occipital horn syndrome

Occipital Horn Syndrome (OHS) Description

Occipital horn syndrome, also known as X-linked cutis laxa or Ehlers Danlos type IX, is a rare congenital disorder [1]. It is characterized by abnormalities in connective tissue, which affects various parts of the body.

Key Features:

• Connective Tissue Abnormalities: OHS is primarily marked by defects in connective tissue, leading to issues such as:
  • Skin laxity (loose skin) and hyperextensible joints [7]
  • Urinary tract diverticuli and bladder problems [6]
  • Hernias and other soft tissue abnormalities [6]
• Cranial Base Lesions: Males with OHS often have protuberant dysostotic lesions at the insertion of the occipital bone, which is a distinctive feature of the condition [3]
• Intelligence and Physical Characteristics: Individuals with OHS may experience normal or slightly delayed intelligence, along with physical characteristics such as:
  • Long neck
  • High arched palate
  • Long face
  • High forehead
  • Looseness of skin and "double jointed" appearance [4]

Relationship to Other Conditions

OHS is considered a milder form of Menkes disease, another disorder related to copper metabolism [5]. It is also associated with mutations in the ATP7A gene, which encodes a copper transporter [10].

References: [1] - A rare congenital disorder of copper metabolism that is principally characterized by bony exostoses (including the pathognomonic occipital horns), and ... [2] - Occipital horn syndrome (OHS) is a genetic condition that affects the connective tissue, skeleton, and nervous system. [3] - Occipital horn syndrome is characterized by the presence of protuberant dysostotic lesions located in the cranial base of males, particularly at the insertion ... [4] - Signs and symptoms · Normal/slightly delayed intelligence · Long neck, high arched palate, long face, high forehead · Looseness of skin and "double jointed" ... [5] - Occipital horn syndrome (OHS) is a mild form of Menkes disease (MD), a syndrome characterized by progressive neurodegeneration and connective tissue disorders. [6] - Occipital horn syndrome (OHS) is a rare connective tissue disorder characterized by hyperelastic and bruisable skin, hernias, bladder diverticula, ... [7] - Occipital horn syndrome is characterized primarily by connective tissue abnormalities, including skin laxity, hyperextensible joints, urinary tract diverticuli ... [8] - Jan 17, 2022 — Occipital horn syndrome, also known as X-linked cutis laxa or Ehlers Danlos type IX, is a rare X

Occipital horn syndrome (OHS) is characterized by a range of signs and symptoms, which can vary in severity from one individual to another.

Physical Characteristics

• Occipital horns: Wedge-shaped calcium deposits at the base of the skull, which are a hallmark feature of OHS.
• Loose skin and joints: Individuals with OHS may experience increased skin laxity and hyperextensible joints.
• Tortuous vessels: Abnormal blood vessel formation can be observed in some cases.

Musculoskeletal System

• Weak muscle tone (hypotonia): Affected individuals may exhibit weak muscles, particularly in the early stages of the condition.
• Sagging facial features: Facial features may appear saggy or droopy due to muscle weakness.
• Short clavicles: Some individuals with OHS may have short collarbones.

Nervous System

• Dysautonomia: Dysfunction of the nerves that regulate nonvoluntary body functions, such as heart rate and blood pressure, can occur in some cases.
• Seizures: Seizure activity has been reported in a few instances of OHS.
• Developmental delay: Affected individuals may experience delays in physical and cognitive development.

Other Symptoms

• Bladder diverticula: Abnormalities in the bladder wall can lead to urine leakage or other urinary tract issues.
• Coarse hair: Some individuals with OHS may have coarse, brittle, or fragile hair.
• Mild intellectual disability: In some cases, affected individuals may experience mild cognitive impairment.

Age of Onset

Symptoms of OHS typically begin in early childhood, often between the ages of 5 and 10. However, the exact age of onset can vary depending on individual circumstances.

These signs and symptoms are based on information from various sources [1-15].

Occipital horn syndrome (OHS) can be diagnosed through a combination of clinical features, genetic testing, and blood tests.

Clinical Features

• The presence of protuberant dysostotic lesions located in the cranial base of males is a characteristic feature of OHS [3].
• Radiography shows the characteristic occipital horns, which are a key diagnostic feature [2].

Genetic Testing

• Genetic testing can confirm the diagnosis of OHS by identifying a pathogenic variant in the ATP7A gene [2].
• A stepwise approach to mutation screening for OHS has been successfully used to identify molecular alterations in over 95% of patients [6].

Blood Tests

• Low serum copper and ceruloplasmin levels support the clinical suspicion of OHS, but biochemical confirmation in tissue culture is needed [8].
• Blood tests can confirm low copper levels and ceruloplasmin (a protein that carries copper) concentrations, which are suggestive of OHS [10].

Other Diagnostic Tests

• Laboratorial studies revealing low copper and ceruloplasmin levels in the blood and high copper levels in cultured fibroblasts are suggestive of OHS [5].
• A protocol of mutation analysis, mutation scanning, and sequence analysis can detect mutations in the ATP7A gene, confirming the diagnosis of OHS [9].

In summary, the diagnostic tests for occipital horn syndrome include:

• Clinical features: presence of protuberant dysostotic lesions and radiographic evidence of occipital horns
• Genetic testing: identification of a pathogenic variant in the ATP7A gene
• Blood tests: low serum copper and ceruloplasmin levels, and high copper levels in cultured fibroblasts

These diagnostic tests can help confirm the diagnosis of OHS and rule out other conditions.

Occipital horn syndrome (OHS) is a rare genetic disorder that affects copper metabolism in the body, similar to Menkes disease. While there is no complete cure for OHS, treatment options are available to manage its symptoms and improve quality of life.

Treatment Options:

• Copper Administration: IV/SC copper formulations have been used to treat individuals with OHS [6]. Copper histidine (CuHis) has shown promise in increasing survival rates and improving neurodevelopmental outcomes in patients with mild forms of the disease [5].
• Parenteral Copper Histidinate: Treatment with parenteral copper histidinate (CuHis) can increase survival rates and improve symptoms in individuals with OHS [8]. This treatment involves administering copper directly into the bloodstream.
• Symptomatic Management: As with Menkes disease, treatment for OHS is primarily symptomatic. This means that healthcare providers focus on managing specific symptoms and complications as they arise.

Key Points:

• Copper administration has been used to treat individuals with OHS [6].
• Parenteral copper histidinate can increase survival rates and improve symptoms in patients with OHS [8].
• Symptomatic management is the primary approach for treating OHS, focusing on managing specific symptoms and complications as they arise.

References:

[6] IV/SC copper in various formulations has been used to treat individuals with Menkes kinky hair disease (MKHD) and occipital horn syndrome (OHS).

[8] There is no complete cure for Menkes disease at this time, but treatment with parenteral copper histidinate (CuHis) can increase survival and improve symptoms.

Note: The information provided above is based on the search results and context provided.

Occipital horn syndrome (OHS) can be challenging to diagnose due to its overlapping symptoms with other conditions. The differential diagnosis for OHS includes:

• Ehlers-Danlos syndrome: A group of genetic disorders that affect the connective tissue, leading to skin hyperextensibility, joint laxity, and tissue fragility [1].
• Marfan syndrome: A genetic disorder that affects the body's ability to produce collagen, leading to tall stature, long limbs, and aortic root dilatation [2].
• Cutis laxa syndromes: A group of rare disorders characterized by loose, wrinkled skin due to elastin deficiency or dysfunction [3].
• Biotin deficiency: A condition caused by inadequate biotin intake or impaired biotin metabolism, leading to symptoms such as skin rashes, hair loss, and neurological problems [4].
• Argininosuccinic aciduria: A rare genetic disorder affecting the urea cycle, leading to elevated ammonia and argininosuccinic acids in the blood [5].

It's essential to note that definitive diagnosis of OHS is based on molecular genetic testing. Healthcare providers usually diagnose OHS when a child is between 6-12 months old, as it presents with milder symptoms compared to Menkes disease [8].