A solitary erythematous papule on the nose

Epistaxis, or nosebleeds, occurs when small, swollen blood vessels in the nasal mucous membrane rupture. Typically, the anterior septum is the primary site of occurrence.
Etiology
Possible causes of this condition include high blood pressure, trauma, low humidity, upper respiratory tract infections, allergies, foreign bodies, nasal inhalation of corticosteroids or illicit drugs, excessive use of decongestant nasal sprays, facial or nasal surgery, anatomic malformation, tumors, or systemic...

The nose is composed of an observable exterior segment (external nose) and an internal segment within the skull known as the nasal cavity (internal nose). The external nose, visible on the face, consists of a framework of bone and hyaline cartilage enveloped in skin and muscle and lined with a mucous membrane. This structure is supported by the frontal bone, nasal bones, and maxillary bone and is supplemented by a cartilaginous framework comprising the septal nasal cartilage, lateral nasal...

Dermis
The dermis might be considered the "core" of the integumentary system, as distinct from the epidermis and hypodermis. It contains blood and lymph vessels, nerves, and other structures, such as hair follicles and sweat glands. The dermis is made of two layers of connective tissue that comprise an interconnected mesh of elastin and collagenous fibers, produced by fibroblasts.
Papillary Layer
The papillary layer is made of loose, areolar connective tissue, which means the collagen...

Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...

The color of the skin is influenced by a number of pigments, including melanin, carotene, and hemoglobin. Recall that melanin is produced by cells called melanocytes, which are found scattered throughout the stratum basale of the epidermis. The melanin is transferred to the keratinocytes via melanosomes.
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...

The first thing a clinician sees is the skin, so the examination of the skin should be part of any thorough physical examination. Most skin disorders are relatively benign, but a few, including melanomas, can be fatal if untreated. A couple of the more noticeable disorders, albinism and vitiligo, affect the appearance of the skin and its accessory organs.
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...