MedGen

Autoimmune lymphoproliferative syndrome type III is an autosomal recessive disorder of immune dysregulation. The phenotype is variable, but most patients have significant lymphadenopathy associated with variable autoimmune manifestations. Some patients may have recurrent infections. Lymphocyte accumulation results from a combination of impaired apoptosis and excessive proliferation (summary by Oliveira, 2013). For a general description and a discussion of genetic heterogeneity of ALPS, see 601859. [from OMIM]

Blockage of blood flow through the superior vena cava (SVC). Because the venous drainage from the upper extremities, upper thorax and head is obstructed, SVC obstruction presents with symptoms related to engorgement of these areas. Both the degree of SVC compromise and the extent of collateral veins determine the varied clinical presentation, which can be as mild as slight facial and upper extremity edema or as dire as intracranial swelling, seizures, hemodynamic instability and tracheal obstruction. [from HPO]