Pulmonary lymphangiectasia: diagnosis and clinical course

The Nutmeg Lung Pattern in a Fetus with Hypoplastic Left Heart Syndrome and Turner Syndrome

The "nutmeg lung pattern" on fetal magnetic resonance imaging (MRI) indicates pulmonary lymphangiectasia. This is associated with adverse outcomes, particularly in fetuses with congenital heart defects and impaired pulmonary venous return. Whereas lymphedema is common in fetuses with Turner syndrome, pulmonary lymphangiectasia is not. A 26-year-old woman presented with a fetus with hypoplastic left heart syndrome (HLHS) without restrictive atrial septum (RAS). The family declined amniocentesis, yet non-invasive prenatal testing showed an increased risk for Turner syndrome. The patient underwent a fetal MRI as part of a blinded research protocol. Postnatal echocardiogram confirmed the fetal echocardiographic findings without evidence of RAS. Norwood stage I palliation was performed at two days of age. Significant neonatal respiratory morbidity including pneumonia, diaphragmatic and vocal cord pareses and chylothorax occurred. Subsequent review of fetal MRI revealed a prominent thoracic duct and mild pulmonary lymphangiectasia. Turner syndrome was confirmed by genetic testing. After one month, the patient was discharged to her home hospital with respiratory support, which was discontinued a few weeks later. Respiratory problems continued, but the vocal cord paresis resolved over time. This is a unique case of a fetus with HLHS/non-RAS with mild fetal pulmonary lymphangiectasia, and significant neonatal respiratory morbidity, probably in part due to Turner syndrome. The infant survived the neonatal period and underwent uneventful Glenn surgery. The patient's tolerance to the total cavopulmonary connection (TCPC) procedure is yet to be seen. An MRI lymphography should precede it to assess residual lymphatic abnormalities and serve as baseline for post-TCPC changes.

Pulmonary Complications in Patients With Fontan Circulation: JACC Review Topic of the Week

The Fontan operation has resulted in significant improvement in survival of patients with single ventricle physiology. As a result, there is a growing population of individuals with Fontan physiology reaching adolescence and adulthood. Despite the improved survival, there are long-term morbidities associated with the Fontan operation. Pulmonary complications are common and may contribute to both circulatory and pulmonary insufficiency, leading ultimately to Fontan failure. These complications include restrictive lung disease, sleep abnormalities, plastic bronchitis, and cyanosis. Cyanosis post-Fontan procedure can be attributed to multiple causes including systemic to pulmonary venous collateral channels and pulmonary arteriovenous malformations. This review presents the unique cardiopulmonary interactions in the Fontan circulation. Understanding the cardiopulmonary interactions along with improved recognition and treatment of pulmonary abnormalities may improve the long-term outcomes in this growing patient population. Interventions focused on improving pulmonary function including inspiratory muscle training and endurance training have shown a promising effect post-Fontan procedure.

Prediction Model with External Validation for Early Detection of Postoperative Pediatric Chylothorax

Earlier diagnosis of chylothorax following pediatric cardiac surgery is associated with decreased duration of chylothorax. Pleural fluid testing is used to diagnosis chylothorax which may delay detection in patients who are not enterally fed at time of chylothorax onset. Our aim was to develop and externally validate a prediction model to detect chylothorax earlier than pleural fluid testing in pediatric patients following cardiac surgery. A multivariable logistic regression model was developed to detect chylothorax using a stepwise approach. The model was developed using data from patients < 18 years following cardiac surgery from Primary Children's Hospital, a tertiary-care academic center, between 2017 and 2020. External validation used a contemporary cohort (n = 171) from Lucille Packard Children's Hospital. A total of 763 encounters (735 patients) were analyzed, of which 72 had chylothorax. The final variables selected were chest tube output (CTO) the day after sternal closure (dichotomized at 15.6 mL/kg/day, and as a continuous variable) and delayed sternal closure. The highest odds of chylothorax were associated with CTO on post-sternal closure day 1 > 15.6 mL/kg/day (odds ratio 11.3, 95% CI 6,3, 21.3). The c-statistic for the internal and external validation datasets using the dichotomized CTO variable were 0.78 (95% CI 0.73, 0.82) and 0.84 (95% CI, 0.78, 0.9) and performance improved when using CTO as a continuous variable (OR 0.84, CI: 95% CI 0.80, 0.87). Using the models described, chylothorax after pediatric cardiac surgery may be detected earlier and without reliance on enteral feeds.

Recurrent pericardial effusion in a boy: A clue to underlying pericardial and pulmonary lymphangiectasia

Pulmonary lymphangiectasia is a rare congenital malformation of lymphatic vessels. We report the case of a 5-year-old boy with recurrent pericardial effusion which was diagnosed to be due to pericardial and pulmonary lymphangiectasia.

Peri-operative myocardial performance in infants with Down syndrome undergoing CHD repair

BACKGROUND

We aimed to characterise the impact of Down syndrome on myocardial performance and loading conditions in infants with Down syndrome and CHD over the peri-operative period by comparing them with infants matched for cardiac lesion with a normal microarray.

METHODS

Left ventricular global longitudinal strain, right ventricular free wall longitudinal strain, left ventricular end-systolic wall stress, and right ventricular systolic pressure were measured in the two groups over the peri-operative period.

RESULTS

Fifty-five infants had a diagnosis of Down syndrome and these were compared with 29 control infants. Left ventricular global longitudinal strain decreased in both groups post-operatively with the Down syndrome group demonstrating some recovery pre-discharge (18 ± 3 versus 16 ± 3 %, p = 0.01). Right ventricular longitudinal strain significantly decreased in both groups post-operatively with the control group demonstrating better recovery by hospital discharge (14 ± 4 versus 18 ± 6 %, p < 0.01). End-systolic wall stress was lower and right ventricular systolic pressure was higher in the Down syndrome group throughout the study period (all p < 0.05). Down syndrome was an independent predictor of the duration of ventilation, post-operative use of inotropes, and intensive care stay. Right ventricular longitudinal strain was an independent predictor of duration of intensive care stay.

CONCLUSION

This study demonstrates the difference between the two groups in relation to left and right ventricular function, particularly prior to discharge, and outlines the additional impact a diagnosis of Down syndrome has on myocardial performance during the peri-operative period.

Lymphatic Vessel Regression and Its Therapeutic Applications: Learning From Principles of Blood Vessel Regression

Aberrant lymphatic system function has been increasingly implicated in pathologies such as lymphedema, organ transplant rejection, cardiovascular disease, obesity, and neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. While some pathologies are exacerbated by lymphatic vessel regression and dysfunction, induced lymphatic regression could be therapeutically beneficial in others. Despite its importance, our understanding of lymphatic vessel regression is far behind that of blood vessel regression. Herein, we review the current understanding of blood vessel regression to identify several hallmarks of this phenomenon that can be extended to further our understanding of lymphatic vessel regression. We also summarize current research on lymphatic vessel regression and an array of research tools and models that can be utilized to advance this field. Additionally, we discuss the roles of lymphatic vessel regression and dysfunction in select pathologies, highlighting how an improved understanding of lymphatic vessel regression may yield therapeutic insights for these disease states.

Infants with Down syndrome and congenital heart disease have altered peri-operative immune responses

BACKGROUND

Infants with Down syndrome (DS) have an altered immune response. We aimed to characterise the inflammatory response in infants with DS and congenital heart disease (CHD) peri-operatively in comparison to infants with CHD and a normal chromosomal complement, and to healthy infants pre-operatively.

METHODS

Infants with DS/CHD, infants without DS but with CHD (CHD only) and healthy infants were prospectively recruited and serial serum cytokines evaluated peri-operatively using multiplex ELISA: tumour necrosis factor (TNF)-α and TNF-β; interferon (IFN)-γ, interleukin (IL)-1α, IL-2, IL-6, IL-8, IL-18, IL-1β, IL-10, and IL-1ra; vascular endothelial growth factor (VEGF); granulocyte macrophage colony-stimulating factor (GM-CSF); and erythropoietin (EPO).

RESULTS

Ninety-four infants were recruited including age-matched controls (n = 10), DS/CHD (n = 55), and CHD only (n = 29). Children with DS/CHD had significantly lower concentrations of several cytokines (IL-10, IL-6, IL-8, IL-1β, VEGF) in the pre- and post-operatively vs CHD only and controls. EPO and GM-CSF were significantly higher in DS/CHD (p value <0.05).

CONCLUSIONS

Children with DS/CHD had significantly lower concentrations of several cytokines compared to controls or children with CHD only. EPO and GM-CSF were significantly higher in children with DS/CHD. The assessment of the immune response may be suitable for the predictable clinical outcomes in these children.

IMPACT

This study demonstrated that children with Down syndrome (DS) and congenital heart disease (CHD) have significant alterations in pro-inflammatory and anti-inflammatory immune responses peri-operatively. These changes may contribute to adverse clinical outcomes, including sepsis, chylothorax, and autoimmunity. They may impact the pathogenesis and outcome post-operatively and long term in this population. Children with DS and CHD have significantly lower cytokine concentrations, increased EPO and GM-CSF, and decreased VEGF pre- and post-operatively. Assessing their inflammatory state peri-operatively may facilitate the development of a predictive model that can inform tailored management of these infants using novel therapies including immunomodulation.

Prognostic value of the nutmeg lung pattern/lymphangiectasia on fetal magnetic resonance imaging

BACKGROUND

A nutmeg lung pattern on magnetic resonance imaging (MRI) is an imaging finding associated with pulmonary lymphangiectasia. However, the prognostic value of the nutmeg lung pattern is unknown.

OBJECTIVE

To evaluate the clinical associations of nutmeg lung indicating lymphangiectasia on fetal lung MRI and its relationship with early mortality in fetuses with primary and secondary lymphangiectasia.

MATERIALS AND METHODS

We retrospectively identified all pregnant patients with a fetal MRI performed for indication of evaluating for pulmonary lymphangiectasia from 2006 to 2019. Two readers evaluated the fetal MRIs and interobserver agreement was calculated. Multivariable logistic regression models were performed to estimate the association of the echocardiographic findings and the presence of nutmeg lung. Kaplan-Meier and Cox regression analyses were performed to evaluate association with mortality in the first 30 days of life. Survival analysis was defined as mortality or orthotopic heart transplant at 30 days of age. P<0.05 was considered significant.

RESULTS

Our sample included 53 fetuses. Forty-seven (89%) had congenital heart disease (CHD) and 6 (11%) were diagnosed postnatally with primary lymphangiectasia. Interobserver agreement was 0.83. Pulmonary vein congestion on echocardiography was the strongest predictor of nutmeg lung (odds ratio [OR]=12.0, P=0.002). Ten fetuses reached the outcome of heart transplantation (n=1) or death (n=9) within the first 30 days of life. In fetuses with CHD, survival of those with nutmeg lung was significantly lower than in those without (P<0.001). Nutmeg lung was an independent risk factor for 30-day mortality (hazard ratio [HR]: 6.1, P=0.01).

CONCLUSION

Nutmeg lung pattern on fetal MRI is an independent risk factor associated with 30-day mortality in fetuses with CHD.

Imaging of fetal lymphangiectasias: prenatal and postnatal imaging findings

Lymphangiectasias are lymphatic malformations characterized by the abnormal dilation and morphology of the lymphatic channels. The classification and treatment of these disorders can be challenging given the limited amount of literature available in children. Various imaging modalities are used to confirm suspected diagnosis, plan the most appropriate treatment, and estimate a prognosis. Prenatal evaluation is performed using both prenatal US imaging and fetal MRI. These modalities are paramount for appropriate parental counseling and planning of perinatal care. During the neonatal period, chest US imaging is a useful modality to evaluate pulmonary lymphangiectasia because other modalities such as conventional radiography and CT display nonspecific findings. Finally, the recent breakthroughs in lymphatic imaging with MRI have allowed us to better classify lymphatic disorders. Dynamic contrast-enhanced lymphangiography, conventional lymphangiography and percutaneous lymphatic procedures offer static and dynamic evaluation of the central conducting lymphatics in children, with excellent spatial resolution and the possibility to provide treatment. The purpose of this review is to discuss the normal and abnormal development of the fetal lymphatic system and how to best depict it by imaging during the prenatal and postnatal life.

Diagnosis and Management of Lymphatic Disorders in Congenital Heart Disease

Purpose of Review

Lymphatic disorders have received an increasing amount of attention over the last decade. Sparked primarily by improved imaging modalities and the dawn of lymphatic interventions, understanding, diagnostics, and treatment of lymphatic complications have undergone considerable improvements. Thus, the current review aims to summarize understanding, diagnostics, and treatment of lymphatic complications in individuals with congenital heart disease.

Recent Findings

The altered hemodynamics of individuals with congenital heart disease has been found to profoundly affect morphology and function of the lymphatic system, rendering this population especially prone to the development of lymphatic complications such as chylous and serous effusions, protein-losing enteropathy and plastic bronchitis.

Summary

Although improved, a full understanding of the pathophysiology and targeted treatment for lymphatic complications is still wanting. Future research into pharmacological improvement of lymphatic function and continued implementation of lymphatic imaging and interventions may improve knowledge, treatment options, and outcome for affected individuals.

Congenital pulmonary lymphangiectasia in an extremely low birth weight: a case report

Objectives

Congenital pulmonary lymphangiectasia (CPL) is a rare but fatal disorder of the lung.

Case presentation

We describe the case of an extremely low birth weight (ELBW) infant who presented with severe respiratory distress and recurrent bilateral pneumothorax. He died on day 17. The post-mortem examination of the lungs showed numerous cystic spaces, ranging from 1 to 2 mm in size, in the visceral pleura, in the thickened interlobular septum and hilum. A diagnosis of primary CPL was made.

Conclusions

We intend to underline that CPL, albeit rare, must be one of the differential diagnoses in infants with severe neonatal respiratory distress not responding to intensive care. Chronic interstitial lung diseases are a challenging diagnostic clinical problem, which requires a multidisciplinary approach. Histological lung examination may be useful to demonstrate the presence of CPL.

Pediatric Interstitial (Diffuse) Lung Disease

Interstitial (diffuse) lung diseases in infants and children comprise a rare heterogeneous group of parenchymal lung disorders, with clinical syndromes characterized by dyspnea, tachypnea, crackles, and hypoxemia. They arise from a wide spectrum of developmental, genetic, inflammatory, infectious, and reactive disorders. In the past, there has been a paucity of information and limited understanding regarding their pathogenesis, natural history, imaging findings, and histopathologic features, which often resulted in enormous diagnostic challenges and confusion. In recent years, there has been a substantial improvement in the understanding of interstitial lung disease in pediatric patients due to the development of a structured classification system based on the etiology of the lung disease, established pathologic criteria for consistent diagnosis, and the improvement of thoracoscopic techniques for lung biopsy. Imaging plays an important role in evaluating interstitial lung diseases in infants and children by confirming and characterizing the disorder, generating differential diagnoses, and providing localization for lung biopsy for pathological diagnosis. In this chapter, the authors present the epidemiology, challenges, and uncertainties of diagnosis and amplify a recently developed classification system for interstitial lung disease in infants and children with clinical, imaging, and pathological correlation.

MR Imaging Evaluation of Pediatric Lymphatics:: Overview of Techniques and Imaging Findings

Recent advances in understanding lymphatic disorders have significantly improved noninvasive imaging of the lymphatic circulation, especially in pediatric patients. The ability to obtain high-quality MR imaging using 3-dimensional reconstruction has transformed the display of the lymph vessels and substantially enhanced the ability to diagnose various pediatric lymphatic disorders. Real-time dynamic imaging adds functional information to the assessment. MR imaging is increasingly used, not only to assess but also as a follow-up after lymphatic disorder treatment. This article discusses up-to-date imaging techniques and clinical applications of dynamic magnetic resonance lymphangiography for assessing central conducting lymphatic anomalies.

Pulmonary lymphangiectasis presenting as solitary pulmonary coin lesion

Pulmonary lymphangiectasis is a rare anomaly of infancy characterized by dilatation of pulmonary lymphatic vessels. It is considered to occur exclusively in young children and neonates, and pulmonary lymphangiectasis in asymptomatic adults is rare. Moreover, because chest radiography usually demonstrated the generalized congestive pattern of increased pulmonary vascularity or a reticulonodular pattern, it is extremely unusual for pulmonary lymphangiectasis to be demonstrated as a solitary nodular lesion. There were only two case reports of lymphangiectasis that developed as a nodular shadow in asymptomatic adults in English and Japanese literature. Here, we describe two cases of pulmonary lymphangiectasis that were demonstrated as solitary coin lesions in asymptomatic adults without any extrapulmonary manifestations. An 84-year-old male and a 48-year-old male were found to have a gradually increasing round pulmonary nodule. Chest computed tomography (CT) demonstrated a smooth round nodule on the lung surface, and video-assisted thoracoscopic wedge resection was performed. The nodule was a thin-walled cyst containing yellowish liquid. Histological examination of the resected lung demonstrated lymphangiectasis in the subpleural and interlobular connective tissue and no abnormal cell proliferation. Therefore, we considered that the pulmonary nodule had been formed as a result of local fluid collection in pulmonary lymphangiectasis.

Neonatal Lung Disorders: Pattern Recognition Approach to Diagnosis

OBJECTIVE

Lung disease is a common indication for neonates to require medical attention, and neonatal chest radiographs are among the most common studies interpreted by pediatric radiologists. Radiographic features of many neonatal lung disorders overlap, and it may be difficult to differentiate among conditions.

CONCLUSION

This review presents an up-to-date practical approach to the radiologic diagnosis of neonatal lung disorders, with a focus on pattern recognition and consideration of clinical history, patient age, and symptoms.

Diagnosis of secondary pulmonary lymphangiectasia in congenital heart disease: a novel role for chest ultrasound and prognostic implications

BACKGROUND

Secondary pulmonary lymphangiectasia is a complication of congenital heart disease that results from chronic pulmonary venous obstruction.

OBJECTIVES

We aimed to evaluate the performance of chest ultrasound (US) in diagnosing secondary pulmonary lymphangiectasia and to review the clinical course of children with secondary pulmonary lymphangiectasia.

MATERIALS AND METHODS

Chest US was performed on 26 children with hypoplastic left heart syndrome, total anomalous pulmonary venous connection or cor triatriatum in a prospective observational study. Thirteen children had pulmonary venous obstruction (62% male; median age: 17 days old, range: 1-430 days old) and 13 children did not have obstruction (62% male; median age: 72 days old, range: 4-333 days old). US features of secondary pulmonary lymphangiectasia were documented and diagnostic performance was determined. Clinical course of patients with secondary pulmonary lymphangiectasia was reviewed.

RESULTS

Eleven of 13 (84.6%) patients in the obstructed group had a clinical and/or biopsy diagnosis of secondary pulmonary lymphangiectasia. Statistically significant chest US criteria for diagnosis were presence of irregular lung surface (likelihood ratio [LR] 6.8, 95% confidence interval [CI] 1.9-25.1), subpleural cystic appearing structures (LR 3.6, 95% CI 1.2-10.7), and combination of subpleural cystic appearing structures and surface irregularity together (LR 10.9, 95% CI 1.6-75.0). Seven of 11 (63.6%) patients with secondary pulmonary lymphangiectasia died during follow-up, the majority due to cardiopulmonary failure or complications.

CONCLUSION

Chest US is an accurate and reproducible bedside method for diagnosing secondary pulmonary lymphangiectasia in patients with pulmonary venous obstruction. These patients may have worse prognoses.

Cystic Lung Disease in Down Syndrome: A Case Report and Literature Review

Subpleural lung cysts (SPC) are seen in children with Down syndrome (DS). The incidence and the long term course of these lesions are not known. It is important for pediatricians and pediatric radiologists to be aware of these lung lesions since the DS patients' longevity has increased and they have greater frequency to encounter the clinicians. Autopsy and the radiology series have shown that these lesions are often found in association with congenital heart disease, particularly the endocardial cushion defect and prematurity.

Nonmalignant Adult Thoracic Lymphatic Disorders

The thoracic lymphatic disorders are a heterogeneous group of uncommon conditions that are associated with thoracic masses, interstitial pulmonary infiltrates, and chylous complications. Accurate diagnosis of the thoracic lymphatic disorders has important implications for the newest approaches to management, including embolization and treatment with antilymphangiogenic drugs. New imaging techniques to characterize lymphatic flow, such as dynamic contrast-enhanced magnetic resonance lymphangiogram, are redefining approaches to disease classification and therapy.

Congenital generalized lymphangiectasia: a rare developmental disorder for non-immune fetal hydrops

Firstly described by Rudolf Virchow in the 19th century, congenital generalized lymphangiectasia is a rare entity characterized by dilation of lymphatic vessels, and was recently classified in primary or secondary lymphangiectasia. Generalized forms may be diagnosed during pre-natal follow-up with ultrasound examination, and, depending on its severity, the newborn outcome is very poor. The authors report the case of a female newborn with a previous diagnosis of fetal hydropsy who was born after a full-term gestation with respiratory failure due to bilateral voluminous pleural effusion and ascites. Physical examination also disclosed syndromic facies. Despite all efforts of the intensive supportive care, the patient died after 24 days of life. The autopsy findings were consistent with the diagnosis of congenital pulmonary lymphangiectasia. The authors call attention to this rare diagnosis in patients with cavitary effusion and respiratory insufficiency at birth.

A 42-Year-Old Woman With Abnormal Chest CT Scan and Chylous Ascites

A 42-year-old white woman presented to the pulmonary clinic for evaluation of abnormal chest imaging. Twenty years prior to presentation, she was noted to have an abnormal chest radiograph during a routine preemployment evaluation. A subsequent bronchoscopy was nondiagnostic. She was followed up with annual imaging, which demonstrated little or no progression of her disease. She remained symptom free throughout this period. A year before her visit to the pulmonary clinic, she developed abdominal discomfort and was found to have ascites. Subsequently, she underwent three paracenteses with analysis revealing chylous fluid. She was a nonsmoker without a history of exposures or travel.

Pediatric lymphangiectasia: an imaging spectrum

BACKGROUND

Lymphangiectasia is a rarely encountered lymphatic dysplasia characterized by lymphatic dilation without proliferation. Although it can occur anywhere, the most common locations are the central conducting lymphatics and the pulmonary and intestinal lymphatic networks. Recent advances in lymphatic interventions have resulted in an increased reliance on imaging to characterize patterns of disease.

OBJECTIVE

To describe the patient populations, underlying conditions, and imaging features of lymphangiectasia encountered at a tertiary pediatric institution over a 10-year period and correlate these with pathology and patient outcomes.

MATERIALS AND METHODS

We retrospectively reviewed the pathology database from 2002 to 2012 to identify patients with pathologically or surgically proven lymphangiectasia who had undergone cross-sectional imaging. Medical records were reviewed for patient demographics, underlying conditions, treatment and outcome.

RESULTS

Thirteen children were identified, ranging in age from 1 month to 16 years. Five had pulmonary lymphangiectasia, four intestinal and four diffuse involvement. Pulmonary imaging findings include diffuse or segmental interlobular septal thickening, pleural effusions and dilated mediastinal lymphatics. Intestinal imaging findings include focal or diffuse bowel wall thickening with central lymphatic dilation. Diffuse involvement included dilation of the central lymphatics and involvement of more than one organ system. Children with infantile presentation and diffuse pulmonary, intestinal or diffuse lymphatic abnormalities had a high mortality rate. Children with later presentations and segmental involvement demonstrated clinical improvement with occasional regression of disease. Three children with dilated central lymphatics on imaging underwent successful lymphatic duct ligation procedures with improved clinical course.

CONCLUSION

Lymphangiectasia is a complex disorder with a spectrum of presentations, imaging appearances, treatments and outcomes. Cross-sectional imaging techniques distinguish segmental involvement of a single system (pulmonary or intestinal) from diffuse disease and may show dilated central conducting lymphatics, which may benefit from interventions such as ligation or occlusion.

Severe primary pulmonary lymphangiectasis in a premature infant: management and follow up to early childhood

Primary pulmonary lymphangiectasis (PPL) is a rare congenital developmental abnormality of the lung with a generally poor prognosis. Only a limited number of patients with neonatal-onset PPL have been reported to survive. We present the case of a male preterm infant (gestational age 34 weeks 6 days) with histologically confirmed PPL, complicated by hydrops fetalis, bilateral hydrothorax (treated in utero with pleuro-amniotic shunts), and immediate respiratory distress at birth. He survived after extensive neonatal intensive care therapy and was discharged home at the age of 7 months. At last follow up he was 3 years 7 months old, still requiring assisted ventilation via tracheostomy, having recurrent episodes of wheezing and had mild global developmental delay. This case demonstrates that survival beyond the neonatal period is possible even with severe PPL but long-term morbidity may be relevant, and multidisciplinary management and close follow up are essential.

Congenital pulmonary lymphangiectasis

Congenital pulmonary lymphangiectasis (CPL) is a rare vascular malformation causing dilated lymph vessels and disturbed drainage of lymph fluid. Based on the pathogenesis and clinical phenotype it can be classified as primary or secondary CPL. Associated genetic syndromes with or without lymphedema, familial occurrence and gene mutations have been described. In utero, it may present as non-immune hydrops with pleural effusions. At birth neonates may have respiratory failure due to chylothorax and pulmonary hypoplasia, causing very high short term mortality rates. Other cases may become symptomatic any time later in childhood or even during adult life. CPL is usually diagnosed based on the combination of clinical signs, imaging and histological findings. Open-lung biopsy is considered the gold standard for the diagnosis of CPL. Treatment is primarily supportive featuring aggressive mechanical ventilation and the management of problems associated with congenital chylothorax including chest-drainage, medium-chain triglycerides (MCT) diet, and octreotide.

Treatment of congenital pulmonary lymphangiectasia using ethiodized oil lymphangiography

Historically, congenital pulmonary lymphangiectasia (CPL) has had poor treatment outcomes despite aggressive therapy. There are recent reports of ethiodized oil (Lipiodol) lymphangiography successfully treating lymphatic leakage in adults. In this report, we describe two infants with CPL complicated by chylothoraces successfully treated by instillation of ethiodized oil into the lymphatic system. Congenital atresia of the thoracic duct was demonstrated on the lymphangiogram in both patients before treatment. Both patients have shown good short-term outcomes without supplemental oxygen or fat restricted diets at 9 months of age. Ethiodized oil lymphangiography represents a new treatment modality for some patients with CPL.

Rare congenital pulmonary malformation with diagnostic challenging: congenital pulmonary lymphangiectasia, report of four autopsy cases and review of literature

Congenital pulmonary lymphangiectasia (CPL) is a rare congenital disorder that typically presents with intractable respiratory failure in the first few days of life. There is an association non-immun hydrops and CPL. In this study we reviewed four CPL cases between January 2006 and January 2014 among 684 fetal-pediatric autopsies. All cases were in the second trimester. In light microscopy there were marked dilatated channels in the subpleural -peribronchial-subseptal region of the lungs. The channels were lined with flattened cells which were expressing CD 31 and D2-40, negative for CD34. Although pulmonary interstitial emphysema (PIE) was considered an important differential diagnosis, a giant cell reaction surrounding the interstitial cystic lesions, a histological hallmark of PIE. CPL is characterized by dilatation of the pulmonary lymphatic vessels and occurs as a congenital anomaly. Noonan classified it into three groups. Primary developmental defect of pulmonary lymphatics is group 3. Group 3 is called also as CPL; normal regression of the connective tissue elements fails to occur after the 16th week of fetal life, associated with an aggressive clinical course, poor prognosis. In fetal autopsy examination CPL should be recognized if there is a fetus with pleural effusion, non-immune hydrops. There is no clinical evidence for CPL.

Pneumonectomy case in a newborn with congenital pulmonary lymphangiectasia

Congenital pulmonary lymphangiectasia (CPL) is a rare lymphatic pulmonary abnormality. CPL with respiratory distress has a poor prognosis, and is frequently fatal in neonates. We report a case of pneumonectomy for CPL in a newborn. An infant girl, born at 39 weeks' after an uncomplicated pregnancy, exhibited respiratory distress 1 hr after birth, which necessitated intubation and aggressive ventilator care. Right pneumonectomy was performed after her symptoms worsened. Histologic examination indicated CPL. She is currently 12 months old and developing normally. Pneumonectomy can be considered for treating respiratory symptoms for improving chances of survival in cases with unilateral CPL.

Pulmonary lymphangiectasia resulting from vascular endothelial growth factor-C overexpression during a critical period

RATIONALE

Lymphatic vessels in the respiratory tract normally mature into a functional network during the neonatal period, but under some pathological conditions they can grow as enlarged, dilated sacs that result in the potentially lethal condition of pulmonary lymphangiectasia.

OBJECTIVE

We sought to determine whether overexpression of the lymphangiogenic growth factor (vascular endothelial growth factor-C [VEGF-C]) can promote lymphatic growth and maturation in the respiratory tract. Unexpectedly, perinatal overexpression of VEGF-C in the respiratory epithelium led to a condition resembling human pulmonary lymphangiectasia, a life-threatening disorder of the newborn characterized by respiratory distress and the presence of widely dilated lymphatics.

METHODS AND RESULTS

Administration of doxycycline to Clara cell secretory protein-reverse tetracycline-controlled transactivator/tetracycline operator-VEGF-C double-transgenic mice during a critical period from embryonic day 15.5 to postnatal day 14 was accompanied by respiratory distress, chylothorax, pulmonary lymphangiectasia, and high mortality. Enlarged sac-like lymphatics were abundant near major airways, pulmonary vessels, and visceral pleura. Side-by-side comparison revealed morphological features similar to pulmonary lymphangiectasia in humans. The condition was milder in mice given doxycycline after age postnatal day 14 and did not develop after postnatal day 35. Mechanistic studies revealed that VEGF recptor (VEGFR)-3 alone drove lymphatic growth in adult mice, but both VEGFR-2 and VEGFR-3 were required for the development of lymphangiectasia in neonates. VEGFR-2/VEGFR-3 heterodimers were more abundant in the dilated lymphatics, consistent with the involvement of both receptors. Despite the dependence of lymphangiectasia on VEGFR-2 and VEGFR-3, the condition was not reversed by blocking both receptors together or by withdrawing VEGF-C.

CONCLUSIONS

The findings indicate that VEGF-C overexpression can induce pulmonary lymphangiectasia during a critical period in perinatal development.

Diffuse Lung Disease

Diffuse lung disease (DLD) comprises a diverse group of disorders characterized by widespread pulmonary parenchymal pathology and impaired gas exchange. While many of these disorders are categorized under the rubric of interstitial lung disease (ILD), some of these disorders involve the airspaces or peripheral airways in addition to, or rather than, the interstitium. Some of these disorders are present primarily in infancy or early childhood, while others that are prevalent in adulthood rarely occur in childhood. This chapter will review the classification of pediatric DLD and the characteristic imaging findings of specific disorders to facilitate accurate diagnosis and guide appropriate treatment of children with these disorders.

A Rare Case of Chylothorax due to Pulmonary Lymphangiectasia in a 7-Year-Old Boy

Pulmonary lymphangiectasia (PL) is a rare condition characterized by dilatation of the lymphatic vessels. Post-neonatal PL is usually associated with pleural effusion and should therefore be suspected in the presence of chylothorax. We describe a post-neonatal manifestation of PL in a 7-year-old boy presenting chylothorax. Radiological examinations included thorax X-ray, ultrasound, and computed tomography scans. After the failure of conservative management (maintenance of the chest tube, total parenteral nutrition, administration of somatostatin synthetic analogues) we performed a thoracoscopic massive ligation of the thoracic duct's collateral along with a lung biopsy. Histology was compatible with type 1 congenital pulmonary lymphangectasia. One month after surgery a thoracoscopic pleurodesis was required for persistent chylothorax. The boy is now doing well 1 year after surgery.

Congenital pulmonary lymphangiectasia: an unusual presentation of nonimmune hydrops in a preterm infant

Congenital pulmonary lymphangiectasia (CPL) is a rare developmental disorder of the lung. CPL can present antenatally as nonimmune hydrops with pleural effusions, which are frequently associated with polyhydraminos. CPL presents in the neonatal period with severe respiratory distress and can be complicated by chylothorax. Diagnosis is difficult, as radiographic findings are nonspecific. Lung biopsy is indicated in some severe cases to diagnose CPL. The majority of infants with this condition rarely survive the neonatal period and are often diagnosed at autopsy. The final diagnosis is confirmed histologically by lung biopsy or at postmortem. We report a rare case of CPL in a preterm female infant presenting with severe nonimmune Hydrops fetalis who survived the neonatal period, and report clinical follow-up to early childhood.

[Congenital pulmonary lymphangiectasis: an unusual cause of respiratory distress in neonates]

Congenital pulmonary lymphangiectasis (CPL) is a rare condition in neonates characterized by abnormal dilatation of the lymphatics draining the interstitial and subpleural spaces of the lungs. Diagnosis is difficult in the neonatal period because respiratory features and radiological findings are not specific of the disease. Definitive diagnosis of CPL can be made only by pathologic examinations. We report a case of a male near-term neonate presenting with severe respiratory distress at birth. The initial chest X-ray showed frosted glass-like infiltrates with air bronchogram suggesting a maternofetal infection or respiratory distress syndrome. The infant required mechanical ventilation and chest tube insertion for right then bilateral pneumothorax. The child died 15 days later in spite of optimal high-frequency ventilation, bilateral pneumothorax drainage, and hemodynamic support. Autopsy revealed features consistent with the diagnosis of CPL. Although CPL is very rare, we should be aware that it is a possible cause of severe unexplained respiratory distress in neonates.

Interstitial Lung Disease in Infants and Children: New Classification System with Emphasis on Clinical, Imaging, and Pathological Correlation

Interstitial lung diseases in infants and children comprise a rare heterogeneous group of parenchymal lung disorders, with clinical syndromes characterized by dyspnea, tachypnea, crackles, and hypoxemia. They arise from a wide spectrum of developmental, genetic, inflammatory, infectious, and reactive disorders. In the past, there has been a paucity of information and limited understanding regarding their pathogenesis, natural history, imaging findings, and histopathologic features, which often resulted in enormous diagnostic challenges and confusion. In recent years, there has been a substantial improvement in the understanding of interstitial lung disease in the pediatric patient, due to the development of a structured classification system based on etiology of the lung disease, established pathologic criteria for consistent diagnosis, and improvement of thoracoscopic techniques for lung biopsy. Imaging plays an important role in evaluating interstitial lung diseases in infants and children by confirming and characterizing the disorder, generating differential diagnoses, and providing localization for lung biopsy for pathological diagnosis. In this chapter, the authors present epidemiology, challenges and uncertainties of diagnosis, and amplify a recently developed classification system for interstitial lung disease in infants and children with clinical, imaging, and pathological correlation.

Children with genetic disorders undergoing open-heart surgery: are they at increased risk for postoperative complications?

OBJECTIVES

Children with congenital heart disease and genetic disorders may be at increased risk for postoperative mortality and morbidity compared with children with congenital heart disease alone. The aim of the present study was to determine differences in postcardiopulmonary bypass outcome between these two groups.

DESIGN

Prospective cohort study.

SETTING

Tertiary university children's hospital.

PATIENTS

We enrolled 211 infants (<1 yr) who underwent bypass surgery for congenital heart disease. Data on perioperative course were compared between infants with and without genetic disorders. Univariate analysis was followed by regression analysis to control for confounders.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We enrolled 148 infants without and 63 infants with a genetic disorder. The majority of infants with genetic disorders had trisomy 21 (n = 32), six had microdeletion 22q11, and 25 had other genetic disorders. There was no significant difference in mortality between infants with and without genetic disorders. An underlying genetic disorder was an independent risk factor for renal insufficiency (p = .003) and reintubation (p = .02). Trisomy 21 was an independent risk factor for chylothorax (p = .01) and sepsis (p = .05). The length of hospital stay was longer in infants with genetic disorders other than trisomy 21 compared with infants with trisomy 21 (p = .009).

CONCLUSIONS

Infants with congenital heart disease and genetic disorders are not at increased risk for postoperative mortality. However, a genetic disorder is a risk factor for reintubation and renal insufficiency, whereas infants with trisomy 21 have a higher risk of chylothorax and sepsis. Intensive care providers need to be aware of these differences in morbidity to improve management decisions and parental counseling.

Imaging of Childhood Interstitial Lung Disease

The aphorism that children are not little adults certainly applies for the imaging of interstitial lung disease. Acquiring motion-free images of fine pulmonary structures at desired lung volumes is much more difficult in children than in adults. Several forms of interstitial lung disease are unique to children, and some forms of interstitial lung disease encountered in adults rarely, if ever, occur in children. Meticulous attention to imaging technique and specialized knowledge are required to properly perform and interpret chest imaging studies obtained for the evaluation of childhood interstitial lung disease (chILD). This review will address technique recommendations for imaging chILD, the salient imaging findings in various forms of chILD, and the efficacy of imaging in the diagnosis and management of chILD.

Infants and Young Children with Children's Interstitial Lung Disease

Though interstitial lung disease (ILD) can occur at any age in children, disorders more common in infancy and young children have received increased attention as an important group that is disproportionally affected, linked to lung development and lung injury, and represents disorders not seen in adult ILD. Identifying those children with potential children's ILD (chILD) and establishing a specific chILD diagnosis has evolved and is critical for pediatric pulmonologists, neonatologists, radiologists, and pathologists to recognize. Specific disorders more common in infancy include diffuse developmental disorders, growth abnormalities, pulmonary interstitial glycogenosis, neuroendocrine cell hyperplasia of infancy, and surfactant mutation dysfunction mutations. The presentation, evaluation, treatment, and clinical course are discussed for each of these specific disorders and other categories less common in infants and young children are briefly mentioned. Resources for physicians and families are also reviewed.

Imaging of thoracic lymphatic diseases

OBJECTIVE

This review will focus on radiographic description of lymphangiomas, lymphangiohemangiomas, pulmonary lymphangiomatosis, lymphangiectasis, lymphangioleiomyomatosis, lymphatic dysplasia, and traumatic lymphatic injury.

CONCLUSION

Diseases of the thoracic lymphatic system have a wide variety of unique radiographic manifestations, all of which can be explained by the underlying pathophysiology and relationship to the normal distribution of lymphatics in the chest.

Outcome of children with pulmonary lymphangiectasis

Pulmonary lymphangiectasis (PL) is a very rare developmental defect of the lungs, which has previously been reported to have a very poor prognosis. However, recent reports have suggested improved outcomes, possibly as a result of advances in neonatal and pediatric intensive care medicine. We performed a retrospective study on the outcome of children with PL between 1990 and 2008 referred to our tertiary center. Seven patients with histologically proven PL were identified over the 18-year period. Six patients presented in the neonatal period and one patient at 7 months of age, all of them requiring intensive care treatment. Three neonatal patients required extracorporeal membrane oxygenation (ECMO). Six of the seven patients did not survive including all those who received ECMO. Two of the six non-survivors died of other causes than their underlying disease. The only survivor had an antenatal diagnosis of hydrops and required in utero chest drain insertion. Postnatally he was managed with maximal medical treatment for bilateral pleural effusions and persistent pulmonary hypertension. A 7-month follow-up showed this infant to be doing well. In conclusion overall the prognosis of congenital PL remains poor. The one survivor demonstrates that this condition is survivable with aggressive intervention and as current evidence suggests gradual improvement of symptoms may occur over time, and that maximal medical treatment remains warranted.

Congenital airway lesions and lung disease

Structural upper and lower airway disorders and parenchymal disorders are uncommon in pediatric practice, but many pediatricians will encounter them and be responsible for the ongoing care of these patients. Pediatricians need to be cognizant of these diagnoses because, even though management of these disorders generally lacks an evidence base, existing principles of good care surrounding accurate diagnosis, classifications of severity, judicious use of investigations, medication, and surgical approaches are essential to good outcomes.

Lymphatics in lung disease

The lymphatic circulation appears to be a vital component in lung biology in health and in disease. Animal models have established the role of the lymphatic circulation in neoplastic and inflammatory diseases of the lung, such as asthma and cancer, and allowed for the understanding of the molecular controls of lymphangiogenesis in normal lung development. Understanding the role of lymphatics in human lung disease appears likely to contribute to the understanding of the pathogenesis of disease and the development of novel therapeutic targets.

Recurrent pleural effusions in a neonate

Difficulty breathing is a common presenting complaint for infants in the emergency department (ED). Periodic breathing, respiratory or systemic infection, and congenital heart disease are common diagnoses in this age group. We report the case of a male neonate presenting to the ED on multiple occasions with respiratory distress and recurrent pleural effusions of unique origin. Unlike adult pleural effusions, pediatric effusions are most commonly exudative and of infectious origin. In neonates, acquired chylothorax secondary to surgery or trauma is the most common cause of symptomatic pleural effusions. Congenital chylothorax is a rare entity that has not been presented in the emergency medicine literature. This case illustrates the extremely rare ED presentation of congenital chylothorax and outlines an approach to pediatric pleural effusions.