primary autosomal recessive microcephaly 3

Primary autosomal recessive microcephaly 3 (MCPH3) is a rare genetic disorder characterized by significantly reduced head circumference, brain weight, and cerebral cortex size [1]. This condition is caused by homozygous or compound heterozygous mutation in the CDK5RAP2 gene [4].

The symptoms of MCPH3 include:

• Significantly reduced head circumference
• Reduced brain weight and cerebral cortex size
• Intellectual disability and developmental delays are common in many affected individuals [5]

MCPH3 is a prototype of isolated primary (congenital) microcephaly, affecting predominantly the cerebral cortex [9]. It is essential to note that MCPH3 is an autosomal recessive disorder, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to express the condition.

References: [1] Apr 1, 2011 — The reduced brain size underlies the small head size, intellectual disability, and developmental delays seen in many affected individuals. Learn ... [4] A number sign (#) is used with this entry because primary microcephaly-3 (MCPH3) is caused by homozygous or compound heterozygous mutation in the CDK5RAP2 ... [5] Apr 1, 2011 — The reduced brain size underlies the small head size, intellectual disability, and developmental delays seen in many affected individuals. Learn ... [9] by S Z

Based on the provided context, here are the signs and symptoms of primary autosomal recessive microcephaly 3 (MCPH3):

• Delayed speech and language skills [4][5]
• Motor skills, such as sitting, standing, and walking, may be mildly delayed [3][5]
• Failure to thrive in infancy [5]
• Abnormality of body height [5]
• Decreased body weight [5]

Additionally, individuals with MCPH3 may also experience:

• Intellectual disability [2][6]
• Poor motor function [6]
• Seizures (present in 10% of cases) [1]

It's worth noting that the severity and presentation of these symptoms can vary among affected individuals.

Based on the available information, here are some diagnostic tests for primary autosomal recessive microcephaly:

• Molecular genetic testing: This is a type of test that can identify mutations in several genes associated with autosomal recessive microcephaly. [6]
• Exome Sequencing with CNV Detection: This is a comprehensive genetic test that can detect mutations and copy number variations (CNVs) in the genome, including those associated with primary autosomal recessive microcephaly. [3]
• Prenatal ultrasound: This imaging test can diagnose microcephaly during pregnancy, but it's essential to note that the absence of microcephaly on prenatal ultrasound does not exclude the condition. [4]

Additionally, there are other tests mentioned in the context, such as:

• Head circumference measurement: Measuring the distance around the widest part of the head can help diagnose microcephaly. [2]
• Electroencephalogram (EEG) and brain magnetic resonance imaging (MRI): These neuroimaging tests can be performed to evaluate the brain's electrical activity and structure, respectively. [8]

It's worth noting that a diagnosis of primary autosomal recessive microcephaly is typically made based on a combination of clinical evaluation, genetic testing, and other diagnostic tests.

References: [2] - Context 2 [3] - Context 3 [4] - Context 4 [6] - Context 6

Treatment Options for Primary Autosomal Recessive Microcephaly

Primary autosomal recessive microcephaly (MCPH) is a rare genetic disorder that affects brain development, leading to reduced head size. While there is no specific etiologic treatment for MCPH, various treatments can help manage associated symptoms.

• Seizure Management: Seizures are usually stabilized with common anticonvulsants [5].
• Ritalin Therapy: Ritalin may be helpful in managing hyperkinesia (excessive movement) [4].
• Physical and Speech Therapy: These therapies can be beneficial in improving motor skills and communication abilities [3].

It's essential to note that treatment for MCPH is symptomatic, meaning it focuses on alleviating symptoms rather than addressing the underlying cause. A multidisciplinary team, often including a pediatric neurologist and developmental pediatrician, speech-language pathologist, and other specialists, can provide comprehensive care for individuals with MCPH [2].

References: [1] Context result 7 [2] Context result 2 [3] Context result 3 [4] Context result 5 [5] Context result 5

Differential Diagnosis of Primary Autosomal Recessive Microcephaly

Primary autosomal recessive microcephaly (MCPH) is a rare disorder characterized by reduced head circumference at birth, with no major brain abnormalities. However, it can be challenging to diagnose MCPH as it may present with similar symptoms to other conditions. Here are some differential diagnoses that should be considered:

• Seckel syndrome: This is a rare genetic disorder that presents with microcephaly, intellectual disability, and characteristic facial features.
• Microcephalic primordial dwarfism: This is a group of disorders characterized by severe microcephaly, short stature, and other physical abnormalities.
• Congenital infections: Certain congenital infections, such as toxoplasmosis or rubella, can cause microcephaly and other neurological symptoms.
• Metabolic disorders: Some metabolic disorders, such as phenylketonuria (PKU), can present with microcephaly and intellectual disability.

Key Points to Consider

• Microcephaly may indicate a significant underlying congenital, genetic, or metabolic condition; or acquired disease such as a congenital infection [7].
• Neuroimaging of the brain with ultrasound and/or MRI are useful for the differential diagnosis in patients with primary microcephaly [5].

References

[3] Delayed motor development, mild-to-severe intellectual disability (ID), behavior problems, and other neurological symptoms can be associated with central nervous system involvement in MCPH. [5] Neuroimaging of the brain with ultrasound and/or MRI are useful for the differential diagnosis in patients with primary microcephaly. [7] Microcephaly may indicate a significant underlying congenital, genetic, or metabolic condition; or acquired disease such as a congenital infection.