MedGen

Hemophagocytic syndrome (HPS) is a rare immune disease (see this term) and a potentially life-threatening disorder characterized by cytokine storm and overwhelming inflammation causing fever, hepatosplenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia, and hemophagocytosis in bone marrow, liver, spleen or lymph nodes. It can be either primary due to a genetic defect (primary hemophagocytic lymphohistiocytosis ; see this term), or secondary to malignancies, to infections, most commonly with viruses such as Epstein-Barr virus or cytomegalovirus, human immunodeficiency virus, or to autoimmune disorders such as systemic lupus erythematosus or adult-onset Still disease (secondary hemophagocytic lymphohistiocytosis) (see these termes). [from ORDO]

Familial hemophagocytic lymphohistiocytosis (fHLH), defined as the presence of biallelic pathogenic variants in one of four genes (PRF1, STX11, STXBP2, or UNC13D), is an immune deficiency characterized by the overactivation and excessive proliferation of T lymphocytes and macrophages, leading to infiltration and damage of organs including the bone marrow, liver, spleen, and brain. Familial HLH usually presents as an acute illness with prolonged and high fever, cytopenias, and hepatosplenomegaly. Rash and lymphadenopathy are less common. Individuals with fHLH may also exhibit liver dysfunction and neurologic abnormalities. Although manifestations of fHLH are usually evident within the first months or years of life and may develop in utero, symptomatic presentation can occur throughout childhood and into adulthood. Median survival in untreated infants with fHLH who develop active disease is less than two months after onset of manifestations; progressive manifestations of fHLH, organ dysfunction, invasive infection, and bleeding account for the majority of deaths. Use of etoposide-containing regimens such as the HLH-94 and HLH-2004 protocols followed by allogeneic hematopoietic stem cell transplantation (HSCT) has improved survival. [from GeneReviews]

A rare spondyloarthritis characterized by acute or chronic sterile synovitis with or without extra-articular manifestations, becoming manifest after an infection. [from ORDO]

A group of inflammatory rheumatic diseases associated with arthritis and enthesitis, and often involving the axial skeleton. The most common form of spondyloarthritis is ankylosing spondylitis. Other forms include axial spondyloarthritis, peripheral spondyloarthritis, reactive arthritis, psoriatic arthritis/spondylitis and enteropathic arthritis/spondylitis. [from MONDO]

Inflammation of the vertebrae (vertebral bodies) or spine. [from HPO]

The inflammation of one or more joints caused by any infectious pathogen within the joint space. Symptoms include pain, stiffness, and decreased range of motion in the affected joint. [from NCI]

A disease involving the vertebral column. [from MONDO]

A group of disorders including ankylosing spondylitis, axial spondylarthritis, spondyloarthritis due to inflammatory bowel disease, and other conditions. They share the common features of inflammation of axial joints, asymmetric oligoarthritis, dactylitis, and enthesitis. [from SNOMEDCT_US]

The inflammation of one or more joints caused by a bacterial infection within the joint space. Symptoms include pain, stiffness, and decreased range of motion in the affected joint. [from NCI]

A disorder that follows infection but is distinct from the infection itself and its usual manifestations [from SNOMEDCT_US]