Protein-losing enteropathy after fontan operation: investigations into possible pathophysiologic mechanisms

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Enteropathies of Infancy and Childhood

Intestinal biopsies constitute an ever-increasing portion of the pathologist's workload, accounting for nearly two-thirds of specimens accessioned yearly by the pathology department at The Children's Hospital of Philadelphia. The widespread use of endoscopy and gastrointestinal biopsies in current clinical practice presents the pathologist with a diversity of intestinal mucosal appearances corresponding to disease states of variable clinical severity, requiring close collaboration between clinician and pathologist for optimal interpretation. Many of the entities resulting in severe diarrhea of infancy have been recognized only in the last several decades, and although rare, the study of these disorders, especially when combined with the powerful methods of present-day genetics and molecular biology, has afforded important insights into enterocyte development and function, and intestinal immunity and tolerance. Other conditions once considered infrequent, such as celiac disease, have now been recognized to be much more common and can present with a wide range of pathologic features.

Protein-losing enteropathy: case illustrations and clinical review

Protein-losing enteropathy (PLE) is a rare syndrome of gastrointestinal protein loss that may complicate a variety of diseases. The primary causes can be divided into erosive gastrointestinal disorders, nonerosive gastrointestinal disorders, and disorders involving increased central venous pressure or mesenteric lymphatic obstruction. The diagnosis of PLE should be considered in patients with hypoproteinemia after other causes, such as malnutrition, proteinuria, and impaired protein synthesis due to cirrhosis, have been excluded. The diagnosis of PLE is most commonly based on the determination of fecal alpha-1 antitrypsin clearance. Treatment of PLE targets the underlying disease but also includes dietary modification, supportive care, and maintenance of nutritional status. In this article, cases illustrating a variety of clinical presentations and etiologies of PLE are presented, and its diagnostic approach and treatment are reviewed.

Clinical practice. Protein-losing enteropathy in children

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.

Reversal of protein-losing enteropathy after heart transplantation in young patients

Protein-losing enteropathy is a rare but life-threatening complication that occurs in some patients who develop intestinal lymphangiectasis secondary to increased systemic venous pressure. Although different forms of treatment have been tried, with varying results, the majority were reported to be unsuccessful. The aim of this study was to demonstrate that heart transplantation may be an appropriate therapeutic option for patients who do not respond to medical treatment. At our center, we performed heart transplantations in three patients with this condition. The mean follow-up period was 11+/-2 months. No patient died and the enteropathy regressed in all three.

Steroid pulse therapy for protein-losing enteropathy after the Fontan operation

A 19-year-old male with Fontan circulation developed protein-losing enteropathy associated with acute enteritis. Although his central venous pressure was in the normal range, subcutaneous high molecular heparin injection and oral predonisolone administration were not effective. We initiated intravenous high-dose methyl-predonisolone (15 mg/kg/day) for 3 days followed by oral predonisolone (0.5 mg/kg/day) for 4 days and repeated the course in 2 weeks. The serum protein and albumin increased to the normal level at 2 months after pulse therapy. The patient has not shown any recurrence of such protein-losing enteropathy for 2 years without any steroid agents.

[Medium-term management of protein-losing enteropathy of cardiac origin unresponsive to medical therapy in a patient awaiting heart transplantation]

Protein-losing enteropathy is characterized by excessive leaking of serum proteins into the gastrointestinal tract, as a result of disease progression in several diseases. We report the case of a 17-year-old-woman with hypoproteinemia, generalized edema and serosal effusions diagnosed as protein-losing enteropathy due to right ventricular failure secondary to previous surgical damage. All previously described therapies were ineffective in curing or relieving the disease or its symptoms, and the patient was listed for heart transplantation. During the 7-month period on the waiting list, the patient was managed as an outpatient, with fortnightly albumin infusions and intravenous furosemide administration, which allowed her a better quality of life during that period, avoiding further admissions.

An integrated approach to the care of adult patients with prior atriopulmonary Fontan surgery

Because of improved survival among children born with heart disease, more adults than children are now living with congenital heart defects, providing a new challenge for ongoing evaluation and care. At Children's Memorial Hospital in Chicago, we have gained extensive expertise in the long-term outcome of patients with repaired single ventricle anatomy, particularly with regard to arrhythmias and impaired hemodynamics, and have developed an integrated approach to their care. This article will summarize (a) single ventricle physiology, (b) evolution of the Fontan operation and the long-term multi-system sequelae, (c) treatment options for patients with prior Fontan surgery, focusing on Fontan conversion with arrhythmia surgery, and (d) unique management of adult patients with prior Fontan surgery. For the foreseeable future, pediatric nurse practitioners will have an important role, including coordination of care and providing continuity in the care of adults with prior Fontan surgery.

Protein-losing enteropathy after Fontan operation

Protein-losing enteropathy (PLE) is a poorly understood and enigmatic disease process affecting patients with single ventricle after Fontan operation. In those afflicted, PLE after Fontan operation results in significant morbidity and mortality. The pathophysiology of the disease is unknown; however, a proposed mechanism incorporates a combination of phenomena including: (1) altered hemodynamics, specifically low cardiac output; (2) increased mesenteric vascular resistance; (3) systemic inflammation; and (4) altered enterocyte basal membrane glycosaminoglycan make-up. A paradigm for the clinical management of PLE after Fontan operation is proposed.

Role of caval venous manipulation in treatment of protein-losing enteropathy

Protein-losing enteropathy has been associated with the Fontan operation, restrictive cardiomyopathy, constrictive pericarditis, tricuspid valvar stenosis and insufficiency, and superior caval venous obstruction. The mechanism of development of this complication of cardiac disease likely is multifactorial. We report here our experience with 3 patients with protein-losing enteropathy. Two had superior caval venous occlusion. The third patient had undergone an extracardiac Fontan operation, with stenosis of the extracardiac conduit placed to the right pulmonary artery. In all three cases, the complication was resolved by restoring unobstructed flow of blood in the superior or inferior caval vein. Since the aetiology of protein-losing enteropathy associated with cardiac disease is multifactorial, reduction of pressure in the tributaries of the superior caval vein may, in some cases, be curative. It is more difficult to cure the problem when it is associated with the Fontan operation.

Heparan sulfate and syndecan-1 are essential in maintaining murine and human intestinal epithelial barrier function

Patients with protein-losing enteropathy (PLE) fail to maintain intestinal epithelial barrier function and develop an excessive and potentially fatal efflux of plasma proteins. PLE occurs in ostensibly unrelated diseases, but emerging commonalities in clinical observations recently led us to identify key players in PLE pathogenesis. These include elevated IFN-gamma, TNF-alpha, venous hypertension, and the specific loss of heparan sulfate proteoglycans from the basolateral surface of intestinal epithelial cells during PLE episodes. Here we show that heparan sulfate and syndecan-1, the predominant intestinal epithelial heparan sulfate proteoglycan, are essential in maintaining intestinal epithelial barrier function. Heparan sulfate- or syndecan-1-deficient mice and mice with intestinal-specific loss of heparan sulfate had increased basal protein leakage and were far more susceptible to protein loss induced by combinations of IFN-gamma, TNF-alpha, and increased venous pressure. Similarly, knockdown of syndecan-1 in human epithelial cells resulted in increased basal and cytokine-induced protein leakage. Clinical application of heparin has been known to alleviate PLE in some patients but its unknown mechanism and severe side effects due to its anticoagulant activity limit its usefulness. We demonstrate here that non-anticoagulant 2,3-de-O-sulfated heparin could prevent intestinal protein leakage in syndecan-deficient mice, suggesting that this may be a safe and effective therapy for PLE patients.

Successful Surgical Treatment of Protein-Losing Enteropathy Complicating Rheumatic Tricuspid Regurgitation

Protein-losing enteropathy may uncommonly complicate cardiac disease. While well described as a complication for patients having undergone previous Fontan surgery for congenital heart disease, pericardial and valvular aetiologies are much less frequent. We report a 35-year-old female presenting with marked hypoalbuminaemia and peripheral oedema on a background of known rheumatic valvular heart disease. After extensive investigation for gastrointestinal, hepatic and renal causes of protein loss, echocardiography demonstrated severe tricuspid valve incompetence. Subsequent invasive testing confirmed severe tricuspid valve regurgitation in the absence of pericardial constriction. The patient proceeded to tricuspid valve repair with resolution of the protein-losing state and correction of hypoalbuminaemia. While cardiac causes of gastrointestinal protein loss are uncommon, they should be considered when initial diagnostic work up is negative. The importance of correction of haemodynamic precipitants of protein-losing enteropathy is also discussed.

Usefulness of heparin therapy in protein-losing enteropathy associated with single ventricle palliation

This retrospective study was designed to evaluate the effectiveness of subcutaneous heparin therapy for the treatment of protein-losing enteropathy (PLE) associated with single-ventricle palliation and to evaluate the side effects of long-term heparin use. PLE affects 4% to 13% of Fontan operative survivors. Five-year survival after onset of PLE is only 46% to 59%. We studied a cohort of patients with single-ventricle palliation who developed PLE and were treated with subcutaneous heparin. Seventeen patients were included in the study. Symptoms of PLE appeared on average 43 months after surgical palliation. At diagnosis of PLE, mean albumin level was 2.0 +/- 0.4 g/dl. At cardiac catheterization, mean systemic venous pressure was 11.6 mm Hg. Subjective symptomatic improvement on heparin therapy occurred in 13 patients (76%). Three patients (18%) went into clinical remission. Compared with the period before initiation of heparin, there was no significant difference in the number of hospital admissions (p = 0.99) or albumin infusions (p = 0.88) during the first year of heparin therapy. Five patients had x-rays of their thoracolumbar spine, and 9 patients had bone mineral analyses; all scans were grossly abnormal. In conclusion, subcutaneous heparin therapy leads to subjective improvement of PLE symptoms in most patients; however, it does not change the need for frequent albumin infusions and does not increase the rate of remission above that for standard medical therapy.

Clinical relevance of measurement of brain natriuretic peptide and N-terminal pro-brain natriuretic peptide in pediatric cardiology

BACKGROUND

The aim of this review is to understand the clinical usefulness of Brain Natriuretic Peptide (BNP) and N-terminal pro-Brain Natriuretic Peptide (NT-proBNP) in pediatric cardiology.

METHODS

A computerized literature search on National Library of Medicine using the keywords "BNP assay" and "NT-proBNP assay" was performed. Then, we refined the analysis to include only the studies specifically designed to evaluate the clinical usefulness of BNP and NT-proBNP assays in patients with congenital heart disease.

RESULTS

BNP and NT-proBNP are useful marker for diagnosis of heart failure, for the assessment of clinical severity and for the follow-up of congenital and pediatric heart diseases. However, results from different studies are often partial and not always univocal. Moreover, reference intervals in pediatric population have not yet been extensively evaluated.

CONCLUSIONS

BNP and NT-proBNP may be considered helpful markers for the integrated diagnosis and management of pediatric patients, though further studies are needed to support their routine use.

Resolution of protein-losing enteropathy and normalization of mesenteric Doppler flow with sildenafil after Fontan

A 9.5-year-old girl after Fontan procedure for hypoplastic left heart syndrome had recurrent protein-losing enteropathy (PLE) develop 2 months after partial catheter closure of the Fontan fenestration. Despite satisfactory hemodynamic measurements under general anesthesia, we postulated that she suffered from increased pulmonary vascular reactivity and commenced her on Sildenafil treatment. After 6 weeks of oral Sildenafil treatment, her serum albumin and the fecal alpha-1-antitrypsin levels normalized, and her exercise tolerance had increased. There was also an improvement of the mesenteric arterial flow patterns on Doppler studies. Sildenafil should be considered in the treatment of PLE after the Fontan procedure.