The cause is not well defined. Originally considered idiopathic condition. Now accepted that majority of cases develop from dystrophic calcification of cyst contents.

Idiopathic scrotal calcinosis (also known as idiopathic calcified nodules of the scrotum) is a cutaneous condition characterized by calcification of the skin resulting from the deposition of calcium and phosphorus occurring on the scrotum. However, the levels of calcium and phosphate in the blood are normal. Idiopathic scrotal calcinosis typically affects young males, with an onset between adolescence and early adulthood. The scrotal calcinosis appears, without any symptoms, as yellowish nodules that range in size from 1 mm to several centimeters.

Calcinosis cutis may be divided into the following types:

- Dystrophic calcinosis cutis

- Metastatic calcinosis cutis

- Iatrogenic calcinosis cutis

- Traumatic calcinosis cutis

- Idiopathic calcinosis cutis

- Idiopathic scrotal calcinosis

- Subepidermal calcified nodule

- Tumoral calcinosis

- Osteoma cutis

Calcinosis cutis (or cutaneous calcification) is a type of calcinosis wherein calcium deposits form in the skin. A variety of factors can result in this condition. The most common source is dystrophic calcification, which occurs in soft tissue as a response to injury. In addition, calcinosis is seen in Limited Cutaneous Systemic Sclerosis, also known as CREST syndrome (the "C" in CREST). In dogs, calcinosis cutis is found in young, large breed dogs and is thought to occur after a traumatic injury.

Involutional lipoatrophy is a cutaneous condition, and is an idiopathic lipoatrophy characterized clinically by non-inflammatory focal loss of fat.

Idiopathic localized involutional lipoatrophy (ILIL) is a rare and nosologically imprecise condition characterized by a focal loss of subcutaneous tissue on one or several sites, occurring without any significant triggering factor or auto-immune background, and regressing spontaneously within a few months.

The clinical appearance is considerably varied in both the orientation, number, depth and length of the fissure pattern. There are usually multiple grooves/furrows 2–6 mm in depth present. Sometimes there is a large central furrow, with smaller fissures branching perpendicularly. Other patterns may show a mostly dorsolateral position of the fissures (i.e. sideways running grooves on the tongue's upper surface). Some patients may experience burning or soreness.

Milia-like calcinosis is a cutaneous condition characterized by small, milia-like lesions that develop on the dorsal surface of the hands and the face.

Affected individuals typically present with sudden painful proptosis, redness, and edema. Proptosis will vary according to the degree of inflammation, fibrosis, and mass effect. Occasionally, ptosis, chemosis, motility dysfunction (ophthalmoplegia), and optic neuropathy are seen. In the setting of extensive sclerosis there may be restriction, compression, and destruction of orbital tissue. Symptoms usually develop acutely (hours to days), but have also been seen to develop over several weeks or even months.Malaise, headaches, and nausea may accompany these symptoms. Other unusual presentations described include cystoid macular edema, temporal arteritis, and cluster headaches.

Pediatric IOI accounts for about 17% of cases idiopathic orbital inflammation. The most common sign is proptosis, but redness and pain are also experienced. Presentation varies slightly compared to adults with bilateral involvement, uveitis, disc edema and tissue eosinophilia being more common in this population. The presence of uveitis generally implies a poor outcome for pediatric IOI. Bilateral presentation may have a higher incidence of systemic disease.

Sarcoidosis is a systemic disease of unknown cause that results in the formation of non-caseating granulomas in multiple organs. The prevalence is higher among blacks than whites by a ratio of 20:1. Usually the disease is localized to the chest, but urogenital involvement is found in 0.2% of clinically diagnosed cases and 5% of those diagnosed at necropsy. The kidney is the most frequently affected urogenital organ, followed in men by the epididymis. Testicular sarcoidosis can present as a diffuse painless scrotal mass or can mimic acute epididymo-orchitis. Usually it appears with systemic manifestations of the disease. Since it causes occlusion and fibrosis of the ductus epididymis, fertility may be affected. On ultrasound, the hypoechogenicity and ‘infiltrative’ pattern seen in the present case are recognized features. Opinions differ on the need for histological proof, with reports of limited biopsy and frozen section, radical orchiectomy in unilateral disease and unilateral orchiectomy in bilateral disease. The peak incidence of sarcoidosis and testicular neoplasia coincide at 20–40 years and this is why most patients end up having an orchiectomy. However, testicular tumours are much more common in white men, less than 3.5% of all testicular tumours being found in black men. These racial variations justify a more conservative approach in patients of descent with proven sarcoidosis elsewhere. Careful follow-up and ultrasonic surveillance may be preferable in certain clinical settings to biopsy and surgery, especially in patients with bilateral testicular disease.

Two main approaches to genitourinary sarcoidosis have been proposed. Based on the marked relationship between testicular cancer and sarcoidosis, orchiectomy is recommended, even if evidence of sarcoidosis in other organs is present. By contrast, others consider immediate orchiectomy as being quite aggressive because of several factors associated with a benign diagnosis, as well as the involvement of the epididymis or vas deferens and bilateral testicular involvement. If the malignant diagnosis is established by exploration and intraoperative ultrasound-guided biopsy, orchiectomy is performed in cases of diffuse involvement of a testis. Spontaneous resolution has been reported in 50% to 70% of patients with active sarcoidosis. If the diagnosis is not established unequivocally, immunosuppressive agents (frequently steroids) will resolve the inflammation in patients who wish to salvage their fertility; and in those with severely advanced disease, after careful consideration.

A new approach has been proposed recently, based on the absence of evidence for malignant transformation in pathologically confirmed benign diagnosed testicular sarcoidosis, and it involves the open exploration of both testes, with resection of the largest lesion (on the right tunica). In this technique, patient was not given steroids after the operation. Nevertheless, careful follow-up may be preferred to medication or surgery in certain clinical settings.

Idiopathic orbital inflammatory (IOI) disease, or orbital pseudotumor, refers to a marginated mass-like enhancing soft tissue involving any area of the orbit. It is the most common painful orbital mass in the adult population, and is associated with proptosis, cranial nerve (Tolosa–Hunt syndrome), uveitis, and retinal detachment. Idiopathic orbital inflammatory syndrome, also known as orbital pseudotumor, was first described by Gleason in 1903 and by Busse and Hochhmein. It was then characterized as a distinct entity in 1905 by Birch-Hirschfeld. It is a benign, nongranulomatous orbital inflammatory process characterized by extraocular orbital and adnexal inflammation with no known local or systemic cause. Its diagnosis is of exclusion once neoplasm, primary infection and systemic disorders have been ruled-out. Once diagnosed, it is characterized by its chronicity, anatomic location or histologic subtype.

Idiopathic orbital inflammation has a varied clinical presentation depending on the involved tissue. It can range from a diffuse inflammatory process to a more localized inflammation of muscle, lacrimal gland or orbital fat. Its former name, orbital pseudotumor, is derived due to resemblance to a neoplasm. However, histologically it is characterized by inflammation. Although a benign condition, it may present with an aggressive clinical course with severe vision loss and oculomotor dysfunction.

Fiddler’s neck usually involves highly localized lichenification, mild hyperpigmentation, and erythema where the chin rest or instrument body presses against the skin of the neck. Other signs and symptoms include scale buildup, cyst and scar formation, papules and pustules related to local infection, and focal edema. In Blum & Ritter’s study in West Germany (1990), they found that 27% of their population had only minor issues, 72% had a palpable mass at the site, and 23% reported pain and other signs of inflammation such as hyperthermia, pulsation, and cystic, pustular, or papular lesions. Size of masses were an average of 2 cm in diameter ranging up to 4 cm, some being associated with purulent drainage, continuous discharge, and crusting. Dystrophic calcinosis cutis has also been reported. Other serious sequelae include sialolithiasis of the submandibular gland and adenolymphoma of the parotid gland.

The histopathology of fiddler’s neck frequently shows hyperkeratosis and acanthosis, along with plugging of follicles. Histiocytic infiltration with granulomas to foreign body and follicular cysts are also common. Foreign body granulomas are thought to derive from abrasion of the wooden surface of the chin rest and its absorption into the superficial dermis. The location and complex mechanism of causation for fiddler’s neck give rise to a wider spectrum of skin changes when compared to contact dermatitis from more common irritants. Fiddler’s neck can be differentiated from rosacea and sarcoid reaction with granulomas.

The cause of the rare condition of tumoral calcinosis is not entirely understood. It is generally characterized by large, globular calcifications near joints.

Presents as a sensation of food getting stuck (dysphagia) in the mid- or lower esophagus, atypical chest pain, or cough. Patients often state they must drink liquids to swallow solid food. This motility problem results from atrophy of the gastrointestinal tract wall smooth muscle. This change may occur with or without pathologic evidence of significant tissue fibrosis.

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.

Metastatic calcification involves a systemic calcium excess imbalance, which can be caused by hypercalcemia, kidney failure, milk-alkali syndrome, lack or excess of other minerals, or other causes.

CREST causes thickening and tightening of the skin with deposition of calcific nodules ("calcinosis").

Fissured tongue is seen in Melkersson-Rosenthal syndrome (along with facial nerve paralysis and granulomatous cheilitis). It is also seen in most patients with Down syndrome, in association with geographic tongue, in patients with oral manifestations of psoriasis, and in healthy individuals. Fissured tongue is also sometimes a feature of Cowden's syndrome.

Sclerodactyly is a localized thickening and tightness of the skin of the fingers or toes. Sclerodactyly often leads to ulceration of the skin of the distal digits and is commonly accompanied by atrophy of the underlying soft tissues.

The term "sclerodactyly" is made up from the Greek "skleros" meaning hard and "daktylos" meaning a finger or toe – "hard fingers or toes".

It is sometimes associated with scleroderma and mixed connective tissue disease, auto-immune disorders.

Sclerodactyly is a component of the CREST variant of scleroderma (CREST is an acronym that stands for calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia.)

Normophosphatemic familial tumoral calcinosis is a cutaneous disorder characterized by cutaneous calcification or ossification.

Syringomas are harmless eccrine sweat duct tumors, typically found clustered on eyelids, although they may also be found in the armpits, abdomen, chest, neck, scalp or groin area including genitals in a symmetric pattern. They are skin-colored or yellowish firm, rounded bumps, 1–3 mm in diameter, and may be confused with xanthoma, milia, hidrocystoma, trichoepithelioma, and xanthelasma. They are more common in women and are most commonly found in middle-aged Asian women. While they can present at any time in life, they typically present during adolescence. They are usually not associated with any other symptoms although can sometimes cause itchiness or irritation.

The differential diagnoses of fiddler’s neck include branchial cleft cyst, disease of the salivary glands, tumors of the parotid gland, psoriasis, lichen planus, contact dermatitis, herpes simplex and similar infections, and insect bites and stings especially from fleas.

Goldman states that "numerous inherited or congenital conditions display cutaneous telangiectasia".

These include:

- Naevus flammeus (port-wine stain)

- Klippel-Trenaunay syndrome

- Maffucci's syndrome (multiple enchondromas & hemangiomas)

- Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)

- Ataxia-telangiectasia

- Sturge-Weber syndrome, a nevus formation in the skin supplied by the trigeminal nerve and associated with facial port-wine stains, glaucoma, meningeal angiomas and mental retardation

- Hypotrichosis–lymphedema–telangiectasia syndrome, caused by mutation in transcription factor "SOX18"

Hypercementosis is an idiopathic, non-neoplastic condition characterized by the excessive buildup of normal cementum (calcified tissue) on the roots of one or more teeth. A thicker layer of cementum can give the tooth an enlarged appearance, which mainly occurs at the apex or apices of the tooth.

Syringomas can often be diagnosed clinically based on presentation, distribution patterns over the body, lack of associated symptoms and family history. A definitive diagnosis requires a skin biopsy to allow the tissue to be examined under a microscope. Histologically, syringomas have a characteristic comma ("tadpole") shaped tail of dilated, cystic eccrine ducts.

Telangiectasias, also known as spider veins, are small dilated blood vessels near the surface of the skin or mucous membranes, measuring between 0.5 and 1 millimeter in diameter.

These dilated blood vessels can develop anywhere on the body but are commonly seen on the face around the nose, cheeks, and chin. Dilated blood vessels can also develop on the legs, although when they occur on the legs, they often have underlying venous reflux or "hidden varicose veins" (see "Venous reflux" below). When found on the legs, they are found specifically on the upper thigh, below the knee joint, and around the ankles.

Many patients who suffer with spider veins seek the assistance of physicians who specialize in vein care or peripheral vascular disease. These physicians are called vascular surgeons or phlebologists. More recently, interventional radiologists have started treating venous problems.

Some telangiectasias are due to developmental abnormalities that can closely mimic the behaviour of benign vascular neoplasms. They may be composed of abnormal aggregations of arterioles, capillaries, or venules. Because telangiectasias are vascular lesions, they blanch when tested with diascopy.

Telangiectasia is a component of the CREST variant of scleroderma, also known today as limited scleroderma (CREST is an acronym that stands for calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia).