The initial trauma causing the infection is often forgotten or not noticed. The infection builds at the site over a period of years, and a small red papule (skin elevation) appears. The lesion is usually not painful, with few, if any symptoms. Patients rarely seek medical care at this point.

Several complications may occur. Usually, the infection slowly spreads to the surrounding tissue while still remaining localized to the area around the original wound. However, sometimes the fungi may spread through the blood vessels or lymph vessels, producing metastatic lesions at distant sites. Another possibility is secondary infection with bacteria. This may lead to lymph stasis (obstruction of the lymph vessels) and elephantiasis. The nodules may become ulcerated, or multiple nodules may grow and coalesce, affecting a large area of a limb.

Mycoses are classified according to the tissue levels initially colonized.

Chromoblastomycosis (also known as chromomycosis, cladosporiosis, Fonseca's disease, Pedroso's disease, phaeosporotrichosis, or verrucous dermatitis) is a long-term fungal infection of the skin and subcutaneous tissue (a chronic subcutaneous mycosis). The infection occurs most commonly in tropical or subtropical climates, often in rural areas. It can be caused by many different types of fungi which become implanted under the skin, often by thorns or splinters. Chromoblastomycosis spreads very slowly; it is rarely fatal and usually has a good prognosis, but it can be very difficult to cure. The several treatment options include medication and surgery.

Superficial mycoses are limited to the outermost layers of the skin and hair.

An example of such a fungal infection is "Tinea versicolor", a fungus infection that commonly affects the skin of young people, especially the chest, back, and upper arms and legs. "Tinea versicolor" is caused by a fungus that lives in the skin of some adults. It does not usually affect the face. This fungus produces spots that are either lighter than the skin or a reddish brown. This fungus exists in two forms, one of them causing visible spots. Factors that can cause the fungus to become more visible include high humidity, as well as immune or hormone abnormalities. However, almost all people with this very common condition are healthy.

As in the majority of paracoccidioidomycosis cases, pulmonary involvement results in shortness of breath, a productive cough and hemoptysis, as well as general symptoms of weight loss, fever and fatigue. Visually, lesions (as pictured) are often present, most commonly on the face.

Paracoccidioidomycosis (PCM) (also known as "Brazilian blastomycosis," "South American blastomycosis,","Lutz-Splendore-de Almeida disease" and "paracoccidioidal granuloma") is a fungal infection caused by the fungus "Paracoccidioides brasiliensis". Sometimes called "South American blastomycosis", paracoccidioidomycosis is caused by a different fungus than that which causes blastomycosis.

Entomophthoramycosis (or Entomophthoromycosis) is a mycosis caused by Entomophthorales.

Examples include basidiobolomycosis and conidiobolomycosis.

Lesions emerge as well-demarcated psoriasiform or hyperkeratotic patches and 36 plaques, with a central clearing and an elevated border. Pagetoid reticulosis is a very slow progressive variant of mycosis fungoides and is usually localized unlike the latter .

The initial lesion is a small subcutaneous swelling following minor trauma. Later, sinuses that discharge purulent and seropurulent exudates containing grains which are fungal colonies are formed. Destruction of deeper tissues, and deformity and loss of function in the affected limbs may occur in later stages.

White piedra (or tinea blanca) is a mycosis of the hair caused by several species of fungi in the genus "Trichosporon". It is characterized by soft nodules composed of yeast cells and arthroconidia that encompass hair shafts.

Ulcerative sarcoidosis is a cutaneous condition affecting roughly 5% of people with sarcoidosis.

Annular sarcoidosis is a cutaneous condition characterized by papular skin lesions arranged in annular

patterns, usually with a red-brown hue.

The following clinical conditions may be considered before diagnosing a patient with mycetoma:

1. Tuberculous ulcer

2. Kaposi's sarcoma, a vascular tumour of skin usually seen in AIDS.

3. Leprosy

4. Syphilis

5. Malignant neoplasm

6. Tropical ulcer

7. Botryomycosis, a skin infection usually caused by the bacteria Staphylococcus aureus.

A cutaneous condition is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment.

Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying causes and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology (chronic blistering conditions), cause (skin conditions resulting from physical factors), and so on.

Clinically, the diagnosis of any particular skin condition is made by gathering pertinent information regarding the presenting skin lesion(s), including the location (such as arms, head, legs), symptoms (pruritus, pain), duration (acute or chronic), arrangement (solitary, generalized, annular, linear), morphology (macules, papules, vesicles), and color (red, blue, brown, black, white, yellow). The diagnosis of many conditions often also requires a skin biopsy which yields histologic information that can be correlated with the clinical presentation and any laboratory data. The introduction of cutaneous ultrasound has allowed the detection of cutaneous tumors, inflammatory processes, nail disorders and hair diseases.

Sarcoidosis involves the skin in about 25% of patients. The most common lesions are erythema nodosum, plaques, maculopapular eruptions, subcutaneous nodules, and lupus pernio. Treatment is not required, since the lesions usually resolve spontaneously in two to four weeks. Although it may be disfiguring, cutaneous sarcoidosis rarely causes major problems.

The most common finding on ear examination is the presence of greyish white thick debris and heaviness in the ear.

Pagetoid reticulosis (also known as "acral mycoses fungoides", "localized epidermotropic reticulosis", "mycosis fungoides palmaris et plantaris", "unilesional mycosis fungoides", and "Woringer–Kolopp disease") is a cutaneous condition, an uncommon lymphoproliferative disorder, sometimes considered a form of mycosis fungoides.

Progressive nodular histiocytosis is a cutaneous condition clinically characterized by the development of two types of skin lesions: superficial papules and deeper larger subcutaneous nodules.

Otomycosis is a fungal ear infection, a superficial mycotic infection of the outer ear canal. It is more common in the tropical countries. The infection may be either subacute or acute and is characterized by malodorous discharge, inflammation, pruritus, scaling, and severe discomfort. Suppuration can occur due to superimposed bacterial infection commonly due to pseudomonas species and proteus species. The mycosis results in inflammation, superficial epithelial exfoliation, masses of debris containing hyphae, suppuration, and pain.

"Distribution" refers to how lesions are localized. They may be confined to a single area (a patch) or may exist in several places. Some distributions correlate with the means by which a given area becomes affected. For example, contact dermatitis correlates with locations where allergen has elicited an allergic immune response. Varicella zoster virus is known to recur (after its initial presentation as chicken pox) as herpes zoster ("shingles"). Chicken pox appears nearly everywhere on the body, but herpes zoster tends to follow one or two dermatomes; for example, the eruptions may appear along the bra line, on either or both sides of the patient.

- Generalized

- Symmetric: one side mirrors the other

- Flexural: on the front of the fingers

- Extensor: on the back of the fingers

- Intertriginous: in an area where two skin areas may touch or rub together

- Morbilliform: resembling measles

- Palmoplantar: on the palm of the hand or bottom of the foot

- Periorificial: around an orifice such as the mouth

- Periungual/subungual: around or under a fingernail or toenail

- Blaschkoid: following the path of Blaschko's lines in the skin

- Photodistributed: in places where sunlight reaches

- Zosteriform or dermatomal: associated with a particular nerve

Subcutaneous granuloma annulare (also known as "Deep granuloma annulare," and "Pseudorheumatoid nodule") is a skin condition of unknown cause, most commonly affecting children, with girls affected twice as commonly as boys, characterized by skin lesions most often on the lower legs.

Typical visible symptoms include rash-like patches, tumors, or lesions. Itching (pruritus) is common, perhaps in 20 percent of patients, but is not universal. The symptoms displayed are progressive, with early stages consisting of lesions presented as scaly patches. These lesions prefer the buttock region. The later stages involve the patches evolving into plaques distributed over the entire body. The advanced stage of mycosis fungoides is characterized by generalized erythroderma, with severe pruritus and scaling.

Drug-induced pseudolymphoma results from exposure to medications, which results in cutaneous inflammatory patterns that resemble lymphoma, most frequently mycosis fungoides.

Treatment for phycomycosis is very difficult and includes surgery when possible. Postoperative recurrence is common. Antifungal drugs show only limited effect on the disease, but itraconazole and terbinafine hydrochloride are often used for two to three months following surgery. Humans with "Basidiobolus" infections have been treated with amphotericin B and potassium iodide. For pythiosis and lagenidiosis, a new drug targeting water moulds called caspofungin is available, but it is very expensive. Immunotherapy has been used successfully in humans and horses with pythiosis. Treatment for skin lesions is traditionally with potassium iodide, but itraconazole has also been used successfully.

Non-mycosis fungoides CD30− cutaneous large T-cell lymphoma is a cutaneous condition that usually presents as solitary or generalized plaques, nodules, or tumors of short duration.

The disease is characterised by the formation of painful abscesses in the mouth, lungs, breast, or gastrointestinal tract. Actinomycosis abscesses grow larger as the disease progresses, often over months. In severe cases, they may penetrate the surrounding bone and muscle to the skin, where they break open and leak large amounts of pus, which often contains characteristic granules (sulfur granules) filled with progeny bacteria. These granules are named due to their appearance, but are not actually composed of sulfur.