MedGen

Immunodeficiency-69 (IMD69) is an autosomal recessive disorder characterized by increased susceptibility to disseminated mycobacterial infection, including after BCG (bacille Calmette-Guerin) vaccination. Affected individuals develop fever, hepatosplenomegaly, leukocytosis, and thrombocytosis during the acute infection. There appears to be normal immunologic function against other pathogens, including viruses and bacteria. Immunologic work-up shows normal parameters, but patient T and NK cells fail to produce gamma-interferon (IFNG) when stimulated in vitro (summary by Kerner et al., 2020). IMD69 is a form of mendelian susceptibility to mycobacterial disease (MSMD) (see, e.g., IMD27A; 209950). [from OMIM]

Tuberous sclerosis complex (TSC) involves abnormalities of the skin (hypomelanotic macules, confetti skin lesions, facial angiofibromas, shagreen patches, fibrous cephalic plaques, ungual fibromas); brain (subependymal nodules, cortical tubers, and subependymal giant cell astrocytomas [SEGAs], seizures, intellectual disability / developmental delay, psychiatric illness); kidney (angiomyolipomas, cysts, renal cell carcinomas); heart (rhabdomyomas, arrhythmias); and lungs (lymphangioleiomyomatosis [LAM], multifocal micronodular pneumonocyte hyperplasia). Central nervous system tumors are the leading cause of morbidity and mortality; renal disease is the second leading cause of early death. [from GeneReviews]

The pathogenesis of HIV infection and the progression from infection to AIDS vary significantly between exposed individuals. Infection occurs after the virus, which has macrophage (M)- and T lymphocyte (T)-tropic strains and more than 12 subtypes, survives an array of nonspecific, nongenetic environmental and host factors. [from OMIM]

HCV, which is principally transmitted by blood, infects about 3% of the world's population. HCV infection causes acute hepatitis, which is self-resolving in 20 to 50% of cases but does not confer permanent immunity. In 50 to 80% of cases, HCV infection becomes chronic and results in chronic hepatitis, cirrhosis, and hepatocellular carcinoma. As a result, HCV infection is a leading killer worldwide and the most common cause of liver failure in the U.S. HCV is opportunistic in individuals infected with human immunodeficiency virus (HIV; see 609423), approximately 25% of whom are coinfected with HCV. HCV infection is also associated with cryoglobulinemia (see 123550), a B-lymphocyte proliferative disorder (Pawlotsky, 2004; Chisari (2005); Pileri et al., 1998). [from OMIM]

Mycobacterium tuberculosis latently infects approximately one-third of humanity and is comparable only to human immunodeficiency virus (HIV; see 609423) as a leading infectious cause of mortality worldwide. Obstacles for controlling TB infection include lengthy treatment regimens of 6 to 9 months, drug resistance, lack of a highly efficacious vaccine, and incomplete understanding of the factors that control infectivity and disease progression. Although only 10% of individuals infected with M. tuberculosis develop active disease, the immune responses associated with TB susceptibility or resistance are not known. In addition, it is not known why some individuals have disseminated TB that spreads to the meninges and central nervous system, while most people have localized disease in the lungs. A number of studies suggest that host genetic factors influence susceptibility and resistance to TB (review by Berrington and Hawn, 2007). [from OMIM]

Aplastic anemia is a serious disorder of the bone marrow that affects between 2 and 5 persons per million per year. About 75% of these cases are classified as idiopathic (Young, 2000). In about 15% of cases a drug or infection can be identified that precipitates the aplasia, although why only some individuals are susceptible is unclear. In about 5 to 10% of patients, the aplastic anemia is constitutional--i.e., is familial or presents with one or more associated somatic abnormalities (summary by Vulliamy et al., 2002). [from OMIM]