Diagnosis is made primarily through physical assessment of the skin, family history of Mongolian spots, and subjective data given by the care giver. No tests are currently available for diagnosing Mongolian spots.

The diagnosis is based on the combination of the symptoms. Generally, people are diagnosed with yellow nail syndrome if they have two or three of the three classical symptoms (yellow nails, lymphedema and lung problems). The nail changes are considered essential for the diagnosis, but they can be subtle.

Pulmonary function testing can show obstruction of the airways. People with pleural effusions may show evidence of restriction in lung volumes due to the fluid. Analysis of the fluid in pleural effusions generally shows high levels of protein but low levels of cholesterol and lactate dehydrogenase, but about 30% of effusions are chylous (chylothorax) in that they have the characteristics of lymph.

A lymphogram may be performed in people with lymphedema. This can show both under developed (hypoplastic) lymphatic ducts and dilated ducts. Dye may be found in the skin months after the initial test. Scintigraphy of lymph flow (lymphoscintigraphy) shows delays in drainage of lymph (sometimes asymmetrically), although this test can also be normal.

There is no diagnosis as yet for Cutis verticis gyrata (CVH), but it can generally be found out by self, when the person is applying oil to the scalp or getting the hair fully shaven. The ripples are present either in identical form, mostly in the posterior direction, sometimes horizontally also, but it looks more like the ripples of the brain.

There is no clinical diagnosis for CVG as these cases are rarely seen and is often comorbid with other conditions.

People with yellow nail syndrome have been found to have a moderately reduced lifespan compared to people without the condition.

A systematic review has not found evidence that creams and oils are useful for preventing or reducing stretch marks in pregnancy. The safety in pregnancy of one ingredient, Centella asiatica, has been questioned. Evidence on treatments for reducing the appearance of the scars after pregnancy is limited.

There is no 'cure' for this condition and currently, medical treatment is limited to plastic surgery with excision of the folds by means of scalp reduction/surgical resection. Scalp subcision has also been suggested as a treatment. Additional suggestions also include injections of a dermal filler i.e. Sculptra (poly-L-lactic acid)

Mongolian spots usually resolve by early childhood and hence no treatment is generally needed if they are located in the sacral area. However, sometimes it may be required for extra sacral lesions to have surgical correction. Q-switched alexandrite lasers have been used for treatment. Good results are obtained if treatment is initiated before the age of 20 years. In a study done by the University of Tokyo, the effectiveness of the Q-switched alexandrite laser in treating Mongolian spots was evaluated. A retrospective study was done from April 2003 to September 2011. 16 patients, aged 14-55, were treated with Q-switched alexandrite laser. A good therapeutic outcome was achieved on the whole group, however two patients with sacral Mongolian spots suffered from inflammatory hyperpigmentation, and two patients got post inflammatory hypopigmentation after seven sessions of laser treatment.

The definitive diagnosis is by histologic analysis, i.e. and examination under the microscope.

Under the microscope, OKCs vaguely resemble keratinized squamous epithelium; however, they lack rete ridges and often have an artifactual separation from their basement membrane.

On a CT scan, The radiodensity of a keratocystic odontogenic tumour is about 30 Hounsfield units, which is about the same as ameloblastomas. Yet, ameloblastomas show more bone expansion and seldom show high density areas.

Leukoedema is a harmless condition, and no treatment is indicated. People may be alarmed by the appearance and benefit from reassurance.

Treatment is by excisional biopsy, wide local excision and possibly sentinel node biopsy. Spread of disease to local lymph nodes or distant sites (typically brain, bone, skin and lung) marks a decidedly poor prognosis.

Radiologically

- Odontogenic Myxoma

- Ameloblastoma

- Central Giant Cell Granuloma

- Adenomatoid odontogenic tumor

Histologically

- Orthokeratocyst

- Radicular cyst (particularly if the OKC is very inflamed)

- Unicystic ameloblastoma

The diagnosis is usually made on the clinical appearance, and tissue biopsy is not usually needed. The histologic picture is one of superficial candidal hyphal infiltration and a polymorphonuclear leukocytic inflammatory infiltrate present in the epithelium. The rete ridges are elongated and hyperplastic (pseudoepitheliomatous hyperplasia, which may be mistaken for carcinoma).

There is no clearly useful treatment for stretch marks though various things are tried.

Various efforts that have been tried including laser treatments, glycolic acid, and microdermabrasion. Topical tretinoin is categorized by the FDA as a known teratogen (causing malformations in fetuses) in animals, without adequate human studies on safety in pregnancy.

Carboxytherapy has been used; however, there is a lack of evidence to support its use.

Rombo syndrome is a very rare genetic disorder characterized mainly by atrophoderma vermiculatum of the face, multiple milia, telangiectases, acral erythema, peripheral vasodilation with cyanosis and a propensity to develop basal cell carcinomas.

The lesions become visible in late childhood, began at ages 7 to 10 years and are most pronounced on the face, At that time a pronounced, somewhat cyanotic redness of the lips and hands was evident as well as moderate follicular atrophy of the skin on the cheeks. In adulthood, whitish-yellow, milia-like papules and telangiectatic vessels developed. The papules were present particularly on the cheeks and forehead, gradually becoming very conspicuous and dominating the clinical picture. Trichoepitheliomas were found in 1 case. In adults, the eyelashes and eyebrows were either missing or irregularly distributed with defective and maldirected growth. Basal cell carcinomas were a frequent complication. The skin atrophy was referred to as vermiculate atrophoderma. Basal cell carcinomas may develop around the age of 35. Histological observations during the early stage include irregularly distributed and atrophic hair follicles, milia, dilated dermal vessels, lack of elastin or elastin in clumps. After light irradiation a tendency to increased repair activity was observed both in epidermis and in the dermal fibroblasts.

Histologic sections showed the dermis to be almost devoid of elastin in most areas with clumping of elastic material in other areas. The disorder had been transmitted through at least 4 generations with instances of male-to-male transmission.

Cutis marmorata also occurs in decompression sickness (DCS). Although it is considered Type I DCS, which is non-neurological, it is typically treated as if the patient has the more severe Type II DCS. This is because past experience in diving medicine has shown that patients initially presented with only this symptom have a high likelihood of progression to neurological, Type II, DCS without prompt treatment. The marbling does not resolve until few days after treatment, but any pruritus (itching) will likely disappear upon initial recompression.

When a newborn infant is exposed to low environmental temperatures, an evanescent, lacy, reticulated red and/or blue cutaneous vascular pattern appears over most of the body surface. This vascular change represents an accentuated physiologic vasomotor response that disappears with increasing age, although it is sometimes discernible even in older children.

Persistent and pronounced cutis marmorata occurs in Menke's disease, familial dysautonomia, Cornelia de Lange, trisomy 13 and trisomy 18 syndromes.

Also seen in Cardiogenic Shock.

Cutis marmorata telangiectatica congenita is clinically similar, but the lesions are more intense, may be segmental, are persistent, and may be associated with loss of dermal tissue, epidermal atrophy and ulceration.

Many conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square meters, and is made of three distinct layers: the epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin. Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. In the embryo, the epidermis, hair, and glands form from the ectoderm, which is chemically influenced by the underlying mesoderm that forms the dermis and subcutaneous tissues.

The epidermis is the most superficial layer of skin, a squamous epithelium with several strata: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. Nourishment is provided to these layers by diffusion from the dermis, since the epidermis is without direct blood supply. The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95 percent of the epidermis. This stratified squamous epithelium is maintained by cell division within the stratum basale, in which differentiating cells slowly displace outwards through the stratum spinosum to the stratum corneum, where cells are continually shed from the surface. In normal skin, the rate of production equals the rate of loss; about two weeks are needed for a cell to migrate from the basal cell layer to the top of the granular cell layer, and an additional two weeks to cross the stratum corneum.

The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing.

The subcutaneous tissue is a layer of fat between the dermis and underlying fascia. This tissue may be further divided into two components, the actual fatty layer, or panniculus adiposus, and a deeper vestigial layer of muscle, the panniculus carnosus. The main cellular component of this tissue is the adipocyte, or fat cell. The structure of this tissue is composed of septal (i.e. linear strands) and lobular compartments, which differ in microscopic appearance. Functionally, the subcutaneous fat insulates the body, absorbs trauma, and serves as a reserve energy source.

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 etiologies 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), etiology (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). 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.

Heck's disease (also known as focal or multifocal epithelial hyperplasia) is an asymptomatic, benign neoplastic condition characterized by multiple white to pinkish papules that occur diffusely in the oral cavity. Can present with slightly pale, smooth or roughened surface morphology. It is caused by the human papilloma virus types 13 and 32. It exhibits surface cells with vacuolated cytoplasm around irregular, pyknotic nuclei and occasional cells with mitosis-like changes within otherwise mature and well-differentiated epithelium. A distinguishing histologic feature is elongated rete ridges resembling Bronze Age axe with mitosoid bodies present. It was first identified in the Aboriginal population.

Over time, they will spontaneously regress without treatment. Possible treatment may be excisional biopsy for lesions of functional or aesthetic concern.

Melanoma with features of a Spitz nevus (also known as a "Spitzoid melanoma") is a cutaneous condition characterized histologically with tissue similar to a spitz nevus and with overall symmetry and a dermal nodule of epithelioid melanocytes that do not mature with progressively deeper dermal extension.

There are at least four types of FFDD:

- Type I: autosomal dominant FFDD

- Type II: autosomal recessive FFDD

- Type III: FFDD with other facial features

- Type IV: facial lesions resembling aplasia cutis in a preauricular distribution along the line of fusion of the maxillary and mandibular prominences. Autosomal recessive.

Leukoedema lesions disappear when the mucosa is stretched, which helps to differentiate it from other white lesions in the mouth. The differential diagnosis is with leukoplakia, oral candidiasis, oral lichen planus, white sponge nevus, morsicatio buccarum, hereditary benign intraepithelial dyskeratosis and dyskeratosis congenita. Tissue biopsy is not indicated, but when taken, the histologic appearance is one of increased epithelial thickness, broadening and eleongation of the rete ridges, parakeratosis and intracellular edema of the spinous layer. The cells of the spinous later are vacuolated, large and possess pyknotic nuclei. The superficial squamous cells have a clear, seemingly empty cytoplasm but it has not been shown that there is an increase in intracellular water, possibly making the term edema misleading. The histologic appearance is thought to be caused by water within the cells of the spinous layer causing the light to reflect back as whitish. The diagnosis is usually made based on the clinical appearance alone, but oral exfoliative cytology has been used as a diagnostic aid.

Beau's lines are deep grooved lines that run from side to side on the fingernail or the toenail. They may look like indentations or ridges in the nail plate. This condition of the nail was named by a French physician, Joseph Honoré Simon Beau (1806–1865), who first described it in 1846.

Beau's lines are horizontal, going across the nail, and should not be confused with vertical ridges going from the bottom (cuticle) of the nail out to the fingertip. These vertical lines are usually a natural consequence of aging and are harmless. Beau's lines should also be distinguished from Muehrcke's lines of the fingernails. While Beau's lines are actual ridges and indentations in the nail plate, Muehrcke lines are areas of hypopigmentation without palpable ridges; they affect the underlying nail bed, and not the nail itself. Beau's lines should also be distinguished from Mees' lines of the fingernails, which are areas of discoloration in the nail plate.

There are several causes of Beau's lines. It is believed that there is a temporary cessation of cell division in the nail matrix. This may be caused by an infection or problem in the nail fold, where the nail begins to form, or it may be caused by an injury to that area. Some other reasons for these lines include trauma, coronary occlusion, hypocalcaemia, and skin disease. They may be a sign of systemic disease, or may also be caused by an illness of the body, as well as drugs used in chemotherapy or malnutrition. Beau's lines can also be seen one to two months after the onset of fever in children with Kawasaki disease.

Human nails grow at a rate which varies with many factors: age, and the finger or toe in question as well as nutrition. However, typically in healthy populations fingernails grow at about 0.1mm/day and toenails at about 0.05mm/day. With this in mind the date of the stress causing Beau's lines and other identifiable marks on nails can be estimated. As the nail grows out, the ridge visibly moves upwards toward the nail edge. When the ridge reaches the nail edge, the fingertips can become quite sore due to the mis-shapen nail pressing into the flesh deeper than usual, exposing the sensitive nail bed (the quick) at the nail edge.

A researcher found Beau's lines in the fingernails of two of six divers following a deep saturation dive to a pressure equal to 305 meters of sea water, and in six of six divers following a similar dive to 335 meters. They have also been seen in Ötzi the Iceman.

This disease is caused by problems in the circulatory system, so when it is presented, in the beginning it is important to follow several recommendations. The person needs to keep the legs elevated as much as possible to help the return of the blood. Whenever sitting down, the person needs to keep the legs on a foot stool. At night it is advisable to sleep with a pillow under the lower legs. In the evening, t is not unusual for legs to be swollen. The volume of the lower leg can increase to up to 100ml after a long working day or up to 200ml after a long-haul flight without moving.

In the example of the 41-year-old Japanese man the lesions were much improved by washing and topical use of corticosteroids for two months, also oral antibiotics like cephalexin are used if cellulitis is present. Moist exudative inflammation and moist ulcers respond to tepid wet compresses of Burow’s solution or just saline or water for 30 to 60 minutes several times a day. But in worse cases, edema that does not disappear spontaneously within a few hours or after a walk, is described as pathological, so it needs to have a special treatment. It is very important to say that Papillamitosis, bilateral and marked edema with few symptoms is mostly caused by the systemic circulation (heart, kidneys, liver).

Papillamitosis is associated, as has been mentioned before, with symptoms and/or clinical signs such as dilated superficial veins, varicose veins and changes in the skin. Edema and its complication Papillamitosis are only partially reversible and soon becomes hard, which is mainly confirmed on palpation. All skin structures are affected and this is characterized by the term. Lymphoedema may develop in many cases accompanied by acral thickening of the skin folds, hyperkeratosis and papillomatosis.

Trachyonychia, sometimes called sandpapered nails, is a condition characterized by rough accentuated linear ridges (longitudinal striations) on the nails of the fingers and toes. When the condition occurs on all the twenty nails of the fingers and toes, it is known as twenty-nail dystrophy, most evident in childhood, favoring males.

Trachyonychia causes the nails to become opalescent, thin, dull, fragile, and finely longitudinally ridged, and, as a result, distally notched. It can be a manifestation of lichen planus, psoriasis, alopecia areata, immunoglobulin A deficiency, atopic dermatitis, and ichthyosis vulgaris.

"The longitudinal striations can occur as a normal part of the aging process", and not until the nails start to thin and get a sandpaper look is the condition called trachonychia. The nails are opalescent and frequently are brittle and split at the free margin. There has been evidence of the condition as a cutaneous manifestation of lichen planus. It has also been associated with other diseases such as eczema, psoriasis, alopecia areata, and atopic dermatitis. Trachonychia is often seen in vitiligo patients – suggesting that they are more susceptible to this condition.

Most birthmarks are harmless and do not require treatment. Pigmented marks can resolve on their own over time in some cases. Vascular birthmarks may require reduction or removal for cosmetic reasons. Treatments include administering oral or injected steroids, dermatological lasers to reduce size and/or color, or dermatologic surgery.