autosomal recessive congenital ichthyosis 9

Autosomal Recessive Congenital Ichthyosis 9 (ARCI9) is a rare genetic disorder that affects the skin's ability to produce and maintain its natural moisture barrier.

• It is caused by a homozygous mutation in the CERS3 gene, which is located on chromosome 15q26 [3].
• This 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 disorder [4].
• ARCI9 is characterized by abnormal skin scaling over the body, which can range from mild to severe [6][8].
• The main phenotypes associated with ARCI9 include abnormality of head or neck, eclabion, abnormality of limbs, palmar hyperlinearity, and abnormality of the epidermis [2].

It's worth noting that ARCI9 is a specific subtype of Autosomal Recessive Congenital Ichthyosis (ARCI), which is a group of rare disorders of keratinization classified as nonsyndromic forms of ichthyosis [5][7].

Clinical Characteristics of Autosomal Recessive Congenital Ichthyosis

Autosomal recessive congenital ichthyoses (ARCI) are lifelong skin disorders with generalized scaling and variable erythema that typically manifest at birth or early infancy. The signs and symptoms of ARCI can vary in severity, but common features include:

• Generalized scaling: Thick, dry scales cover the entire body, often accompanied by a more or less severe erythroderma (redness and inflammation of the skin).
• Erythema: Variable degrees of redness and inflammation of the skin.
• Collodion membrane: A tight, shiny layer of dead skin cells that covers the body at birth, which may not be distinguishable based on clinical grounds prior to onset of specific symptoms [10].

In some cases, individuals with severe involvement can experience additional complications, such as:

• Ectropion: Drooping eyelids.
• Eclabium: Ears that are folded back against the head.
• Scarring alopecia: Hair loss due to scarring.
• Loss of eyebrows and lashes [4].

It's essential to note that the severity and specific symptoms of ARCI can vary significantly among individuals, even within the same family.

Based on the provided context, here are some diagnostic tests associated with autosomal recessive congenital ichthyosis (ARCI):

• Molecular genetic testing: This is a recommended test for diagnosing ARCI, especially when a molecular diagnosis has been established in the proband. It can confirm the presence of mutations in genes such as CERS3 [5].
• Genetic testing: Genetic testing can be used to diagnose ARCI and identify the underlying cause of the disease. This type of testing can include gene-targeted testing, which can detect specific mutations in genes associated with ARCI [10].
• Clinical genetic test: A clinical genetic test offered by Intergen for conditions (1) includes testing for autosomal recessive congenital ichthyosis 9, which involves analyzing the CERS3 gene [5].

It's worth noting that diagnostic tests may vary depending on individual cases and the specific type of ARCI being diagnosed. However, molecular genetic testing and genetic testing are generally considered important tools in diagnosing this condition.

References: [5] -

Treatment Options for Autosomal Recessive Congenital Ichthyosis

According to recent studies, treatment options for autosomal recessive congenital ichthyosis (ARCI) have been explored, with varying degrees of success. One such option is the use of oral isotretinoin.

• Oral Isotretinoin: A study published in 2022 by A Petak et al. [9] reported that treatment with oral isotretinoin was effective in improving ichthyosis without any significant side effects. This suggests that oral isotretinoin may be a viable treatment option for patients with ARCI.

Other Treatment Options

While the effectiveness of other treatments, such as topical retinoids and biologics, is still being researched, they may also hold promise for treating ARCI.

• Topical Retinoids: Topical retinoids have been used to treat various skin conditions, including ichthyosis. However, their efficacy in treating ARCI specifically is not well established.
• Biologics: Biologic agents, such as those targeting specific proteins involved in skin cell growth and differentiation, may also be explored as potential treatments for ARCI.

Important Considerations

It's essential to note that the effectiveness of these treatment options can vary depending on individual factors, such as the severity of symptoms, patient adherence, and environmental factors. Additionally, the long-term effects of these treatments are not yet fully understood.

References: [9] A Petak et al. (2022). Treatment with oral isotretinoin in patients with autosomal recessive congenital ichthyosis: a case series. [Cited by 3].

Differential Diagnosis of Autosomal Recessive Congenital Ichthyosis 9 (ARCI9)

Autosomal recessive congenital ichthyosis-9 (ARCI9) is a rare genetic disorder caused by a homozygous mutation in the CERS3 gene on chromosome 15q26 [4]. When considering the differential diagnosis of ARCI9, it's essential to rule out other forms of neonatal erythroderma and syndromic ichthyoses.

Other Forms of Neonatal Erythroderma:

• Syndromic ichthyoses, such as Netherton syndrome and KID syndrome [10]
• Congenital ichtyosis with erythema [10]

Genetic Disorders:

• Recessive X-linked ichthyosis
• Semidominant ichthyosis vulgaris

Key Points to Consider:

• ARCI9 is a rare disorder caused by a specific genetic mutation.
• Differential diagnosis includes other forms of neonatal erythroderma and syndromic ichthyoses.
• Genetic disorders, such as recessive X-linked ichthyosis and semidominant ichthyosis vulgaris, should also be considered.

References:

[4] - Autosomal recessive congenital ichthyosis-9 (ARCI9) is caused by homozygous mutation in the CERS3 gene (615276) on chromosome 15q26. [10] - Differential diagnosis includes other forms of neonatal erythroderma, especially syndromic ichthyoses (e.g. Netherton syndrome, KID syndrome), congenital ...