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Studies suggest that prenatal care for mothers during their pregnancies can prevent congenital amputation. Knowing environmental and genetic risks is also important. Heavy exposure to chemicals, smoking, alcohol, poor diet, or engaging in any other teratogenic activities while pregnant can increase the risk of having a child born with a congenital amputation. Folic acid is a multivitamin that has been found to reduce birth defects.
Treatment of Roberts syndrome is individualized and specifically aimed at improving the quality of life for those afflicted with the disorder. Some of the possible treatments include: surgery for the cleft lip and palate, correction of limb abnormalities (also through surgery), and improvement in prehensile hand grasp development.
There is currently no treatment or cure for Waardenburg syndrome. The symptom most likely to be of practical importance is deafness, and this is treated as any other irreversible deafness would be. In marked cases there may be cosmetic issues. Other abnormalities (neurological, structural, Hirschsprung disease) associated with the syndrome are treated symptomatically.
Probably, the most well-known teratogenic drug is thalidomide. It was developed near the end of the 1950s by Chemie Grűnenthal as a sleep inducing aid and antiemetic. Because of its ability to prevent nausea it was prescribed for pregnant women in almost 50 countries worldwide between 1956–1962. Until William McBride published the study leading to its withdrawal from the market at 1961, about 8- 10 000 severely malformed children were born. The most typical disorder induced by thalidomide were reductional deformities of the long bones of the extremities. Phocomelia otherwise a rare deformity, which therefore helped to recognise the teratogenic effect of the new drug. Among other malformations caused by thalidomide were those of ears, eyes, brain, kidney, heart, digestive and respiratory tract. 40% of the prenatally affected children died soon after birth. As thalidomide is used today as a treatment for multiple myeloma and leprosy, several births of affected children were described in spite of the strictly required use of contraception among female patients treated by it.
Vitamin A, or retinol, is the sole vitamin which is embryotoxic even in a therapeutic dose, for example in multivitamins, because its metabolite, the retinoic acid, plays an important role as a signal molecule in the development of several tisues and organs. Its natural precursor, the β-carotene, is considered safe, whereas the consumption of animal liver can lead to malformation, as the liver stores lipophile vitamins, including retinol. Isotretinoin (13-cis-retinoic-acid; brand name Roaccutane), vitamine A analog, which is often used to treat severe acne, is such a strong teratogen that just a single dose taken by a pregnant woman (even transdermally) may result in serious birth defects. Because of this effect, most countries have systems in place to ensure that it is not given to pregnant women, and that the patient is aware of how important it is to prevent pregnancy during and at least one month after treatment. Medical guidelines also suggest that pregnant women should limit vitamin A intake to about 700 μg/day, as it has teratogenic potential when consumed in excess. Vitamine A and similar substances can induce spontaneous abortions, premature births, defects of eyes (microphthalmia), ears, thymus, face deformities, neurological (hydrocephalus, microcephalia) and cardiovascular defects, as well as mental retardation.
Tetracycline, an antibiotic, should never be prescribed to women in the reproductive age or children, because of its negative impact on bone mineralization and teeth mineralization. The "tetracycline teeth" have brown or grey colour as a result of a defective development of both the dentine and the enamel of teeth.
Several anticonvulsants are known to be highly teratogenic. Phenytoin, also known as diphenylhydantoin, along with carbamazepine is responsible for the fetal hydantoin syndrome, which may typically include broad nose base, cleft lip and/or palate, microcephalia, nails and fingers hypoplasia, intrauterine growth restriction and mental retardation. Trimethadione taken during pregnancy is responsible for the fetal trimethadione syndrome, characterized by craniofacial, cardiovascular, renal and spine malformations, along with a delay in mental and physical development. Valproate has anti-folate effects, leading to neural tube closure-related defects such as spina bifida. Lower IQ and autism have recently also been reported as a result of intrauterine valproate exposure.
Hormonal contraception is considered as harmless for the embryo. Peterka and Novotná do however state that syntethic progestines used to prevent miscarriage in the past frequently caused masculinization of the outer reproductive organs of female newborns due to their androgenic activity. Diethylstilbestrol is a synthetic estrogen used from the 1940s to 1971 when the prenatal exposition has been linked to the clear-cell adenocarcinoma of the vagina. Following studies showed elevated risks for other tumors and congenital malformations of the sex organs for both sexes.
All cytostatics are strong teratogens, abortion is usually recommended when pregnancy is found during or before chemotherapy. Aminopterin, a cytostatic drug with anti-folate effect, was used during the 1950s and 1960s to induce therapeutic abortions. In some cases the abortion didn´t happen, but the newborns suffered a fetal aminopterin syndrome consisting of growth retardation, craniosynostosis, hydrocephalus, facial dismorphities, mental retardation and/or leg defomities
For most cases the diagnosis for congenital amputation is not made until the infant is born. One procedure that is helpful in determining this condition in an infant is an ultrasound examination of a fetus when still in the mother's abdomen as it can reveal the absence of a limb. However, since ultrasounds are routine they may not pick up all the signs of some of the more subtle birth defects.
The most popular method of treatment for congenital amputation is having the child be fit for a prosthesis which can lead to normal development, so the muscles don't atrophy. If there is congenital amputation of the fingers, plastic surgery can be performed by using the big toe or second toes in place of the missing fingers of the hand.
In rare cases of amniotic banding syndrome, if diagnosed "in utero", fetal surgery may be considered to save a limb which is in danger of amputation.
The complete absence of an arm or leg in amelia occurs as a result of the limb formation process being either prevented or interrupted very early in the developing embryo: between 24 and 36 days following fertilization. Tetra-amelia syndrome appears to have an autosomal recessive pattern of inheritance - that is, the parents of an individual with tetra-amelia syndrome each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. In a few cases, amelia may be attributed to health complications during the early stages of pregnancy, including infection, failed abortion or complications associated with removal of an IUD after pregnancy, or use of teratogenic drugs, such as thalidomide.
Substances whose toxicity can cause congenital disorders are called "teratogens", and include certain pharmaceutical and recreational drugs in pregnancy as well as many environmental toxins in pregnancy.
A review published in 2010 identified 6 main teratogenic mechanisms associated with medication use: folate antagonism, neural crest cell disruption, endocrine disruption, oxidative stress, vascular disruption and specific receptor- or enzyme-mediated teratogenesis.
It is estimated that 10% of all birth defects are caused by prenatal exposure to a teratogenic agent. These exposures include, but are not limited to, medication or drug exposures, maternal infections and diseases, and environmental and occupational exposures. Paternal smoking use has also been linked to an increased risk of birth defects and childhood cancer for the offspring, where the paternal germline undergoes oxidative damage due to cigarette use. Teratogen-caused birth defects are potentially preventable. Studies have shown that nearly 50% of pregnant women have been exposed to at least one medication during gestation. During pregnancy, a female can also be exposed to teratogens from the contaminated clothing or toxins within the seminal fluid of a partner. An additional study found that of 200 individuals referred for genetic counseling for a teratogenic exposure, 52% were exposed to more than one potential teratogen.
Ectromelia is a congenital condition where long bones are missing or underdeveloped.
Examples include:
- Amelia
- Hemimelia
- Phocomelia
- Sirenomelia
The diagnosis of tetra-amelia syndrome is established clinically and can be made on routine prenatal ultrasonography. WNT3 is the only gene known to be associated with tetra-amelia syndrome. Molecular genetic testing on a clinical basis can be used to diagnose the incidence of the syndrome. The mutation detection frequency is unknown as only a limited number of families have been studied. Affected infants are often stillborn or die shortly after birth.
Turning the baby, technically known as external cephalic version (ECV), is when the baby is turned by gently pressing the mother’s abdomen to push the baby from a bottom first position, to a head first position. ECV does not always work, but it does improve the mother’s chances of giving birth to her baby vaginally and avoiding a cesarean section. The World Health Organisation recommends that women should have a planned cesarean section only if an ECV has been tried and did not work.
Women who have an ECV when they are 36–40 weeks pregnant are more likely to have a vaginal delivery and less likely to have a cesarean section than those who do not have an ECV. Turning the baby before this time makes a head first birth more likely but ECV before the due date can increase the risk of early or premature birth which can cause problems to the baby.
There are treatments that can be used which might affect the success of an ECV. Drugs called beta-stimulant tocolytics help the woman’s muscles to relax so that the pressure during the ECV does not have to be so great. Giving the woman these drugs before the ECV improves the chances of her having a vaginal delivery because the baby is more likely to turn and stay head down. Other treatments such as using sound, pain relief drugs such as epidural, increasing the fluid around the baby and increasing the amount of fluids to the woman before the ECV could all effect its success but there is not enough research to make this clear.
Turning techniques mothers can do at home are referred to Spontaneous Cephalic Version (SCV), this is when the baby can turn without any medical assistance. Some of these techniques include; a knee to chest position, the breech tilt and moxibustion, these can be performed after the mother is 34 weeks pregnant. Although there is not a lot of evidence to support how well these techniques work, it has worked for some mothers.
Tetra-amelia syndrome ("" + "amelia"), also called autosomal recessive tetraamelia, is an extremely rare autosomal recessive congenital disorder characterized by the absence of all four limbs. Other areas of the body are also affected by malformations, such as the face, skull, reproductive organs, anus and pelvis. The disorder is caused by mutations in the WNT3 gene.
Dysmelia can be caused by
- inheritance of abnormal genes, e.g. polydactyly, ectrodactyly or brachydactyly, symptoms of deformed limbs then often occur in combination with other symptoms (syndromes)
- external causes during pregnancy (thus not inherited), e.g. via amniotic band syndrome
- teratogenic drugs (e.g. thalidomide, which causes phocomelia) or environmental chemicals
- ionizing radiation (nuclear weapons, radioiodine, radiation therapy)
- infections
- metabolic imbalance
Dysmelia (from Gr. δυσ- "dys", "bad" + μέλ|ος "mél|os", "limb" + Eng. suff. -ia) is a congenital disorder of a limb resulting from a disturbance in embryonic development.
Tetra-amelia syndrome is characterized by the complete absence of all four limbs. The syndrome causes severe malformations of various parts of the body, including the face and head, heart, nervous system, skeleton, and genitalia. In many cases, the lungs are underdeveloped, which makes breathing difficult or impossible. Because children with tetra-amelia syndrome have such serious medical problems, most are stillborn or die shortly after birth.
When a baby is born bottom first there is more risk that the birth will not be straight forward and that the baby could be harmed. For example, when the baby's head passes through the mother’s pelvis the umbilical cord can be compressed which prevents delivery of oxygenated blood to the baby. Due to this and other risks, babies in breech position are usually born by a planned caesarean section in developed countries.
Caesarean section reduces the risk of harm or death for the baby but does increase risk of harm to the mother compared with a vaginal delivery. It is best if the baby is in a head down position so that they can be born vaginally with less risk of harm to both mother and baby. The next section is looking at External cephalic version or ECV which is a method that can help the baby turn from a breech position to a head down position.
Vaginal birth of a breech baby has its risks but caesarean sections are not always available or possible, a mother might arrive in hospital at a late stage of her labour or may choose not to have a caesarean section. In these cases, it is important that the clinical skills needed to deliver breech babies are not lost so that mothers and babies are as safe as possible. Compared with developed countries, planned caesarean sections have not produced as good results in developing countries - it is suggested that this is due to more breech vaginal deliveries being performed by experienced, skilled practitioners in these settings.
Yim–Ebbin syndrome is a congenital disorder characterized by the absence of arms, a cleft lip and palate, hydrocephalus, and an iris coloboma. It was first described by Yim and Ebbin in 1982, and later by Thomas and Donnai in 1994. In 1996, a third case was reported by Froster et al. who suggested that the three cases were related and represented a distinct syndrome. In 2000, a similar case was reported by Pierri et al.
It is also known as "amelia cleft lip palate hydrocephalus iris coloboma".
Roberts syndrome, or sometimes called "pseudothalidomide syndrome", is an extremely rare genetic disorder that is characterized by mild to severe prenatal retardation or disruption of cell division, leading to malformation of the bones in the skull, face, arms, and legs.
Roberts syndrome is also known by many other names, including: hypomelia-hypotrichosis-facial hemangioma syndrome, SC syndrome (once thought to be an entirely separate disease), pseudothalidomide syndrome, Roberts-SC phocomelia syndrome, SC phocomelia syndrome, Appelt-Gerken-Lenz syndrome, RBS, SC pseudothalidomide syndrome, and tetraphocomelia-cleft palate syndrome. It is a genetic disorder caused by the mutation of the ESCO2 gene on 8th chromosome. Named after the famous Philadelphia surgeon and physician, Dr. John Bingham Roberts (1852–1924), who first described the syndrome in 1919, it is one of the rarest autosomal recessive disorders, affecting approximately 150 known individuals.
The syndrome is both autosomal, in that there are equal numbers of copies of the gene in both males and females, and recessive, meaning the child must inherit the defective gene from both parents. The mutation causes cell division to occur slowly or unevenly, and the cells with abnormal genetic content die. Roberts syndrome can affect both males and females. Although the disorder is rare, the affected group is diverse. The mortality rate is high in severely affected individuals.
Waardenburg syndrome is a rare genetic disorder most often characterized by varying degrees of deafness, minor defects in structures arising from the neural crest, and pigmentation changes. It was first described in 1951. The syndrome was later found to have four types. For example, type II was identified in 1971, to describe cases where dystopia canthorum was not present. Some types are now split into subtypes, based upon the gene responsible for the condition.
Depending on the severity, treatment involves either oral or intravenous antibiotics, using penicillins, clindamycin, or erythromycin. While illness symptoms resolve in a day or two, the skin may take weeks to return to normal.
Because of the risk of reinfection, prophylactic antibiotics are sometimes used after resolution of the initial condition. However, this approach does not always stop reinfection.
The disease prognosis includes:
- Spread of infection to other areas of body can occur through the bloodstream (bacteremia), including septic arthritis. Glomerulonephritis can follow an episode of streptococcal erysipelas or other skin infection, but not rheumatic fever.
- of infection: Erysipelas can recur in 18–30% of cases even after antibiotic treatment. A chronic state of recurrent erysipelas infections can occur with several predisposing factors including alcoholism, diabetes, and tinea pedis (athlete's foot). Another predisposing factor is chronic cutaneous edema, such as can in turn be caused by venous insufficiency or heart failure.
- Lymphatic damage
- Necrotizing fasciitis, commonly known as "flesh-eating" bacterial infection, is a potentially deadly exacerbation of the infection if it spreads to deeper tissue.