microphthalmia with limb anomalies

Clinical Description

Microphthalmia with limb anomalies, also known as Waardenburg anophthalmia syndrome or ophthalmoacromelic syndrome (OAS), is a rare developmental disorder characterized by bilateral or unilateral microphthalmia, clinical anophthalmia, synostosis, syndactyly, oligodactyly, and polydactyly [13].

Key Features

• Bilateral or unilateral microphthalmia or anophthalmia
• Synostosis (fused bones)
• Syndactyly (webbed fingers or toes)
• Oligodactyly (missing fingers or toes)
• Polydactyly (extra fingers or toes)
• Long-bone hypoplasia and renal, venous, and vertebral anomalies may also be present [9]

Ocular Features

• Patients have either microphthalmia or anophthalmia which may be present unilaterally or bilaterally
• The MRI in several patients has revealed complete absence of the globes, optic nerves, chiasm, and optic tracts [4]

Other Characteristics

• Impaired intellectual development is present in about half of affected individuals [9]
• Limb malformations include fused fingers or toes, missing fingers or toes, and extra fingers or toes [7]

Note: The above description is based on the information provided in the search results.

Common Signs and Symptoms of Microphthalmia with Limb Anomalies

Microphthalmia with limb anomalies, also known as ophthalmo-acromelic syndrome (OAS), is a rare developmental disorder characterized by bilateral microphthalmia. The condition is associated with various physical abnormalities, including:

• Bilateral Microphthalmia: A decrease in the size of both eyeballs and orbits.
• Limb Malformations: Missing fingers or toes (oligodactyly) are the most common hand and foot malformation seen in OAS. Other frequent limb malformations include oligo-/syndactyly and split hand/foot.
• Long-bone Hypoplasia: Underdevelopment of long bones, which can lead to short stature or other skeletal abnormalities.
• Renal, Venous, and Vertebral Anomalies: Abnormalities in the kidneys, veins, and spine may also be present.
• Impaired Intellectual Development: About half of affected individuals experience impaired intellectual development.

Additionally, some people with microphthalmia with limb anomalies may exhibit:

• Abnormal Eyebrow Morphology
• Ridged, Dysplastic, or Hypoplastic Nails
• Sparse or Absent Hair

These physical abnormalities can vary in severity and combination among individuals with microphthalmia with limb anomalies.

Diagnostic Tests for Microphthalmia with Limb Anomalies

Microphthalmia with limb anomalies, also known as ophthalmo-acromelic syndrome (OAS), is a rare developmental disorder characterized by bilateral microphthalmia and malformations of the hands and feet. Diagnostic tests are essential to confirm the condition and rule out other possible causes.

Genetic Testing According to search results [5], genetic testing can be used to diagnose microphthalmia with limb anomalies. A homozygous mutation in the SMOC1 gene (608488) on chromosome 14q24 is associated with this condition [7].

Molecular Genetics Tests A 61-gene panel that includes assessment of non-coding variants may also be useful for patients with a clinical suspicion or diagnosis of microphthalmia, anophthalmia, or other related conditions [2]. This test can help identify genetic mutations that may contribute to the development of microphthalmia with limb anomalies.

Imaging Studies Imaging studies such as MRI may reveal optic nerve aplasia/hypoplasia, hippocampal malformations, structural abnormalities of the pituitary gland, and agenesis of the corpus callosum [8]. These findings can help confirm the diagnosis of microphthalmia with limb anomalies.

Other Diagnostic Tests While not specifically mentioned in the search results, other diagnostic tests such as clinical tests (20 available) may also be used to diagnose microphthalmia with limb anomalies. These tests may include molecular genetics tests, imaging studies, and other specialized tests.

References: [2] - A 61-gene panel that includes assessment of non-coding variants. [5] - Microphthalmia with limb anomalies, also known as ophthalmo-acromelic syndrome (OAS). [7] - Homozygous mutation in the SMOC1 gene (608488) on chromosome 14q24. [8] - MRI may reveal optic nerve aplasia/hypoplasia, hippocampal malformations, structural abnormalities of the pituitary gland, and agenesis of the corpus callosum.

Current Treatment Options for Microphthalmia with Limb Anomalies

Microphthalmia with limb anomalies (MLA) is a rare condition that affects the development of the eyes and limbs. While there is no specific treatment available to cure MLA, various medical interventions can help manage its symptoms and associated complications.

• Surgical correction: Some individuals with MLA may benefit from surgical procedures to correct limb abnormalities, such as clubfoot or cleft palate [1]. However, these surgeries are typically performed on a case-by-case basis and depend on the severity of the condition.
• Visual aids: Individuals with some vision (if microphthalmia is not severe) may use visual aids like glasses or contact lenses to improve their eyesight [2].
• Prenatal medication exposure: Research suggests that prenatal medication exposure can contribute to fetal malformations, including MLA. However, there is no established treatment for MLA related to prenatal medication exposure [5].

Immunosuppressant Medication

A recent study by C Dubucs (2024) highlights the potential use of mycophenolate mofetil (MMF), an immunosuppressant medication, in treating various conditions. While MMF is not specifically mentioned as a treatment for MLA, its application in organ transplantation and other medical contexts may provide insights into managing related complications [8].

Current Research and Future Directions

Research on MLA is ongoing, with studies exploring the genetic and environmental factors contributing to this condition. As new information becomes available, it's essential to consult with healthcare professionals for personalized advice and treatment.

References:

[1] Context result 3 [2] Context result 1 [5] Context result 5 [8] Context result 8

Differential Diagnosis of Microphthalmia with Limb Anomalies

Microphthalmia with limb anomalies, also known as ophthalmo-acromelic syndrome (OAS), is a rare developmental disorder characterized by bilateral microphthalmia or anophthalmia, synostosis, syndactyly, oligodactyly and/or polydactyly. When diagnosing this condition, it's essential to consider differential diagnoses that may present similar symptoms.

Possible Differential Diagnoses:

• Lenz Microphthalmia Syndrome (LMS): This syndrome is characterized by microphthalmia or anophthalmia, and is a differential diagnosis for MLA. LMS is caused by mutations in the RAB3GAP1 gene [9].
• Cryptophthalmos: This condition is characterized by the absence of one or both eyelids, and can be associated with other limb anomalies [14].
• Cyclopia: This rare congenital anomaly involves the fusion of the eyes into a single eye, and can be associated with microphthalmia and other limb defects [14].
• Synophthalmia: This condition is characterized by the partial or complete fusion of the eyes, and can be associated with microphthalmia and other limb anomalies [14].

Key Features to Consider:

When considering differential diagnoses for microphthalmia with limb anomalies, it's essential to look for key features such as:

• Bilateral involvement: The presence of bilateral microphthalmia or anophthalmia is a hallmark of MLA.
• Limb malformations: Synostosis, syndactyly, oligodactyly and/or polydactyly are common limb anomalies associated with MLA.
• Genetic inheritance: Microphthalmia can exhibit a hereditary pattern, making it essential to complete eye examination of both parents and obtain a three-generation family history of eye anomalies [14].

References:

[9] by Y Lu · 2024 — Lenz microphthalmia syndrome (LMS) is a differential diagnosis for MLA. LMS is characterized by microphthalmia or anophthalmia, and is caused by mutations in the RAB3GAP1 gene. [14] Microphthalmia can exhibit a hereditary pattern. Therefore, it is crucial to complete eye examination of both parents and to obtain a three-generation family history of eye anomalies, including microphthalmia and coloboma.