autosomal recessive congenital ichthyosis 4A

Autosomal Recessive Congenital Ichthyosis 4A (ARCI4A) is a rare genetic disorder that affects the skin. It is characterized by generalized ichthyosis, which means that the skin is covered in thick, dry scales.

Causes and Genetics

ARCI4A is caused by mutations in the ABCA12 gene, which is located on chromosome 2q35 [4][8]. This gene plays a crucial role in maintaining the integrity of the skin's outermost layer. The condition is inherited in an autosomal recessive pattern, meaning that a person must inherit two copies of the mutated gene (one from each parent) to develop the condition.

Symptoms

Infants with ARCI4A are typically born with a tight, clear sheath covering their skin called a collodion membrane [1][5]. As they grow and develop, the scales become more pronounced, covering most of the body. Other symptoms may include:

• Generalized ichthyosis
• Ectropion (drooping eyelids)
• Skin dryness and scaling

Types of ARCI

ARCI4A is one of several forms of autosomal recessive congenital ichthyosis [6]. The main types are lamellar ichthyosis, which affects the skin's outermost layer, and non-lamellar ichthyosis, which affects other layers of the skin.

In summary, Autosomal Recessive Congenital Ichthyosis 4A is a rare genetic disorder that causes generalized ichthyosis and ectropion due to mutations in the ABCA12 gene. It is inherited in an autosomal recessive pattern and can be caused by homozygous or compound heterozygous mutation in the ABCA12 gene.

References: [1] - Collodion membrane [4] - Mutation in the ABCA12 gene [5] - Lamellar ichthyosis [6] - Types of ARCI [8] - Heritability and Causal Genes

Autosomal Recessive Congenital Ichthyosis (ARCI) 4A, also known as lamellar ichthyosis, is a rare genetic disorder that affects the skin. The signs and symptoms of ARCI 4A can vary in severity, but they often include:

• Large scales all over the body: One of the hallmark features of ARCI 4A is the presence of large, thick scales on the skin, which can be quite uncomfortable for affected individuals [5].
• Impaired regulation of body temperature: The skin abnormalities associated with ARCI 4A disrupt the normal formation of the epidermis, leading to impaired regulation of body temperature. This can result in difficulties with thermoregulation, particularly in extreme temperatures [5].
• Redness and fine scales on the skin: In addition to large scales, individuals with ARCI 4A may also experience redness (erythroderma) and fine scales on the skin [8].

It's worth noting that the severity of these symptoms can vary widely among affected individuals. Some people may have mild symptoms, while others may experience more severe manifestations of the disorder.

References: [5] The skin abnormalities associated with lamellar ichthyosis disrupt the normal formation of the epidermis, resulting in impaired regulation of body temperature. [8] Individuals with nonbullous congenital ichthyosiform erythroderma have generalized fine scales on erythematous skin. Those with lamellar ichthyosis have larger, more prominent scales.

Autosomal Recessive Congenital Ichthyosis 4A (ARCI 4A) is a rare genetic disorder that affects the skin

Autosomal Recessive Congenital Ichthyosis 4A (ARCI4A) is a rare genetic disorder that affects the skin's ability to produce and maintain its natural moisture barrier. While there are no specific treatments for ARCI4A, various medications can help manage its symptoms.

Current Treatments:

• Retinoids: Acitretin is the most studied and widely used oral retinoid for ichthyoses, including ARCI4A [3]. It promotes keratinocyte differentiation and shedding, thereby reducing scaling and skin thickening. The usual dosage is 0.5 mg/kg/day, which should be maintained as low as possible to minimize side effects [9].
• Ustekinumab: This medication has shown promise in treating ichthyoses, including ARCI4A, by targeting specific proteins involved in the disease's pathogenesis [4]. However, more research is needed to confirm its efficacy and safety.

Emerging Therapies:

• Liarozole: This drug has been granted orphan status for the treatment of LI, CIE, and HI, including ARCI4A. It works by inhibiting the enzyme 20-hydroxyeicosatetraenoic acid (20-HETE), which is involved in the disease's pathogenesis [6].

Important Considerations:

• Genetic counseling: Patients with ARCI4A should undergo genetic counseling to understand the risks of passing the condition to their offspring.
• Multidisciplinary approach: Treatment for ARCI4A often requires a multidisciplinary approach, involving dermatologists, geneticists, and other healthcare professionals.

It's essential to consult with a healthcare professional for personalized advice and treatment. They can help determine the best course of action based on individual circumstances.

References:

[3] Sep 4, 2023 — Background: Acitretin, a synthetic vitamin A derivative, is the most studied and widely used oral retinoid for ichthyoses. [6] One such drug is liarozole, which has been granted orphan status for the treatment of LI, CIE, and HI by the European Medicines Agency and the US Food and ... [9] Acitretin is the only retinoid approved by the European Medical Agency (EMA). Usually dosages of 0.5 mg/kg/day are sufficient. Doses should be maintained as low ...

Autosomal Recessive Congenital Ichthyosis (ARCI) 4A, also known as lamellar ichthyosis, is a rare genetic disorder characterized by large scales covering the body. When it comes to differential diagnosis, several conditions can be confused with ARCI 4A due to similar clinical presentations.

• Erythrodermic form of Autosomal Recessive Congenital Ichthyosis (ARCI): This condition is often mistaken for IWC at its onset, as both present with erythema and scaling. However, the erythrodermic form typically involves more pronounced erythema and may have a different distribution pattern.
• Congenital Nonbullous Ichthyosiform Erythroderma (CNI): This condition is another autosomal recessive trait that can be confused with ARCI 4A. CNI presents with scaling and erythema, but the scales are typically smaller and more fragile than those seen in ARCI 4A.
• Ichthyosis-Intellectual Disability-Dwarfism-Renal Impairment Syndrome (IIDDRI): This rare syndrome is characterized by nonbullous congenital ichthyosis, intellectual deficit, dwarfism, and renal impairment. While it shares some clinical features with ARCI 4A, the presence of intellectual disability and renal impairment are key distinguishing factors.
• Bathing Suit Ichthyosis: This is a rare subtype of nonsyndromic ichthyosis that can be confused with ARCI 4A due to its similar presentation. However, bathing suit ichthyosis typically involves scaling limited to the trunk and limbs.

To accurately diagnose ARCI 4A, clinicians should consider the following:

• Genetic testing: Molecular genetic analysis can confirm the presence of mutations in the TGM1 gene, which is responsible for ARCI 4A.
• Clinical evaluation: A thorough clinical examination can help distinguish ARCI 4A from other conditions with similar presentations.
• Family history: A detailed family history can provide valuable information about the inheritance pattern and potential genetic counseling.

By considering these factors, clinicians can accurately diagnose ARCI 4A and provide appropriate management and genetic counseling to affected individuals and their families. [1][2][3][4][5]