Mycosis Fungoides

/in , /by

Mycosis Fungoides (MF) is a form of non-Hodgkin lymphoma that is considered the most common type of primary cutaneous T-cell lymphoma (CTCL).MF is a neoplasia of malignant monoclonal T lymphocytes that generally invades the skin and causes cutaneous signs and symptoms.It is characterized clinically during early stages as erythematous scaly patches and plaques, or during advanced stages as tumors or erythroderma, with lymph node and/or visceral involvement.And histologically presents as an epidermotropic infiltrate of small-medium sized CD4+ T lymphocytes with cerebriform nuclei. Mycosis Fungoides (MF) is the most prevalent cutaneous T-cell lymphoma, accounting for 50-65% of cases. Typically seen in men [1.6-2:1] ratio and appears in late adulthood with 55-60 years as a median age of diagnosis. Even so, MF is a rare and uncommon condition, the incidence of MF in the United States is approximately 0.3-1.02 new cases per 100.000/year. MF follows an indolent clinical course over years, with an estimated 5-year survival rate of 87% and a median survival of 11.4 years. Also patients who present with involvement of lymph nodes or viscera have a median survival of <1.5%.
MF natural history is a classical slow progression from patches to plaques to tumors stage typically on unexposed areas such as the trunk, buttocks and thighs. Due to MF manifesting a variety of clinical and pathological presentations, atypical presentations of MF may be difficult to diagnose. Within this broad spectrum of clinical presentations, the World Health Organization (WHO) classified MF into 3 main variants or subtypes; folliculotropic MF, pagetoid reticulosis, and granulomatous slack skin.

Patch stage:
● Poorly defined, irregular, finely scaling, red patches of variable size often with atrophic (thin, wrinkled) skin
● Occurs mainly on sun-protected sites particularly the lower trunk, thighs and, in women, the breasts
● Often asymptomatic
● Hypopigmented variant: pale, finely scaly patches without atrophy in children and Fitzpatrick skin types
IV-VI
● Poikiloderma atrophicans vasculare is atrophic patch stage MF presenting with skin thinning, pigment
changes, and dilation of capillaries (telangiectasia)
Plaque stage:
● Well-demarcated annular or arciform itchy thickened lesions
● Color often red, violaceous, or brown, sometimes scaly
Tumor stage:
● Large irregular lumps (>1 cm) developing from plaques
● Deep red to violaceous color, often shiny surface

Diagnosis:
The diagnosis of mycosis fungoides requires careful clinicopathological correlation. Dermoscopy can help to distinguish MF from inflammatory dermatosis.

Treatment:
Mycosis fungoides is treatable, not curable. There are no globally accepted treatment guidelines. Treatment should be guided by the patient’s wishes, stage of disease, availability of options, and local expertise.

Topical treatment:
● Topical steroids
● Topical chemotherapy eg, nitrogen mustard, carmustine
● Topical bexarotene
Procedural treatment:
● Phototherapy — PUVA, narrowband UVB
● Radiotherapy and whole-body total skin electron beam therapy
● Extracorporeal photopheresis
Systemic treatment:
● Chemotherapy — mycosis fungoides is relatively chemoresistant
● Immunotherapy — interferon-alpha
● Oral retinoids and rexinoids (eg, bexarotene)
Only brentuximab vedotin (for CD30+ MF) and allogeneic haematopoietic stem cell transplant alter the natural history of the disease.

 

Written by: Khalid Nagshabandi, medical student

Reference: DermNet

Poikiloderma of Civatte

/in , /by

 

 

Poikiloderma of civatte is a chronic benign skin condition. It is characterised by a triad of skin atrophy, hyper\hypopigmentation and telangiectasia. It is most commonly seen in middle aged fair-skinned people, especially postmenopausal ladies.

Etiology:

The main etiology behind this skin condition is unknown. However, there are some factors that contribute to its occurrence. Among these factors, sun exposure is thought to be the most significant. Other factors include: Hormonal changes (low estrogen levels), genetic predisposition and being repeatedly exposed to photosensitizing components of cosmetics and perfumes.

Clinical presentation:

Clinically, poikiloderma presents as a rash that affects mainly the sun-exposed areas, such as the neck and the lateral aspects of the cheeks, usually sparing the shaded area under the chin. It is characterised by confluent reddish-brown patches with atrophy of the involved area. Poikiloderma is mostly asymptomatic, but patients could present with mild burning, itching, or episodes of flushing.

Treatment:

Poikiloderma is a chronic, irreversible skin condition. It responds poorly to available treatments. Most importantly, the patient should be educated regarding the importance of avoiding sun exposure, and should be encouraged to apply sunscreen. They should also avoid all perfumes on or near the affected site, including scented soaps. Treatment options that could help improve the condition include: 

  • Hydroquinone
  • Hydrocortisone cream 
  • Topical retinoids can be of benefit if used for about a year.
  • Alpha hydroxy-acids may help reduce pigmentation.
  • Pulsed dye laser treatment and intense pulsed light (IPL) used to reduce the telangiectasia and pigmentation
  • Fractional nonablative laser treatment could improve the vascular, pigmented and textural components of poikiloderma of Civatte. 

 

Written by: Rema Aldihan, medical intern.

Reference: 

dermnetnz.org

 

Clinical Presentation of Sézary Syndrome

/in , /by

 

Sézary syndrome (SS) is a leukemic type of cutaneous T cell lymphoma (CTCL) in which the peripheral blood contains a large number of circulating malignant (Sézary) cells. SS is assumed to be made up of mature epidermotropic skin homing CD4+ T cells or central memory T cells. The goal of this discussion is to go over the clinical characteristics of SS.

 

Skin lesions — SS patients typically have extensive erythema that is finely scaled, indurated, or resembles livedo reticularis. The severity of erythema and the amount of body surface area (BSA) involved may fluctuate, but at some point during the disease’s course, the skin involvement must cover >80% of the BSA to meet the SS definition from The International Society for Cutaneous Lymphoma (ISCL), European Organization for Research and Treatment of Cancer (EORTC), and United States Cutaneous Lymphoma Consortium (USCLC).

The following is an overview of the skin lesions:

 

  • Keratosis pilaris-like lesions –Follicular involvement may be characterized by inflamed follicular-based papules or scale.
  • Alopecia – Alopecia is common and manifests as a loss of hair density all over the scalp and body, or as patches of alopecia.
  • Ectropion – Because of the tautness and induration in the skin, an outward tilting of the lower eyelid with increased exposure of the ocular surface and sensitive mucous membranes of the inner lid might develop, which may be related with disruption of normal tear drainage pattern.
  • Keratoderma – Keratoderma, or thicker keratin retention on the palms and soles, is a typical feature that can help distinguish SS from other causes of erythroderma, but it can also make the diagnosis between SS and pityriasis rubra pilaris difficult.
  • Hypertrophic nails – Because of the involvement of the posterior nail fold, the nails may become hypertrophic.
  • Erosions and superinfection –Patients are frequently colonized with Staphylococcus aureus, and persistent scratching causes erosions and superinfection.
  • Focal areas of scaling – Tinea corporis is prevalent, and if scaly areas are present, a potassium hydroxide preparation should be conducted.
  • Lichenification – Long-term disease, chronic pruritus, and scratching can cause diffuse lichenification, which is defined as thickening skin with enlarged skin lines. Fissures are a regular occurrence.

 

Lymphadenopathy — Peripheral lymphadenopathy is common, and a biopsy usually reveals either dermatopathic changes or lymphoma-like alterations, both of which are linked to the underlying cutaneous lymphoma.

 

Viscera — The prevalence of visceral involvement in SS patients is unknown. Because bone marrow examination is not frequently conducted, unless in the case of unexplained hematologic abnormalities, the prevalence of bone marrow involvement is unknown.

 

Pruritus — The most common and debilitating symptom of SS sufferers is pruritus. The length and depth of erythema, as well as the degree of blood involvement, are not always connected to the degree of pruritus. Pruritus can make sleep problems, anxiety, and depression worse.

 

 

Written by: Lama Altamimi, medical intern.

Reference: UptToDate

https://www.uptodate.com/contents/clinical-presentation-pathologic-features-and-diagnosis-of-sezary-syndrome?search=%20S%C3%A9zary%20syndrome&source=search_result&selectedTitle=1~58&usage_type=default&display_rank=1#H449464055

Dermatofibroma

/in , /by

Dermatofibroma, aka cutaneous fibrous histiocytoma, is a benign fibrous nodule composed of fibroblasts and histiocytes. It mainly occurs on the lower extremities. Dermatofibromas are mostly seen in females —although some histological variants are more common among males. Moreover, developing multiple dermatofibromas is usually associated with immunosuppression and autoimmune diseases.

Etiology:

It is unclear whether dermatofibroma arises as a result of a reactive process or a true neoplasm. There still isn’t a well-established cause for this condition. However, minor traumas, such as insect bites and injections are believed to trigger the development of these nodules. 

Clinical presentation:

Dermatofibroma characteristically presents as a firm papule/nodule. The size of the nodule varies, it ranges from 5 mm to about 1.5 cm in diameter. The nodule is usually tethered to the skin above it —the skin dimples when pinching the lesion— and mobile over subcutaneous tissue beneath it. The color of the nodule is usually pink or light brown in fair-skinned individuals, and dark brown or black in those with darker skin tones; some nodules may appear paler in the center. Furthermore, dermatofibromas are mainly asymptomatic, but could sometimes be painful, tender, or itchy. 

Diagnosis:

The diagnosis is made clinically, and is supported by dermoscopy. The most common finding on dermoscopy is a central white area surrounded by a faint pigmented network. A diagnostic skin biopsy is only required if there are atypical features; whether clinically or on dermoscopy. These features include a recent enlargement, ulceration, or asymmetrical structures and colors on dermoscopy. 

Treatment:

These lesions are benign and harmless, and therefore don’t require any intervention. However, it can be removed surgically if the patient is concerned. Patients should be informed that recurrence is common, as the lesion usually extend beyond the clinical margins. Other modalities, such as cryotherapy and laser rarely showed complete success.

Written by: Rema Aldihan, medical intern.

Reference: 

dermnetnz.org

Sunscreen

/in , /by

Ultraviolet radiation exposure causes deleterious effects on the skin, contributing to skin aging, cancer and photosensitivity. To prevent its impact, sunscreen application is imperative in protecting the skin against these harmful radiation. 

 

The sun emits three main UV radiation at different wavelengths:

  • Ultraviolet A (UVA) comprises 95% of the UV radiation. Its intensity is consistent throughout the day and from season to another. 
  • Ultraviolet B (UVB) makes up the remaining 5% UV radiation detected on the earth’s surface. The intensity of UVB is highest during summer and from 10 a.m to 4 p.m during the day. 
  • Ultraviolet C (UVC) is absorbed by earth’s atmosphere and is of little concern.  



Sunscreen works by absorbing or scattering UV radiation, primarily UVA and UVB, minimizing the effect on the skin. There are two categories of sunscreen agents with different mechanisms: Chemical (organic) and physical (inorganic). 

 

Chemical (organic) filters 

It acts by absorbing high energy light. They are further classified into UVA filters and UVB filters but companies use a combination of both filters to yield higher sun protection factor (SPF), stability and broad-spectrum absorption. In addition, organic filters have outstanding safety and aesthetic properties with minimal phototoxicity, photosensitivity and staining on skin. 

 

Physical (inorganic) filters

Inorganic filters reflect and scatter light. Most common agents are metal oxides titanium dioxide and zinc oxide, it’s chemically inert and protects against the full UV spectrum. However the inorganic leaves a whitecast that raises cosmetic concerns. 

 

There are other measures for protection that can be implemented alongside sunscreen application, like choosing long sleeves and trousers, wearing broad hats and adequately applying/reapplying sunscreen. 



The use of sunscreen is beneficial in mitigating the risks of skin cancer and disorders from UV radiation. Both chemical and physical sunscreens generally have an excellent safety profile, but chemical sunscreens are systemically absorbed. There are no harms, but further studies are required to confirm that.

 

Written by: Naif Alalshaikh, medical student.

 

References: 

“Topical Sunscreen Agents.” Sunscreens, Sunblocks | DermNet NZ, https://dermnetnz.org/topics/topical-sunscreen-agents. 

Gasparro, Francis P., et al. “A Review of Sunscreen Safety and Efficacy.” Photochemistry and Photobiology, vol. 68, no. 3, 1998, pp. 243–256., https://doi.org/10.1111/j.1751-1097.1998.tb09677.x. 

 

Ngoc, et al. “Recent Trends of Sunscreen Cosmetic: An Update Review.” Cosmetics, vol. 6, no. 4, 2019, p. 64., https://doi.org/10.3390/cosmetics6040064. 


Female Pattern Hair Loss

/in , /by

Female pattern hair loss (FPHL) is a type of nonscarring hair loss that affects mostly adult women. The disorder is marked by the loss of terminal hairs in the frontal and vertex regions of the scalp, resulting in an apparent loss of hair density. In contrast to many cases of androgenetic alopecia in males (male pattern hair loss), the loss of terminal hairs in afflicted areas is generally partial, and the frontal hairline is frequently preserved. This article will go through the pathophysiology, clinical symptoms, and diagnosis of FPHL.

The phrase “androgenetic alopecia” was once the most popular word used to describe the emergence of common, progressive hair loss on the frontal scalp and/or vertex of the scalp in both men and women. The terms “andro” and “genetic” denoted a hormonal etiology and a component of inheritance to the clinical presentation, respectively. As more research on hair loss was published throughout time, the phrase “female pattern hair loss” evolved to be the favored word for this kind of hair loss in women. This updated name reflects the absence of evidence to support a hormonal impact in all cases of the illness and helps to separate the distinct clinical aspects of this process in women vs males.

Hair loss across the frontal scalp and vertex of the scalp in FPHL is caused by a gradual decrease in the ratio of terminal hairs to shorter, thinner vellus hairs in the afflicted regions, a process known as follicular shrinkage. The duration of the anagen (growth) phase of hair follicles is reduced from a few years to weeks or months as a result of this process. Although hormonal variables and genetic predisposition are thought to have a role in FPHL, the mechanism by which these factors cause FPHL is unknown. The majority of women with FPHL do not have high amounts of androgens in their blood.

FPHL is a non-scarring type of hair loss that manifests as a gradual decrease in the density of terminal scalp hairs in a specific pattern. The principal areas of involvement are the frontal scalp and the vertex of the scalp. Although widespread involvement does occur from time to time, the occipital scalp is typically avoided.

The trend of hair loss differs from woman to woman. Frontal scalp thinning is the most apparent characteristic in some individuals, resulting in a “Christmas-tree” pattern when the hair is separated at the midline, but diffuse center thinning is the most prominent feature in others. Although women commonly have modest bitemporal thinning, the frontal hairline is typically preserved. It’s uncommon to observe a combination pattern that looks like male androgenetic alopecia (frontotemporal recession and vertex loss).

FPHL is not characterized by scarring, inflammation, or scaling. If these characteristics are present in a patient with hair loss, another scalp condition may be present alongside FPHL or may be the only cause of the clinical symptoms. FPHL is generally diagnosed clinically, depending on the patient’s medical history and physical examination. The presence of a reduction in hair density in the typical distribution, as well as an increasing incidence of miniaturized hairs, suggests the diagnosis. Biopsies of the skin are seldom done, although they might be useful when the diagnosis is unclear or a concurrent scalp condition is suspected. Several types of non scarring and scarring hair loss are included in the differential diagnosis of FPHL. Telogen effluvium, central centrifugal cicatricial alopecia, and traction alopecia are among of the more frequent illnesses having FPHL-like characteristics.

 

Written by:  Lama Altamimi, medical intern.

 

Reference:

UptToDate

 

Monkeypox

/in , /by

 

Monkeypox virus belongs to the orthopoxvirus genus. Orthopoxvirus is a genus of viruses in the family Poxviridae –the same family as cowpox and smallpox. Monkeypox is endemic in several African countries. Since 13 May 2022, several cases of monkeypox have been reported outside the endemic countries. Surprisingly, there hasn’t been any established travel links to endemic areas in those cases. Moreover, the current outbreak of monkeypox is evolving, as the number of cases is changing rapidly.

Transmission: 

Monkeypox virus is transmitted from person to person through contact with body fluids or lesion material, contact with fomites, or exposure to respiratory secretions. Fortunately, monkeypox is not easily transmitted.

Diagnosis: 

The diagnosis of monkeypox virus requires a 2-step process to be done on the specimen. First is the OPX DNA testing to confirm the presence of orthopox virus –CDC is currently treating all orthopox virus cases as monkeypox until proven otherwise. The second step is a PCR test (only available at CDC) which confirms monkeypox virus. 

Clinical features: 

Monkeypox initially begins as a flu-like illness with fever and lymphadenopathy –lymphadenopathy is a key clinical feature that helps differentiate monkeypox from smallpox. Then a centrifugal rash erupts; rash starts as macules>papules>vesicles>pustules>scabs. Lesions usually appears simultaneously and evolve together at any part of the body, eg. pustules on the face and vesicles on the arm. Lesions are well circumscribed, deep seated and are occasionally umbilicated. Lesions could be pruritic or painful. 

Treatment: 

 All specimens reported outside of endemic countries, to date, are from the West African clade of monkeypox. This variant is associated with milder illness, therefore, supportive treatment is usually sufficient. Nevertheless, there are 2 CDC-approved therapies to be used in severe cases of monkeypox: tecovirimat and Vaccinia Immune Globulin Intravenous (VIGIV). 

 

Written by: Rema Aldihan, Medical student.

References: 

www.cdc.gov 

https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON385

 

Basal Cell Carcinoma

/in , /by

Basal cell carcinoma is by far the most common cutaneous malignancy. Basal cell carcinoma is a tumor that grows slowly and rarely metastasizes.  BCC is more common among males living in geographic locations with greater UV exposure. Furthermore, previous history of SCC or BCC is the most common predictor of BCC development. 

Etiology: 

It is believed that BCC originates from pluripotent cells in the basal layer of the epidermis or the pilosebaceous unit. This might explain the rare occurrence of BCC in the hand despite it being a frequently sun exposed area. As the dorsum of the hand lacks the presence of sebaceous structures. 

Moreover, it is well-established that the single most important risk factor for developing BCC is UV light exposure –particularly UVB light. Lighter skin phototypes, ionizing radiation exposure, immunosuppression, and genetic predisposition are all associated with increased risk of BCC. 

Clinical Features: 

BCC presents as a slowly growing skin colored/pink plaque or nodule, that could bleed or ulcerate spontaneously. Occasionally BCC could metastasise to lymph nodes. 

 BCC subtypes: 

1.Nodular BCC:

It presents as a pearly nodule with a smooth surface, rolled edges, and may have central depression, ulceration, and telangiectasia . Cystic variant is soft, with jelly-like consistency. 

2. Superficial BCC:

It presents as a scaly, irregular plaque with thin rolled edges. It may present with multiple micro-erosions.

3.Morphoeic BCC:

It presents as a waxy, scar-like plaque with irregular borders. It may present with deep extensions, sometimes infiltrating cutaneous nerves. 

4. Basosquamous carcinoma:

It is a mix between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). it has an infiltrative growth pattern and could potentially be more aggressive than other subtypes of BCC

5. Pigmented BCC:

The rarest type of BCC, which comprises 6% of total BCC. This type can occasionally mimic melanoma. 

Diagnosis and Treatment: 

A histological diagnosis of BCC is a must, either through a biopsy or following excision. Furthermore, there are multiple treatment modalities used for BCC, which include both surgical and non-surgical therapies. Surgical treatment include: excision biopsy, mohs micrographically controlled excision, and superficial skin surgery.  Non-surgical modalities include: cryotherapy, Imiquimod cream, radiotherapy, photodynamic therapy and Fluorouracil cream.

 

Written by: Rema Aldihan, medical student. 

References: 

  1. https://www.ncbi.nlm.nih.gov/books/NBK482439/
  2. dermnet

Melanoma

/in , /by

What is melanoma?

Melanoma is a serious type of skin cancer that affects melanocytes, which are pigment-producing cells that give skin its color. Melanoma is more likely to spread and invade other organs in the body, making it more dangerous and malignant than other forms of skin cancers.

How does melanoma develop?

Transformation of melanocytes to melanoma requires a complex interaction of various factors. The cells undergo histological changes and ultimately progress to malignant melanoma. The first change that occurs is the development of benign nevi, comprising mainly of neval melanocytes, a variant of normal melanocytes but slightly larger. Nevi can remain dormant and static for decades but with certain endogenous and exogenous factors, like genetic mutations in CDKN2A and BRAF, it can progress to malignancy.

Who gets melanoma and what are the risk factors?

The strongest risk factors for melanoma are UV light exposure, family history of melanoma, previous melanoma and sun sensitivity. It affects mainly white population with fair skin, and the highest reported rate are in Australia and New Zealand. Melanoma occurs most commonly between the age of 40 to 60 years, however there has been an increase in incidence in young adults around the age of 20. The occurrence is extremely rare in children. 

What are the clinical features of melanoma?

Melanocytes are found throughout the body, thereby melanoma can be present anywhere on the body, not necessarily in areas with a lot of sun exposure. It begins as a mole or freckle, frequently on the back in males and lower extremities in females, but clinical presentation varies depending on the type.

Melanoma subtypes

There are four main types of melanoma that are associated with the same growth pattern, i.e horizontal, and anatomical site predilection.

Superficial spreading melanoma

Most common type, associated with intermittent UV exposure. It can appear on an existing mole or a new mole. It is likely found on the torso in men and legs of women.

Lentigo malinga

Occurs in chronically sun-exposed individuals and it is easily detected by simple visual inspection.

Nodular melanoma

This type is rapid growing and aggressive.

Acral and mucosal melanoma

Most common type of melanoma in Asian and African population. This type is not associated with UV radiation. 

Melanoma comes in many shapes, sizes and colors. Clinical diagnosis is primarily based on patient history total-body skin examination. Early detection and prevention are key in curing and preventing melanoma; applying sunscreen and UV radiation avoidance (staying indoor, avoiding tanning bed) may prevent the development of melanoma.

Written by: Naif Alalshaikh, Medical student. 

References 

  1. “Melanoma.” DermNet
  2. Miller, Arlo J., and Author AffiliationsFrom the Dermatopathology Unit. “Melanoma: Nejm.” New England Journal of Medicine, 28 Sept. 2006,
  3. “Melanoma.” The Skin Cancer Foundation, 28 Apr. 2022,
  4. Melanoma – Edisciplinas.usp.br.

Pachyonychia congenita

/in , /by

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

/in , /by


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

/in , /by

 

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