Nevus Comedonicus: In-depth Guide to cure your Nevus Comedonicus

Nevus Comedonicus

The rare condition Nevus comedonicus (NC) was first described in 1895 by Kofmann. It is considered an epidermal nevus. Nevus comedonicus is characterized by a clustered, dilated follicular open with dark keratin blocks. Kofmann had initially suggested that the condition be called ‘comedo nudus.’

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Nevus comedonicus (NC), also known as comedo nudus, refers to closely arranged, grouped papules with keratinous plugs at their centers. It can be present from birth or later. NC syndrome refers to comedo nevus that presents with extracutaneous manifestations.

These may include the central nervous system (CNS), neurological, spinal abnormalities, skeletal, ophthalmologic, and neurological disorders. This case describes a child suffering from NC syndrome characterized by neurological, lean, and CNS abnormalities.

What is a Comedo nevus?

A comedo-nevus is a hair follicle nevus. It’s also called ‘comedone-nevus’ or ‘nevus comedonicus (1).

A comedo-nevus is an uncommon type of epidermal or birthmark (a pilosebaceous hamartoma) in which there is a small collection of keratin-filled follicles. Because there are no comedones, it is better called follicular-keratotic nude.

What are the clinical characteristics of comedo-nevus?

The common condition of comedo nevus can be present from birth or develop in childhood. Both males and females can be affected. Puberty is when lesions tend to grow faster. It can be located anywhere on the human body but often appear on the upper extremities, trunk, neck, and face.

They look like comedones because they are composed of closely grouped, slightly elevated papules with central keratinous plugs. They can be found in a linear, unidirectional, unilateral, or bilateral distribution. Sometimes they follow Blaschko’s lines.

What causes a comedo-nevus?

Although the exact cause of comedo-nevus is unknown, it is believed to be caused by cutaneous mosaicism, a line of cells with a genetic defect. The cells could spread to other comedo nuevi if the error is detected early in the embryo’s development.

Some patients have had FGFR2 mutations detected in their naevi. FGFR2 is the same gene as Apert syndrome, a more severe genetic condition. The comedo nevus could be a mosaic of Apert disorder (some cells may have the abnormal gene, and others have the normal gene).

Craniofacial Dysostosis is a condition that causes abnormalities in the bone structure and facial appearance of the skull and faces. Apert syndrome patients often have severe acne. It can also occur within a comedo t nusus.


It is not known what the exact cause of this condition is. Nevus comedonicus can be described as an epidermal nude, which develops from the hair follicle. Another opinion states that it is a mesodermal hamartoma.

It has been suggested that genetic mosaicism is part of the etiology for nevus comedonicus.


According to some reports, the prevalence ranges from 1 in 45,000 to 1 to 100,000. Males and women can be affected equally. There is no predisposition.

There has not been any increase in incidence among people of a particular ethnicity. The majority of cases occur before the age of 10 years.


The pathogenesis is caused by a mutation in Fibroblast Growth Factor Receptor 2(FGFR2) and increased expression of interleukin-1 alpha. Gamma-secretase, filaggrin are also possible causes.

Recent research has highlighted the importance of somatic mutations in NEK9 in nevus camedonicus. NEK9 is believed to play a vital role in the regulation and maintenance of follicular homeostasis.

NEK9 mutations cause increased phosphorylation at Thr210. It indicates activation of NEK9 associated kinase.

Other changes related to the formation of comedones in nevus camedonicus include loss of markers for follicular differentiation and ectopic expressions of keratin 10.

Recent research suggests that ABCA 12 may be involved in the formation of comedones in nevus camedonicus.


Skin biopsy shows the characteristic features of comedones: dilation of the follicular Ostia and keratin.

Signs and Symptoms of Nevus Comedonicus


There are many epidermal nevus disorders. The severity, prognosis, and symptoms of epidermal nevus syndromes can vary depending on its type and whether there are extra-cutaneous symptoms. These disorders can also go in their onset and progression.

The epidermal nevi are also known as “hamartomas,” a vague term that refers to benign tumor-like malformations. They can affect every place of the body. “Hamartomas” consist of mature cells and tissues commonly found in the affected region.

There are many types of epidermal cancers. They differ in their main components. Congenital epidermal nevi usually appear as a small patch or a plaque of skin overgrown.

Epidermal nevi can often be found on the trunk, limbs, and scalp. Epidermal nevi may be evident and striking or subtle and hard to spot.

Epidermal nevi of the face and head are more likely to be linked with malformations in the eyes, brain, and cranial bones. The trunk epidermal nevi are more likely to be related to abnormal curvature, hip malformation, and deformities of arms and legs.

Other than their appearance, lesions rarely cause any additional symptoms. Sebaceous nevus may develop into intralesional tumors, such as basal cell carcinoma or trichoblastoma. However, recent research suggests that this risk is overstated in the medical literature.

The risk of developing life-threatening malignant tumors is almost nonexistent. A sebaceous nude is not necessary for cancer prevention (avoidance of malignant tumors).


Multiple sebaceous lesions and deformities affecting the brain, eyes, and bones are common symptoms of this disorder. Sebaceous nevus is the name given to the skin condition that Schimmelpenning Syndrome patients experience.

It affects the small oil-producing glands on the skin’s surface. The most common type is Schimmelpenning syndrome. Although it is congenital, the sebaceous nude can be present at birth. It may not be detected until childhood or after puberty.

Most often, the scalp and mid-facial region are affected. Affected areas include the trunk, arms, and legs. Sebaceous nuclei are typically yellowed or salmon-colored and have hairless, smooth, and often unattractive patches.

They can appear thickened, warty, or scaly as they grow up (usually around puberty). Large lesions can be found on the scalp. These lesions are often hairless.

Selenium nevi are often seen as an isolated finding. Schimmelpenning syndrome can be used to describe those who have additional symptoms.

Schimmelpenning syndrome can cause neurological abnormalities such as seizures, intellectual impairment, brain malformations, and delays in reaching developmental milestones (developmental delays).

Ocular abnormalities can also be seen in Schimmelpenning Syndrome.

These include a partial lack of tissue (coloboma) from the colored portion (iris) or the membrane lining back of eyes (retina), as well as clouding (opacity), defect of the optic nerve, scarring degeneration or detachment, or loss of the retina.

A benign, yellowish-white, or fatty tumor may form on the outer eyeball (epibulbar lipsodermoid).

The affected individuals may also experience skeletal malformations such as abnormal curvature or dislocation of their hips and deformities in their limbs.

Other cranial defects, such as a prominent forehead (frontal bossing), or abnormally high cheekbones, may also be present.

Other skeletal malformations include bone cysts, underdevelopment, and incomplete formations of bony structures, such as the ankle, foot, and bones of your spinal column (vertebrae).

Schimmelpenning syndrome patients may also experience vitamin D-resistant Rickets. It is a condition that causes leg deformities, pain, and gradual softening of bone structure. Children may have a slower growth rate, which can eventually lead to a shorter stature.

Fractures may occur in those who are affected.

  • The term “epidermal nudus syndrome” was once used to describe Schimmelpenning’s syndrome. 


This type of ENS is characterized by a sebaceous nevus, also known as speckled lentiginous nevus (papular). Schimmelpenning syndrome provides a detailed description of the sebaceous nude.

Speckled lentiginous is characterized by large, dark-brown spots on the skin that are superimposed by numerous darkened (melanocytic) bumps (papules).

Although sebaceous skin nevus can be present at birth, speckled lentiginous spots (papules) may develop later in life. However, in newborns, cafe-au-lait background macules that show a checkerboard pattern are also common.

Additional abnormalities may develop in individuals with phacomatosis.

Neurological abnormalities can include seizures, intellectual impairments, muscle weakness, paralysis of one side (hemiparesis), muscle weakness (hemiparesis), sub-development of one side (hemiatrophy), excessive sweating, and cutaneous dysesthesia.

It is a condition where touching the skin causes a sensation of discomfort.

Skeletal abnormalities include side-to-side curvature (scoliosis), vitamin D-resistant Rickets and bowing deformities in the legs. These conditions are specified by pain in the legs and gradual softening of bone structure.

Children may have a slower growth rate, which can eventually lead to a shorter stature. Fractures may occur in those who are affected.

Other findings include hearing loss in one ear (strabismus), crossed eyes (strabismus), droopy upper eyelids (ptosis), and narrowing the aorta/aortic stenosis.


Nevus comedonicus refers to a skin condition composed of narrowed, widened, and closely-set follicular openings.

In principle, these openings belong to a hair follicle. Still, in nevus comesdonicus, they are plugged with Keratin, a primary structural protein found in the outer skin layer and hair and nails.

These lesions most often occur on the head, but they can also be found on the trunk or limbs. Large cysts containing oil (sebum) may complicate these lesions.

Additional symptoms can be seen in nevus comedonicus syndrome. These different symptoms are usually found on the same side (ipsilaterally) as the skin lesions.

Other symptoms include webbing or webbing in the fingers and toes (syndactyly), abnormal fixation (clinodactyly) of the pinky, so it bends toward the ring finger, preaxial polydactyly), abnormal curvature (scoliosis), and vertebral defects.

Other neurological abnormalities include cognitive deficiencies, bizarre formations of the brain area connecting the two cerebral hemispheres, Corpus Callosum Dysgenesis, and microcephaly.

It is a condition where the infant’s head circumference is smaller than expected based on their age and gender.


This type of ENS has an epidermal nevus, which is covered with long, soft white hairs. The lesion has a wide, band-like appearance. Angora hair nevus syndrome can be associated with seizures, intellectual impairment, and paralysis on one side of the body (hemiparesis).

Other distinctive facial features include a prominent forehead (frontal bossing), malformed ears, and a large tongue (macrostomia).

Ocular abnormalities can also have cataracts, partial absence (coloboma), optic nerve defects, and conditions that influence the structure or work of the pupils (ectopic pupil). Schauder syndrome is also known as Angora hair-nevus syndrome.


Becker nevus can be described by one or more lesions that form a checkerboard pattern. Becker nevus can be described as an overactive hair follicle and pigment cells (melanocytes). 

The affected individuals often have a large, dark brown patch on their skin. It can be seen in the chest, back and shoulder. This skin condition can occur anywhere on the body. 

A Becker nevus develops in puberty and can cause darkening of the skin. Males may also experience excessive hair growth. A Becker nevus can cause males to have asymmetrical growth of their beards.

Individuals with Becker’s nevus syndrome might underdevelop their breasts on the same side as the skin lesions (ipsilateral Breast Hypoplasia). This condition can affect males as well as females. However, it is more common in females.

It is possible to have extra (supernumerary) nipples or abnormally sparse hair below the armpit of the affected side.

Becker nevus syndrome suffers from skeletal and muscle abnormalities, including abnormal curvature (scoliosis), vertebral defects, fused ribs, uneven growth, uneven arms and legs, underdevelopment (odontomaxillary hyperplasia), and a sunken or abnormally large chest (pectus exavatum, pectus cainatum). Underdevelopment of the shoulder muscles on the affected side may be a sign of muscular abnormalities.

Becker nevus syndrome is also known as a pigmented-hairy epidermal syndrome.


Proteus syndrome manifests itself as an overgrowth of tissues throughout the body. It’s not known what causes the disorder. A mosaic pattern is characterized by disproportionate and asymmetrical overgrowth. It means that affected areas are scattered randomly. The complications for affected individuals include:

  • Progressive skeletal malformations and benign and malignant tumors.
  • Malformations in blood vessels (vascular Malformations).
  • Bullous lung disease.
  • Specific skin lesions like keratinocyte Nuvi.

Sometimes, life-threatening conditions may arise from abnormal blood clotting. These include deep vein thrombosis or pulmonary embolism.

Keratinocyte nudus is a linear skin condition that causes an increase in the number of keratinocytes. It is the dominant cell type in the epidermis. It is common in Proteus syndrome patients and affects about 50% of them. The skin usually has a soft, velvety texture. It does not get larger like other Proteus-related skin lesions.

Other cutaneous manifestations of Proteus syndrome include:

  • Telangiectatic, flat, dark red capillary malformations.
  • Underdeveloped skin areas (dermal hypoplasia).
  • Benign growths consist of masses of lymph vessels (lymphangiomas).
  • Connective tissue nevi.

Connective tissue nevi primarily affect the soles and palms. They cause the skin to become thickened and hardened and can form grooves or furrows resembling the fissures in the brain (cerebriform).


Proteus syndrome manifests itself as an overgrowth of tissues throughout the body. It’s not known what causes the disorder. A mosaic pattern is characterized by disproportionate and asymmetrical overgrowth.

It means that affected areas are scattered randomly. The complications for affected individuals include:

  • Progressive skeletal malformations and benign and malignant tumors.
  • Malformations in blood vessels (vascular Malformations).
  • Bullous lung disease.
  • Specific skin lesions like keratinocyte Nuvi.

Sometimes, life-threatening conditions may arise from abnormal blood clotting. These include deep vein thrombosis or pulmonary embolism.

Keratinocyte nudus is a linear skin condition that causes an increase in the number of keratinocytes. It is the dominant cell type in the epidermis. It is seen in approximately 50% of Proteus syndrome patients and has a soft, velvety texture. It does not get larger like other Proteus-related skin lesions.

Other cutaneous manifestations of Proteus syndrome include:

  • Telangiectatic, flat, dark red capillary malformations.
  • Underdeveloped skin areas (dermal hypoplasia).
  • Benign growths consist of masses of lymph vessels (lymphangiomas).
  • Connective tissue nevi.

Connective tissue nevi primarily affect the soles and palms. They cause the skin to become thickened and hardened and can form grooves or furrows resembling the fissures in the brain (cerebriform).

History and Physical

About half of all patients experience NC within a few years of birth. Most patients will develop the lesions by the time they reach ten years of age. The most affected parts are the abdomen, face, neck, upper arms, and chest.

The scalp is a rare site that can be affected. The glans penis and palms are also reported to be involved. The most common presentation is a single cluster of dilated and blocked follicular organs in a honeycomb shape.

Blaschkoid, segmental and linear patterns are also common. Rarely, the lesions are bilateral. There are two types of lesions: non-pyogenic and another that causes cysts, boils, and abscesses.

Nevus comedonicus may occur either in isolation or with other systemic abnormalities such as the central nervous system or skeletal system. Combination subtypes of nevus comedonicus are called a nevus-comedonicus syndrome.


Cowden disease is one of several disorders known as PTEN Hamartoma Syndromes. This group includes a variety of disorders that are caused by mutations in the PTEN gene.

Multiple hamartomas can be seen in these disorders, which can cause them to affect different parts of the body. Type 2 segmental Cowden Syndrome refers to a multisystem condition that results from mutations in the PTEN gene.

It is also associated with a linear Cowden Nevus, which is a type keratinocytic nullus.

Type 2 segmental Cowden disease is very similar to Proteus Syndrome. Some cases have even been mistakenly misdiagnosed with Proteus Syndrome. There are some critical differences in appearance.

The skin lesion of type 2 segmental Cowden disease looks very similar to Proteus syndrome’s keratinocytic nusus. Type 2 segmental Cowden disease is not linked with connective tissue nevi in the palms or soles.

Still, it is connected with focal segmental glomerulosclerosis, a kidney disorder that is not present in Proteus syndrome.


CHILD stands for [c]ongenital h]emidysplasia and [i]chthyosiform leukemia. This disorder is almost exclusively a problem of women and can be present from birth. Hemidysplasia is a condition that affects one side of the body.

The right side is twice as likely to be affected as the left. Inflamed, reddish patches on the skin are covered by yellowish, waxy scales. Additional findings, including neurological, visceral, and skeletal abnormalities, may also be found on the same side as skin lesions.

Skeletal abnormalities can range from mild hypoplasia (hypoplasia) of bones in the hands or feet to complete loss of limbs. Other skeletal malformations may include:

  • Cleft foot or hand.
  • Abnormal curvature (scoliosis) of the spine.
  • Underdevelopment of half the face (facial hypotrophy).
  • Short stature.

Chondrodysplasia punctata is a condition that can be seen on x-rays. This condition causes small, hardened calcium spots to form on the heads or growing portions of long bones (stippled epiphyses).

Several neurological abnormalities can include paralysis or underdevelopment of one hemisphere of the brain, cranial nerve underdevelopment, or absence of specific nerves, paralysis of one side (hemiparesis), and decreased sensation of heat or touch.

Sensorineural hearing loss is caused by the impaired ability of auditory nerves to transmit sensory input to the brain (sensorineural hearing impairment).

Visceral abnormalities can include:

  • Heart disease.
  • Cardiovascular problems.
  • Absence or underdevelopment of a kidney.
  • Unilateral underdevelopment in the lung.

You can find more information by entering “CHILD” into the Rare Disease Database.


This type of ENS is characterized in a keratinocytic epidermal nevus, which is soft and velvety in texture. Seizures, intellectual impairment, brain cell degeneration (cortical atrophy), and underdevelopment in the brain area connecting the two cerebral hemispheres can all be possible.

This disorder has not been associated with skeleton abnormalities. Only a few cases of Garcia-HafnerHapple syndrome have been reported.

It is caused when there are mutations in the fibroblast growth factors receptor 3 (FGFR3) gene. Also known as FGFR3 epidermal nevus Syndrome.


Many other disorders can be considered “in limbo.” These syndromes are only known to exist in a small number of people, and their molecular bases are not yet understood. Researchers are still trying to identify whether these syndromes are distinct types or variations of well-defined ENSs.

These conditions are sometimes referred to as “less well-defined” types of ENSs. These disorders include:

CLOVE syndrome

A shorthand for [c]ongenital, [l]ipomatous, [o]vergrowth and [e]pidermal.nevus. CLOVE syndrome is very similar to Proteus disorder, and many people with this disorder were previously diagnosed with Proteus.

The medical literature states that CLOVE syndrome’s overgrowth of toes is proportionate, non-progressive, and ballooning. Proteus syndrome’s overgrowth is progressive, distorted, and disproportionate.

Researchers believe that CLOVE syndrome could be a variant or distinct disorder of Proteus syndrome. Once the molecular basis for these two disorders has been identified, this question can be answered.

Nevus trichilemmocysticus syndrome

Multiple cysts are found in the hair follicle root sheath (trichilemmal cysts) and can be accompanied by bone lesions.

Didymosis aplasticosebacea

A nevus sebaceous and aplasiacutis congenita can coexist. It is a condition that causes a loss of hair and skin in specific areas, most commonly on the scalp. These lesions tend to be localized and are often found nearby.

SCALP syndrome

An acronym for [s]ebaceous and [c]entral nervous systems malformations.

Gobello syndrome

Gobello syndrome was first reported in 2000 in one person. It involved an organoid nude with velvety skin, excessive hairiness (hypertrichosis), and raised bumps (follicular hyperkeratosis). There were also skelet abnormalities.

Baefverstedt syndrome

Baefverstedt Syndrome was first reported in 1941. It was associated with abnormal horny skin growths linearly.

Also, neurological symptoms like intellectual disability and seizures were noted. The significant horny developments on the neck, face, and underarms became very noticeable.

NEVADA syndrome:
An acronym for Nevus Epidermicus Verrucosus, Angio Dysplasia, and Aneurysms.

Causes of Nevus Comedonicus

Nevus Comedonicus Causes

Many epidermal nevus disorders are believed to be caused by postzygotic mutations, which occur after fertilization. It happens at an early stage in embryonic development. The affected individuals may have both normal cells and cells that carry the abnormal gene (mosaic).

You could call this having two distinct cell lines. Variability in ENS symptoms is partly due to the proportion of abnormal cells and healthy cells. The condition can be fatal if all cells in the body have the same abnormal gene.

Researchers believe this postzygotic mutation is random and occurs sporadically. CHILD syndrome, on the other hand, is inherited as a dominant, male-lethal X-linked dominant trait. It means that it can be passed from a mother to half of her daughters.

Her sons won’t be affected, as male embryos cannot survive without the normal (healthy) X-chromosome.

It is now known what the molecular basis for some types of ENSs is. Mutations in the NSDHL gene are responsible for CHILD syndrome.

Mutations in the PTEN gene are responsible for type 2 segmental Cowden syndrome. Mutations in the FGFR3 genes can cause Garcia-HafnerHapple syndrome.

Researchers should continue to investigate the molecular basis for ENSs to improve their classification.

Populations Affected

Epidermal nevi, including isolated cases, have been present in between 1 and 3 of every 1,000 live births. Although the percentage of epidermal nevi patients with extra-cutaneous malformations is lower, it is still unknown. Individual ENSs are rare and not typical.

Similar Disorders

The symptoms of these diseases might be similar to ENS. Comparative tests may help to determine if there is a differential diagnosis.

Inflammatory liner and verrucous epidermal nudus (ILVEN), a rare skin condition, is characterized by reddening (erythematous), itchy bumps all over the body. These lesions can also be dry and scaly (hyperkeratotic).

ILVEN typically affects one side of the body (unilateral). ILVEN can be present from birth to 6 months after birth. Itching can be very severe. Researchers believe there have been cases in which ILVEN was associated with skeletal or central nervous system abnormalities.

These cases were reported as cases of CHILD syndrome. Contrary to CHILD nevus and ILVEN, the molecular causes of ILVEN are unknown.

Many disorders are characterized by skin lesions, along with additional symptoms like central nervous system abnormalities and skeletal abnormalities. Tuberous sclerosis is one of these disorders.

The McCune-Albright Syndrome, Sturge Weber Syndrome, and neurofibromatosis type 1 and 2 are also included. (For more information, use the exact name of the disorder as the search term in our Rare Disease Database.


An epidermal nevus diagnosis is made upon identifying specific symptoms, detailed patient histories, and a comprehensive clinical evaluation. Sometimes, it may be possible to take a small amount of the affected skin for microscopic examination (biopsy).

To determine the extent and presence of symptoms, additional tests may be necessary. These tests may include a skeletal scan, chest X-rays, and specialized imaging techniques that evaluate the brain.

These imaging techniques include magnetic resonance imaging (MRI) and computerized tomography scanning (CT). It is not clear whether a child suffering from epidermal nevus should be subject to such imaging procedures.

Researchers believe these imaging techniques should be avoided unless there is evidence of central nervous involvement. Molecular testing can now be done in three well-defined ENSs: type 2 segmental Cowden disease and Garcia-Hafner–Happle syndrome.

Standard Therapies – Treatment

Each individual’s symptoms will be treated with ENS. Sometimes, a team of specialists may be required to coordinate treatment.

A child with a condition that affects their eyes may require the coordination of specialists such as pediatric neurologists, dermatologists, and orthopedists.

Many factors influence the treatment and intervention options for individuals suffering from ENS. These include the severity of the disorder, individual’s age, overall health, tolerance to specific medications and procedures, personal preference, and other factors.

Physicians and other healthcare professionals should consult with patients and their parents to determine the best therapeutic options. They must also discuss the risks and benefits, as well as possible side effects and long-term consequences.

Cosmetic surgery may be used to improve your cosmetic appearance. The exact location of an epidermal nude may prevent surgical excision.

Other therapies for ENS vary depending on the particular abnormalities and follow standard guidelines. Epilepsy can be treated with anti-seizure medication, while specific skeletal or ocular malformations can be treated surgically.

There have been many cases in the medical literature where neurosurgery was used to treat epilepsy and ENS.

Individuals with ENSs may also be treated with occupational therapy, remedial education, and physical therapy. Each case should be unique. For affected people and their families, genetic counseling might be beneficial. The supportive treatment of symptoms is also available.

Case Report

A 13-year old boy needed a dermatology opinion for multiple skin-colored raised lesions with black spots in his bilateral armpits. These lesions were present from birth and had been over the bilateral pinna for three to four years.

Except for occasional mucopurulent discharges from the lesions around his armpits, the lesions were not symptomatic. His history of seizure episodes at two months was limited. The cause couldn’t be determined at that time.

He also suffered from delayed milestones in development and lower school performance. The family had no previous history of similar lesions. His mother had lichen platopilaris on the scalp.

Multiple open comedones were found, with a few comedones topped with skin-colored nodules and a few scars that ran along the bilateral axilla. There were also comedones in a linear arrangement that extended from the pubic symphysis to just above the umbilicus.

The first digit of the left hand was affected by flexion and shortening. A regular mucosal examination was performed. Standard evaluation of the ophthalmic and otorhinolaryngeal systems, as well as dental, was done.

For children, the review of physical growth was acceptable for their age. Assessment of intelligence quotient (IQ) revealed mild mental retardation.

Histopathology of the comedonal lesions revealed large epidermal invagination, hyperkeratosis, and focal keratotic plugging. There was also increased basal cell pigmentation. The dermis was not remarkable.

Radiographs of the hands revealed small bilateral pisiform bone structures and an increase in scapholunate joint space for the right hand.

Radiograph of the feet revealed adduction, which involved bilateral metatarsals and medial deviation at the level of bilateral tarsometatarsal joint. Ultrasound of the abdomen revealed a cyst measuring 13 x 11mm in size.

Computerized tomography scans of the spine and head showed a corpus callosum agenesis. There was one interhemispheric cyst.

Biochemical tests revealed vitamin D3 deficiency at 15.69 ng/ml (normal range 30-100). Other biochemical and hematological investigations were also regular.

These findings led to the diagnosis of NC syndrome. The local Tretinoin (0.25%) cream was successful, and the patient experienced partial relief of their comedones.


NC has been associated with extracutaneous manifestations. A term called “nevus comedonicus” has been used.

Other developmental abnormalities that are not cutaneous include skeletal malformations (absent fifth fingers, trichilemmal cysts, and rudimentary tooe, scoliosis), bilateral follicular base cell naevus and Alagille syndrome, CNS disorders (brain dysgenesis (brain dysgenesis), microcephaly (Sturge-Weber syndrome), multiple basal cells carcinoma, multiple basal cells carcinoma, multiple basal cell carcinoma (multilateral oligodontia), bilateral oligodontia (ipsilateral) and bilateral oligodontia (both).

Happy recently used the term “the Epidermal Naevus Syndromes” to refer to at least six disorders, including comedo-naevus disease and extracutaneous manifestations such as verrucous epidermal us and nevus sebaceous.

The NC lesions are morphologically characterized by closely arranged papules with a central, dark, and firm hyperkeratotic plug. Scarring can be significant, and secondary inflammatory changes may include spots that have irregular borders, nodules, or cysts, as well as bumps that have nodules, cysts, and abscesses.

Common areas that are affected include the face, abdomen, chest, chest, and upper arm. A variety of patterns have been described for involvement, including grouped, band-like, or linear Blaschko patterns, as well as extensive unilateral lesions.

The patient, in this case, had widespread participation but not in a specific way. We are not aware of any previous reports of midline lesions in the lower abdomen or involvement of bilateral pinna.

Several CNS abnormalities have been linked to comedo-nevus, including brain dysgenesis, cerebral anomalies, and microcephaly. The literature has not yet reported that our patient had agenesis corpus callosum, an intrahemispheric cyst, and a low IQ.

The most recent report includes polysyndactaly and syndactly and clinodactyly, tridactyl, clinodactyly, and rudimentary. The patient presented with a bilateral metatarsal and medial deviation at tarsometatarsal joints.

The right hand had a small bilateral pisiform as well as increased scapholunate joint space. A pancreatic cyst, which may have involved visceral organs, has not been reported before. However, an “Alagille Syndrome” case has been reported that has both cardiac and liver abnormalities.

If the lesions are large, you can have a surgical excision using tissue expansion. Topical retinoic acids, 12% ammonium lactate, tacalcitol, and tazarotene 0.0.05% with calcipotriene 0.0.005% daily are effective options. For severe acneiform naevi, oral isotretinoin can be used.

This rare case of NC syndrome is unusual and has been reported to have visceral, CNS, and skeletal involvement. The literature is still unfamiliar with the distribution and pattern of NC.


The diagnosis is often clinical. In suspected cases of NC syndrome, it is necessary to perform a thorough evaluation of the central nervous and skeletal systems and the eyes. A skin biopsy reveals the usual dilated follicular openings filled with keratin.

Immunohistochemistry has shown an increase in the proliferating cell nuclear antibody expression, intercellular adhesion molecule-1(ICAM-1), HLA DR, and CD68. An increase in Langerhans cells has been demonstrated by electron microscopy.

The clinical diagnosis is usually precise if there is a history of early-onset and typical morphology.

However, if you have atypical presentations, other conditions that may be differentially diagnosed include segmental and mosaic acneiform disorders, Favre- Racouchot Syndrome (i.e., nodular elastosis accompanied by cysts and comedones), familial dyskeratotic comedones, and chloracne.

It is an autosomal dominantly inherited, rare condition that causes hyperkeratotic, comedonal lesions. Histological examination reveals comedones and associated dyskeratosis.

Dermoscopy is effective in diagnosing nevus comedonicus. Dermoscopy highlights common comedonal lesions. Dermoscopy typically reveals multiple dark brown or barrel-shaped, homogenous areas that are prominent with keratin plugs.

Treatment / Management

It has never been possible to resolve nevus comedonicus quickly. However, aggressive treatment is not recommended since nevus comesdonicus is generally a benign condition.

Most cases are treated for cosmetic reasons or when complications arise, such as abscesses or cyst formation. It may be necessary to have the cosmetic treatment done for post-inflammatory scarring.

There are two options for treatment: topical or systemic retinoids. They can be combined with topical steroids, salicylic acid, or 12% ammonium lactate for their anti-inflammatory effect. In North Carolina, ablative and surgical lasers have been used.

Newer treatments include interleukin-1 alpha inhibitors, FGFR inhibitors, and anti-gamma secretase drugs. A pore strip was used to treat keratin plugs successfully. The treatment of nevus comesdonicus can be done with lasers.

It has been shown that nevus comedonicus lesions can be treated with ultra pulse carbon dioxide and erbium YAG lasers. Recent reports mention the use of a 1450nm diode laser to treat nevus comedonicus.

Sublesional collagen stimulation might decrease epidermal invaginations, which could lead to an improvement of skin texture.

Differential Diagnosis

  • Acne neonatorum
  • Acne vulgaris
  • Angiokeratomas
  • Chloracne, acne conglobata avec extensive comedones
  • Epidermis nevus
  • Epidermoid cyst
  • Family dyskeratotic comedones
  • Favre-Racouchot syndrome
  • Infantile acne
  • Keratosis pilaris
  • Lichen striatus
  • Nevus sebaceous
  • Tuberous sclerosis

Pearls and other Issues

Numerous associations have been reported in conjunction with nevus camedonicus and are part of the nevus comesdonicus syndrome. Nevus comesdonicus syndrome is a condition in which nevus comedonicus presents with additional cutaneous manifestations.

These manifestations typically involve the central nervous system and skeletal system, eyes, teeth, and central nervous system.

Seizure disorders, delayed mental growth, electroencephalogram abnormalities, and microcephaly are significant nervous system abnormalities. Syndactyly, supernumerary numbers, scoliosis, and spina bifida are all examples of skeleton abnormalities.

A cataract is the most common ocular manifestation. Oligodontia is the most common dental abnormality.

Nevus comedonicus is a part of the epidermal-nevus syndrome that covers additional cutaneous manifestations associated with conditions such as nevus comedonicus and verrucous epidermal nevus.

Other syndromes considered part of the epidermal-nevus group include Schimmelpenning Syndrome, Phacomatosis Pigmentokeratotica, and Angora Hair nevus Syndrome.

Hidradenitis can be suppurative, and it is also known as nevus comedonicus. The development of Hidradenitis suppurative-like lesion complicating nevus comesonicus has been described.

Mechanical stress has been suggested as a trigger. Alagille syndrome and spinal dysraphism have been reported as rare systemic associations with nevus camedonicus. 

Improved Healthcare Team Outcomes

If a patient presents with lesions that suggest nevus comesdonicus syndrome, it is crucial to identify any signs and symptoms.

There are no randomized controlled trials that can predict the success of any modality. However, patients should be informed about all options available so they can make an informed decision.

What is the comedo-nevus syndrome?

Comedo-nevus syndrome occurs when comedo is associated with other medical conditions. Like other epidermal conditions, Comedo nevus is not often associated with other abnormalities in the cell of origin or the embryonic ectoderm. These could include:

  • Cataracts
  • Skeletal anomalies include those affecting the spine, fingers, and toes.
  • Developmental delay

What are the treatments for comedo-nevus?

There is no treatment for comedo-nevus. Most lesions are not symptomatic and can be treated for cosmetic reasons. You can see some improvement with topical tretinoin, salicylic acid, or ammonium lactate lotion.

If the lesions are severe, surgery or laser treatment might be an option.

What are the complications of comedo nudus?

Rarely, an inflammatory acne-like condition may occur in a comedo nubus during puberty. These can cause cysts, recurrent infections, scarring, and abscesses.

These conditions should be treated immediately with antibiotics and surgical drainage. The appearance of acne can be improved by topical or oral treatment.

Things to be aware of in the history

Half of the cases occur at birth. The remainder arises before puberty, particularly in the first ten years of life. Very few cases of sporadic manifestations have been reported later in life, most often following irritation or trauma to the affected area.

It is Koebner’s isometric response in patients who have had nevus comedonicus elsewhere and Wolf’s isotopic reaction in patients who do not have nevus comedonicus. Herpes zoster and lichen planus have been reported as primary lesions.

Physical examination reveals characteristic findings.

The most common location for the neck, face, neck, upper arms, and abdomen lesions. Each group contains a small number of markedly dilated, follicular ovaries filled with dark keratin. Blaschko’s lines may show lesions in a linear arrangement.

Multiple linear lesions may sometimes be visible that end at the midline. However, not all cases can be considered unilateral.

The size and extent of lesions can vary depending on whether they are small, large, or needy. Some lesions can involve volar surfaces. If this occurs, eccrine structures may be involved clinically as well as histologically.

The scalp and male and female reproductive mucus membranes are fewer commonplaces of involvement.

The sizes of the lesions vary from 0.5 to 5mm in diameter and are tightly grouped. Figure 1: Each lesion appears as a darkly colored comedone. Some lesions can appear verrucous, mainly if they are located near prominences like the elbows and knees.

Secondary inflammation can lead to cicatrix development. The skin near lesions may appear hypopigmented. The lesions can become more severe during puberty and menstruation.

Some authors have divided patients into two groups because the severity of Nevus Comedonicus can vary. The first group has no comedo-like symptoms. Large cysts, scarring, and recurrent abscesses can also be seen in the second group.

The lesions in the first group are cosmetic and not a problem. In the second, scarring or suppuration can be a significant concern.

Diagnostic studies: Expected results

Histology shows an accumulation of dilated hair follicles with orthokeratotic plugging and absent or very rudimentary follicles. Many layers of keratinocytes line the walls of the strands. They are also atrophic and have sparse stratumgranulosum.

The walls may also show epithelial budding. In the beginning, lesions might have small hair shafts or small sebaceous cells. Glabrous skin is usually free of eccrine or apocrine glands.

Confirmation of diagnosis

Other epidermal nevi can be used to diagnose nevus comedonicus.

These include infantile acne, Jadassohn’s nevus sebaceous (with three phases of evolution depending on the stage of differentiation), Favre-Racouchot (open and close comedones on skin that has been chemically exposed), Darier’s disease (skin-colored papules or yellow-brown with a smooth verrucous appearance, often located in the seborrheic region and are associated with mucus membrane changes) and severe form (s), which is prone to disfigurement), and extensive comedones.

Skin biopsy can rule out most of them.

Who are at risk for this disease?

Nevus comedonicus, which accounts for less than 1% of epidermal cancers, is very rare. Only 200 cases have been reported yet. A retrospective review of 417.511 Mexican pediatric patients revealed that 443 children had epidermal nevi.

Five patients had nevus comedonicus. Both males and females got equally affected. There is no predisposition to a particular race.

What causes the disease?

Nevus comedonicus seems to be a subset of epidermal-nevus. Both can be explained by somatic mutation. Familial lesions can indicate a more complicated etiopathogenesis in some cases.

A somatic mutation in fibroblast-growth factor-2 receptor (FGFR-2) has been identified in Nevus comedonicus. This gene has been linked to several other diseases, such as Apert’s syndrome and chondrodysplasia.

Systemic Implications and Complications

Nevus comedonicus is often associated with other entities. Patients with extensive involvement are more likely to have these. Some lessons can also be associated with more profound abnormalities in the same places in bone and muscle.

If associated lesions are cancerous, such as basal cells cancers, it is essential to monitor the patient to detect and treat such malignancies closely. There has never been any malignant degeneration reported in lesions of the nevus comedonicus.

These patients are often referred to as “nevus comedonicus syndrome” because they have any above combination. This syndrome should also be considered in conjunction with epidermal nevus disorders.

Basal cell carcinomas and basal carcinoma syndromes are reported as associated entities.

There are many treatment options.



  • Topical retinoid cream (tretinoin 0.1%),
  • Topical retinoid cream (0.1%) combined with topical corticosteroid lotion (mometasone furoate).
  • Topical 12% ammonium Lactate Lotion
  • Topical tacalcitol
  • Topical tazarotene
  • Topical calcipotriene


  • Antibiotics for systemic use
  • Intralesional steroids


Surgical intervention – The Best Therapeutic Approach for This Disease

First, confirm the diagnosis. A laboratory test should not be performed unless other involvement is suspected or apparent based on clinical or other findings. To ensure the diagnosis, a skin biopsy should be performed.

If there are secondary infections or complications, localized lesions can be treated cosmetically. It has never been reported that the nevus comedonicus spontaneously receded. Assistive lesions should be treated as soon as possible.

Topical retinoid cream (tretinoin 0.1%) has been shown to improve lesions. This agent accelerates epidermal exfoliation, which results in the expulsion of keratin plugs and comedonal lesions.

You can combine it with topical corticosteroid cream (mometasone furoate). The effectiveness of a topical 12% ammonium-lactate lotion, applied once per day, has been shown to reduce the appearance of comedones.

Topical tacalcitol is also reported to be helpful. With great success, topical calcipotriene cream 0.005% and topical tazarotene 0.05 cream were combined.

Cystic disease with more severe lesions may need systemic antibiotics (tetracycline 500mg twice daily, doxycycline 100mg twice daily, orally) and intralesional steroids (5-10mg/cc). There has been a mixed success with different antibiotic treatments.

Cyst formation can be prevented by systemic administration of isotretinoin (0.5-1.0mg/kg). It would be best to consider the iPledge regulations, which restrict this drug due to its teratogenic side effects and other side effects.

For larger lesions, surgery may be necessary. The manual extraction of comedones may speed up the process.

Patient Management

If there are no associated conditions (see the unusual scenarios section), and with proper local management, the prognosis can be excellent.

Unusual Clinical Scenarios to be Considered in Patient Management

One case was reported by a patient suffering from nevus comedonicus, a condition that is complicated by lichen striatus or linear morphea.

One case of hidradenitis suppurativa has been reported. It was possibly associated with nevus camedonicus.

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