Pachyonychia congenita

Pachyonychia congenita is a rare inherited disorder of keratinization that primarily affects the nails and skin. Affected people develop thickened skin on the soles and palms, white patches on the tongue and mouth, and bumps around the elbow and knees. 

What is the cause of pachyonychia congenita?

The disorder is caused by a genetic mutation but features vary depending on the affected gene. Five keratin specific genes are involved: K6a, K6b, K6c, K16, and K17. These genes provide instructions for the synthesis of keratin; a protein found in the skin, hair and nails. The frequent pathogenic variant is in K6a.

 

Pachyonychia congenita is inherited in an autosomal dominant manner. It is found in ethnic groups and occurence is equal in both sexes.

What are the clinical features of pachyonychia congenita?

Clinical features vary based on the involved keratin gene and specific genetic mutation but it is usually characterized by:

  • Calloused palms and soles with plantar pain in most of the patients. Sometimes underlying blisters are present 
  • Thickened nails often with brown discoloration. 
  • Certain types of sebaceous gland cysts, steatocystoma and pilosebaceous, are found in PC patients.
  • White patches affecting the tongue and inside of the mouth. 

Diagnosis

Diagnosis is based on the presence of clinical signs and appearance. There is a clinical diagnostic criteria that includes the triad of the commonest features of toenail thickening, plantar keratoderma and plantar pain of pachyonychia congenita (PC) In addition, detection of a mutation in only one of the aforementioned genes confirms PC diagnosis. 

What is the treatment of pachyonychia congenita?

Limiting certain physical activity like walking, maintaining ideal body weight, and wearing ventilated shoes with moisture-wicking socks. Regular trimming of nails and calluses when necessary, and if needed, appropriate treatment of infections. Topical therapy to remove hyperkeratosis includes emollients and retinoids.

Pachyonychia congenita is an extremely rare disease that does affect the lifespan of the affected person, however it can negatively impact the quality of life. The pain and appearance of this condition can interfere with day-to-day activities and social life. 

Written by: Naif Alalshaikh, Medical student.

References

  1. “Pachyonychia Congenita.” Pachyonychia Congenita | DermNet NZ, https://dermnetnz.org/topics/pachyonychia-congenita
  2. “Pachyonychia Congenita.” Genetic and Rare Diseases Information Center, U.S. Department of Health and Human Services, https://rarediseases.info.nih.gov/diseases/10753/pachyonychia-congenita. 
  3.  PMC, Europe. Europe PMC, https://europepmc.org/article/nbk/nbk1280#free-full-text

Xeroderma pigmentosum


Xeroderma pigmentosum (XP) is a rare autosomal recessive DNA repair disorder characterized by enhanced UVR sensitivity, early pigmentary alterations, UVR-induced skin and mucous membrane malignancies, and, in some cases, progressive dementia. Moritz Kaposi, a dermatologist, first reported XP in 1874, coining the word “xeroderma” to describe the dry or xerotic skin quality of his four XP patients. While early research suggested that UVR played a role in the disease’s development, it wasn’t until 1968 that the sickness was linked to faulty DNA repair in cultured skin fibroblasts. XP subtypes or “complementation groups” were discovered as a result of this; XP-variant is the only form of XP with intact DNA excision repair capacity.

Males and females are equally affected by Xeroderma pigmentosum (XP), which is found worldwide but has a wide range of occurrence. The estimated incidence in the United States and Western Europe is one per million live births, according to retrospective investigations. Incidences as high as 15 to 20 per million in Libya and 10 to 50 per million in Japan have been reported in other research. Due to more frequent consanguineous marriages, incidences in Northern African and Western Asian nations such as Libya, Tunisia, Morocco, and Pakistan may be greater. Consanguinity, on the other hand, isn’t thought to account for all of the global differences.

Early-onset pigmentary skin alterations, early development of skin malignancies (typically in the first decade of life), and ocular signs, such as photophobia, conspicuous conjunctival injection, and severe keratitis, are all common features across all xeroderma pigmentosum (XP) groups. Neurologic diseases, such as sensorineural hearing loss and gradual cognitive impairment, are seen in certain patients.

Skin cancer — Squamous cell cancer (SCC), basal cell carcinoma (BCC), and melanoma all occur more frequently in XP than in the general population, and at a younger age. The odds of nonmelanoma skin cancer (NMSC) and melanoma were shown to be 10,000-fold and 2000-fold greater in a 40-year National Institutes of Health follow-up study of 106 XP patients, respectively, than in the general population.

Skin cancer is the most prevalent type of cancer connected with XP, although multiple studies suggest that XP patients may be at an increased risk of other malignancies as well. In 142 consanguineous French families of North African origin with an XPC mutation, an increased frequency of hematologic malignancies, such as myelodysplastic syndrome, acute myeloid leukemia, and acute lymphoblastic leukemia, was observed. Colorectal cancer susceptibility has been linked to XPG single nucleotide polymorphisms, particularly among Asians. In nonsmoking Chinese female patients, XPD polymorphisms were found to be associated with the risk of non-small cell lung cancer.

A child with acute sun sensitivity with minimum exposure, early and prominent freckling (before the age of two years), and skin cancer within the first decade of life should be suspected of having xeroderma pigmentosum (XP). Photophobia with conspicuous conjunctival injection, severe keratitis, sensorineural hearing loss, and increasing cognitive impairment are other clinical symptoms that point to the diagnosis. Clinical symptoms, a family history consistent with autosomal recessive inheritance, and/or confirmatory genetic tests are used to make the diagnosis.

Dermatologists, ophthalmologists, oral surgeons, geneticists, and neurologists are part of a multidisciplinary team that treats individuals with xeroderma pigmentosum (XP). The pillars of treatment are strict sun protection and avoidance, diligent clinical follow-up with regular skin and eye examinations, and appropriate and early treatments of any premalignant or malignant skin lesions.

Patients with xeroderma pigmentosum (XP) die most often from metastatic skin cancer, followed by neurodegeneration. Patients with neurodegeneration die at a significantly younger age than patients without neurodegeneration, with a median age of 29 versus 37 years.

 

Written by: Lama Altamimi, medical intern.

Reference: https://www.uptodate.com/contents/xeroderma-pigmentosum?search=xeroderma%20pigmentosum&topicRef=3004&source=see_link

 

 

Unilateral Laterothoracic Exanthem

 

What is Unilateral laterothoracic exanthem?

It is an uncommon condition characterized by a unilateral, periflexural rash that starts from the axilla or groin and can spread to the face, genitalia or hands. The lesions are red, raised and surrounded by white halos. 

Who is affected by it?

The condition affects mostly children of the age of 2-5 years, but there has been an increase in the number of cases among adults. 

What is the cause?

The cause of unilateral laterothoracic exanthem (ULE) is unknown but exposure to certain viruses are implicated in (UTLE). Epstein Barr virus and parvovirus B19 are commonly associated with UTLE, and most recently with COVID-19. 

How is ULE diagnosed?

Diagnosis is based on clinical presentation and skin biopsy in some cases. If the patient is asymptomatic, no treatment is needed. Emollients and topical steroids are used to relieve the itching. 

 

ULE resolves without treatment. It can be mistaken for other cutaneous conditions such as contact dermatitis, scabies and a slew of other conditions

 

Written by: Naif Alalshaikh, medical student.

References: 

Glick LR, Fogel AL, Ramachandran S, Barakat LA. Unilateral laterothoracic exanthem in association with coronavirus disease 2019. JAAD Case Reports. 2020 Sep;6(9):900.

Chuh AA, Chan HH. Unilateral mediothoracic exanthem: a variant of unilateral laterothoracic exanthem. CUTIS-NEW YORK-. 2006 Jan 1;77(1):29.

Adams SP. Dermacase. Unilateral laterothoracic exanthem. Canadian Family Physician. 1997 Aug;43:1355.

dermnetnz.org

 

Papillon-Lefèvre Syndrome

Papillon-Lefèvre syndrome (PLS) is a rare genetic condition that affects children between the ages of one and five. It is inherited in an autosomal recessive manner. It results from alterations of the CTSC gene; which regulates the production of cathepsin C enzyme. PLS is characterized by the appearance of hyperkeratotic patches on the palms and soles, as well as severe inflammation and deterioration of the structures that surround and support the teeth (periodontium). 

Clinical Presentation: 

Oral features: 

Severe gingivostomatitis and periodontitis are the most common symptoms of PLS. In patients suffering from PLS, deciduous teeth erupt in the expected order, with normal structure and shape, at the appropriate ages. However, gingiva becomes inflamed during the first year after the eruption of deciduous teeth, followed by fast periodontal deterioration evidenced by visible reddish and swollen gingiva, severe bone resorption, and deep periodontal pockets out of which pus exudates in response to minimal pressure. Due of the hypermobility of the teeth, mastication is quite uncomfortable in those patients. A foul smelling mouth odor is usually present. Around the age of 4-5 years, the child’s deciduous teeth fall out prematurely, and the child becomes entirely edentulous, with gingiva returning to its normal status. Nevertheless, with the eruption of permanent or successor teeth, periodontitis occur again. By early adolescence, the majority of the successor teeth will fall out.

Cutaneous features: 

PLS is marked by the appearance of dry, scaly patches of skin (hyperkeratosis) in children between the ages of one and five; it is manifested simultaneously with oral manifestations. These patches most commonly affect the palmar aspect of the hands and the plantar aspect of the feet –although they can also affect the knees and elbows. The skin of those who are affected can be abnormally red and thick, but it can also vary in texture and color. Skin lesions may worsen in cold weather, making walking extremely difficult. 

Management: 

A multidisciplinary approach involving a team of a dermatologist, a pediatrician and a dentist is crucial for patients with PLS. Moreover, emollients and salicylic acid are used to treat the cutaneous manifestations of PLS; topical steroids may be used to enhance their effectiveness. Oral retinoids including acitretin, etretinate, and isotretinoin have been shown to help with both oral and cutaneous PLS lesions.

Written by: Rema Aldihan, Medical Student.

References: 

rarediseases.org

www.ncbi.nlm.nih.gov/pmc/articles/PMC4507741/

Cutaneous leiomyoma

Cutaneous leiomyomas, also known as piloleiomyomas, are benign uncommon smooth muscle tumors that arise from the arrector pili muscle, which is in charge of hair follicle piloerection. Piloerection, or “goose bumps,” is an involuntary mechanism that can occur as a result of cold exposure or a range of emotional states (eg, fear, pleasure).

Hereditary leiomyomatosis and renal cell cancer is an autosomal dominant cancer condition in which cutaneous leiomyomas can occur randomly or in large numbers. The discovery in 2001 of a link between cutaneous leiomyomas, uterine leiomyomas in women, and an aggressive form of renal cell cancer (RCC) emphasizes the importance of accurate dermatologic diagnosis of CL so that patients and at-risk relatives can receive appropriate cancer screening and counseling.

The co-occurrence of uterine leiomyoma and cutaneous leiomyomas was known under several different eponyms prior to the discovery of the association with renal cell cancer (RCC), including Reed syndrome, multiple cutaneous leiomyomas (MCL), and multiple cutaneous and uterine leiomyomatosis syndrome (MCUL1), leading to potential confusion regarding the associated cancer risk. All of these diseases are now known to be related with mutations in the fumarate hydratase gene (FH)

Clinical Manifestations:

Cutaneous leiomyomas are hard, red or reddish-brown nodules that range in size from 3 mm to 1 cm in diameter. Small lesions may appear as thin, slightly elevated papules, whereas bigger nodules may be exophytic and protrude significantly from adjacent lesions. Isolated leiomyomas of the scrotum (dartos muscle), vulva, or nipple have been reported on rare occasions (areolar smooth muscle). Leiomyomas arising from genital skin, unlike piloleiomyoma, are frequently asymptomatic.

Diagnosis:

Clinical diagnosis — When a patient presents with single or several papules or nodules on the trunk or extremities that are often painful to the touch, cutaneous leiomyoma is suspected. A history of episodic pain in response to cold, rubbing, or pressure is common.

Multiple cutaneous leiomyomas should be considered a red flag for inherited leiomyomatosis and renal cell carcinoma (HLRCC).

Biopsy — To confirm the diagnosis of cutaneous leiomyoma, a skin biopsy is required. The skin tissue obtained from a punch biopsy is usually sufficient for pathologic diagnosis.

Genetic testing — The presence of a germline mutation in the FH gene is required for a conclusive diagnosis of HLRCC. Individuals who appear with clinical signs of HLRCC or who have a family history of HLRCC should be offered genetic testing.

Management:

Dermatologists, gynecologists, and urologic oncologists collaborate to treat patients with hereditary leiomyomatosis and renal cell carcinoma (HLRCC). The following are important aspects of management:

  • In individuals with many painful cutaneous leiomyomas, pain management is important.
  • Consultation with a gynecologist on a regular basis to check for the presence and severity of uterine leiomyomas.
  • Renal cancer surveillance

Patients with a family history of HLRCC should seek genetic counseling to identify asymptomatic at-risk relatives and begin surveillance for renal cell carcinoma (RCC) at a young age.

Treatment of cutaneous leiomyomas:

Isolated lesions — For cutaneous leiomyomas that are isolated or few in number, surgical excision is the therapy of choice. Because intralesional injection often exacerbates pain, local anesthetic should be used with caution.

Complete excision of segmental or other substantial areas of cutaneous leiomyoma involvement in the HLRCC situation may result in extensive surgical scars that are visually undesirable. Furthermore, patients with numerous lesions have been observed to have a 50% recurrence rate.

Multiple clustered or widespread lesions — Several ablative, topical, or systemic treatments have been tried for individuals with multiple symptomatic cutaneous leiomyomas for whom surgery is not a viable choice due to location, burden of disease, or cosmetic consequence.

However, there is only a single case report and one tiny randomized trial to back up their effectiveness.

Prognosis:

Fumarate hydratase (FH) mutation carriers have a 15 to 20% lifetime risk of developing kidney cancer. Between the ages of 10 and 20, FH carriers have a 1 to 2% chance of developing renal cell carcinoma (RCC), which increases as they get older. Even though the initial tumor is modest, these kidney cancers are aggressive, with rapid nodal and distant dissemination.

Written by: Lama Altamimi, medical intern

Reference: UpToDate

https://www.uptodate.com/contents/hereditary-leiomyomatosis-and-renal-cell-cancer-hlrcc?search=xeroderma%20pigmentosum&topicRef=3004&source=see_link#H56466874

Hemangioma and PHACES Syndrome:


Hemangioma is the most common benign vascular tumor of infancy. It is more common among baby girls than boys (3:1). Low birth-weight, advanced maternal age, multiple pregnancy (twins and triplets), placenta previa and preeclampsia are all risk factors for developing infantile hemangioma. It is believed that the expression of GLUT1 protein in utero is the placental origin for infantile hemangioma. 

Most hemangiomas don’t occur at birth but appear within the first two weeks of life, most commonly on the head and neck area. It usually starts off as a red spot resembling a scratch, but instead of fading away, it gradually grows. Most infantile hemangiomas grow very rapidly in the first 3 months, they tend to have a growth arrest by 5 months of age, and recede over the next couple of years.  Hemangiomas could be superficial or deep; superficial hemangioma appear bright red, while deep hemangioma appear bluish-purple in color. The majority of hemangiomas are focal, but could occasionally present as segmental or multifocal. 

Hemangioma could arise on its own or as a part of PHACES Syndrome, which was first described by Dr. Ilona Freidan in 1996. It is a syndrome that includes infantile haemangiomas and malformation of eyes, heart, arteries and brain. The acronym PHACES stands for: Posterior fossa abnormalities, Hemangioma, Arterial abnormalities, Cardiac abnormalities, Eye and Endocrine abnormalities and Sternal clefts. 

 

Segmental haemangioma is more likely to be associated with PHACES syndrome when compared to focal haemangiomas. Moreover, the specific site of the segment affected by hemangioma can indicate the likely problem associated with it. For example, frontotemporal segments are associated with brain malformations, and mandibular segments are associated with cardiac anomalies and airway hemangiomas. 

Infants with hemangiomas larger than 24 cm on the face or scalp should undergo investigations to screen them for PHACES syndrome. Investigations include MRI, MRA, CTA, Eye examinations, ear examinations, audiometric testing, echocardiogram and U/S for blood vessels. 

The management of PHACES syndrome is tailored to each child depending on the involved organs. Careful evaluation of major blood vessels in the brain and heart should be undertaken prior to initiating propranolol. 

 

Written by: Rema Aldihan, medical student.

 

References:

https://www.ccakids.org/assets/syndromebk_hemangiomas.pdf

 

Epidermolysis bullosa (EB)

Epidermolysis bullosa (EB) is a group of genetic disorders characterized by skin fragility. Patients with EB are prone to developing blisters on their skin and mucous membranes. These blisters can appear anywhere, but most commonly on areas subjected to repeated minor traumas. In some subtypes, blisters may appear in internal organs leading to various debilitating complications. Unlike epidermolysis bullosa acquisita, which is autoimmune in origin, EB arises from a genetic defect in the molecules responsible for adhesion. Loss of adhesion is the main cause of blistering in EB.

 

There are four known types of Epidermolysis bullosa; EB simplex, Junctional EB, Dystrophic EB, and Kindler syndrome. Within each type there are various subtypes, and severity varies from mild to severe in each EB type. 

 

Epidermolysis bullosa simplex: 

EBS is usually inherited in an autosomal dominant manner, i.e. an affected parent could transmit it to half of his/her children. The genetic mutations in EBS occur in genes responsible for Keratin 4, Keratin 15, or plectin. The blistering in this type occurs in the epidermis layer, hence EBS doesn’t usually cause scarring. Blistering commonly involves areas that are subjected to repeated friction, such as the hands and feet. Moreover, EBS may be localized to the hands and feet or it may present in a generalized distribution, with relatively mild internal organ involvement.

 

Junctional epidermolysis bullosa: 

JEB is inherited in an autosomal recessive manner, ie. the abnormal gene must be inherited from both parents, and 1 in 4 of their children could be affected. It involves mutations in the genes for Laminin 332 (formerly known as Laminin5), plectin, and a6b4 integrin. These are essential components of the junction between the epidermis and dermis. Blistering in this type occurs in the lamina Lucida within the basement membrane. JEB causes generalized blistering of the skin and mucous membranes with varying severity. It is usually life-threatening, the mortality rate is high— especially the generalized severe form of JEB. 

 

Dystrophic epidermolysis bullosa:

DEB is classified into two major subtypes based on the mode of inheritance— Dominant DEB (DDEB) which is dominantly inherited, and recessive DEB (RDEB) which is recessively inherited. Both subtypes are caused by a mutation in the Type VII collagen gene. Blisters are formed in lamina densa within the basement membrane zone and the upper dermis. DEB causes generalized blistering of the skin and mucous membranes which leaves behind scarring and can cause severe disfigurement.

 

Kindler syndrome: 

Kindler Syndrome is inherited in an autosomal recessive manner. It results from mutations in the FERMT1 gene; which is responsible for the production of Kindlin-1 protein. This protein plays an important role in the proliferation, cell-matrix adhesion, and migration of cells. In Kindler syndrome, there is a mixed pattern of blistering on multiple levels within and underneath the basement membrane. Blistering usually begins in early infancy, especially on the dorsal aspect of hands and feet. Patients with Kindler syndrome are at a high risk of developing squamous cell carcinoma.

 

Written by: Reema Aldihan, medical student

References :

https://rarediseases.org/rare-diseases/epidermolysis-bullosa/

https://medlineplus.gov/genetics/condition/kindler-syndrome/

https://dermnetnz.org

 

Ichthyosis Vulgaris

 

 

The most prevalent of the ichthyoses is ichthyosis vulgaris, a heterogeneous collection of inherited keratinization disorders characterized by extensive scaling of the skin of different severity. Pathogenic mutations in the filaggrin gene (FLG), which encodes profilaggrin, a key component of the keratohyalin granules in the epidermis’ granular layer, cause IV. Individuals who inherit a single mutant allele are substantially less seriously impacted than those who acquire homozygous or compound heterozygous mutations, indicating that the IV inheritance pattern is semidominant.

Clinical presentation:
The condition appears as widespread, dry skin with thin, white or gray scales on the extensor extremities and trunk in infancy or early childhood. Associated characteristics include hyperlinear palms and keratosis pilaris. Extensor extremities and the trunk are usually afflicted, with intertriginous (e.g., axillary, antecubital, and popliteal) skin remaining unaffected. It’s unusual for the sides of the neck to be involved. Scaling has a range of severity. Individuals who have only one mutant allele (heterozygotes) have a modest phenotype that can be mistaken for simple dry skin, whereas individuals who have mutations in both alleles (homozygous or compound heterozygotes) have a more obvious condition. The severity of the condition varies dramatically by season, improving in warm and bright weather with high ambient humidity and deteriorating in dry and cold conditions.

Diagnosis:
The clinical diagnosis of ichthyosis vulgaris (IV) is based on the patient’s personal and family history, as well as clinical findings on physical examination. Although individuals with homozygote or compound heterozygote variations of the filaggrin gene (FLG) who have a more severe phenotype may find it easier to diagnose, heterozygotes, who normally have a very mild symptom, may find it more difficult.

The following clinical signs and symptoms point to an IV diagnosis:

  • Scale: Fine, white or gray, central attachment; extensor surface of extremities and trunk involved; folds spared.
  • Palmar hyperlinearity: Major fissures are exaggerated, minor fissures are increased, and lines on the thenar eminence are accentuated.
  • Keratosis pilaris.

The following are examples of personal and family history that support the diagnosis of IV:

  • Symptoms appear shortly after birth, and are most common in early childhood.
  • Warm weather and emollients make a difference.
  • With age, there may be an improvement.
  • Atopic eczema or other atopic illnesses are linked.
  • Occurrence in the family

A skin sample with hematoxylin and eosin staining that shows a marked decrease or absence of the granular layer in the epidermis can assist confirm the diagnosis of IV. Biopsies are best performed on the extensor side of the arm or the shin. Electron microscopy can confirm keratohyalin granule abnormalities, despite the fact that it is rarely utilized for routine skin diagnosis.

Genetic testing – Although not regularly done in clinical practice, genetic testing demonstrating pathogenic mutations in the FLG gene offers the definite diagnosis of IV. Although variants differ within populations, and identification of “private” variants is difficult and may be overlooked unless Sanger sequencing or an equivalently comprehensive examination of the complete gene is performed, common population relationships may be beneficial for screening.

Treatment:
The goal of ichthyosis vulgaris (IV) treatment is to remove scales, reduce skin dryness, and improve the appearance of the skin. It entails regular bathing and the use of moisturizers and keratolytics.

1- Bathing – People with dry skin, especially those with IV, are frequently advised to take long baths to help remove scale. Although only a few studies back it up, this advice is basic sense and has lasted the test of time. The value of bath additives such as oils and sodium bicarbonate is debatable. After bathing, moisturizers should be applied, whether or not soaps or synthetic detergents were used.

2- Emollients and moisturizers — The mainstay of IV treatment is frequent and generous application of emollients and moisturizers. Moisturizers keep the skin hydrated and smooth. Humectants like glycerin, occlusives like petrolatum, emollients like cetyl alcohol, keratolytics like urea and alpha-hydroxy acids, and other ingredients are included. Occlusives, which are water insoluble but have a lower molecular weight than occlusives, prevent water loss; emollients, which are water insoluble but have a lower molecular weight than occlusives, smooth the skin; and keratolytics help remove scale.

3- In the therapy of IV, topical retinoids, steroids, calcipotriene, and systemic retinoids are not recommended. The treatment of atopic dermatitis is covered in another article.

Prognosis:
Individuals with ichthyosis vulgaris (IV) live normal lives with no known shortening of life expectancy, but they must cope with the daily treatment of scaling skin disease, which is frequently associated with moderate to severe atopic dermatitis. In the ichthyoses, quality-of-life studies have focused on the more severe conditions, but none have addressed IV.

The majority of people with ichthyosis want to learn more about their condition and how to best treat it. They usually have a better understanding of what works for their skin once they have this information, and they rarely seek medical help until they have a problem. This is especially true in IV, where eczema causes the most therapeutic problems and consequences.

Written by: Lama Altamimi, Medical intern.

Reference:

UptToDate

 

 

Id Reaction

 

Id reaction or autosensitization dermatitis is an immunological reaction that occurs in response to a distant localized inflammatory/infectious skin condition. It most commonly occurs in response to a local fungal infection occurring elsewhere. The classical example of this reaction is tinea pedis leading to an eczematous eruption on the patient’s hand.

Etiology:

The precise pathophysiology of this condition is not yet fully understood. It is postulated that this reaction happens as a secondary immunological reaction induced by circulating antibodies or activated T cells directed against the microbial agents. Infections that could lead to an Id reaction include fungal, viral, bacterial and arthropod infestations. Furthermore, inflammatory conditions such as chronic venous eczema, acute contact dermatitis, and discoid eczema could also cause an Id reaction.

Clinical presentation: 

Id reaction exhibit a wide variety of presentations, including localized or widespread vesicular lesions, maculopapular eruptions, erythema nodosum, erythema multiforme, erythema annulare centrifugum, Sweet’s syndrome, guttate psoriasis, and autoimmune bullous disease. Although any of these presentations could occur as a reaction to any inflammatory/infectious skin condition, there are some common patterns observed. For example, localized vesicular lesions are usually seen with tinea pedis; erythema nodosum is seen more with bacterial, subcutaneous, and deep fungal infections; and erythema multiforme with herpetic infections. Moreover, regardless of the cause, this reaction most commonly occurs on the medial and lateral aspects of the fingers. Less frequently, this reaction could happen on the chest or arms as well.

Treatment: 

Treating the underlying infection (primary source of infection) is usually sufficient to resolve the issue. For instance, treating tinea pedis (athlete’s foot) with a topical antifungal agent should lead to a prompt resolution of the vesicular lesions on the fingers. However, oral or topical steroids may sometimes be needed.

Written by: Rema Aldihan, Medical student.

References: 

Ilkit M, Durdu M, Karakaş M. Cutaneous id reactions: a comprehensive review of clinical manifestations, epidemiology, etiology, and management. Critical reviews in microbiology. 2012 Aug 1;38(3):191-202.

dermnetnz.org

How to Avoid Rosacea Triggers

 

Rosacea is a skin disease that causes erythema to form across the nose and cheeks. In addition to medical therapy, rosacea patients can improve their remission by identifying and avoiding common environmental factors that may trigger flare-ups or aggravate their conditions. Below are the lists on how to prevent the rosacea to flare-ups:

 sun protection:

sun exposure is the most common trigger, and should be avoided by applying a broad-spectrum sunscreen with an SPF of 30 or higher. In addition, it is better to use fragrance-free sunscreen containing zinc oxide and titanium dioxide because they are less likely to cause skin irritation. Moreover, wearing a hat when exposed the sun is essential to protect the face and neck. 

 Avoid stress:

Emotional stress accounts for 79% of rosacea flare-ups; try to do activities that relieve your stress, such as yoga classes, and joining support groups. Minimize eating spicy food/ food and beverages that are high in temperature; one can drink iced coffee or tea instead, or let hot beverages warm a bit.

 Review medications:

There are some medications known to trigger rosacea, like antihypertensives and vitamins, that has to be reviewed by the treating physician.

 Reduce Exercising in a hot climate:

Exercising will increase the body temperature, and that will worsen the condition. This can be avoided by doing less intense exercise and doing it indoors.

 Makeup precautions:

Using a mild, fragrance-free emollient to the skin before applying makeup can help prevent flares. Avoiding waterproof makeup or heavy foundations is vital to avoid flare-ups.

Select specific skin and hair care products:

avoid using products that contain these products — menthol, camphor, or sodium lauryl sulfate as it commonly worsens the rosacea.

 Protect the face from cold wind

 

Written by: Dr. Nouf Aljomah, dermatology resident

References:

American Academy of dermatology

https://www.nhs.uk/

 

Steven-Johnson Syndrome (SJS) and Toxic epidermal necrolysis (TEN)

Introduction:
SJS and TEN are rare, acute, and potentially fatal reactions affecting the skin and the mucous membrane. The evidence suggests that both SJS and TEN result from a defect in detoxifying drug metabolites, inducing immune responses. Moreover, Interaction between drug metabolites and immune cells causes extensive keratinocyte cell death via apoptosis, leading to dermo-epidermal junction separation, causing detachment of the skin and the mucous membrane.

Etiology:
Medications are the leading offending cause of SJS and TEN, where they have been reported in more than 95% of TEN cases. The most common drugs that cause SJS and TEN are allopurinol, antibiotics (e.g. Sulfonamides), nonsteroidal anti-inflammatory drugs, and anticonvulsants (e.g. Phenytoin). SJS and TEN usually happen between 7-21 days after initiation of causative medications, while some medications (e.g. Anticonvulsants) may take up to 2 months to develop SJS and TEN. However, they occasionally occur as a result of infection or immunization.

Classification:
Steven-Johnson Syndrome: 10% body surface area (BSA) detachment
Overlapping SJS/TEN: 10-30% of the BSA detachment
Toxic epidermal necrolysis:  30% of the BSA detachment

Clinical Presentation:
Initially, fever, conjunctivitis, and body aches can precede mucocutaneous presentation by 1-3 days. The cutaneous manifestation usually starts as sudden, tender/painful erythema of the skin. It first appears on the trunk, spreading to the neck, face, and proximal upper extremities. Skin lesions in SJS and TEN can present as purpuric macules, diffuse erythema, targetoid lesion, and/or flaccid blisters. In addition, Mucosal erythema and erosions are present in more than 90% of patients.

Diagnosis:
SJS and TEN are diagnosed by history and clinical presentation with a histopathologic evaluation of skin lesion.

Management:
To have optimal management of SJS and TEN requires making the diagnosis as soon as possible, immediate identification and cessation of the offending drug, and supportive care. Furthermore, SJS and TEN need a multidisciplinary team that includes dermatology, internal medicine, ophthalmology, and plastic surgery.

  • Supportive management includes admission to intensive care or burns unit, daily wound and eye care, paraffin sheet, and high protein soft diet. In addition to, fluid replacement, mucosal hydration, and pain management should be initiated once a diagnosis is made.
  • Choices of medical treatment in SJS and TEN includes:
    1. Cyclosporine (3-5 m/kg/day for 7-14 days)
    2. IVIG (3-4 g/kg total dose over 3–4 days)
    3. Single-dose etanercept 50 mg subcutaneous or infliximab IV once
    4. Plasmapheresis
    5. The use of steroids is controversial, only indicated within the first 72 hours.

Mortality and prognosis:
The course of SJS and TEN is unpredictable. Therefore, the mortality should be assessed and recorded at admission within 72 hours using SCORTEN score, a prognostic scoring system for predicting mortality in SJS and TEN. Furthermore, the leading causes of mortality in SJS and TEN are sepsis, renal failure, and/or massive water loss with electrolytes disturbance. Finally, complete skin healing of detached skin usually takes 3-4 weeks.

Written by: Dr. Ahmed Almutairi, dermatology resident.

Reference:

Bolognia 4th edition

Cutaneous Squamous Cell Carcinoma

 

Cutaneous squamous cell carcinoma (cSCC) is a malignant skin tumor that arises from the epidermal keratinocytes. They can develop on any cutaneous surface, including the head, neck, trunk, extremities, oral mucosa, periungual skin, and anogenital areas. In individuals with fair-skin, it mainly arises in sun-exposed areas. On the other hand, in individuals with darker skin tones, it primarily develops in non-sun exposed areas, such as the lower legs, anogenital region, and areas of chronic inflammation or scarring. The latter accounts for 20-40% of cSCC in black patients.

More than 90% of cases of SCC are associated with countless DNA mutations in various somatic genes. For example, mutations in the p53 tumor suppressor gene are caused by exposure to ultraviolet radiation (UV), especially UVB (signature 7). Other signature mutations are related to cigarette smoking, aging, immunosuppression.

 

Clinical features:

Cutaneous SCC presents with a wide variety of cutaneous lesions, including papules, plaques, or nodules, that can be smooth, hyperkeratotic, firm/indurated (more with well-differentiated), or ulcerated, fleshy, granulomatous, +/- area of hemorrhage or necrosis (poorly differentiated). Cutaneous SCC in situ (Bowen’s disease) mainly presents as an erythematous, well-demarcated, scaly patch or plaque located in sun-exposed areas. Lesions of invasive cSCC are often asymptomatic but may be painful or pruritic or have local neurologic symptoms (e.g., numbness, stinging, burning, paresthesias, paralysis, or visual changes).

 

Diagnosis: 

SCC is diagnosed based on clinical features and confirmed pathologically by diagnostic biopsy or following excision. Staging investigations may also be carried out in high-risk SCC to determine whether it has spread to lymph nodes or elsewhere.

Cutaneous SCC is catigorized as low-risk or high-risk, depending on the chance of tumor recurrence and metastasis. Characteristics of high-risk SCC are shown in this Figure. Metastatic SCC is found in regional lymph nodes (80%), lungs, liver, brain, bones, and skin.

 

Management:

Cutaneous SCC is almost always treated surgically, and most cases are excised with a 3–10 mm margin of normal tissue around the tumor. Reconstruction using a flap or skin graft may be needed to repair the defect. Other methods of removal include:

  • Shave, curettage, and electrocautery: for low-risk tumors on trunk and limbs
  • Aggressive cryotherapy: for tiny, thin, low-risk tumors
  • Mohs micrographic surgery: for large facial tumors with indistinct margins or recurrent tumors
  • Radiotherapy: for an inoperable tumor, patients unsuitable for surgery, or as adjuvant

 

For advanced/or metastatic SCC?

Locally advanced primary, recurrent or metastatic SCC requires multidisciplinary team (MDT) consultation. Usually, a combination of treatments is used, including surgery, radiotherapy, cemiplimab, and experimental targeted therapy using epidermal growth factor receptor (EGFR) inhibitors.

 

Written By: Dr. Iman Nazer,  Dermatology resident.

References:

Uptodate 

Dermnetnz.org

BAD guidelines