Anencephaly
Disease Details
Family Health Simplified
- Description
- Anencephaly is a severe congenital condition where a major portion of the brain, skull, and scalp fails to develop.
- Type
- Anencephaly is a type of neural tube defect. It typically occurs sporadically, meaning it generally arises due to non-hereditary factors, but it can also be influenced by a combination of genetic and environmental factors. The exact pattern of genetic transmission is not well established, but it can occur more frequently in families with a history of neural tube defects, suggesting some genetic predisposition.
- Signs And Symptoms
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### Anencephaly: Signs and Symptoms
Anencephaly is a serious congenital condition where a major portion of the brain, skull, and scalp fails to develop properly. Due to this severe neural tube defect, the condition is characterized by the following signs and symptoms:
1. **Absence of a Major Portion of the Brain and Skull:**
- Missing or underdeveloped forebrain (cerebrum).
- Improper skull development, often leading to exposure of the remaining brain tissue.
2. **Facial and Cranial Abnormalities:**
- Prominent facial bones due to the lack of skull formation.
- Abnormally shaped head or face.
3. **Neurological Impairments:**
- Lack of consciousness and inability to perceive pain.
- Reflex actions may be present but without cognitive function.
4. **Absence of Functioning Cerebral Tissue:**
- No sensory or cognitive responses.
- Impaired regulation of critical bodily functions (e.g., breathing, heart rate).
5. **Hydrocephalus:**
- Accumulation of cerebrospinal fluid in the brain, leading to increased head size in some cases.
Anencephaly is usually diagnosed during pregnancy through ultrasound and other imaging studies. The condition is not compatible with prolonged life, often leading to stillbirth or death shortly after birth. - Prognosis
- Anencephaly is a severe congenital condition where a major portion of the brain, skull, and scalp is absent. The prognosis for individuals with anencephaly is extremely poor. Infants affected by this condition are typically stillborn or die shortly after birth. Survival beyond a few days is rare and usually involves extensive medical support.
- Onset
- Anencephaly is a serious birth defect that is present at birth (congenital). It occurs when a major portion of the brain, skull, and scalp fails to develop during embryonic growth, typically within the first month of pregnancy.
- Prevalence
- The prevalence of anencephaly varies by geographic location and population. In the United States, it is estimated to occur in about 3 out of every 10,000 pregnancies. However, rates can be higher or lower in different regions.
- Epidemiology
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Anencephaly is a severe congenital condition characterized by the absence of a major portion of the brain, skull, and scalp.
**Epidemiology:**
- **Incidence:** Anencephaly occurs in approximately 1 in 1,000 to 1 in 10,000 live births worldwide, though rates can vary significantly by region and population.
- **Risk Factors:** The exact cause is not well understood, but genetic, environmental, and nutritional factors play a role. A significant risk factor is a deficiency in folic acid (vitamin B9) during early pregnancy.
- **Demographics:** It affects more females than males and tends to be more prevalent in certain populations, including certain ethnic groups and geographic regions.
Nanotechnology applications in anencephaly are currently limited, but ongoing research may potentially explore avenues for early diagnosis and better understanding of the condition's developmental biology. - Intractability
- Yes, anencephaly is considered intractable. It is a severe congenital condition characterized by the absence of a major portion of the brain, skull, and scalp. Anencephaly is generally incompatible with life, as most affected infants are stillborn or die shortly after birth. There is currently no effective treatment or cure for this condition.
- Disease Severity
- Anencephaly is a severe congenital condition where a significant portion of the brain, skull, and scalp is absent. It is typically diagnosed prenatally and is incompatible with long-term survival. Most affected infants are stillborn or die within hours or days after birth. Disease severity is extremely high. "nan" typically stands for "not a number" and isn't applicable to this context.
- Healthcare Professionals
- Disease Ontology ID - DOID:0060668
- Pathophysiology
- Anencephaly is a severe congenital condition characterized by the absence of a major portion of the brain, skull, and scalp. It results from a neural tube defect occurring during embryonic development, typically between the 23rd and 26th day following conception. The neural tube fails to close properly, leading to the absence or underdevelopment of major parts of the brain and skull. This condition is incompatible with prolonged life, and affected infants are usually stillborn or die shortly after birth.
- Carrier Status
- Carrier status typically refers to whether an individual carries a gene mutation that might be passed on to offspring, often without showing symptoms themselves. Anencephaly is a neural tube defect and is usually not caused by a single gene mutation. Most cases are sporadic, but potential contributing factors include genetic variations, environmental influences, and maternal health conditions. Therefore, there isn't a specific "carrier status" for anencephaly.
- Mechanism
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Anencephaly is a severe congenital condition characterized by the absence of a major portion of the brain, skull, and scalp. It results from the failure of the upper part of the neural tube to close during fetal development, typically occurring around the 23rd to 26th day of pregnancy.
**Mechanism:**
The primary mechanism involves the failure of neural tube closure. The neural tube is the precursor to the central nervous system, which includes the brain and spinal cord. When the neural tube fails to close properly at the cranial (head) end, it results in anencephaly.
**Molecular Mechanisms:**
Several molecular mechanisms and genetic factors are implicated in anencephaly:
1. **Folic Acid Metabolism:**
- Abnormalities in folate metabolism are strongly associated with neural tube defects (NTDs), including anencephaly.
- Genes such as MTHFR (Methylenetetrahydrofolate reductase) play a role in folate metabolism. Variants in these genes can affect folate levels, which are crucial for DNA synthesis and repair during early neural development.
2. **Genetic Factors:**
- Mutations or variations in genes involved in neural tube formation and closure (e.g., VANGL, CELSR, and SCRIB) can result in anencephaly.
- Genetic syndromes such as Meckel-Gruber syndrome, which is associated with defects in genes like TMEM67, can present with anencephaly as one of the features.
3. **Signaling Pathways:**
- Disruption in critical signaling pathways like the Wnt/β-catenin pathway can impede neural tube closure. This pathway is involved in cell adhesion and migration during early embryogenesis.
- The Sonic Hedgehog (SHH) signaling pathway, which governs the growth and patterning of various tissues during development, may also play a role.
4. **Environmental Factors:**
- Teratogenic environmental factors, such as maternal diabetes, certain medications, and exposure to high temperatures during early pregnancy, can increase the risk of anencephaly through complex interactions with genetic susceptibility.
Understanding the precise molecular mechanisms underlying anencephaly requires further research, as the condition likely results from a combination of genetic predispositions and environmental influences. - Treatment
- Anencephaly is a serious birth defect in which a baby is born without parts of the brain and skull. Unfortunately, there is no treatment or cure for anencephaly. Most affected babies are stillborn, and those who are born alive typically die within hours or days. Management focuses on supportive care and comfort for the infant and providing emotional support for the family.
- Compassionate Use Treatment
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Anencephaly is a severe neural tube defect where a major portion of the brain, skull, and scalp is missing. Unfortunately, there are no effective treatments or cures for anencephaly. Most infants with this condition are either stillborn or die shortly after birth.
1. **Compassionate Use Treatment**: This involves providing experimental treatments to patients under certain circumstances when no approved therapeutic options are available. However, for anencephaly, there are no current compassionate use treatments that show efficacy in prolonging life or improving outcomes, given the extensive nature of the malformations.
2. **Off-label or Experimental Treatments**: As of now, there are no recognized off-label or experimental treatments that can reverse or significantly alter the course of anencephaly. Research is largely focused on prevention, particularly the importance of folic acid supplementation before and during early pregnancy to reduce the risk of neural tube defects.
In summary, the focus remains on prevention and supportive care, rather than treatment, due to the profound and typically fatal nature of anencephaly. - Lifestyle Recommendations
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Anencephaly is a serious birth defect in which a baby is born without parts of the brain and skull. Unfortunately, lifestyle recommendations for managing anencephaly are not applicable, as the condition is often fatal shortly after birth. Preventive measures include:
1. **Folic Acid Intake**: Women of childbearing age should consume 400 micrograms of folic acid daily before conception and during early pregnancy to reduce the risk of neural tube defects.
2. **Healthy Diet**: A balanced diet rich in vitamins and minerals can support overall maternal health.
3. **Prenatal Care**: Regular check-ups can help monitor the health of the pregnancy and manage any potential complications.
For families affected by anencephaly, counseling and support services may be beneficial for coping and decision-making. - Medication
- Anencephaly is a serious birth defect in which a baby is born without parts of the brain and skull. Unfortunately, there is no medication to treat or cure anencephaly. The condition is usually diagnosed during pregnancy through ultrasound, and management generally focuses on supportive care. Prenatal vitamins containing folic acid can help reduce the risk of neural tube defects like anencephaly in future pregnancies.
- Repurposable Drugs
- Anencephaly is a severe congenital disorder characterized by the absence of a major portion of the brain, skull, and scalp. It is a type of neural tube defect occurring early in embryonic development. Unfortunately, as of now, there are no repurposable drugs known to effectively treat or cure anencephaly. The condition is generally considered incompatible with life, and management typically focuses on supportive care and palliative measures. Research in the field continues, but no pharmacological solutions are currently available.
- Metabolites
- Anencephaly is a severe neural tube defect where there is a significant absence of portions of the brain, skull, and scalp. Because it primarily involves developmental malformations, specific metabolites directly associated with anencephaly are not well-defined. However, abnormalities in maternal metabolites, such as low levels of folic acid (vitamin B9), are associated with an increased risk of neural tube defects, including anencephaly. Elevated maternal serum alpha-fetoprotein (AFP) levels can be indicative of neural tube defects in general but are not specific metabolites for anencephaly itself.
- Nutraceuticals
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Anencephaly is a severe congenital condition where a major portion of the brain, skull, and scalp fails to develop properly. Nutraceuticals and nanotechnology (nan) are areas of growing interest in medical research, but they currently have limited applications in the management or prevention of anencephaly.
Nutraceuticals:
- Folic acid (a form of Vitamin B9): It is the most significant nutraceutical linked to the prevention of neural tube defects, including anencephaly. Adequate intake of folic acid before conception and during early pregnancy has been shown to reduce the risk of neural tube defects.
Nanotechnology (nan):
- While nanotechnology holds promise for various medical applications, there are no established nanotechnology-based treatments or preventive measures specifically for anencephaly at present. Research is ongoing, and future advances may offer new insights or interventions.
It's essential for women planning pregnancy or of childbearing age to take folic acid supplements as recommended by healthcare providers to reduce the risk of neural tube defects, including anencephaly. - Peptides
- Anencephaly is a serious birth defect in which a baby is born without parts of the brain and skull. It occurs during the early stages of pregnancy. There is no known direct link between anencephaly and peptides. While peptides are short chains of amino acids that can play various roles in biological functions, they are not currently utilized in the diagnosis, prevention, or treatment of anencephaly.