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Causes of Skin, Hair and Nail Diseases

Skin, hair and nail diseases are caused by numerous factors. This is due to the fact that the skin is the largest organ in the body, it comes in contact with the external environment and numerous products are applied to it each and every day. These factors which cause skin, hair and nail diseases include:


Skin, Hair and Nail Diseases Caused by Bacteria


Abscess (plural abscesses) are caused by bacteria. Symptoms of abscesses include warm and painful swellings which contain pus.


skin of color skin diseases pictures

Acne Vulgaris

Acne vulgaris is one skin condition that is caused by a combination of factors that include a bacteria known as Propionibacterium acnes, increased oil production by the skin, abnormal shedding of skin cells and inflammation. Click here to learn more about acne vulgaris.


recurring acne

Bullous Impetigo

Symptoms of bullous impetigo include blisters which tend to rupture and the fluid oozes out. The lesions then develop golden honey colored crusts which can be itchy.

bullous impetigo

Nonbullous Impetigo

Symptoms of non-bullous impetigo include small pustules (pus filled swellings) that become red patches with golden honey colored crusts. These patches ooze fluid and gradually increase in size.


non bullous Impetigo


Symptoms of secondary syphilis include moth eaten hair loss.


moth eaten hair loss

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Skin, Hair and Nail Diseases Caused by Chemicals

Allergic Contact Dermatitis

Allergic contact dermatitis develops when the skin is exposed to the sensitizing chemicals. Symptoms include redness, itching and scaling which develop in areas that come in contact with the chemicals as well as in areas that do not.

nickel dermatitis

Chemical Alopecia

Chemical alopecia is a type of hair loss that develops after using strong chemicals on the hair to color it, bleach it or relax it. It is characterized by the hair breaking off and leaving bald spots on the scalp which may also become itchy and sore.ask a dermatologist free

Hand Eczema

Hand eczema or occupational dermatitis is another type of irritant contact dermatitis which develops as a result of coming in contact with harsh detergents. Symptoms of hand eczema include red, hyperkeratotic or scaly areas with fissures and mild swelling on the hands.

irritant contact dermatitis


Irritant Contact Dermatitis

Irritant contact dermatitis symptoms are similar to those of allergic contact dermatitis but they only develop in areas which come in contact with the irritating chemical.

Irritant Contact Dermatitis

Lip Licker’s Dermatitis

Lip licker’s dermatitis is a type of irritant contact dermatitis whose symptoms include dark patches around the mouth. As the name suggests, it develops as a result of licking the lips.

lip licker's dermatitis

Nairobi Fly Dermatitis

Nairobi fly dermatitis which  is also known as blister beetle dermatitis develops when chemicals from the blister beetle come in contact with the skin. Symptoms of this condition include vesicles (small swellings with fluid) and bullae (blisters) which are associated with redness and swelling.

nairobi fly dermatitis

Occupational Acne

Occupational acne is one condition that is caused by chemicals that a person comes in contact with in their line of duty.

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Skin, Hair and Nail Diseases Caused by Diet

Acrodermatitis Enteropathica

Acrodermatitis enteropathica is caused by zinc deficiency.


Angioedema has many causes which include consuming nuts and seafood. It is characterized by swellings on the lips and other parts of the face as well as on the hands, feet and genitals.

skin of color diseases


Pellagra is a nutritional disease which affects the skin. It is caused by poor intake of vitamin B3. Symptoms of pellagra dermatitis or pellagroderma include erythematous (red) skin with blisters that burst to reveal erosions. These red areas later become brownish in color and the scaling appears on areas exposed to sunlight. This dermatitis has a clear demarcation between the affected and the unaffected areas.

vitamin B 3 niacin deficiency

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Skin, Hair and Nail Diseases caused by Environment Factors

Atopic Dermatitis

Eczema or atopic dermatitis is caused by a combination of environmental factors and genetics.

atopic dermatitis in adults

Miliaria Crystallina

Symptoms of miliaria crystallina include small, clear vesicles (blisters) which occur in crops. They break easily since they are very fragile.

heat rash skin of color

Plantar Xerosis

Symptoms of plantar xerosis include skin on the feet which is dry, rough, flaky and peeling.

dry, rough feet

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Skin, Hair and Nail Diseases  Caused by Fungi


Onychomycosis or fungal nail infection is obviously caused by fungi. Ringworms or Tinea corporis are caused by fungi. Symptoms of onychomycosis include changes in the color and the shape of their nail which can become yellowish and thickened. These changes are initially painless but as the disease progresses, the nails may become painful and cause difficulties walking and performing their occupation.

fungal nail infection

Tinea Cruris

Symptoms of tinea cruris include pruritic (itchy) and erythematous (red) lesions which have a clearly defined border. These lesions are usually on the inguinal folds, perineal area, penis, scrotum, anal area and upper thighs.

tinea cruris treatment

Tinea Versicolor

Symptoms of tinea versicolor include several round to oval macules and patches that can coalesce to involve large areas. These patches which do not tan, are usually hypopigmented or whitish in persons with dark skin and salmon or pink colored in persons with light skin.

pityriasis versicolor

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Skin, Hair and Nail Diseases Caused by Genes


Albinism is a group of inherited diseases passed through genes. These disorders are characterized by white skin, white hair, eye problems and an increased risk of developing skin cancer due to absent or reduced levels of a skin pigment known as melanin.

albino Tanzania

Atypical Moles

Atypical moles or dysplastic nevus can be caused by genes or they can occur sporadically. Symptoms of atypical moles include indistinct edges, uneven coloration with a mixtures of colors which can range from brown to pink. They are often flat and their surface can be smooth, scaly or pebbly. They are usually more than 5 mm or ¼ inch wide.

dysplastic nevus

Common Moles

Common moles can be caused by genes or they can occur sporadically. Symptoms of common moles include swellings which are round or oval in shape. These dome shaped swellings have a smooth surface, a distinct edge and even coloration. They are usually less than 5 mm or ¼ inch wide.

mole ABCDE

Dermatosis Papulosa Nigra

Dermatosis papulosa nigra is a skin disorder attributed to inheritance.

Dermatosis Papulosa Nigra



Freckles or ephelides are caused by genes though exposure to the sun influences their manifestation. Symptoms of freckles include small (usually less than 3 mm), flat discolored areas which develop on sun exposed areas like the cheeks and forehead. These circular spots are usually tan or light brown in color.

leg freckles


Ichthyosis is caused by genes. Symptoms of ichthyosis include dry skin with a fish-like scale.

dry skin

Keratosis Pilaris

Keratosis pilaris is an inherited disorder which affects keratination of the hair follicles. Symptoms of keratosis pilaris include numerous, small (1-2 mm), rough papules (swellings) on the skin which give it the appearance of goose bumps or chicken skin and the texture of sandpaper.


keratosis pilaris


The genes that a person inherits from their parents contribute to the development of psoriasis. This condition can present as:

Palmoplantar psoriasis – Symptoms of palmoplantar psoriasis include erythematous (red), scaly plaques which commonly develop on the central palm and weight bearing areas of the soles. There may also be generalized thickening and scaling of the palms and soles with painful fissures (cracks).

palmoplantar psoriasis

Penis psoriasis – Symptoms of penis psoriasis include dry, red lesions which usually develop on the glans penis and the corona. There may also be some scaling especially on the shaft and in circumcised men.

penis psoriasis

Plaque psoriasis – Symptoms of plaque psoriasis include inflamed red-pink patches of skin which are covered by silvery-white scales. The lesions are roundish with well-defined borders.

Scaly Skin Diseases

Scalp psoriasis – Symptoms of scalp psoriasis include reddish patches on the scalp with a silvery white scale. There may be itching which can be severe enough to disrupt sleep. There may also be temporary hair loss. Scalp psoriasis can also extend to affect the face and the skin behind the ears.

scalp psoriasis treatment

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Skin, Hair and Nail Diseases Caused by Habits

Acne Scars

Acne scars are caused by picking acne lesions. They can present in the following ways:

1. Ice Pick Scars which are deep holes with narrow openings on the skin. They have a V-shaped cross-section.

2. Boxcar Acne Scars which are round or oval or polygonal depressions with boxlike walls in the skin. They have a U-shaped cross-section.

3. Rolling Scars which are usually wide and shallow. They give the skin an uneven, wavy texture.

4. Hypertrophic Scars which are elevated above the skin and they are the same size as the original acne lesion.

5. Keloid Scars which are elevated above the skin and they extend outside the margins of the original acne lesion.

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Calluses are caused by frequent pressure and friction. Sources of this frequent pressure on the feet include wearing poorly fitting shoes and frequent walking.

calluses Nairobi Kenya

Ingrown Toenails

Ingrown toenails or onychocryptosis are caused by wearing poorly fitting shoes though foot injuries also play a role. Symptoms of an ingrown toenail include a swollen, warm, erythematous (red) and painful toe.

ingrown toenails

Lichen Simplex Chronicus

Lichen simplex chronicus or neurodermatitis develops when the skin is injured by recurrent scratching. Symptoms of lichen simplex chronicus include include a localized area which is itchy, dry, scaly, hyperpigmented (darker than the surrounding skin) and lichenified (thickened).


Pseudofolliculitis Barbae

Pseudofolliculitis barbae develops after shaving. Symptoms of pseudofolliculitis barbae include papules (small bumps) which are usually skin-colored or red and which may have a hair shaft in their center. They are usually painful.

Pseudofolliculitis Barbae

Traction Alopecia

Traction alopecia is a type of hair loss caused by habitually wearing tight braids or ponytails. Symptoms of traction alopecia include gradual and painless localized hair loss which causes bald patches that are usually along the hair line. There may also be associated headaches and pain on the scalp due to the tight hairstyles but not due to the traction alopecia.

alopecia traction

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Skin, Hair and Nail Diseases Caused by Insects

Bedbug Bites

Symptoms of bed bug bites include red, itchy papules (small swellings) which tend to be in a line with 3 to 5 bites. Bedbugs usually bite on the face, neck, hands and arms.

bed bug bites

Chigger Bites

Symptoms of chiggers bites begin 1-3 hours after a bite which was noticed when the chigger begins to inject digestive enzymes into the skin. These symptoms include intense itching which may persist for several days. The area may also become red and raised.

chigger bites

Mosquito Bites

Symptoms of mosquito bites include a stinging pain as it pierces the skin. This is followed by the development of itchy, red papules (small swellings) which can be skin colored in people with dark skin. Wheals may also develop as the immune system reacts to proteins in the mosquito’s saliva.

mosquito bites

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Skin, Hair and Nail Diseases Caused by Medical Conditions

Acanthosis Nigricans

Acanthosis nigricans is associated with diabetes. Symptoms of acanthosis nigricans include dark brown, velvety discolorations in body folds like the armpits, neck and groin. The affected skin can also become thickened.

acanthosis nigricans

Papular Pruritic Eruption

Papular pruritic eruption (PPE) is associated with HIV infection. Symptoms of papular pruritic eruption include rashes with multiple, small, itchy, red or skin colored papules (pimples). In dark skinned persons, these papules may be hyperpigmented. 2. These papules may be superficially eroded due to the pruritis. Sterile pustules and excoriations may also be present.


Post Inflammatory Hyperpigmentation

Post inflammatory hyperpigmentation (PIH) develops after conditions which cause inflammation in the skin like acne and chickenpox. Symptoms of post inflammatory hyperpigmentation include macules  (dark spots) and patches which are darker than the surrounding skin. These spots vary in color as Caucasians tend to develop pink or red marks while persons with darker skin develop purplish, brown and black discolorations.

Post Inflammatory Hyperpigmentation Treatment

Post Inflammatory Hypopigmentation

Post inflammatory hypopigmentation develops after conditions which cause inflammation in the skin like chickenpox and eczema. Symptoms of post inflammatory hypopigmentation include macules and patches which are lighter than the surrounding skin.

Chickenpox Post Inflammatory Hypopigmentation

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Skin, Hair and Nail Diseases Caused by Medications

Acneiform Eruptions

Acneiform eruptions can be caused by corticosteroids which are used to treat numerous conditions. Symptoms of acneiform eruptions include monomorphic (uniform) lesions which can be papules (small swellings), papulopustules (small swellings with pus), nodules (larger swellings) or cysts (fluid-filled swellings). These lesions can develop on parts of the body not normally affected by acne vulgaris like the arms and legs.

skin of color diseases

Confetti Hypopigmentation

Hydroquinone which is used to treat conditions like melasma can cause confetti depigmentation. Symptoms of confetti hypopigmentation include hypopigmented macules or small, flat, white spots on the skin.

white spots on skin


Perioral Dermatitis

Perioral dermatitis is caused by the application of steroid creams. Symptoms of perioral dermatitis include erythematous papules (small, red swellings) which develop around the mouth. This rash spares the vermillion border around the mouth.

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Tinea Incognito

Tinea incognito is caused by the use of steroid creams to treat fungal infections of the skin. Symptoms of tinea incognito include the alteration of tinea corporis lesions which are usually round with central clearing and a raised border. The lesions become larger and less scaly and they may also develop pustules (small pus filled swellings).

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Urticaria can be caused by medications and many other things. Symptoms of urticaria can develop within minutes to hours of coming in contact with the causative allergen. These symptoms include intensely pruritic (itchy), elevated, well-circumscribed papules and plaques (swellings) with localized edema (swelling). This localized edema results in lesions which are palpable lesion. The lesions of urticaria are erythematous (red) though they can be flesh colored in dark skinned people. Urticarial lesions are also non-scaly and they blanch completely when pressure is applied to them.


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Skin, Hair and Nail Diseases Caused by Sunlight

Basal Cell Carcinoma

Basal cell carcinoma (BCC) is a type of skin cancer which develops when ultraviolet (UV) radiation from the sun damages the DNA of the skin cells.

basal cell carcinoma

Malignant Melanoma

Malignant melanoma is another type of skin cancer that develops after exposure to UV rays from the sun.


Solar Lentigo

Solar lentigo develop when the skin is damaged by ultraviolet rays. Symptoms of solar lentigo include pigmented flat areas of around 5 mm. These lesions slowly increase in number and size and they may coalesce to form pigmented patches of around 20mm. These black or brown or tan areas are well circumscribed and surrounded by normal skin.



Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) is another type of skin cancer that also develops after exposure to UV rays from the sun.


Symptoms of sunburns include redness of the skin and discomfort or pain. Blisters and swelling are present in severe sunburns.

skin of color disease pictures

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Skin, Hair and Nail Diseases Caused by The Body

Alopecia Areata

Alopecia areata develops when cells from the immune system attack the hair follicles and cause patchy hair loss on the scalp, beard and other hair bearing areas of the body.

beard hair loss


Congenital Nevi

The cause of congenital nevi is not clear but they are suspected to develop due to defects that occur in the fetus.

tatto over mole


Linear Immunoglobulin A Dermatosis

Symptoms of Linear Immunogloblin A dermatosis include tense vesicles and bullae which are roundish and usually clear though they may also be hemorrhagic. These vesicles and bullae can develop on normal or erythematous (red) skin.

chronic byllous dermatosis

Pearly Penile Papules

Pearly penile papules (PPP) are not a skin disease or sexually transmitted infection. They are a variant of the normal male anatomy. Symptoms of pearly penile papules include small (1-3 mm diameter), shiny, smooth swellings which usually develop around the corona or sulcus of the glans penis (head of the penis). In some situations ectopic PPP may develop on the shaft of the penis.

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Pemphigus Foliaceous

Symptoms of pemphigus foliaceous include superficial blisters which are very hard to find since they easily rupture and transition into erosions. Other symptoms include scaly and crusted erosions on an erythematous (red), inflamed base.

pemphigus foliaceous

Pemphigus Vulgaris

Symptoms of pemphigus vulgaris include flaccid blisters which can develop on normal skin or on erythematous (red) skin.

autoimmune skin diseases

Seborrheic Dermatitis

Seborrheic dermatitis is thought to be caused by an abnormal response by the immune system to a yeast known as Malassezia. Symptoms of seborrheic dermatitis include erythematous (red or pink), greasy patches with fine scaling (‘dandruff’). These patches may also have thick, adherent yellowish brown crusts on top of them.

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Vitiligo develops when cells from the immune system destroy those which produce the pigment known as melanin that gives the skin its color. Symptoms of vitiligo include patches of skin which have lost their normal skin color and become lighter than the surrounding areas.

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Xanthelasma develop as a result of deposition of lipids in the cells within the skin known as foam cells. Symptoms of xanthelasma include a painless, soft, yellowish swelling on the eyelid.

skin of color disease pictures

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Skin, Hair and Nail Diseases Caused by Viruses

Aphthous Ulcers

Aphthous ulcers are caused by viruses. These are recurrent, painful wounds in the mouth.

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Genital Herpes

Genital warts are caused by Herpes Simplex Virus 2 (HSV-2). Symptoms of genital herpes include blisters (fluid filled swellings) which develop in the private areas. They usually break open and turn into painful erosions (small wounds). The wounds/sores develop scabs and heal over the course of a few weeks.


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Gianotti Crosti Syndrome

Gianotti Crosti Syndrome which is also known as infantile papular acrodermatitis or papulovesicular dermatitis of childhood, is thought to be caused by a skin reaction to a viral infection. Viruses linked to this condition include hepatitis B virus, Epstein Barr virus and cytomegalovirus.


Herpes Gladiatorum

Herpes gladiatorum or mat herpes is caused by herpes simplex virus 1 (HSV1). Symptoms of herpes gladiatorum include painful clusters of blisters which may  be associated with fever. This infection which is common in athletes and often affects the chest, back, arms and legs.

Herpes gladiatorum

Herpes Labialis

Herpes labialis is usually caused by the Herpes Simplex Virus 1 (HSV-1). Symptoms of  herpes labialis include small, painful blisters which develop on the lips and mouth. These blisters which are filled with clear fluid, break open and evolve into ulcers.

herpes labialis

Herpes Zoster

Symptoms of herpes zoster include blisters (fluid filled swellings) which develop on one side of the body over the skin that is supplied by the nerve that has been affected by the virus. These blisters dry up and form scabs. There is also associated pain which typically precedes the rash by around 2 days and it can range from mild to severe.

herpez zoster


Warts are caused by viruses. They can present as:

Anogenital warts – Symptoms of anogenital warts include flesh colored swellings on the skin over the anus and genital organs. Those swellings that develop on moist areas like the vulva are soft while those that develop on dry areas like the penis are firm.


anogenital warts

Periungal warts – Symptoms of periungal warts include small, smooth and translucent swellings which grow within several weeks or months into rough and hyperkeratotic (scaly) papules (swellings) around fingernails and toenails.

skin of color skin diseases pictures


Plantar warts – Symptoms of plantar warts include rough, flesh colored, hyperkeratotic (scaly) papules which may be single or multiple. These swellings are usually painless but they may become painful if they are on areas that receive much pressure when walking or standing such as over the heads of the metatarsals and on the heels.

Scalp warts – Symptoms of scalp warts include flesh colored swellings on scalp.

scalp wart

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Skin, Hair and Nail Diseases Caused by Unknown Factors

Cutaneous T Cell Lymphoma

Cutaneous T cell lymphoma (CTLC) or mycosis fungoides is a type of skin cancer whose cause is not known. Symptoms of CTLC include patches which resemble those of eczema, plaques and swellings.

mycosis fungoides

Hypertrophic Scars

Symptoms of hypertrophic scars include flesh-colored, red or pink swellings which develop over site where the skin had been injured but do not extend beyond the margins of the injury.

African American hypertrophic scars



Symptoms of keloid scars include flesh-colored, red or pink swellings which develop over site where the skin had been injured and extend beyond the margins of the injury.

African American keloid scar


Idiopathic Recurrent Palmoplantar Eccrine Hidradenitis

Symptoms of idiopathic recurrent palmoplantar eccrine hidradenitis include painful, reddish to violet colored swellings on the soles and palms.

idiopathic recurrent palmoplantar hidradenitis

Morgellons Disease

Morgellons disease is a mysterious disease whose cause is still under debate. Some specialists think it is a psychiatric delusional disorder while others think it has infectious or environmental origins. Symptoms of Morgellons disease include sensations of insects crawling all over the skin which are often associated with disfiguring sores. Patients also report the presence of black thread-like substances or fibers on the skin and sores.

Morgellons Disease

Pityriasis Rosea

The cause of pityriasis rosea is not known for sure but viruses like human herpes virus (HHV-7) as well as drugs like acetylsalicylic acid and barbiturates are suspected to be contribute to its development. Symptoms of pityriasis rosea include a single, oval lesion which usually measures between 2-10 cm and is known as the herald patch. It is usually located on the trunk and it is followed by smaller, symmetrical daughter lesions which measure around 5-10 mm.

pityriasis rosea


Symptoms of poikiloderma include mottled hyperpigmentation (dark discoloration), hypopigmentation (light discoloration) and atrophy (thinning skin) with telangiectases (dilated capillaries).


Pyogenic Granuloma

Pyogenic granuloma develop during pregnancy and after taking some medications. Symptoms of pyogenic granuloma include a swelling which arises suddenly, bleeds easily and grows quickly.

lobular capillary hemangioma


Rosacea is another condition whose cause in not really known. It can present as:

Erythematotelangiectatic rosacea – Symptoms of erythematotelangiectatic rosacea include telangiectasia (dilated small blood vessels) and flushing of the nose and cheeks.

Papulopustular rosacea – Symptoms of papulopustular rosacea, which is also known as classical rosacea, include erythematous papules (small red swellings) which are associated with tiny pustules (pus filled swellings).

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Common Causes of Skin, Hair and Nail Diseases

From our observation the most common causes of skin, hair and nail diseases are bacteria, viruses and chemicals. The treatment of these skin, hair and nail conditions is as varied as their causes. Therefore if you notice any rashes, swellings or you develop itching, scaling on any part of your body Consult a Doctor to get the right treatment.

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Categorised as: Dermatology Atlas

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