focal dermal hypoplasia

Focal dermal hypoplasia, also known as Goltz syndrome, is a rare genetic disorder that primarily affects the skin, skeleton, eyes, and face [7]. It is characterized by distinctive skin abnormalities and a wide variety of defects in other organ systems [6].

The primary feature of focal dermal hypoplasia is patchy dermal hypoplasia, with herniation of fat through defects in the dermis [8][12]. This can manifest as soft, yellow-pink cutaneous nodules on the skin [4]. Other skin manifestations include atrophic and hypoplastic areas of skin, cutis aplasia, telangiectases, and pigmentary changes [3][4].

In addition to skin abnormalities, focal dermal hypoplasia can also affect the skeletal system, eyes, and face. The disorder is typically inherited in an X-linked dominant pattern, meaning that females are more commonly affected than males [12][14]. Males with the condition often do not survive infancy due to the severity of their symptoms.

Focal dermal hypoplasia is a multisystem disorder that can also affect other organ systems, including the gastrointestinal, genitourinary, neurological, and cardiovascular systems [2].

References: [1] Not directly relevant [2] 4, 13 [3] 3 [4] 4 [6] 6 [7] 7 [8] 8 [12] 12, 14 [14] 14

Focal dermal hypoplasia (FDH) is a rare genetic disorder that primarily affects the skin, skeleton, eyes, and face. The signs and symptoms of FDH can vary widely among individuals, but most affected people have skin abnormalities.

Common Signs and Symptoms:

• Skin Abnormalities: Linear hypoplastic (thinned) streaks which follow the lines of Blaschko are a hallmark feature of FDH [1]. These streaks can be present from birth and may be accompanied by other skin manifestations such as cutis aplasia, telangiectases, and fat nodules.
• Skeletal Abnormalities: Individuals with FDH may have skeletal abnormalities, including limb malformations, which can range from mild to severe [3].
• Eye and Face Abnormalities: Eye and face abnormalities are also common in individuals with FDH. These can include colobomas (a hole or gap in the iris), cataracts, and facial asymmetry.
• Intellectual Disability: Some individuals with FDH may have intellectual disability, although intelligence is typically unaffected in most cases [5].

Other Possible Signs and Symptoms:

• Fat Nodules: Fat nodules can be present on the skin, particularly on the face and neck.
• Telangiectases: Telangiectases (small dilated blood vessels) can appear on the skin, often in a linear pattern following the lines of Blaschko.

It's essential to note that the severity and range of symptoms can vary greatly among individuals with FDH. Males usually have milder signs and symptoms than females [3].

References: [1] Context 8 [2] Context 8 [3] Context 3 [4] Context 13 [5] Context 5

Diagnostic Tests for Focal Dermal Hypoplasia

Focal dermal hypoplasia (FDH) can be diagnosed through a combination of clinical evaluation and genetic testing.

• Clinical Evaluation: A complete total body skin examination is essential to note features that contribute to early diagnosis and genetic testing. Careful physical examination, including complete total body skin examination, is crucial in diagnosing FDH ([8][9]).
• Genetic Testing: DNA testing for the PORCN gene is available to confirm the diagnosis of FDH ([2]). This test can be performed on various samples, such as cord blood, cystic hygroma fluid, dried blood spot (DBS), or extracted DNA ([3]).
• Diagnostic Criteria: A diagnosis of FDH is made based on clinical features, and genetic testing may be used to confirm the diagnosis in individuals with characteristic limb malformations and skin manifestations ([11]).

Additional Diagnostic Tools

Other diagnostic tools that may be helpful in establishing a diagnosis of FDH include:

• Model questionnaires, protocols, or checklists that guide clinicians and laboratory personnel in the diagnostic procedure
• A list of cell biology/biochemical tools used for laboratory diagnosis of specific disease groups/subgroups ([12])

Important Considerations

It is essential to note that a diagnosis of FDH should be considered in patients with either multiple skin manifestations or one typical skin manifestation in addition to characteristic limb malformations. Genetic counseling and testing may also be necessary to confirm the diagnosis and provide guidance on family planning and genetic risk assessment.

References:

[2] DNA testing for the PORCN gene is available to confirm the diagnosis of FDH. [3] Various samples, such as cord blood, cystic hygroma fluid, dried blood spot (DBS), or extracted DNA, can be used for genetic testing. [8] Careful physical examination, including complete total body skin examination, is crucial in diagnosing FDH. [9] A diagnosis of FDH is made based on clinical features. [11] Genetic testing may be used to confirm the diagnosis in individuals with characteristic limb malformations and skin manifestations.

Focal dermal hypoplasia (FDH) is a rare genetic disorder that primarily affects the skin, skeleton, eyes, and face. While there is no specific cure for FDH, various treatments can help manage its symptoms.

Symptomatic Treatment

Treatment for FDH is usually symptomatic, focusing on managing the various abnormalities associated with the condition. This may include:

• Dermatological care: Topical creams or ointments may be prescribed to treat skin lesions and telangiectasia (dilated blood vessels).
• Orthopedic care: Surgery may be necessary to correct skeletal deformities, such as clubfoot or limb abnormalities.
• Ophthalmologic care: Treatment for eye anomalies, including cataracts, glaucoma, or strabismus, may involve surgery or other interventions.
• Dental care: Dental problems, such as hypodontia (fewer teeth than normal) or enamel dysplasia, can be addressed through dental procedures.

Other Treatments

In some cases, additional treatments may be considered:

• Photodynamic therapy: This treatment has been used to manage painful excessive granulation tissue in patients with FDH.
• Surgical excision: Surgical removal of lesions or abnormalities may be necessary in some cases.
• Pulsed-dye laser therapy: This treatment can help reduce telangiectasia.

Genetic Considerations

It's essential to note that FDH is a genetic disorder, and while these treatments can manage symptoms, they do not address the underlying genetic cause. Genetic counseling may be recommended for affected individuals and their families.

According to recent studies (e.g., [11] in the provided context), approximately 90% of individuals with FDH are female, and the condition is caused by variants in the PORCN gene at Xp11.23. This information highlights the importance of genetic considerations in managing FDH.

Please consult a healthcare professional for personalized advice on treating focal dermal hypoplasia.

Differential Diagnoses for Focal Dermal Hypoplasia

Focal dermal hypoplasia (FDH) is a rare genetic disorder that primarily affects the skin, skeleton, eyes, and face. When diagnosing FDH, it's essential to consider other conditions that may present similar symptoms. Here are some differential diagnoses for FDH:

• Micropthalmia with linear skin defects (MLS): This condition is characterized by microphthalmia, sclerocornea, linear skin defects, and agenesis of the corpus callosum [2].
• Incontinentia pigmenti (IP): IP is a genetic disorder that affects the skin, hair, nails, and central nervous system. It's essential to distinguish FDH from IP, as they share some similar symptoms [4][8].
• Proteus syndrome: This rare genetic disorder is characterized by overgrowth of various tissues, including skin, bones, and organs. While it shares some similarities with FDH, the two conditions have distinct features [7].
• Aplasia cutis congenita: This condition is characterized by a congenital absence or malformation of the skin. It's essential to consider this diagnosis in cases where FDH is suspected [7].
• Epidermal nevus: This rare genetic disorder affects the skin and can present with similar symptoms to FDH, such as linear skin defects and skin thickening [14].

Key Points

• Focal dermal hypoplasia (FDH) is a rare genetic disorder that primarily affects the skin, skeleton, eyes, and face.
• Differential diagnoses for FDH include micropthalmia with linear skin defects (MLS), incontinentia pigmenti (IP), proteus syndrome, aplasia cutis congenita, and epidermal nevus.
• Accurate diagnosis of FDH requires a thorough understanding of its clinical features and differentiation from other rare genetic disorders.

References

[1] Not provided [2] Jun 23, 2019 [3] Not provided [4] Focal dermal hypoplasia must also be distinguished from microphthalmia with linear skin defects (MLS) syndrome (also called MIDAS for microphthalmia, ... [5] Not provided [6] by TJ Fete — Associated anomalies include dental, hair, nail, and skeletal abnormalities. [7] Proteus syndrome and aplasia cutis congenita are rare genetic disorders that can present with similar symptoms to FDH. [8] Incontinentia pigmenti (IP) is a genetic disorder that affects the skin, hair, nails, and central nervous system. [9] Not provided [10] Focal dermal hypoplasia (FDH; MIM #305600), also known as Goltz syndrome or Goltz-Gorlin syndrome, is an X-linked dominant multisystem disorder that is lethal in utero in males . [11] PORCN-related developmental disorders include a spectrum of highly variable multisystem disorders caused by developmental abnormalities in mesodermal and ectodermal structures primarily involving the skin, limbs, eyes, and face. [12] Prenatal diagnosis for pregnancies at increased risk and preimplantation genetic diagnosis are possible if the pathogenic variant in the family has been identiied. [13] Focal dermal hypoplasia (Goltz syndrome) is a rare genetic multisystem disorder primarily involving the skin, skeletal system, eyes, and face. [14] Other differential diagnosis to be considered is epidermal nevus, Bart syndrome, Adams-Oliver syndrome, ectodermal dysplasia, and congenital erosive and vesicular dermatoses.