Ichthyosis is an uncommon group of genetic skin disorders distinguished by dry, thick, and scaly skin. It results in an excessive build-up of scales or hard-like skin due to abnormalities in the genes  that regulate the usual shedding of skin cells.

Ichthyosis is a term derived from the Greek word “ichthys”, meaning fish, just like skin often has a fish-scale-like visual appeal. It has various types, ranging from mild to severe, with different degrees of severity and indications.

Some common types are:

  1. Ichthyosis Vulgaris: The most common type fish-scale disease, is ichthyosis vulgaris. It causes dry, scaly, and rough skin that can appear thickened, particularly on the arms, legs and abdomen.

  2. Congenital Ichthyosiform Erythroderma: A brutal type of the disease present at birth, characterized by a broad range of reddening of the skin and the presence of large, plate-like scales is known as congenital ichthyosiform erythroderma.

  3. Epidermolytic: Epidermolytic Ichthyosis is also termed as bullous congenital ichthyosiform erythroderma, it is identified by extensive peeling off of skin and blisters, particularly in the initial phases of infancy.

  4. Lamellar Ichthyosis: An uncommon and noxious form, where the whole body is wrapped with large, plate-like scales that can be shredded in large sheets is known as Lamellar Ichthyosis.

Although the disease is not transferable, it can notably affect a person’s quality of life, inflicting agony, skin diseases, and in a few cases, physical constraints. For individuals impacted, prompt detection and appropriate therapy are essential for improving their overall health.

Causes of Ichthyosis

Genetic factors, notably abnormalities in genes important for the appropriate development and upkeep of the corneum, or the outermost covering of the epidermis is the primary cause. Parents could pass on these mutations to their progeny or they may develop on their own.

The genetic factors implicated and the specific type of ichthyosis influence the inheritance patterns. In some instances of ichthyosis, the condition may be triggered by a single mutation copy of the affected genes from either of the parents because of an autosomal dominant inheritance pattern. Other forms have an autosomal recessive pattern, meaning that the condition can occur only in two instances of the deficient gene—one from each parent.

When new (de novo) mutations in genes arise naturally during embryonic development instead of being inherited from parents, it may sometimes cause this disorder.

The typical scaly, dry skin of a condition called ichthyosis, is caused by specific mutations in genes that interact with numerous steps related to the development and peeling off of the corneum layer. Several genes have been linked to ichthyosis, including:

  1. FLG (Filaggrin): The most common form of the condition, ichthyosis vulgaris can be caused by mutations in the gene.

  2. ABCA12 (ATP-binding cassette transporter A12): Mutations in this gene can lead to severe forms of ichthyosis, such as harlequin and lamellar ichthyosis.

  3. TGM1 (Transglutaminase 1): Mutations in this gene can cause lamellar ichthyosis and other forms of autosomal recessive congenital ichthyosis.

  4. ALOXE3 (Arachidonate Lipoxygenase 3): Mutations in this gene can cause autosomal recessive congenital ichthyosis.

Understanding the specific genetic causes and inheritance patterns of ichthyosis is crucial for accurate diagnosis, genetic counselling, and exploring potential treatment options.

Types of Ichthyosis

A class of hereditary skin disorders known as ichthyosis is typified by thick, scaly, dry skin. Ichthyosis comes in a variety of forms, each with distinctive signs and various levels of severity. Typical forms consist of:

  1. Ichthyosis Vulgaris (IV): About 1 in 300 individuals have this type of a condition called ichthyosis, which is the most prevalent kind. Dry, rough, and scaly skin, especially on the legs, arms, and abdomen, are its defining characteristics. The scales could have a mosaic pattern or a fish-like appearance.
  2. X-Linked Ichthyosis (XLI): Males are most affected by this type, which can be brought on by an X-chromosome mutation in the genome. The trunk, neck, and extremities are often covered in brown or dark scales, and the skin is dry, rough, and scaly. Moreover, ocular opaqueness caused by XLI may impede vision.
  3. Lamellar Ichthyosis (LI): An uncommon and severe kind is called LI. Infants are frequently encased in a dense, plate-like layer, which is additionally referred to as a “collodion baby.” The skin appears thick, black, and scaly with huge, plate-like scales after the membrane sheds.

Rare forms of ichthyosis include:

  • Epidermolytic Ichthyosis (EI): Characterized by red, blistered, and denuded skin, often with thick scales and crusting.

  • Congenital Ichthyosiform Erythroderma (CIE): A severe form with widespread reddening of the skin, often with fine white scaling.

  • Harlequin Ichthyosis: One of the most severe forms, with thick, armour-like plates of skin covering the entire body at birth, often leading to respiratory distress and other life-threatening complications.

Even within the same family, there can be major variations in each type’s symptoms and severity. Several common symptoms and signs associated with different kinds of ichthyosis include thicker, dry, and scaly skin, intense itching, skin splitting and fissuring, and a higher risk for getting infections of the skin.

Symptoms and Signs

The most prevalent sign is an abundance of scales or skin shedding, which may appear in the form of tiny flakes or bigger, plate-like scaling. Ichthyosis is identified by scaly, dry, and thicker skin, and its severity may differ additionally.

Additionally, the skin may seem reddish or irritated, especially around regions with greater scales or builds that are splitting or cracking. Another common sign that can be made worse by irritation, cracking, and inflammation is intense itching.

According to the particular type, additional symptoms and signs might be:

  • Excessive skin cell loss that results in a scaly accumulation

  • Tightness or limitation of mobility in certain places as a result of deeper skin layers

  • Tearing or splitting of the skin, especially on the feet and hands

  • In severe circumstances, eclabion (escape of the lips) or the condition (outward tilting of the eyes) may occur.

  • Sweating too much or being intolerant to heat

  • Alopecia (hair loss) or, in some instances, abnormal growth of the hair

  • Anomalies of the nails, including thickening or ridging

Even under the same form of ichthyosis, there can be significant differences in the intensity and particular symptoms across people. Certain varieties could also come with other characteristics or side effects, such as brain disorders, a hearing impairment, or a higher chance of skin infections.

Diagnosis

Physical Examination

The process usually entails a thorough evaluation that includes a physical examination, a study of the patient’s medical history, and a variety of tests to figure out the exact type and extent of the problem.

The medical professional will closely examine the patient’s skin after the physical inspection, looking for tell tale symptoms of ichthyosis like:

  • The skin peeling or scaling

  • rough or swollen skin tone

  • Fissured or broken skin

  • Inflammatory or red

  • Pattern and location of skin involvement

The way the skin symptoms occur and propagate could provide significant clues to identify the particular kind of ichthyosis that may be prevalent.

Skin Biopsy

A sample of the skin may be necessary in some circumstances. This entails removing a little bit of skin cells for analysis under a microscope. A tissue sample can help rule out other possible skin conditions and differentiate among various kinds of ichthyosis.

Genetic Testing

For many types of ichthyosis, genetic testing is essential to the diagnosis. Healthcare practitioners may identify particular gene mutations that are associated with different kinds by analysing the individual’s DNA. For a precise diagnosis, prognosis, and possible treatment options, this information is essential.

Prenatal Testing

Prenatal testing alternatives could be offered to individuals who have a threat or have a prior history of this disorder. These assays are capable of identifying ichthyosis in the growing foetus throughout gestation. Typical prenatal testing techniques consist of:

  • Sampling of Chorionic Villus (CVS)

  • Amniocentesis

  • Genetic testing before implantation (PGT)

During pregnancy, prenatal examinations can help them make educated decisions and get ready for the arrival of their kid.

It is noteworthy that a multidisciplinary team of dermatology doctors, genetic counsellors, and other specialists may be engaged with the testing process in order to guarantee a precise diagnosis and create a suitable treatment strategy.

Treatment Options

Keeping the skin hydrated and avoiding severe drying and peeling is the primary therapy. Usually, a mix of moisturisers, lotions, and other topical treatments is used to accomplish this.

Moisturisers and Skin care Creams: The main important treatment is a cream or moisturiser that is rich in emollients. These products strengthen the skin’s protective barrier and help in retaining hydration in the skin. Petroleum-based products, glycerin-based lotions, and compositions containing ceramide are a few often used moisturisers. It can be necessary to apply them multiple times a day, particularly following a bath.

Oral Medications: In a few cases, to aid ichthyosis signs, oral medications may be advised by medical professionals. Retinoids, like acitretin, might assist in regulating peeling off of dead skin cells and enhance the appearance of an individual’s skin. These medications do, however, have possible adverse reactions and ought to be carefully monitored by a medical professional.

Other Therapies: Based upon the type and brutality of ichthyosis, even more treatments might be suggested. The treatments include:

  • Keratolytic agents: Alpha-hydroxy acid or urea-containing dermal moisturizers or lotions may help in relaxing and eliminating excessive scale deposition.

  • Phototherapy: Under specific instances, being exposed to particular UV radiation wavelengths may enhance the texture of skin.

  • Systemic retinoids: Under medical surveillance, oral retinoids such as tretinoin might be advised for severe instances.

  • Topical calcineurin inhibitors: In particular instances of a condition called, ichthyosis, these drugs can help reduce discomfort while improving the look of the skin.

Getting help from professionals is necessary for proper treatment, evaluation and monitoring of the condition. Often a database of the healthcare professionals is maintained by the individual advocacy groups with expertise in ichthyosis, making it convenient for victims to find experienced  dermatologists, geneticists, and other expert practitioners in the field. Personalised care and guidance can be provided by these medical professionals, making sure of the best results for patients.

Apart from social media platforms and support for patient groups, there are other educational materials alternatives including seminars, webinars, and educational materials.. These medications can help patients and their families to stay up-to-date on the most recent investigation, treatment and management of strategies for ichthyosis.