Atlas of Diseases

  Lentigo maligna is a type of skin cancer that usually appears as a slowly growing, flat, brown or black patch on sun-exposed areas, often on the face, especially in older adults. It's considered an early stage of melanoma, a more serious form of skin cancer, and it is sometimes referred to as melanoma in situ . The condition typically develops in people who have had significant sun exposure over many years. Key Features of Lentigo Maligna: Appearance : It presents as a patch that may be irregularly shaped, with varied colors such as brown, black, or tan. The edges may be blurred. Growth : Lentigo maligna grows slowly over several years. Age Group : It's most common in people over the age of 50, especially in those with fair skin. Location : Most commonly found on sun-exposed areas like the face, neck, and arms. Risk : While lentigo maligna itself is non-invasive (confined to the epidermis), it can eventually progress into lentigo maligna melanoma, which is invasive and requi...

  Granuloma annulare is a skin condition characterized by the formation of ring-shaped, red or skin-colored bumps or lesions, typically around the edges of a circular pattern. It is generally considered a benign, self-limiting condition, meaning it usually resolves on its own without treatment. However, it can sometimes persist for months or even years. Key Facts: Appearance : Raised, ring-like lesions with a smooth surface, often red or purple at the edge and normal or slightly pale in the center. Common Locations : The arms, legs, and torso are the most frequent sites, though it can appear anywhere on the body. Causes : The exact cause is unknown, but it is believed to involve an inflammatory response, often triggered by factors like: Immune system dysfunction Trauma or injury to the skin Certain medications (e.g., vaccinations, or drugs for tuberculosis) Diabetes (it is sometimes associated with underlying conditions such as diabetes or thyroid disease) Infections, like viral or...

  Darier Disease (Keratosis Follicularis) is a rare genetic skin disorder that primarily affects the skin, often appearing during adolescence. It is inherited in an autosomal dominant pattern, meaning only one copy of the mutated gene is needed for the disease to manifest. Symptoms: Skin Lesions : The most common feature is the appearance of greasy, scaly, and often reddish-brown bumps or plaques on the skin. These lesions typically appear on the chest, back, scalp, and forehead. Nail Changes : Nails may show abnormalities like thickening, pitting, and longitudinal ridges. Oral Lesions : Some individuals develop warts or lesions in the mouth. Pruritus : Itching is a common complaint associated with the lesions. Causes: Darier disease is caused by mutations in the ATP2A2 gene , which is responsible for regulating calcium levels in cells. This leads to a defect in cell adhesion, causing skin cells to separate and form lesions. Diagnosis: Clinical examination : Based on appearance an...

  Pyogenic granuloma is a type of benign (non-cancerous) growth that typically appears on the skin or mucous membranes. Despite the name, it is not caused by infection ("pyogenic" refers to pus-producing), and it's not a true granuloma (which refers to a specific type of immune response). Instead, pyogenic granulomas are often associated with rapid tissue growth and are made up of small blood vessels, which gives them their characteristic red or purple appearance. Key Characteristics: Appearance : They often look like a small, raised, reddish bump with a smooth surface. Sometimes they may bleed easily due to their rich blood supply. Common Locations : They can occur anywhere but are most common on the hands, face, and mouth (especially around the gums). Causes : The exact cause is unknown, but they can occur due to: Trauma or injury : A minor injury might trigger the formation of these growths. Hormonal changes : Pregnancy and puberty can sometimes be associated with the ...

  Bullous Pemphigoid is a rare, autoimmune blistering skin disorder primarily affecting older adults. In this condition, the body's immune system mistakenly attacks the skin's basement membrane (the layer that connects the epidermis, or outer layer, to the dermis, the deeper skin layer). This leads to the formation of large, fluid-filled blisters. Key Characteristics: Blisters : The most noticeable symptom is the development of large, tense blisters on the skin, often on areas like the abdomen, groin, and upper thighs. These blisters may be itchy and can break open, leading to open sores. Itching : Intense itching is a common early symptom before the blisters appear. Skin Inflammation : Red, inflamed skin is often seen before blisters develop. Lesions : The blisters are typically large and filled with clear fluid. They usually appear in clusters. Causes: Bullous pemphigoid is believed to be caused by the immune system producing antibodies that attack certain proteins in the sk...