Chylothorax and Pseudochylothorax

[Lymphatic vessel imaging-Indications and clinical applications]

BACKGROUND

The armamentarium of lymphatic imaging techniques and treatment concepts available at specialized centers has significantly increased in recent years. The rarity and complexity of lymphatic vascular diseases presents the particular challenge of implementing these methods in a meaningful and targeted manner in patient care; however, there are currently no generally accepted diagnostic guidelines.

OBJECTIVE

Which lymphatic imaging technique is useful in which clinical situations?

MATERIAL AND METHODS

This article provides an overview of clinical and technical considerations that are relevant for a targeted evaluation of indications for lymphatic imaging in a multidisciplinary diagnostic and therapeutic approach.

RESULTS

The lymphatic vascular system can be affected by a wide range of primary and secondary pathologies, which often lead to relatively uniform clinical presentations (especially localized swellings, chylolymphatic effusions). In general, dedicated imaging should be discussed if a lymphatic vascular disease is suspected based on such a typical presentation. The choice of imaging strategy is then individually determined by the urgency of treatment, suspected localization and etiology of the pathology, comorbidities, specific properties of the imaging techniques, the treatment strategy pursued and local availability. When interpreting imaging and planning treatment, in addition to the large spectrum of different pathologies, the individual variability of the lymphatic system must also be taken into account.

CONCLUSION

An individual pretherapeutic assessment of lymphatic flow should nowadays be mandatory in order to be able to optimize the therapeutic approach for each patient with a suspected lymphatic vascular disease. Interdisciplinary patient care is of decisive importance.

Evaluation of cytomorphological examination in the diagnosis of pleural effusion

Cytological examination serves as a crucial diagnostic tool for pleural effusion, with its diagnostic efficacy influenced by variations in specimen processing and staining techniques. Cellular morphological analysis of pleural effusions was performed using Wright-Giemsa staining to assess its diagnostic accuracy and clinical utility in differentiating the various etiologies of exudative pleural effusion. A routine examination was conducted on 2305 cases of unexplained pleural effusion, followed by cellular classification and morphological analysis in 1376 cases identified as exudative effusion. Among the 479 patients with malignant tumors, cytomorphological examination identified malignant cells in 295 patients, resulting in a clinical diagnosis coincidence rate of 98.6%. Abnormal cells, including malignant and heterogeneous nuclear cells, were observed in 364 cases, yielding a detection rate of 76.0%. The proportion of positive malignant cells in the newly diagnosed patient group was significantly higher than that in the previously diagnosed group (P < 0.01). Cytological analysis revealed the presence of bacteria, fungi, and phagocytes in 51 out of 1376 cases. The positivity rate for multiple bacterial infections detected through cytology was significantly greater than that identified by culture (P < 0.01). Additionally, various special morphologies and pathogens, which are rare in clinical practice, were detected, including mixed metastasis of small cell lung carcinoma and adenocarcinoma cells, as well as concurrent infections with Talaromyces marneffei and Pneumocystis jirovecii. This method enables the rapid and comprehensive differentiation between malignant tumors, tuberculosis, pneumonia, and rare exudative pleural effusions resulting from specific clinical conditions.

Chylothorax as an unusual manifestation of transthyretin cardiac amyloidosis: a case report

Background

Amyloidosis is a multi-organ disease of emerging significance in the field of cardiology. Chylothorax, a specific form of pleural effusion characterized by lymphatic fluid accumulation in the pleural cavity, is an extremely rare manifestation of amyloidosis. Notably, only five cases of chylothorax related to cardiac amyloidosis have been reported worldwide, all in amyloid light chain (AL) amyloidosis. No cases have been documented in amyloid transthyretin (ATTR) amyloidosis. Furthermore, elevated levels of serum carbohydrate antigen (CA) 125 have been associated with a poor prognosis in patients with AL cardiac amyloidosis.

Case summary

We report the case of an 85-year-old Austrian man with pronounced left ventricular hypertrophy, monoclonal gammopathy, and a history of atrial fibrillation. Further examinations, including myocardial biopsy, confirmed the diagnosis of ATTR cardiac amyloidosis. A significant right-sided pleural effusion was also observed. Thoracocentesis diagnosed chylothorax, confirmed by lymphangiography. Elevated CA 125 levels were found in both serum and pleural fluid, with no other findings suspicious for malignancy. The patient underwent a short break in oral anticoagulation and received prophylactic low-molecular-weight heparin for myocardial biopsy, thoracocentesis, and lymphangiography. However, they died a few days later due to an embolic stroke.

Discussion

At this time, we can only speculate about the pathomechanism of chylothorax development in the context of amyloidosis. We recommend further investigation of similar cases to deepen understanding of the underlying causes and identify potential treatment strategies. Additionally, the utility of CA 125 as a prognostic marker in ATTR amyloidosis needs further investigation.

Refractory chylothorax following COVID-19: Successful surgical management of a rare complication; a case report

INTRODUCTION AND IMPORTANCE

Chylothorax is an uncommon complication linked to COVID-19. The fundamental pathophysiology and most effective management strategy are still uncertain.

CASE PRESENTATION

A 72-year-old man presented with worsening dyspnea and fatigue one month post-COVID-19. Imaging demonstrated a significant right pleural effusion, with thoracentesis confirming the presence of chylothorax. Despite the implementation of conservative interventions, the effusion remained unresolved. During the right thoracotomy procedure, a 1 cm (about 0.39 in) perforation in proximity to the Azygos vein, encircled by hypertrophic lymph nodes, was identified. Surgical intervention successfully alleviated the symptoms.

CLINICAL DISCUSSION

This case implies that mediastinal lymphadenopathy because of COVID-19 could potentially obstruct and interfere with the thoracic duct. This emphasizes the significance of considering chylothorax as a crucial diagnostic possibility in individuals presenting with new onset pleural effusions following COVID-19. Although conservative approaches are typically the first line of management, persistent cases may necessitate surgical intervention to target the root cause.

CONCLUSIONS

Additional research is imperative to elucidate the intricate pathways connecting COVID-19 and chylothorax, as well as to ascertain the most effective diagnostic and therapeutic approaches.

Refractory massive chylothorax following robot-assisted laparoscopic splenectomy with pericardial devascularization treated with trans-jugular intrahepatic portosystemic shunt: a case report

The development of a chylothorax after robot-assisted laparoscopic splenectomy combined with pericardial devascularization (LSPD) is rare. The robot-assisted procedure is similar to the standard LSPD, but surgeons must remain vigilant about potential chylothorax caused by recurrence of portal hypertension in patients with cirrhosis, an event that leads to variceal bleeding in the gastric fundus or a massive chylothorax caused by a thoracic duct fistula. We report a rare case of massive chylothorax after robot-assisted LSPD and review the literature to help elucidate the mechanisms of portal hypertension after LSPD, reduce surgical complications, and improve long-term patient outcomes. After LSPD, portal pressure monitoring, coagulation function testing, and portal vein CT imaging help in excluding portal vein thromboses and ensuring appropriate anticoagulation to reduce the development of thoracic duct fistulas. If portal hypertension recurs after surgery and a high-output chylothorax develops, conservative treatment becomes ineffective. Treatment with an active trans-jugular intrahepatic portosystemic shunt (TIPS) is recommended to lower the portal pressure.

Clinical overview of the physiology and pathophysiology of pleural fluid movement: a narrative review

In physiological conditions, the pleural space couples the lung with the chest wall and contains a small amount of fluid in continuous turnover. The volume of pleural fluid is the result from the balance between the entry of fluid through the pleural capillaries and drainage by the lymphatics in the most dependent areas of the parietal pleura. Fluid filtration is governed by Starling forces, determined by the hydrostatic and oncotic pressures of the capillaries and the pleural space. The reabsorption rate is 28 times greater than the rate of pleural fluid production. The mesothelial layer of the inner lining of the pleural space is metabolically active and also plays a role in the production and reabsorption of pleural fluid. Pleural effusion occurs when the balance between the amount of fluid that enters the pleural space and the amount that is reabsorbed is disrupted. Alterations in hydrostatic or oncotic pressure produce a transudate, but they do not cause any structural damage to the pleura. In contrast, disturbances in fluid flow (increased filtration or decreased reabsorption) produce an exudate via several mechanisms that cause damage to pleural layers. Thus, cellular processes and the inflammatory and immune reactions they induce determine the composition of pleural fluid. Understanding the underlying pathophysiological processes of pleural effusion, especially cellular processes, can be useful in establishing its aetiology.

Pediatric Chylothorax Treated With Lymphangiography and Thoracic Duct Embolization: A Case Report

A chylothorax, the accumulation of lymphatic fluid in the pleural space, may occur for a variety of reasons. It is commonly seen in adults post-thoracic surgery. We present the case of a seven-month-old girl with a right-sided chylothorax in the setting of non-accidental trauma. Treatment options for a chylothorax include surgical ligation of the thoracic duct or, as in this case, a minimally invasive procedure performed by interventional radiology known as lymphangiography with thoracic duct embolization. This case highlights interventional radiologists' ability to treat complex lymphatic pathologies effectively with minimally invasive techniques.

Traumatic chylothorax in urbanized free-ranging black-tufted marmosets (Callithrix penicillata)

After fatal traumatic injuries, three urbanized free-ranging marmosets developed a milky white or pink-white thoracic alkaline effusion with high specific gravity, triglyceride levels, and predominance of small lymphocytes. Chylothorax is an uncommon thoracic fluid accumulation in animals and humans and has not been reported in free-ranging non-human primates.

Utility of 99mTc-Sulfur Colloid Lymphoscintigraphy and SPECT/CT in Chylothorax and Chylous Ascites

Purpose

To assess the diagnostic efficacy of 99mTc-sulfur colloid lymphoscintigraphy in chylothorax and chylous ascites, and the utility of single-photon emission computed tomography-computed tomography (SPECT/CT) in localizing the sites of leaks.

Methods

Data from patients who underwent lymphoscintigraphy for clinical suspicion of chylothorax or chylous ascites were retrospectively analyzed. Biochemical fluid analysis was taken as the reference standard. Pleural fluid triglyceride level > 110 mg/dL (with pleural fluid/serum ratio > 1) and a cholesterol level < 200 mg/dL (with pleural fluid/serum ratio < 1) were considered confirmatory for chylothorax. Ascitic fluid triglyceride level > 200 mg/dL with a low cholesterol level (ascites fluid/serum ratio < 1) was considered confirmatory for chylous ascites.

Results

26 patients (15 males, 57.7%) aged 9 months to 68 years were enrolled in the study. Based on the reference standard, 17 had chylothorax or chylous ascites (9 with surgical history). Lymphoscintigraphy was positive in 16 (with 1 false positive) and negative in 10 (with 2 false negatives). The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of lymphoscintigraphy were 88.2% (63.6-98.5%), 88.9% (51.8-99.7%), 80.0% (51.6-93.8%), 93.8% (70.1-99.0%), and 88.5% (69.9-97.6%), respectively. SPECT/CT could localize sites of leaks in 61.5% (8/13) with a localization rate of 77.8% (7/9) and 25.0% (1/4) in patients with surgical and nonsurgical causes, respectively.

Conclusion

99mTc-sulfur colloid lymphoscintigraphy is a highly efficacious noninvasive modality to diagnose chylothorax or chylous ascites with a high positive predictive value. SPECT/CT could localize the sites of leaks more frequently in patients with surgical causes.

Lymphoscintigraphy findings in patients with chylothorax: influence of biochemical parameters

BACKGROUND

Chylothorax is a condition that can be challenging to diagnose due to its nonspecific clinical presentation. Several biochemical parameters of chylous pleural effusion have been identified as important indicators for the diagnosis of chylothorax. Lymphoscintigraphy is utilized to assess chylothorax and determine the location of chyle leakage. The present study aimed to evaluate the correlation between the biochemical parameters of chylous pleural effusion and 99mTc-dextran (99mTc-DX) lymphoscintigraphy in diagnosing chylothorax.

MATERIAL AND METHODS

A total of 120 patients were enrolled in the study, 83 of the patients with unilateral chylothorax, and 37 with bilateral chylothorax. All patients underwent both 99mTc-DX lymphoscintigraphy and pleural effusion laboratory analysis. The 99mTc-DX lymphoscintigraphy images were categorized as positive or negative groups based on the presence or absence of abnormal radioactive tracer accumulation in the thorax, respectively. The biochemical parameters of the two groups were subsequently compared.

RESULTS

Among these patients, 101 (84.17%) had exudative effusions, while 19 (15.83%) had transudative effusions, as determined by the levels of pleural effusion protein, lactate dehydrogenase and cholesterol. Abnormal tracer accumulation in thorax was observed in 82 patients (68.33%). Our findings indicated that lymphoscintigraphy results were not associated with exudative and transudative chylothorax (P = 0.597). The lymphoscintigraphy positive group displayed significantly higher levels of pleural effusion triglyceride and pleural effusion triglyceride/serum triglyceride ratio in all biochemical parameters, compared to the negative group (P = 0.000 and P = 0.005). We identified cutoff values of 2.870 mmol/L for pleural effusion triglycerides and 4.625 for pleural effusion triglyceride/serum triglyceride ratio, respectively, which can facilitate differentiating the positive and negative cases on lymphoscintigraphy.

CONCLUSION

Lymphoscintigraphy technique is a dependable diagnostic tool for the qualitative assessment of chylous pleural effusion. Higher pleural effusion triglyceride level and pleural effusion triglyceride/serum triglyceride ratio indicate a positive result in patients with chylothorax on lymphoscintigraphy, with the cutoff values of 2.870 mmol/L and 4.625 aiding in the diagnosis.

Back to the Future II-A Comprehensive Update on the Rapidly Evolving Field of Lymphatic Imaging and Interventions

ABSTRACT

Lymphatic imaging and interventional therapies of disorders affecting the lymphatic vascular system have evolved rapidly in recent years. Although x-ray lymphangiography had been all but replaced by the advent of cross-sectional imaging and the scientific focus shifted to lymph node imaging (eg, for detection of metastatic disease), interest in lymph vessel imaging was rekindled by the introduction of lymphatic interventional treatments in the late 1990s. Although x-ray lymphangiography is still the mainstay imaging technique to guide interventional procedures, several other, often less invasive, techniques have been developed more recently to evaluate the lymphatic vascular system and associated pathologies. Especially the introduction of magnetic resonance, and even more recently computed tomography, lymphangiography with water-soluble iodinated contrast agent has furthered our understanding of complex pathophysiological backgrounds of lymphatic diseases. This has led to an improvement of treatment approaches, especially of nontraumatic disorders caused by lymphatic flow abnormalities including plastic bronchitis, protein-losing enteropathy, and nontraumatic chylolymphatic leakages. The therapeutic armamentarium has also constantly grown and diversified in recent years with the introduction of more complex catheter-based and interstitial embolization techniques, lymph vessel stenting, lymphovenous anastomoses, as well as (targeted) medical treatment options. The aim of this article is to review the relevant spectrum of lymphatic disorders with currently available radiological imaging and interventional techniques, as well as the application of these methods in specific, individual clinical situations.

Chylothorax and chylous ascites due to juvenile paracoccidioidomycosis: a case report

Paracoccidioidomycosis (PCM) is a systemic fungal infection caused by Paracoccidioides species. Chylothorax is a rare complication of PCM. A 16-year-old adolescent presented daily fever, lymphadenomegaly, sweating, weight loss, ventilatory-dependent pain, and dysphagia, which confirmed PCM. During treatment, the patient developed chylothorax and chylous ascites. Chronic inflammatory and fibrotic lymphadenopathy may obstruct lymphatic vessels, resulting in the extravasation of lymph into the abdomen or pleural cavities. Chylothorax is one of several complications of PCM and can lead to respiratory insufficiency, even in patients undergoing antifungal therapy.

Interventional Management of Acquired Lymphatic Disorders

The lymphatic system is a complex network of tissues, vessels, and channels found throughout the body that assists in fluid balance and immunologic function. When the lymphatic system is disrupted related to idiopathic, iatrogenic, or traumatic disorders, lymphatic leaks can result in substantial morbidity and/or mortality. The diagnosis and management of these leaks is challenging. Modern advances in lymphatic imaging and interventional techniques have made radiology critical in the multidisciplinary management of these disorders. The authors provide a review of conventional and clinically relevant variant lymphatic anatomy and recent advances in diagnostic techniques such as MR lymphangiography. A detailed summary of technical factors related to percutaneous lymphangiography and lymphatic intervention is presented, including transpedal and transnodal lymphangiography. Traditional transabdominal access and retrograde access to the central lymph nodes and thoracic duct embolization techniques are outlined. Newer techniques including transhepatic lymphangiography and thoracic duct stent placement are also detailed. For both diagnostic and interventional radiologists, an understanding of lymphatic anatomy and modern diagnostic and interventional techniques is vital to the appropriate treatment of patients with acquired lymphatic disorders. ^©RSNA, 2022.

Lymphatic Interventions in the Cancer Patient

PURPOSE OF REVIEW

The incidence of lymphatic leakage (iatrogenic and non-iatrogenic) is growing in cancer population due to the increased complexity of the surgical procedures and improved overall survival in cancer patients. The purpose of this article is to review the contemporary approach in the field of percutaneous lymphatic embolization in cancer patients with lymphatic leaks.

RECENT FINDINGS

Since the advent of intranodal lymphangiography in 2011 alongside with the MR and CT lymphangiography, the accuracy of diagnosis of the lymphatic diseases has significantly improved significantly. These advancements have triggered a revival of minimally invasive lymphatic interventions. Lymphatic embolization is expanding from the classic indication, thoracic duct embolization, to other lymphatic disorders (chylous ascites, lymphoceles, liver lymphorrhea, protein-losing enteropathy). The growth of lymphatic research and the standardization of the lymphatic interventions require a multidisciplinary and collaborative approach between physicians and researchers.

Pulmonary Kaposi Sarcoma without Respiratory Symptoms and Skin Lesions in an HIV-Naïve Patient: A Case Report and Literature Review

Kaposi sarcoma (KS) is a multifocal lympho-angioproliferative, mesenchymal low-grade tumor associated with a γ2-herpesvirus, named Kaposi sarcoma-associated virus or human herpesvirus (KSHV/HHV8). The lung is considered a usual anatomical location of KS, despite being infrequent, often in association with extensive mucocutaneous lesions and very uncommonly as an isolated event. We report a case of a pulmonary KS (pKS) in a human immunodeficiency virus (HIV) naïve patient, which was atypical due to a lack of cutaneous involvement and an absence of respiratory symptoms. The pKS was initially identified as a tumoral suspected nodular lesion and only after immunohistochemical analysis was it characterized as KS. Furthermore, the diagnosis of pKS led to the discovery of the HIV-seropositive status of the patient, previously unknown. Our report underlines the importance of considering pKS even without skin lesions and as a first manifestation of HIV infection. We also reviewed literature on the current knowledge about pKS in people living with HIV (PLWH) to underline how one of the most common HIV/acquired immunodeficiency syndrome (AIDS) associated tumors can have a challenging localization and be difficult to recognize.