Central Conducting Lymphatic Anomaly (CCLA)

Overview

Central conducting lymphatic anomaly (CCLA) is one of a spectrum of complex lymphatic anomalies with multiple overlapping symptoms. Enlargement of lymphatic channels (lymphangiectasia), dysmotility, or distal obstruction results in inadequate clearing of lymph with resultant stasis and reflux.

Symptoms and History

The lymphatic system is part of our immune system. Normally the lymphatic system develops as a series of nodes and channels which drain from the periphery into central channels, named the cisterna chyli and the thoracic duct.

When there is obstruction or anomalous formation of the lymphatic system, this can result in leakage of lymph fluid into various compartments: skin and interstitium (lymphedema), pleural cavity (chylothorax), peritoneal cavity (chylous ascites) and even into bone. If there is involvement of skin, can result in cutaneous vesicles which weep and ooze.

Central conducting lymphatic anomalies (CCLA) are poorly described in the literature. Broadly, any dysfunction/disorder of the central channels responsible for lymphatic drainage can be categorized into the CCLA spectrum.

Diagnosis

Clinical Exam. Depending on the region involved, patients can present with various symptoms. Patients may present with chylothorax, chylous ascites, protein losing enteropathy, extremity swelling, cutaneous lymphatic vesicles, etc.

Imaging. On MRI (Magnetic Resonance Imaging), CCLA may demonstrate diffuse abnormal signal within the mesentery as well as abnormal signal in the para-aortic lymphatic chain. Patients may also demonstrate ascites or pleural effusion.

MRL (Magnetic Resonance Lymphangiography) or Intranodal Lymphangiography can also be performed for a more dynamic exam regarding peripheral to central drainage pattern of lymphatics and identify if a leak is present.

Laboratory. While certain laboratory findings can support a diagnosis, because of overlap of complex lymphatic anomalies findings may be non-specific. Complex lymphatic disorders in general have been known to shown an elevated D-dimer as well as mild thrombocytopenia (low platelet count). Laboratory studies on pleural effusion or abdominal ascites may demonstrate elevated levels of triglycerides, consistent with chyle.

Genetics. Not much is yet known regarding genetics of CCLA.

Treatment

The treatment of CCLA and other complex lymphatic anomalies depends on the manifestation in which the patient presents. Currently, most treatments are considered palliative.

  • Pleurodesis can be performed for recurrent pleural effusion for symptomatic relief/control
  • Thoracentesis/paracentesis/drainage catheter placement/Denver shunt can also be performed for symptom control (when no other interventions have been successful)
  • Sclerotherapy/CO2 photovaporization can help with cutaneous vesicles which ooze and weep.
  • In specific situations, thoracic duct- external jugular vein anastomosis may help improve lymphatic drainage.
  • If lymphatic leak is identified, cisterna chyli or thoracic duct embolization could be performed by Interventional Radiology
  • Medical/supportive management in pulmonary disease, such as improving pulmonary clearance with chest physiotherapy or various medications
  • Sirolimus is currently being studied in a host of vascular anomalies/malformations and has been shown to improve symptoms/control of disease in specific situations