Osteogenesis Imperfecta Bone Essay
Osteogenesis Imperfecta or more commonly known as Brittle Bone Disease, is a
condition causing extremely fragile bones and is known to be a congenital disease. This means
you are born with it. It is caused by a defect in the gene that produces type I collagen which is an
important building block of bone. Most causes of Osteogenesis Imperfecta are inherited from a
parent caring the gene . Some cases are the result of new genetic mutations. People with
Osteogenesis Imperfecta are usually below average hight. Osteogenesis Imperfecta does not
seem to occur in any certain race, it effects all races male and or female. Osteogenesis Imperfecta Bone Essay. A person with
ORDER A PLAGIARISM-FREE PAPER NOW
Osteogenesis Imperfecta has a 50 per cent chance of passing on the gene and the disease to there
offspring.
The symptoms of Osteogenesis Imperfecta are as follows:
Type I which accounts for 60 per cent of all cases
Type II
Type III
Type IV
The diagnoses of Osteogenesis Imperfecta.
Osteogenesis Imperfecta is diagnosed a few different ways. In most cases the diagnosis is
made from the pattern of fractures. In severely affected people X-rays may show characteristics
abnormalities. In the USA two specialized tests are sometimes used for the diagnosis of
Osteogenesis Imperfecta. One involves taking a small piece of the skin, culturing the cells and
chemically examining the collagen produced. The other uses a blood sample and searches for
mutations of the genes coding for the collagen of bone. Neither tests are more than 85 per cent
accurate in identifying cases of Osteogenesis Imperfecta. Chronic Villus Sampling maybe done
during pregnancy to determine if the fetus has the condition. However, because so many different. Osteogenesis Imperfecta Bone Essay.
mutations can cause Osteogenesis Imperfecta, some forms can not be diagnosed with a genetic
test. Often the severe form Type II can be detected on an ultra sound when the fetus is as young
as sixteen weeks old.
The treatment of Osteogenesis Imperfecta.
There is no cure yet for this disease however curtain therapies can reduce pain and complications
due to this disease. Bisphosphonates are drugs that have been used to treat Osteoporosis. They
can increase the strength and the hardness of bone in people with Osteogenesis Imperfecta . They
have also been shown to highly reduce fracture rate. Swimming and low impact exercises help
maintain the strength of the bones. In more severe causes surgery may be used to place metal
rods into long bone in the leg to help reduce the risk of any further fractures.
Osteogenesis imperfecta (OI) is a group of rare inherited disorders of connective tissue with the common feature of excessive fragility of bones caused by mutations in collagen. Diagnosis is mainly based on the clinical features of the disorder. We report, the case of a male neonate delivered to a 33-year-old para 2 female at University of Nigeria Teaching Hospital, Enugu with no family history suggestive of OI. He had clinical features of a type II OI and severe birth asphyxia. Multidisciplinary management was instituted, but he died on the 7th day of life. Osteogenesis Imperfecta Bone Essay..
Osteogenesis imperfecta (OI) is a group of rare inherited disorders of connective tissue with the common feature of excessive fragility of bones.[1] It is caused by mutations in the collagen, type I, alpha 1 and collagen type I alpha 2 genes, which encode the alpha 1 and the alpha 2 chain of type I procollagen, respectively.[2] Molecular genetic studies have detected more than 150 mutations of these genes.[2] Other mutations have been identified in the leucine proline-enriched proteoglycan 1, cartilage associated protein and peptidyl-proly lisomerase B genes.[3,4]
The incidence is 1:20,000 and occurs in all races and ethnicity.[5] It is mostly inherited as an autosomal dominant disorder, but autosomal recessive forms have been reported.[6,7] The clinical classification by Sillence et al., is the most helpful in prognosis and genetic counseling and it groups OI into four types: Type I OI is mild, type II is perinatal lethal, type III is progressive deforming and type IV is moderately severe.[8] It is characterized by multiple and recurrent fractures, which are intrauterine or perinatal or post-natal. Other features include blue sclera, otosclerosis with hearing loss, high arched palate, hyperlaxity of ligaments and skin, “dentinogenesis imperfecta” (defective dentition), scoliosis and growth retardation. Wormian bones could also be seen on skull X-ray. Intelligence is not affected.[3]
Diagnosis can be made clinically. Radiographic support and confirmation by collagen analysis of skin fibroblast culture or blood deoxyribonucleic acid analysis may be necessary in some cases.[5,9] This is important for genetic counseling and cases of suspected child abuse. Prenatal diagnosis for at risk pregnancies by fetal ultrasonography in the early 2nd trimester is possible and enables care.[5,10] There’s no cure for OI.Osteogenesis Imperfecta Bone Essay.. Management is multidisciplinary involving mainly surgery, physiotherapy and rehabilitation. However, medical treatment, especially with bisphosphonate have shown good prospects.[3,5,9]
This case is being reported because of its rarity, especially among blacks and also, to review the literature to highlight the challenges and advances in its management.
O.E [Figure 1] was a male neonate delivered to a 33-year-old para 2 female at University of Nigeria Teaching Hospital, Enugu. He was admitted to the new born special care unit (NBSCU) 10 min after birth for inability to cry at birth, multiple deformities with abnormal body posture.
His mother received routine antenatal care and pregnancy was uneventful. Only routine drugs were used during pregnancy. Prenatal ultrasonography detected no fractures or other abnormalities. Onset of labor was spontaneous and lasted about 8 h with spontaneous vertex delivery. Apgar score was four at 10 min. There was no history of the tendency to fractures in the family and no family history of any baby with fracture at birth.
On examination in the NBSCU, he was found to be in “frog like position” with abnormal movement of the left thigh. He was in respiratory distress with acrocyanosis. He had blue-grey sclera and micrognathia with a high arched palate. Musculoskeletal system examination revealed pectus excavatum, fixed flexion deformity of the fingers, crepitus of the right humerus and ulnar and both femurs with bilateral talipes equinovarus and micromelia.
A diagnosis of severe birth asphyxia in a neonate with OI type II was made. Radiograph revealed fractures of the right humerus, ulna and femur with osteopenia. Treatment was mainly supportive with minimal handling, intermittent suctioning and intra-nasal oxygen administration. The parents were counseled and the baby was also reviewed by the orthopaedic surgeons and anesthetist for later surgical intervention when he stabilized. However, he continued to deteriorate until his death on the 7th day of life. Osteogenesis Imperfecta Bone Essay..
OI is a rare disorder. It has variously been called “osteopsathyrosis idiopathica” by Lobstein, “fragilitus osseum”, hereditary fragility of bone, later brittle bone disease and fragile bone disease, but the current name “OI” was coined by Vrolik in 1845.[11,12] The disorder was first brought to the limelight by the Swede, Olof Jakob Ekman in his doctorate thesis at Uppsala in 1788 as “osteomalacia congenital” involving three generations.[12,13] Since then, various researchers have tried to describe and classify this disorder into various types: In 1906, Looser, proposed the classification: “Congenita” and “tarda” based on time of fractures.[14] Congenita type has fracture in-utero and most were either still birth or died soon after. OI congenita was found in children whose parents have no traces of the disease while OI tarda was the hereditary form. In 1975, Bauze et al.,[15] describing the clinical, radiological and biochemical features of 42 patients classified OI into three: mild, moderate and severe based on deformity of one or more of the long bones. Mild had no long bone deformity; moderate had minor long bone deformities while severe had severe long bone deformities. One of their arguments is that long bone deformity is a strong prognostic feature and easily recognizable.
The most widely acceptable classification was by Sillence et al.,[8] in 1979, in which they grouped the disorder into four: Type I; dominantly inherited OI with blue sclera, type II; perinatally lethally deforming OI with crumpled femora, type III; progressively deforming OI with normal sclera and type IV; dominantly inherited OI with normal sclerae. Type I is a mild form with recurrent fractures and blue sclera. It has A and B subtypes depending on the absence or presence of dentinogenesis imperfecta. Fractures are less common after puberty. Osteogenesis Imperfecta Bone Essay.. Type II is autosomal recessive and generally lethal in the newborn period with multiple congenital fractures, micromelia and severe lung disease. Types III and IV represent intermediate phenotypes with type III being the most severe non-lethal form causing significant bony deformity secondary to multiple fractures, which can be congenital. Type IV also has subtypes A and B based on the presence of dentinogenesis imperfecta.
Over the past few decades, five additional types (V-IX) have been identified using histological and molecular findings.[6,7] Plotkin[16] proposed a classification of OI as syndromes secondary to mutations in type I pro-collagen genes and “syndromes resembling osteogenesis imperfecta” as those secondary to mutations other than the type I pro-collagen genes.
ORDER A PLAGIARISM-FREE PAPER NOW
The diagnosis of OI type II in our patient was based on the clinical features of multiple fractures at birth, blue-grey sclera, micromelia and radiological evidence of osteopenia. Although, there was no positive family history suggestive of OI or other skeletal malformations, it was noted that sporadic cases were most likely in type II.[8] Akiode et al., in Sagamu,[17] and Akinola et al., in Lagos,[18] both in Western Nigeria reported a single and two cases respectively of female babies based on the clinical findings of multiple fractures, blue sclera and craniotabes at birth with radiological evidence of defective ossification of the skull. Osteogenesis Imperfecta Bone Essay..
Although, reports available,[5,19] show no racial or ethnic variation, the sparseness of reports from Africa and obvious absence of blacks in most of the case reports from other continents may be an indication of low incidence in Africans. It may also be as a result of under reporting due to wide unavailability of facilities for disease confirmation. Although, an autosomal recessive form of type III, which is very rare, has been reported as been relatively more common among South African black population,[20] the etiology is not certain as type I collagen structural genes Colia one and two have not been demonstrated to be mutated in the affected population.[21] There have also been reports of OI in twins from Burundi[22] and more recently Nigeria.[23]
Prenatal diagnosis by fetal ultrasonography is possible,[5] but no abnormality was detected in our patient prenatally. Likewise, in the first case earlier reported within the country. The other case, report did not state the ultrasonography findings. It’s also possible that the fractures occurred during delivery in both cases since prenatal diagnosis is mainly based on the presence of fractures. Fractures can occur even on minimal stress, but there is no empiric data to prove that caesarean section will improve outcome over vaginal birth even when diagnosed prenatally.[24] However, its poor prognostic course raises an ethical question of termination of pregnancy on detection. Despite this, advances in technology continue to proffer options for these children. Osteogenesis Imperfecta Bone Essay.