A rare, complex chromosomal duplication/inversion in the region 15q11.2-q13.1 characterized by early central hypotonia, global developmental delay and intellectual deficit, autistic behavior, and seizures. Epidemiology Prevalence at birth is estimated at 1 in 30,000 but may be an underestimate. In patients with developmental concerns (developmental delay, intellectual disability, or autism spectrum disorder) or multiple congenital anomalies, the prevalence of partial tetrasomy of chromosome 15 is estimated to range between 1/253-584. There is an observed male predilection of 2:1. Clinical description Presentation is typically with neonatal hypotonia, feeding difficulties and gross motor delay. Global developmental delay is typical in early childhood with speech and language particularly affected.

For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip/palate (CL/P), see 119530. Mapping Stein et al. (1995) tested linkage of 22 candidate genes to CL/P in 11 multigenerational families, and excluded 21 of these candidates. APOC2 (608083), which is located at 19q13.1 (or 19q13.2) and which is linked to the protooncogene BCL3 (109560), gave suggestive evidence for linkage to CL/P. The study was expanded to include a total of 39 multigenerational CL/P families. Linkage was tested in all the families, using an anonymous marker, D19S178, and intragenic markers in BCL3 and APOC2.

Description Nonsyndromic cleft lip with or without cleft palate is a complex disease with a wide phenotypic spectrum ranging from notches of the vermilion and/or grooves in the philtrum to complete unilateral and bilateral clefts of the lip and palate (summary by Neiswanger et al., 2007). Genetic Heterogeneity of Orofacial Cleft Isolated cleft lip with or without cleft palate (CL/P) is genetically heterogeneous. The OFC1 locus has been mapped to chromosome 6p24. Other CL/P loci have been mapped to 2p13 (OFC2; 602966), 19q13 (OFC3; 600757), 4q (OFC4; 608371), 13q33.1-q34 (OFC9; 610361), 8q24.3 (OFC12; 612858), and 1p33 (OFC13; 613857). OFC5 (608874) is caused by mutation in the MSX1 gene (142983) on 4p16; OFC6 (608864) is associated with variation in an enhancer of the IRF6 gene (607199) on 1q; OFC7 (see 225060) is associated with mutation in the NECTIN1 gene (600644) on 11q23; OFC8 (618149) is caused by mutation in the TP63 gene (603273) on 3q28; OFC10 (613705) is associated with haploinsufficiency of the SUMO1 gene (601912) on 2q33; OFC11 (600625) is caused by mutation in the BMP4 gene (112262) on 14q22; OFC14 (615892) is associated with a 273-kb deleted region on 1p31; and OFC15 (616788) is caused by mutation in the DLX4 gene (601911) on 17q21. A common polymorphism in the MTR gene (156570.0008) has been associated with susceptibility to orofacial clefting.

A number sign (#) is used with this entry because of evidence that orofacial cleft-8 (OFC8) is caused by heterozygous mutation in the TP63 gene (603273) on chromosome 3q28. Clinical Features Leoyklang et al. (2006) reported a 4-year-old Thai girl with a surgically repaired bilateral complete cleft lip. Her parents were unaffected. Basha et al. (2018) reported a family (CLP-1055) in which the proband and his father had orofacial cleft. The son had a unilateral, right-sided cleft lip. He had no limb anomaly, no ectodermal dysplasia, and no cardiac malformations. Follow-up until the age of 3.5 years showed growth and development within normal limits.

Cleft lip and palate Other names Hare-lip, cleft lip and palate Child with cleft lip and palate. Specialty Otorhinolaryngology , pediatrics Symptoms Opening in the upper lip that may extend into the nose or palate [1] Complications Feeding problems, speech problems, hearing problems, frequent ear infections [1] Usual onset Present at birth [1] Causes Usually unknown [1] Risk factors Smoking during pregnancy , diabetes , obesity , older mother , certain medications [1] [2] Treatment Surgery, speech therapy , dental care [1] Prognosis Good (with treatment) [1] Frequency 1.5 per 1000 births ( developed world ) [2] Deaths 3,800 (2017) [3] Cleft lip and cleft palate , also known as orofacial cleft , is a group of conditions that includes cleft lip, cleft palate, and both together. [1] [2] A cleft lip contains an opening in the upper lip that may extend into the nose. [1] The opening may be on one side, both sides, or in the middle. [1] A cleft palate occurs when the roof of the mouth contains an opening into the nose . [1] These disorders can result in feeding problems, speech problems, hearing problems, and frequent ear infections . [1] Less than half the time the condition is associated with other disorders. [1] Cleft lip and palate are the result of tissues of the face not joining properly during development . [1] As such, they are a type of birth defect . [1] The cause is unknown in most cases. [1] Risk factors include smoking during pregnancy , diabetes , obesity , an older mother , and certain medications (such as some used to treat seizures ). [1] [2] Cleft lip and cleft palate can often be diagnosed during pregnancy with an ultrasound exam . [1] A cleft lip or palate can be successfully treated with surgery. [1] This is often done in the first few months of life for cleft lip and before eighteen months for cleft palate. [1] Speech therapy and dental care may also be needed. [1] With appropriate treatment, outcomes are good. [1] Cleft lip and palate occurs in about 1 to 2 per 1000 births in the developed world . [2] Cleft lip is about twice as common in males as females, while cleft palate without cleft lip is more common in females. [2] In 2017, it resulted in about 3,800 deaths globally, down from 14,600 deaths in 1990. [3] [4] The condition was formerly known as a "hare-lip" because of its resemblance to a hare or rabbit, but that term is now generally considered to be offensive. [5] Contents 1 Signs and symptoms 1.1 Cleft lip 1.2 Cleft palate 1.3 Teeth 1.4 Complications 1.5 Psychosocial issues 2 Cause 2.1 Genetics 2.1.1 Syndromes 2.1.2 Specific genes 2.2 Environmental factors 3 Diagnosis 3.1 Classification 3.2 Prenatal diagnosis 4 Treatment 4.1 Cleft lip 4.1.1 Pre-surgical devices 4.2 Cleft palate 4.2.1 Other surgeries 4.3 Speech 4.4 Hearing 4.5 Feeding 4.5.1 Breast-feeding 4.5.2 Alternative Feeding Methods 4.6 Treatment schedule 4.7 Cleft team 4.8 Outcomes assessment 5 Epidemiology 6 Society and culture 6.1 Abortion controversy 6.2 Works of fiction 6.3 Notable cases 7 Other animals 8 See also 9 References 10 External links Signs and symptoms Cleft lip If the cleft does not affect the palate structure of the mouth, it is referred to as cleft lip. Cleft lip is formed in the top of the lip as either a small gap or an indentation in the lip (partial or incomplete cleft), or it continues into the nose (complete cleft). Lip cleft can occur as a one-sided (unilateral) or two-sided (bilateral) condition. It is due to the failure of fusion of the maxillary prominence and medial nasal processes (formation of the primary palate).

For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip/palate (CL/P), see 119530. Mapping Using 13 microsatellite markers specific for 4q in a study of 7 of 8 persons with CL/P in a 5-generation family, Beiraghi et al. (1994) found evidence of linkage between the phenotype and 2 markers, D4S175 (maximum lod = 2.27 at theta = 0) and D4S192 (maximum lod = 1.93 at theta = 0). No linkage with markers on chromosome 6 was found in this family. In linkage studies of 36 multiplex Chinese families with CL/P, Marazita et al. (2002) found the highest multipoint heterogeneity lod score (2.5) at 4q with marker D4S1629 under a recessive inheritance model. In addition, there was a positive identity-by-descent result with D4S2361. Cytogenetics In a father and son with cleft lip, Beiraghi et al. (2003) identified a balanced pericentric inversion of chromosome 4, inv(4)(p13q21).

For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip/palate (CL/P), see 119530. Mapping Ardinger et al. (1989) observed a significant association between 2 RFLPs at the transforming growth factor-alpha (TGFA; 190170) locus on chromosome 2p13 and the occurrence of clefting. The authors suggested that either the TGFA gene or DNA sequences adjacent to the locus contribute to the development of some cases of cleft lip with or without cleft palate in humans. However, in a study of 7 families with CL/P segregating in a dominant manner, the TGFA haplotype associations reported by Ardinger et al. (1989) were not seen, and in 1 family clefting did not cosegregate with TGFA, thus ruling out tight linkage (Hecht et al. (1990, 1991)). In 96 unrelated patients with nonsyndromic CL/P, Chenevix-Trench et al. (1991) confirmed the existence of an excess frequency of the same TaqI allele found by Ardinger et al. (1989).

A number sign (#) is used with this entry because of evidence that Rapp-Hodgkin syndrome is caused by heterozygous mutation in the TP63 gene (603273) on chromosome 3q27. Allelic disorders with overlapping features include EEC3 (604292), limb-mammary syndrome (LMS; 603543), ADULT syndrome (103285), AEC syndrome (106260), and SHFM4 (605289). Clinical Features Rapp and Hodgkin (1968) described mother, son, and daughter with anhidrotic ectodermal dysplasia, cleft lip, and cleft palate. The combination had not previously been recorded. The nose was unusually narrow and the mouth small. Similar cases were reported by Summitt and Hiatt (1971) and Wannarachue et al. (1972).

A number sign (#) is used with this entry because of evidence that orofacial cleft-11 (OFC11) is caused by heterozygous mutation in the BMP4 gene (112262) on chromosome 14q22. For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip with or without cleft palate, see OFC1 (119530). Description Congenital 'healed' cleft lip (CHCL) is an unusual anomaly consisting of a paramedian 'scar' of the upper lip with an appearance suggesting that a typical cleft lip was corrected in utero. The CHCL is frequently associated with an ipsilateral notch in the vermilion border and a 'collapsed' nostril (Castilla and Martinez-Frias, 1995). Clinical Features Castilla and Martinez-Frias (1995) presented 25 CHCL cases, 18 of which represented an isolated malformation found among the 3,950,715 births examined in 2 similar birth defect registries, 1 in Spain and 1 in Latin America.

A number sign (#) is used with this entry because of evidence that cleft lip/palate-ectodermal dysplasia syndrome (CLPED1) is caused by homozygous mutation in the PVRL1 gene (NECTIN1; 600644) on chromosome 11q23. Mutation in the PVRL1 gene has also been found in a form of orofacial cleft (OFC7). Clinical Features Zlotogora et al. (1987) reported 2 sibs with a syndrome including cleft lip and palate, sparse scalp hair, malformed protruding ears, and partial syndactyly of the fingers and toes. An older sib also had mental retardation and pili torti. The parents were consanguineous. In 2 Turkish sibs, products of a second-cousin marriage, Ogur and Yuksel (1988) found the combination of tetramelic syndactyly, ectodermal dysplasia, cleft lip and palate, renal anomalies, and mental retardation.

A number sign (#) is used with this entry because of evidence that orofacial cleft-10 (OFC10) is caused by mutation in the SUMO1 gene (601912) on chromosome 2q33. One such patient has been reported. For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip/palate (CL/P), see 119530. Clinical Features Alkuraya et al. (2006) identified a 5-year-old Caucasian girl with a unilateral cleft lip and palate (primary and secondary) who was otherwise phenotypically normal. Her karyotype was 46,XX,t(2;8)(q33.1;q24.3), and array CGH analysis was normal. Molecular Genetics Alkuraya et al. (2006) showed that the balanced translocation in a girl with orofacial cleft disrupted the SUMO1 gene, leading to haploinsufficiency confirmed by RNA and protein studies (601912.0001).

A number sign (#) is used with this entry because of evidence that orofacial cleft-15 (OFC15) is caused by mutation in the DLX4 gene (601911) on chromosome 17q21. One such family has been reported. For a discussion of genetic heterogeneity of nonsyndromic cleft/lip palate (CL/P), see OFC1 (119530). Clinical Features Wu et al. (2015) studied a Hispanic mother and son with bilateral cleft lip and palate and minor dysmorphic features. The mother had CL/P repaired in early childhood. On examination at 16 years of age, her speech was hyponasal and she exhibited high anterior hairline, sparse eyebrows, prominent ears, hypertelorism, euryblepharon, lagophthalmos, and mild ectropion of the lower eyelids. She also had marked midface hypoplasia with an anterior crossbite, and the lateral incisors were missing.

A number sign (#) is used with this entry because of evidence that susceptibility to orofacial cleft-6 (OFC6) is conferred by variation in an enhancer of the IRF6 gene (607199) on chromosome 1q32. For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic CL/P, see 119530. Mapping In van der Woude syndrome (VWS; 119300), lower lip pits are associated with CL/P or cleft palate only. Since none of these traits is present in all persons who carry the VWS mutation, some individual or familial VWS cases, especially those lacking lip pits, are indiscernible from nonsyndromic CL/P, raising the question of whether allelic variation at the VWS locus could underlie nonsyndromic CL/P. By linkage studies, Hecht et al. (1992) excluded the region of chromosome 1q which carries the van der Woude syndrome as the site of the mutation in this disorder and in isolated cleft palate.

Cleft lip and palate is a fissure type embryopathy extending across the upper lip, nasal base, alveolar ridge and the hard and soft palate. Epidemiology The annual incidence ranges from 1/2,000 to 1/5,000 births. Cleft lip and palate is seen twice as commonly in boys. Clinical description The malformation is the association, in varying degrees, of cleft lip/alveolus and cleft palate (see these terms). The lip and alveolus anomaly is paramedian and is located at the philtrum level for the lip and at the level of the upper lateral incisors for the alveolar ridge. It involves a cutaneous, muscular and mucosal interruption in the lip in addition to a nostril and nasal septum deformity and a gap in the alveolar bone and dental arch.

For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic CL/P, see 119530. Mapping Birnbaum et al. (2009) conducted a genomewide association study involving 224 unrelated patients of Central European origin with nonsyndromic cleft lip with or without cleft palate (NSCL/P) and identified a 640-kb region on chromosome 8q24.21 containing 3 markers that reached genomewide significance. Fine mapping of the 640-kb region in 462 unrelated NSCL/P cases revealed a SNP (rs987525) that was significantly associated with the disorder (p = 3.34 x 10(-24); odds ratio, 2.57 for heterozygotes and 6.05 for homozygotes). The calculated population attributable risk for this marker was 0.41, suggesting that this represents a major susceptibility locus for NSCL/P. In independent Estonian and Lithuanian samples, Nikopensius et al. (2009) replicated the previously reported association between rs987525 and nonsyndromic oral clefting, obtaining highly significant results in both groups (p = 5.97 x 10(-5) and p = 1.6 x 10(-5), respectively).

For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic cleft lip/palate (CL/P), see 119530. Mapping In 2 Indian pedigrees with isolated, nonsyndromic cleft lip with or without cleft palate segregating as an autosomal dominant trait, Radhakrishna et al. (2006) demonstrated linkage to 13q33.1-q34, with a nonparametric linkage score of 5.57 at marker rs1830756. Haplotype analysis with informative crossovers enabled the mapping of a CL/P locus to a region of approximately 20.17 cM (7.42 Mb) between SNPs rs951095 and rs726455. The phenotype was variable, ranging from unilateral to bilateral CL/P. The authors noted that CL/P is very common in patients with trisomy involving all or part of chromosome 13 (Berge et al., 2001).

A number sign (#) is used with this entry because of evidence that orofacial cleft-5 (OFC5) is caused by mutation in the MSX1 gene (142983) on chromosome 4p16. For a phenotypic description and a discussion of genetic heterogeneity of nonsyndromic CL/P, see 119530. Molecular Genetics With both case-control- and nuclear family-based approaches, Lidral et al. (1998) screened candidate genes for clefting in both the CL/P CPO of the nonsyndromic type. Significant linkage disequilibrium was found between CL/P and both MSX1 and TGFB3 (190230) and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2 (126255), MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of CL/P patients.

Sudden infant death syndrome (SIDS) is the unexpected, sudden death of a child under age 1 which cannot be explained after a thorough investigation is conducted. Infants who are affected by the condition generally appear healthy with no suspicious signs and symptoms prior to the incident. It is the leading cause of death in infants age 1 to 12 months old. The exact underlying cause of SIDS is unknown; however, scientists suspect that it is likely a multifactorial condition (associated with the effects of multiple genes in combination with lifestyle and environmental factors). Although there is no guaranteed way to prevent SIDS, the American Academy of Pediatrics has a published list of recommendations for risk reduction. Please click on the link to access this resource.

Sudden unexplained death of a child of less than one year of age Sudden infant death syndrome Other names Cot death, crib death Safe to Sleep logo Specialty Pediatrics Symptoms Death of a child less than one year of age [1] Usual onset Sudden [1] Causes Unknown [1] Risk factors Sleeping on the stomach or side, overheating, exposure to tobacco smoke , bed sharing [2] [3] Diagnostic method No cause found after an investigation and autopsy [4] Differential diagnosis Infections , genetic disorders , heart problems, child abuse [2] Prevention Putting newborns on their back to sleep, pacifier , breastfeeding , immunization [5] [6] [7] Treatment Support for families [2] Frequency 1 in 1,000–10,000 [2] Sudden infant death syndrome ( SIDS ), also known as cot death or crib death , is the sudden unexplained death of a child of less than one year of age. [1] Diagnosis requires that the death remain unexplained even after a thorough autopsy and detailed death scene investigation. [4] SIDS usually occurs during sleep . [2] Typically death occurs between the hours of 00:00 and 09:00. [8] There is usually no noise or evidence of struggle. [9] SIDS remains the leading cause of infant mortality in Western countries, contributing to half of all post-neonatal deaths. [10] The exact cause of SIDS is unknown. [3] The requirement of a combination of factors including a specific underlying susceptibility, a specific time in development, and an environmental stressor has been proposed. [2] [3] These environmental stressors may include sleeping on the stomach or side, overheating, and exposure to tobacco smoke . [3] Accidental suffocation from bed sharing (also known as co-sleeping) or soft objects may also play a role. [2] [11] Another risk factor is being born before 39 weeks of gestation . [7] SIDS makes up about 80% of sudden and unexpected infant deaths (SUIDs). [2] The other 20% of cases are often caused by infections , genetic disorders , and heart problems. [2] While child abuse in the form of intentional suffocation may be misdiagnosed as SIDS, this is believed to make up less than 5% of cases. [2] The most effective method of reducing the risk of SIDS is putting a child less than one year old on their back to sleep. [7] Other measures include a firm mattress separate from but close to caregivers, no loose bedding, a relatively cool sleeping environment, using a pacifier , and avoiding exposure to tobacco smoke. [5] Breastfeeding and immunization may also be preventive. [5] [6] Measures not shown to be useful include positioning devices and baby monitors . [5] [6] Evidence is not sufficient for the use of fans. [5] Grief support for families affected by SIDS is important, as the death of the infant is sudden, without witnesses, and often associated with an investigation. [2] Rates of SIDS vary nearly tenfold in developed countries from one in a thousand to one in ten thousand. [2] [12] Globally, it resulted in about 19,200 deaths in 2015, down from 22,000 deaths in 1990. [13] [14] SIDS was the third leading cause of death in children less than one year old in the United States in 2011. [15] It is the most common cause of death between one month and one year of age. [7] About 90% of cases happen before six months of age, with it being most frequent between two months and four months of age. [2] [7] It is more common in boys than girls. [7] Rates have decreased in areas with "safe sleep campaigns" by up to 80%. [12] Play media Video explanation Contents 1 Definition 1.1 Age 2 Risk factors 2.1 Tobacco smoke 2.2 Sleeping 2.3 Breastfeeding 2.4 Pregnancy and infant factors 2.5 Genetics 2.6 Alcohol 2.7 Other 3 Diagnosis 3.1 Differential diagnosis 4 Prevention 4.1 Sleep positioning 4.2 Pacifiers 4.3 Bedding 4.4 Vaccination 5 Management 6 Epidemiology 6.1 Race 7 Society and culture 8 See also 9 References 10 Further reading 11 External links Definition [ edit ] SIDS is a diagnosis of exclusion and should be applied to only those cases in which an infant's death is sudden and unexpected, and remains unexplained after the performance of an adequate postmortem investigation, including: an autopsy (by an experienced pediatric pathologist , if possible); investigation of the death scene and circumstances of the death; and exploration of the medical history of the infant and family. After investigation, some of these infant deaths are found to be caused by suffocation, hyperthermia or hypothermia , neglect or some other defined cause. [16] Australia and New Zealand are shifting to the term "sudden unexpected death in infancy" (SUDI) for professional, scientific, and coronial clarity. The term SUDI is now often used instead of sudden infant death syndrome (SIDS) because some coroners prefer to use the term 'undetermined' for a death previously considered to be SIDS. This change is causing diagnostic shift in the mortality data. [17] In addition, the U.S. Centers for Disease Control and Prevention (CDC) has recently proposed that such deaths be called "sudden unexpected infant deaths" (SUID) and that SIDS is a subset of SUID. [18] Age [ edit ] SIDS has a 4-parameter lognormal age distribution that spares infants shortly after birth — the time of maximal risk for almost all other causes of non-trauma infant death.

Overview Sudden infant death syndrome is the unexplained death of a baby. The baby is usually less than a year old and seems to be healthy. It often happens during sleep. Sudden infant death syndrome also is known as SIDS . It is sometimes called crib death because infants often die in their cribs. The cause of SIDS is unknown. But it may be caused by problems in the area of an infant's brain that controls breathing and waking up from sleep. Researchers have found some things that might put babies at higher risk.

This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein.

Etiology HCHWA-D is due to a mutation in the APP gene on chromosome 21q21.2, encoding the beta-amyloid precursor protein. ... Genetic testing reveals a mutation in the APP gene. Differential diagnosis Differential diagnoses include other conditions that could cause intracerebral hemorrhage such as coagulopathies, vasculitis (see these terms), CNS neoplasms, cerebral vascular malformations, ischemic stroke and antecedent trauma.

The Dutch type is the most common, with over 200 affected individuals reported in the scientific literature. Causes Mutations in the APP gene are the most common cause of hereditary cerebral amyloid angiopathy. APP gene mutations cause the Dutch, Italian, Arctic, Iowa, Flemish, and Piedmont types of this condition. ... Familial British and Danish dementia are caused by mutations in the ITM2B gene. The APP gene provides instructions for making a protein called amyloid precursor protein. ... Additionally, the ITM2B protein may be involved in processing the amyloid precursor protein. Mutations in the APP , CST3 , or ITM2B gene lead to the production of proteins that are less stable than normal and that tend to cluster together (aggregate). ... Learn more about the genes associated with Hereditary cerebral amyloid angiopathy APP CST3 ITM2B Inheritance Pattern Hereditary cerebral amyloid angiopathy caused by mutations in the APP , CST3 , or ITM2B gene is inherited in an autosomal dominant pattern , which means one copy of the altered gene in each cell is sufficient to cause the disorder.

This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein.

This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein.

This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein.

This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein.

Inclusion body myositis (IBM) is a slowly progressive degenerative inflammatory disorder of skeletal muscles characterized by late onset weakness of specific muscles and distinctive histopathological features. Epidemiology IBM has a highly variable prevalence according to geographic, ethnic and age criteria. Prevalence in the general population ranges from 1:1,000,000 to 1:14,000 but a three-fold increase is observed when considering only a population over 50 years. Underdiagnosis may be an explanation for the high ethno-geographic variation. Male-to-female ratio is 2:1 on average (0.5 to 6.5:1). Clinical description IBM onset is over 50 years but may also occur earlier, in the 5th decade.

Inflammatory muscle disease in older adults This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed. Find sources: "Inclusion body myositis" – news · newspapers · books · scholar · JSTOR ( September 2009 ) ( Learn how and when to remove this template message ) Inclusion body myositis Other names sIBM Specialty Rheumatology Inclusion body myositis ( IBM ) ( / m aɪ oʊ ˈ s aɪ t ɪ s / ) (sometimes called sporadic inclusion body myositis , sIBM ) is the most common inflammatory muscle disease in older adults. [1] The disease is characterized by slowly progressive weakness and wasting of both proximal muscles (closest to the body's midline) and distal muscles (the limbs), most apparent in the finger flexors and knee extensors . [2] IBM is often confused with an entirely different class of diseases, called hereditary inclusion body myopathies (hIBM). [3] [4] The "M" in hIBM is an abbreviation for "myopathy" while the "M" in IBM is an abbreviation for "myositis". These diseases should not be confused with each other. In IBM, two processes appear to occur in the muscles in parallel, one autoimmune and the other degenerative. Inflammation is evident from the invasion of muscle fibers by immune cells .

Idiopathic inflammatory myopathy is a group of disorders characterized by inflammation of the muscles used for movement (skeletal muscles). Idiopathic inflammatory myopathy usually appears in adults between ages 40 and 60 or in children between ages 5 and 15, though it can occur at any age. The primary symptom of idiopathic inflammatory myopathy is muscle weakness, which develops gradually over a period of weeks to months or even years. Other symptoms include joint pain and general tiredness (fatigue). There are several forms of idiopathic inflammatory myopathy, including polymyositis, dermatomyositis, and sporadic inclusion body myositis. Polymyositis and dermatomyositis involve weakness of the muscles closest to the center of the body (proximal muscles), such as the muscles of the hips and thighs, upper arms, and neck.

Inclusion body myositis (IBM) is a progressive muscle disorder characterized by muscle inflammation, weakness, and atrophy (wasting). It is a type of inflammatory myopathy . IBM develops in adulthood, usually after age 50. The symptoms and rate of progression vary from person to person. The most common symptoms include progressive weakness of the legs, arms, fingers, and wrists. Some people also have weakness of the facial muscles (especially muscles controlling eye closure), or difficulty swallowing (dysphagia). Muscle cramping and pain are uncommon, but have been reported in some people.