) remains to be elucidated. We investigated the serum cholinesterase level at discharge from hospitalization for AHF and its association with clinical outcomes in patients with AHF.

METHODS AND RESULTS

Among 4056 patients enrolled in the Kyoto Congestive Heart Failure multicentre registry, we analysed 2228 patients with available serum cholinesterase data. The study population was classified into three groups according to serum cholinesterase level at discharge: low tertile (<180 U/L, N = 733), middle tertile (≥180 U/L and <240 U/L, N = 746), and high tertile (≥240 U/L, N = 749). Patients in the low tertile had higher tricuspid pressure gradient, greater inferior vena cava diameter, and higher brain natriuretic peptide (BNP) levels than those in the high tertile. The cumulative 1-year incidence of the primary outcome measure (a composite endpoint of all-cause death and hospitalization for HF) was higher in the low and middle tertiles than in the high tertile [46.5% (low tertile) and 31.4% (middle tertile) vs. 22.1% (high tertile), P < 0.0001]. After adjustment for 26 variables, the excess risk of the low tertile relative to the high tertile for the primary outcome measure remained significant (hazard ratio 1.37, 95% confidence interval 1.10-1.70, P = 0.006). Restricted cubic spline models below the median of cholinesterase demonstrated incrementally higher hazards at low cholinesterase levels.

CONCLUSIONS

Low serum cholinesterase levels are associated with congestive findings on echocardiography, higher BNP, and higher risks for a composite of all-cause death and HF hospitalization in patients with AHF.

The Consequence of Excessive Consumption of Cow's Milk: Protein-Losing Enteropathy with Anasarca in the Course of Iron Deficiency Anemia-Case Reports and a Literature Review

Cow's milk is a key component of a child's diet. While the consumption of even trace amounts can result in allergy to its proteins and/or hypolactasia, excessive cow's milk consumption can result in numerous health complications, including iron deficiency, due to the diet being improperly balanced. Although the incidence of iron deficiency has declined, it remains the most widespread nutritional deficiency globally and the most common cause of anemia. One rare consequence of anemia caused by iron deficiency is protein-losing enteropathy; however, the mechanisms of its development are unclear. The following manuscript, based on a literature review, presents two rare cases of children, a 16-month-old boy and a 2.5-year-old girl, who developed severe microcytic anemia, enteropathy with hypoalbuminemia, and anasarca as a result of excessive cow's milk consumption. It highlights the possible relationship between excessive consumption of cow's milk in children and severe iron deficiency anemia with accompanying hypoalbuminemia; it may also result in serious clinical conditions, even in children that do not demonstrate food hypersensitivity.

Protein-losing enteropathy as precursor of inflammatory bowel disease: a review of the literature

We report the case of a 63-year-old female patient with liver cirrhosis who presented with symptoms of severe hypoalbuminaemia and diarrhoea. After ruling out other causes of hypoalbuminaemia and confirmation of an elevated faecal α-1 antitrypsin clearance, the diagnosis of protein-losing enteropathy (PLE) could be established. Since PLE is a syndrome caused by various diseases, classified into erosive and non-erosive gastrointestinal diseases or lymphatic obstruction, an extensive work-up was necessary, establishing the final diagnosis of Crohn's disease.

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.

Primary intestinal lymphangiectasia in an adult patient: A case report and review of literature

BACKGROUND

Primary intestinal lymphangiectasia (PIL), first described in 1961, is a rare disorder of unknown etiology resulting in protein-losing enteropathy. The disease is characterized by dilatation and leakage of intestinal lymph vessels leading to hypoalbuminemia, hypogammaglobulinemia, and lymphopenia. Since the severity and location of lymph vessels being affected can vary considerably, the range of associated symptoms is wide from mild lower-limb edema to generalized edema, abdominal and/or pleural effusion, and recurrent diarrhea, among others. Although usually developing in early childhood, we present the case of a 34-year-old woman with PIL. Moreover, we performed a literature review systematically assessing clinical presentation, and provide a practical approach to facilitate diagnosis and therapy of PIL in adults.

CASE SUMMARY

Our patient presented with unspecific symptoms of abdominal discomfort, fatigue, nausea, and recurrent edema of the lower limbs. Interestingly, a striking collinearity of clinical symptoms with female hormone status was evident. Additionally, polyglobulia, hypoalbuminemia, hypogammaglobulinemia, and transient lymphocytopenia were evident. Due to suspicion of a bone marrow disease, an extensive diagnostic investigation was carried out excluding secondary causes of polyglobulinemia and hypoalbuminemia. The diagnosis of primary intestinal lymphangiectasia was established after 22 wk by histological analysis of biopsy samples obtained via enteroscopy. Consecutively, the patient was put on a high-protein and low-fat diet with medium-chain triglycerides supplementation leading to significant improvement of clinical symptoms until 2 years of follow-up.

CONCLUSION

PIL can be the reason for cryptogenic hypoalbuminemia, hypogammaglobulinemia, and lymphopenia in adulthood. Due to difficulty in correct diagnosis, treatment initiation is often delayed despite being effective and well-tolerated. This leads to a significant disease burden in affected patients. PIL is increasingly been recognized in adults since the majority of case reports were published within the last 10 years, pointing towards an underestimation of the true prevalence. The association with female hormone status warrants further investigation.

Role of Octreotide in Menetrier’s Disease: Case Report and Review of Literature

Menetrier’s disease (MD) is a rare disease characterized macroscopically by gastric rugae thickening and microscopically by foveolar hyperplasia with glandular atrophy, resulting in luminal protein loss. Different treatment strategies, including antibiotics, prednisone, octreotide, and monoclonal antibodies, have yielded varying degrees of success. Here, we present a rare complication of MD with a gastric outlet obstruction from a large adenoma. However, prior to this complication, dramatic clinical and laboratory improvements were observed after 12 months of treatment with subcutaneous octreotide. We also present a review of the literature for the role of octreotide in the treatment of MD.

Sjögren syndrome associated with protein-losing enteropathy: case-based review

The association between Sjögren's syndrome (SS) and protein-losing enteropathy (PLE) was scarcly reported. To analyze the clinical, therapeutic, and outcome characteristics of patients with SS and PLE and also to delineate the potential mechanisms and pathways connecting the gut to SS targeted organ's pathology. Systematic screening was conducted using PubMed/MEDLINE, LILACS, SciELO, Web of Science, and Cochrane, dating 1980 to 2020. SS and PLE were the key words. Eighteen patients with SS and PLE were summarized. The patient's ages ranged between 20 and 88 years, and only 4 were males. Primary SS was observed in most cases. Anti-Ro was detected in 100% of the cases while anti-La was reported in 64% of them. The clinical manifestations were protein loss, edema of the lower limbs, pleural effusion, ascites, facial edema, anasarca, diarrhea, and weight loss. Among these clinical manifestations, edema of the lower limbs was the most severe. Albumin concentration was 0.9-3.4 g/dL which increased to 2.8-4.3 g/dL after treatment. Small bowel biopsy was performed in all of the cases. Concerning the therapy, all the patients received systemic glucocorticoids. All of them improved. The period of onset of improvement ranged from 3 weeks to 36 months (an average of 3 months). The early diagnosis and appropriate therapy of PLE in patients with anti-Ro positive SS and who present edema, anasarca, or hypoalbuminemia is vital for a beneficial outcome. An excellent clinical improvement in all the cases was observed when treated early enough by cortico-therapy, thus preventing patient's deterioration, complications, and reducing morbidity and potential mortality.

Houwen R, Barshack I, Somech R, Nieuwenhuis EE, Sagi I, Raas-Rothschild A, Middendorp S, Shouval DS. 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.