Chylothorax in a patient with metastatic Kaposi sarcoma: Differential diagnostic considerations

Nontraumatic Chylothorax: Nonenhanced MR Lymphography

Chylothorax is a rare cause of pleural effusion, secondary to accumulation of lymph in the pleural space. Diagnosis is based on the triglyceride and cholesterol content of pleural fluid obtained with thoracentesis. Because the lymphatic system plays an essential role in fat absorption and immune response, lymphatic leak associated with chylothorax may cause life-threatening malnutrition and immunodeficiency. Chylothorax is usually described as traumatic or nontraumatic. The main cause of chylothorax is traumatic, typically postsurgical, secondary to iatrogenic direct puncture of the thoracic duct during thoracic surgery. Causes of nontraumatic chylothorax include a wide range of differential diagnoses. Lymphoma and thoracic malignancies are the most common causes and are responsible for chylothorax by extrinsic compression or invasion of the thoracic duct. Other rare causes include primary and secondary diffuse lymphatic diseases, responsible for chylothorax by lymphatic vessel wall dysfunction. Imaging the lymphatic system remains a challenge in the days of modern imaging. Nonenhanced MR lymphography is a noninvasive technique based on heavily T2-weighted sequences, thus enabling visualization of the lymphatic circulation. This technique allows diagnosis and differential diagnosis, evaluation of disease severity, and guidance of therapeutic management in nontraumatic chylothorax. Furthermore, it may offer radiologic classification of primary lymphatic diseases on the basis of morphologic features of lymphatic vessels. The authors describe the anatomy and physiology of the thoracic lymphatic system, present the technique of nonenhanced MR lymphography, and discuss pathophysiologic mechanisms and imaging features in different causes of nontraumatic chylothorax. ^©RSNA, 2020.

Intractable pleural effusion in Kaposi sarcoma following antiretroviral therapy in a Caucasian female infected with HIV

We report the case of a 57-year-old Caucasian woman with AIDS-related disseminated Kaposi sarcoma (KS) characterised by the combination of several unusual features. The chylous nature of the pleural effusions, the documented parietal pleural involvement at thoracoscopy and the marked clinical worsening through an immune reconstitution syndrome following antiretroviral therapy initiation represent several rare situations that occurred in the same female patient. In addition, the use of indwelling pleural catheters for dyspnoea palliation also represents a rare therapeutic intervention. This case is a reminder of the possibility of AIDS-related pleural KS, now uncommon in the era of antiretroviral therapy.

Chylous ascites in disseminated Kaposi sarcoma: an unusual manifestation as immune reconstitution inflammatory syndrome

A 29-year-old man with diarrhoea, fever, abdominal pain and multiple purple papular lesions, neither pruriginous nor painful, was diagnosed with HIV-1 infection and disseminated Kaposi sarcoma (KS) with gastrointestinal involvement. He was started on highly active antiretroviral therapy immediately, as well as doxorubicin. Three weeks later, the patient developed bilateral moderate pleural effusion and large-volume ascites compatible with chylothorax and chylous ascites. An immune reconstitution inflammatory syndrome (IRIS) reaction was assumed. KS flare was associated with lymphatic obstruction and infiltration of thoracic duct by the tumour itself with leakage of chylous into pleural and peritoneal cavities. KS is the most common tumour in HIV patients and the existence of related effusions is not uncommon. KS-related chylothorax is an unusual manifestation of KS; there are only four cases described in the literature of chylous ascites related to KS-HIV. Overall survival is improving in KS but explosive and debilitating IRIS reactions can explain cases with poor prognosis.

Chylothorax in a patient with HIV-related Kaposi's sarcoma

We present a case of a 33-year-old man with a background of HIV and Kaposi's sarcoma (KS), who presented with a right sided chylothorax. He was managed with percutaneous chest drainage and talc pleurodesis, in addition to his chemotherapy and antiretroviral therapy for KS and HIV, respectively. Good clinical control of the chylothorax remained 4 months post drainage. This case report summarises the approach to investigating and managing pleural effusion, and in particular chylothorax, in HIV patients.

Differences in survival among adults with HIV-associated Kaposi's sarcoma during routine HIV treatment initiation in Zomba district, Malawi: a retrospective cohort analysis

Background

The HIV epidemic is a major public health concern throughout Africa. Malawi is one of the worst affected countries in sub-Saharan Africa with a 2014 national HIV prevalence currently estimated at 10% (9.3-10.8%) by UNAIDS. Study reports, largely in the African setting comparing outcomes in HIV patients with and without Kaposi's sarcoma (KS) indicate poor prognosis and poor health outcomes amongst HIV+KS patients. Understanding the mortality risk in this patient group could help improve patient management and care.

Methods

Using data for the 559 adult HIV+KS patients who started ART between 2004 and September 2011 at Zomba clinic in Malawi, we estimated relative hazard ratios for all-cause mortality by controlling for age, sex, TB status, occupation, date of starting treatment and distance to the HIV+KS clinic.

Results

Patients with tuberculosis (95% CI: 1.05-4.65) and patients who started ART before 2008 (95% CI: 0.34-0.81) were at significantly greater risk of dying. A random-effects Cox model with Log-Gaussian frailties adequately described the variation in the hazard for mortality.

Conclusion

The year of starting ART and TB status significantly affected survival among HIV+KS patients. A sub-population analysis of this kind can inform an efficient triage system for managing vulnerable patients.