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1.

Ehlers-Danlos syndrome, periodontal type, 2

Ehlers-Danlos syndrome is a group of disorders that affect the connective tissues that support the skin, bones, blood vessels, and many other organs and tissues. Defects in connective tissues cause the signs and symptoms of Ehlers-Danlos syndrome, which vary from mildly loose joints to life-threatening complications.Previously, there were more than 10 recognized types of Ehlers-Danlos syndrome, differentiated by Roman numerals. In 1997, researchers proposed a simpler classification that reduced the number of major types to six and gave them descriptive names: the classical type (formerly types I and II), the hypermobility type (formerly type III), the vascular type (formerly type IV), the kyphoscoliosis type (formerly type VIA), the arthrochalasia type (formerly types VIIA and VIIB), and the dermatosparaxis type (formerly type VIIC). This six-type classification, known as the Villefranche nomenclature, is still commonly used. The types are distinguished by their signs and symptoms, their underlying genetic causes, and their patterns of inheritance. Since 1997, several additional forms of the condition have been described. These additional forms appear to be rare, affecting a small number of families, and most have not been well characterized.Although all types of Ehlers-Danlos syndrome affect the joints and skin, additional features vary by type. An unusually large range of joint movement (hypermobility) occurs with most forms of Ehlers-Danlos syndrome, particularly the hypermobility type. Infants with hypermobile joints often have weak muscle tone, which can delay the development of motor skills such as sitting, standing, and walking. The loose joints are unstable and prone to dislocation and chronic pain. Hypermobility and dislocations of both hips at birth are characteristic features in infants with the arthrochalasia type of Ehlers-Danlos syndrome.Many people with Ehlers-Danlos syndrome have soft, velvety skin that is highly stretchy (elastic) and fragile. Affected individuals tend to bruise easily, and some types of the condition also cause abnormal scarring. People with the classical form of Ehlers-Danlos syndrome experience wounds that split open with little bleeding and leave scars that widen over time to create characteristic "cigarette paper" scars. The dermatosparaxis type of the disorder is characterized by skin that sags and wrinkles. Extra (redundant) folds of skin may be present as affected children get older.Some forms of Ehlers-Danlos syndrome, notably the vascular type and to a lesser extent the kyphoscoliosis and classical types, can involve serious and potentially life-threatening complications due to unpredictable tearing (rupture) of blood vessels. This rupture can cause internal bleeding, stroke, and shock. The vascular type of Ehlers-Danlos syndrome is also associated with an increased risk of organ rupture, including tearing of the intestine and rupture of the uterus (womb) during pregnancy. People with the kyphoscoliosis form of Ehlers-Danlos syndrome experience severe, progressive curvature of the spine that can interfere with breathing. [from GTR]

MedGen UID:
934648
Concept ID:
C4310681
Disease or Syndrome
2.

Macular degeneration, age-related, 15

Age-related macular degeneration is an eye disease that is a leading cause of vision loss in older people in developed countries. The vision loss usually becomes noticeable in a person's sixties or seventies and tends to worsen over time.Age-related macular degeneration mainly affects central vision, which is needed for detailed tasks such as reading, driving, and recognizing faces. The vision loss in this condition results from a gradual deterioration of light-sensing cells in the tissue at the back of the eye that detects light and color (the retina). Specifically, age-related macular degeneration affects a small area near the center of the retina, called the macula, which is responsible for central vision. Side (peripheral) vision and night vision are generally not affected, but reduced dim light (scotopic) vision often occurs in the early stages of the disease.Researchers have described two major types of age-related macular degeneration, known as the dry form and the wet form. The dry form is much more common, accounting for 85 to 90 percent of all cases of age-related macular degeneration. It is characterized by a buildup of yellowish deposits called drusen beneath the retina and vision loss that worsens slowly over time. The condition typically affects vision in both eyes, although vision loss often occurs in one eye before the other.The wet form of age-related macular degeneration is associated with severe vision loss that can worsen rapidly. This form of the condition is characterized by the growth of abnormal, fragile blood vessels underneath the macula. These vessels leak blood and fluid, which damages the macula and makes central vision appear blurry and distorted. [from GTR]

MedGen UID:
816372
Concept ID:
C3810042
Disease or Syndrome
3.

Complement factor B deficiency

MedGen UID:
816280
Concept ID:
C3809950
Disease or Syndrome
4.

Age-related macular degeneration 14

Age-related macular degeneration is an eye disease that is a leading cause of vision loss in older people in developed countries. The vision loss usually becomes noticeable in a person's sixties or seventies and tends to worsen over time.Age-related macular degeneration mainly affects central vision, which is needed for detailed tasks such as reading, driving, and recognizing faces. The vision loss in this condition results from a gradual deterioration of light-sensing cells in the tissue at the back of the eye that detects light and color (the retina). Specifically, age-related macular degeneration affects a small area near the center of the retina, called the macula, which is responsible for central vision. Side (peripheral) vision and night vision are generally not affected, but reduced dim light (scotopic) vision often occurs in the early stages of the disease.Researchers have described two major types of age-related macular degeneration, known as the dry form and the wet form. The dry form is much more common, accounting for 85 to 90 percent of all cases of age-related macular degeneration. It is characterized by a buildup of yellowish deposits called drusen beneath the retina and vision loss that worsens slowly over time. The condition typically affects vision in both eyes, although vision loss often occurs in one eye before the other.The wet form of age-related macular degeneration is associated with severe vision loss that can worsen rapidly. This form of the condition is characterized by the growth of abnormal, fragile blood vessels underneath the macula. These vessels leak blood and fluid, which damages the macula and makes central vision appear blurry and distorted. [from GTR]

MedGen UID:
815983
Concept ID:
C3809653
Disease or Syndrome
5.

Age-related macular degeneration 13

Age-related macular degeneration (ARMD) is a multifactorial disorder of the central retina that is the most prevalent cause of progressive vision loss in the developed world. As in other chronic age-related diseases, most cases result from interplay between multiple environmental and genetic factors, with a resultant spectrum of phenotypes. In rare cases, ARMD may manifest early, but there is an exponential rise in prevalence after the age of 60 years (summary by Pras et al., 2015). For a phenotypic description and a discussion of genetic heterogeneity of age-related macular degeneration (ARMD), see 603075. [from GTR]

MedGen UID:
815853
Concept ID:
C3809523
Disease or Syndrome
6.

Common variable immunodeficiency 7

Common variable immune deficiency (CVID) is a disorder that impairs the immune system. People with CVID are highly susceptible to infection from foreign invaders such as bacteria, or more rarely, viruses and often develop recurrent infections, particularly in the lungs, sinuses, and ears. Pneumonia is common in people with CVID. Over time, recurrent infections can lead to chronic lung disease. Affected individuals may also experience infection or inflammation of the gastrointestinal tract, which can cause diarrhea and weight loss. Abnormal accumulation of immune cells causes enlarged lymph nodes (lymphadenopathy) or an enlarged spleen (splenomegaly) in some people with CVID. Immune cells can accumulate in other organs, forming small lumps called granulomas.Approximately 25 percent of people with CVID have an autoimmune disorder, which occurs when the immune system malfunctions and attacks the body's tissues and organs. The blood cells are most frequently affected by autoimmune attacks in CVID; the most commonly occurring autoimmune disorders are immune thrombocytopenia purpura, which is an abnormal bleeding disorder caused by a decrease in cell fragments involved in blood clotting called platelets, and autoimmune hemolytic anemia, which results in premature destruction of red blood cells. Other autoimmune disorders such as rheumatoid arthritis can occur. Individuals with CVID also have a greater than normal risk of developing certain types of cancer, including a cancer of immune system cells called non-Hodgkin lymphoma and less frequently, stomach (gastric) cancer.People with CVID may start experiencing signs and symptoms of the disorder anytime between childhood and adulthood; most people with CVID are diagnosed in their twenties or thirties. The life expectancy of individuals with CVID varies depending on the severity and frequency of illnesses they experience. Most people with CVID live into adulthood.There are many different types of CVID that are distinguished by genetic cause. People with the same type of CVID may have varying signs and symptoms. [from GTR]

MedGen UID:
762276
Concept ID:
C3542922
Disease or Syndrome
7.

Afibrinogenemia, congenital

Inherited disorders of fibrinogen affect either the quantity (afibrinogenemia and hypofibrinogenemia; 202400) or the quality (dysfibrinogenemia; 616004) of the circulating fibrinogen or both (hypodysfibrinogenemia; see 616004). Afibrinogenemia is characterized by the complete absence of immunoreactive fibrinogen. Bleeding due to afibrinogenemia usually manifests in the neonatal period, with 85% of cases presenting umbilical cord bleeding, but a later age of onst is not unusual. Bleeding may occur in the skin, gastrointestinal tract, genitourinary tract, or the central nervous system, with intracranial hemorrhage being reported as the major cause of death. Patients are susceptible to spontaneous rupture of the spleen. Menstruating women may experience menometrorrhagia. First-trimester abortion is common. Both arterial and venous thromboembolic complications have been reported (summary by de Moerloose and Neerman-Arbez, 2009). Hypofibrinogenemia is characterized by reduced amounts of immunoreactive fibrinogen. Patients are often heterozygous carriers of afibrinogenemia mutations and are usually asymptomatic. However, they may bleed when exposed to trauma or if they have a second associated hemostatic abnormality. Women may experience miscarriages. Liver disease occurs in rare cases (summary by de Moerloose and Neerman-Arbez, 2009). [from GTR]

MedGen UID:
749036
Concept ID:
C2584774
Disease or Syndrome
8.

Thrombophilia due to protein S deficiency, autosomal recessive

Autosomal recessive thrombophilia due to protein S deficiency is a very rare and severe hematologic disorder resulting in thrombosis and secondary hemorrhage usually beginning in early infancy. Some affected individuals develop neonatal purpura fulminans, multifocal thrombosis, or intracranial hemorrhage (Pung-amritt et al., 1999; Fischer et al., 2010), whereas others have recurrent thromboses later in childhood (Comp et al., 1984). See also autosomal dominant thrombophilia due to protein S deficiency (THPH5; 612336), a less severe disorder caused by heterozygous mutation in the PROS1 gene. [from GTR]

MedGen UID:
482722
Concept ID:
C3281092
Disease or Syndrome
9.

Pregnancy loss, recurrent, susceptibility to, 2

Miscarriage, the commonest complication of pregnancy, is the spontaneous loss of a pregnancy before the fetus has reached viability. The term therefore includes all pregnancy losses from the time of conception until 24 weeks of gestation. Recurrent miscarriage, defined as 3 or more consecutive pregnancy losses, affects about 1% of couples; when defined as 2 or more losses, the scale of the problem increases to 5% of all couples trying to conceive (summary by Rai and Regan, 2006). Pregnancy losses have traditionally been designated 'spontaneous abortions' if they occur before 20 weeks' gestation and 'stillbirths' if they occur after 20 weeks. Subtypes of spontaneous abortions can be further distinguished on the basis of embryonic development and include anembryonic loss in the first 5 weeks after conception (so-called 'blighted ovum'), embryonic loss from 6 to 9 weeks' gestation, and fetal loss from 10 weeks' gestation through the remainder of the pregnancy. These distinctions are important because the causes of pregnancy loss vary over gestational ages, with anembryonic losses being more likely to be associated with chromosomal abnormalities, for example. Possible etiologies for recurrent pregnancy loss include uterine anatomic abnormalities, cytogenetic abnormalities in the parents or fetus, single gene disorders, thrombophilic conditions, and immunologic or endocrine factors as well as environmental or infectious agents (summary by Warren and Silver, 2008). [from GTR]

MedGen UID:
482302
Concept ID:
C3280672
Finding
10.

Complement component 4b deficiency

MedGen UID:
482271
Concept ID:
C3280641
Disease or Syndrome
11.

Complement component 9 deficiency

MedGen UID:
462539
Concept ID:
C3151189
Disease or Syndrome
12.

MASP2 deficiency

MASP2 deficiency, classically defined as MASP2 protein level of less than 100 ng/ml, occurs in about 4% of Caucasians and up to 18% of some African populations. Some MASP2-deficient individuals have increased risk of infection or autoimmune disease, but most are asymptomatic. MASP2 plays a role in activation of the lectin pathway of the complement system; deficiency may thus lead to defects in the complement system (summary by Thiel et al., 2007 and Sokolowska et al., 2015). For a discussion of genetic heterogeneity of lectin complement activation pathway defects, see LCAPD1 (614372). [from GTR]

MedGen UID:
462435
Concept ID:
C3151085
Disease or Syndrome
13.

Complement component c1s deficiency

MedGen UID:
462428
Concept ID:
C3151078
Disease or Syndrome
14.

Complement component 3 deficiency, autosomal recessive

The main clinical manifestation of primary C3 deficiency is childhood-onset of recurrent bacterial infections, mainly caused by gram-negative bacteria, such as Neisseria meningitidis, Enterobacter aerogenes, Haemophilus influenzae, and Escherichia coli; infections with gram-positive bacteria also occur. Infections in the upper and lower respiratory tract, including pneumonia, episodes of sinusitis, tonsillitis, and otitis, are the most frequent consequence of the C3 deficiency. Approximately 26% of patients with C3 deficiency develop immune complex-mediated autoimmune diseases resembling systemic lupus erythematosus (see 152700), and about 26% of patients develop mesangiocapillary or membranoproliferative glomerulonephritis, resulting in renal failure (summary by Reis et al., 2006). [from GTR]

MedGen UID:
462421
Concept ID:
C3151071
Disease or Syndrome
15.

C1q deficiency

C1q deficiency is a rare autosomal recessive disorder characterized by recurrent skin lesions, chronic infections, and an increased risk of autoimmune diseases, particularly systemic lupus erythematosus (SLE; see 152700) or SLE-like diseases. It has also been associated with chronic glomerulonephritis and renal failure. C1q deficiency presents in 2 different forms, absent C1q protein or presence of a dysfunctional molecule (summary by Topaloglu et al., 1996 and Vassallo et al., 2007). [from GTR]

MedGen UID:
462252
Concept ID:
C3150902
Disease or Syndrome
16.

Common variable immunodeficiency 2

Common variable immune deficiency (CVID) is a disorder that impairs the immune system. People with CVID are highly susceptible to infection from foreign invaders such as bacteria, or more rarely, viruses and often develop recurrent infections, particularly in the lungs, sinuses, and ears. Pneumonia is common in people with CVID. Over time, recurrent infections can lead to chronic lung disease. Affected individuals may also experience infection or inflammation of the gastrointestinal tract, which can cause diarrhea and weight loss. Abnormal accumulation of immune cells causes enlarged lymph nodes (lymphadenopathy) or an enlarged spleen (splenomegaly) in some people with CVID. Immune cells can accumulate in other organs, forming small lumps called granulomas.Approximately 25 percent of people with CVID have an autoimmune disorder, which occurs when the immune system malfunctions and attacks the body's tissues and organs. The blood cells are most frequently affected by autoimmune attacks in CVID; the most commonly occurring autoimmune disorders are immune thrombocytopenia purpura, which is an abnormal bleeding disorder caused by a decrease in cell fragments involved in blood clotting called platelets, and autoimmune hemolytic anemia, which results in premature destruction of red blood cells. Other autoimmune disorders such as rheumatoid arthritis can occur. Individuals with CVID also have a greater than normal risk of developing certain types of cancer, including a cancer of immune system cells called non-Hodgkin lymphoma and less frequently, stomach (gastric) cancer.People with CVID may start experiencing signs and symptoms of the disorder anytime between childhood and adulthood; most people with CVID are diagnosed in their twenties or thirties. The life expectancy of individuals with CVID varies depending on the severity and frequency of illnesses they experience. Most people with CVID live into adulthood.There are many different types of CVID that are distinguished by genetic cause. People with the same type of CVID may have varying signs and symptoms. [from GTR]

MedGen UID:
461704
Concept ID:
C3150354
Disease or Syndrome
17.

Complement component 2 deficiency

Complement component 2 deficiency is a disorder that causes the immune system to malfunction, resulting in a form of immunodeficiency. Immunodeficiencies are conditions in which the immune system is not able to protect the body effectively from foreign invaders such as bacteria and viruses. People with complement component 2 deficiency have a significantly increased risk of recurrent bacterial infections, specifically of the lungs (pneumonia), the membrane covering the brain and spinal cord (meningitis), and the blood (sepsis), which may be life-threatening. These infections most commonly occur in infancy and childhood and become less frequent in adolescence and adulthood.Complement component 2 deficiency is also associated with an increased risk of developing autoimmune disorders such as systemic lupus erythematosus (SLE) or vasculitis. Autoimmune disorders occur when the immune system malfunctions and attacks the body's tissues and organs. Between 10 and 20 percent of individuals with complement component 2 deficiency develop SLE. Females with complement component 2 deficiency are more likely to have SLE than affected males, but this is also true of SLE in the general population.The severity of complement component 2 deficiency varies widely. While some affected individuals experience recurrent infections and other immune system difficulties, others do not have any health problems related to the disorder. [from GTR]

MedGen UID:
461625
Concept ID:
C3150275
Disease or Syndrome
18.

Complement component c1r/c1s deficiency

Lack of production of either functional C1r or C1s protein, due to a genetic defect. Approximately 60% of patients with a C1r/C1s deficiency will develop a severe systemic lupus erythematosus at an early age. Patients also present with frequent sinopulmonary infections often with Streptococcus pneumoniae. [from NCI]

MedGen UID:
461624
Concept ID:
C3150274
Disease or Syndrome
19.

Cromer blood group system

MedGen UID:
450551
Concept ID:
C1292305
Body System
20.

Warfarin response

Warfarin is an oral anti-coagulant used world-wide to treat and prevent thrombotic disorders. While it is highly effective, it has a very narrow therapeutic index making it difficult to dose correctly. Genetic variants in both cytochrome P450-2C9 (CYP2C9) and vitamin K-epoxide reductase complex (VKORC1) enzymes, along with non-genetic factors, are known to affect warfarin dose variability. Patients with specific variants in the gene CYP2C9 (the primary warfarin-metabolizing enzyme), such as CYP2C9*2 and CYP2C9*3, may require a lower dose of warfarin as compared to patients without these variants. Patients with a specific variant in VKORC1 (the target enzyme of warfarin), known as -1639G>A or rs9923231, may require a lower warfarin dose as compared to patients who do not have this variant. The combination of CYP2C9 and VKORC1 genetic variants, along with clinical factors, can put some patients at risk for adverse events such as bleeding. Guidelines regarding the use of pharmacogenomic tests in dosing for warfarin have been published in Clinical Pharmacology and Therapeutics by the Clinical Pharmacogenetics Implementation Consortium (CPIC) and are available on the PharmGKB website. [from GTR]

MedGen UID:
450501
Concept ID:
CN078029
Sign or Symptom
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