| Agammaglobulinemia-microcephaly-craniosynostosis-severe dermatitis syndrome | |
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| Other names | Agammaglobulinemia, microcephaly, and severe dermatitis |
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Agammaglobulinemia-microcephaly-craniosynostosis-severe dermatitis syndrome is a rare autosomal recessive syndromic form of agammaglobulinemia that is caused by profound B-cell depletion with normal T-cell numbers. [1] The condition was first identified in a 2006 report. [2] [3]
Features of this condition include: [1]
Distal joint contractures, renal/genitourinary anomalies, and mild cerebral atrophy have also been reported.
This condition is known to be genetic, but the gene(s) responsible are yet to be identified.
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders are the most common, the term is mostly used when discussing disorders with a single genetic cause, either in a gene or chromosome. The mutation responsible can occur spontaneously before embryonic development, or it can be inherited from two parents who are carriers of a faulty gene or from a parent with the disorder. When the genetic disorder is inherited from one or both parents, it is also classified as a hereditary disease. Some disorders are caused by a mutation on the X chromosome and have X-linked inheritance. Very few disorders are inherited on the Y chromosome or mitochondrial DNA.
Microcephaly is a medical condition involving a smaller-than-normal head. Microcephaly may be present at birth or it may develop in the first few years of life. Brain development is often affected; people with this disorder often have an intellectual disability, poor motor function, poor speech, abnormal facial features, seizures and dwarfism.
Waardenburg syndrome is a group of rare genetic conditions characterised by at least some degree of congenital hearing loss and pigmentation deficiencies, which can include bright blue eyes, a white forelock or patches of light skin. These basic features constitute type 2 of the condition; in type 1, there is also a wider gap between the inner corners of the eyes called telecanthus, or dystopia canthorum. In type 3, which is rare, the arms and hands are also malformed, with permanent finger contractures or fused fingers, while in type 4, the person also has Hirschsprung's disease. There also exist at least two types that can result in central nervous system (CNS) symptoms such as developmental delay and muscle tone abnormalities.
X-linked agammaglobulinemia (XLA) is a rare genetic disorder discovered in 1952 that affects the body's ability to fight infection. As the form of agammaglobulinemia that is X-linked, it is much more common in males. In people with XLA, the white blood cell formation process does not generate mature B cells, which manifests as a complete or near-complete lack of proteins called gamma globulins, including antibodies, in their bloodstream. B cells are part of the immune system and normally manufacture antibodies, which defend the body from infections by sustaining a humoral immunity response. Patients with untreated XLA are prone to develop serious and even fatal infections. A mutation occurs at the Bruton's tyrosine kinase (Btk) gene that leads to a severe block in B cell development and a reduced immunoglobulin production in the serum. Btk is particularly responsible for mediating B cell development and maturation through a signaling effect on the B cell receptor BCR. Patients typically present in early childhood with recurrent infections, in particular with extracellular, encapsulated bacteria. XLA is deemed to have a relatively low incidence of disease, with an occurrence rate of approximately 1 in 200,000 live births and a frequency of about 1 in 100,000 male newborns. It has no ethnic predisposition. XLA is treated by infusion of human antibody. Treatment with pooled gamma globulin cannot restore a functional population of B cells, but it is sufficient to reduce the severity and number of infections due to the passive immunity granted by the exogenous antibodies.
Nijmegen breakage syndrome (NBS) is a rare autosomal recessive congenital disorder causing chromosomal instability, probably as a result of a defect in the double Holliday junction DNA repair mechanism and/or the synthesis dependent strand annealing mechanism for repairing double strand breaks in DNA.
SCARF syndrome is a rare syndrome characterized by skeletal abnormalities, cutis laxa, craniostenosis, ambiguous genitalia, psychomotor retardation, and facial abnormalities. These characteristics are what make up the acronym SCARF. It shares some features with Lenz-Majewski hyperostotic dwarfism. It is a very rare disease with an incidence rate of approximately one in a million newborns. It has been clinically described in two males who were maternal cousins, as well as a 3-month-old female. Babies affected by this syndrome tend to have very loose skin, giving them an elderly facial appearance. Possible complications include dyspnea, abdominal hernia, heart disorders, joint disorders, and dislocations of multiple joints. It is believed that this disease's inheritance is X-linked recessive.
Dubowitz syndrome is a rare genetic disorder characterized by microcephaly, stunted growth, and a receding chin. Symptoms vary among patients, but other characteristics include a soft, high-pitched voice, partial webbing of the fingers and toes, palate deformations, genital abnormalities, language difficulties, and an aversion to crowds. The pathogenesis of the disease is yet to be identified, and no medical tests can definitively diagnose the disease. The primary method of diagnosis is to identify facial phenotypes. Since it was first described in 1965 by English physician Victor Dubowitz, over 140 cases have been reported worldwide. Although the majority of cases have been reported from the United States, Germany, and Russia, the disorder appears to affect both genders and all ethnicities equally.
Antley–Bixler syndrome is a rare, severe autosomal recessive congenital disorder characterized by malformations and deformities affecting the majority of the skeleton and other areas of the body.
Marden–Walker syndrome (MWS) is a rare autosomal recessive congenital disorder. It is characterized by blepharophimosis, microcephaly, micrognathia, multiple joint contractures, arachnodactyly, camptodactyly, kyphoscoliosis and delayed motor development and is often associated with cystic dysplastic kidneys, dextrocardia, Dandy–Walker malformation and agenesis of corpus callosum.
Warsaw breakage syndrome is a rare genetic condition. Fewer than 10 cases have been reported by 2018. Its clinical manifestations affect several organ systems, and includes microcephaly and severe growth retardation among others.
Cernunnos deficiency is a form of combined immunodeficiency characterized by microcephaly, due to mutations in the NHEJ1 gene, it is inherited via autosomal recessive manner Management for this condition is antiviral prophylaxis and antibiotic treatment
Neu–Laxova syndrome is a rare autosomal recessive disorder characterized by severe intrauterine growth restriction and multiple congenital malformations. Neu–Laxova syndrome is a very severe disorder, leading to stillbirth or death shortly after birth. It was first described by Dr. Richard Neu in 1971 and Dr. Renata Laxova in 1972 as a lethal disorder in siblings with multiple malformations. Neu–Laxova syndrome is an extremely rare disorder with less than 100 cases reported in medical literature.
Sanjad-Sakati syndrome is a rare autosomal recessive genetic condition seen in offspring of Middle Eastern origin. It was first described in Saudi Arabia, but has been seen in Qatari, Kuwaiti, Omani and other children from the Middle East as well as elsewhere. The condition is caused by mutations or deletions in the TBCE gene of Chromosome No.1.
RIDDLE syndrome is a rare genetic syndrome. The name is an acronym for Radiosensitivity, ImmunoDeficiency Dysmorphic features and LEarning difficulties.
Strømme syndrome is a very rare autosomal recessive genetic condition characterised by intestinal atresia, eye abnormalities and microcephaly. The intestinal atresia is of the "apple-peel" type, in which the remaining intestine is twisted around its main artery. The front third of the eye is typically underdeveloped, and there is usually moderate developmental delay. Less common features include an atrial septal defect, increased muscle tone or skeletal abnormalities. Physical features may include short stature, large, low-set ears, a small jaw, a large mouth, epicanthic folds, or fine, sparse hair.
Autosomal dominant intellectual disability-craniofacial anomalies-cardiac defects syndrome is a rare genetic disorder which is characterized by multi-systemic symptoms primarily affecting the intellect and post-natal development.
Sloping forehead is a condition in which the forehead is objectively vertically inclined more than two standard deviations, or the forehead shows subjectively excessive posterior sloping when viewed in profile.
Craniosynostosis-fibular aplasia syndrome is a rare syndrome characterized by bicoronal craniosynostosis, absent fibula, cryptorchidism, and bilateral simian creases.
Aprosencephaly cerebellar dysgenesis is a rare, non-syndromic central nervous system malformation characterized by the absence of the telencephalon and diencephalic structures. These are often combined with severe abnormalities in the mesencephalon and cerebellum.