Skin diseases due to mechanical and thermal causes

From WikiLectures

Mechanical causes[edit | edit source]

Pressure blister (epidermolysis bullosa traumatica, traumatic bulla)[edit | edit source]

A blister on the non-inflamed underlying skin at the site of pressure

Clinical image[edit | edit source]

After manual hand activity, new shoes, long walking, orthopedic defects, blister solit.x multiple, firm covering, sometimes hemorrhagic contents, surrounding normal color

Therapy[edit | edit source]

Wipe over with disinfectant, puncture, tape over.



Callus (tyloma, casus)[edit | edit source]

Focal hyperkeratosis induced by mechanical stress, a defensive reaction

Clinical image[edit | edit source]

Most commonly hands, feet, indistinctly circumscribed stiff slightly raised papule, surface mostly rough, peeling, sometimes painful cracks, sometimes professionally (fingers of violinists)

Differential diagnosis[edit | edit source]

Clavus, keratoma palmare, jantare

Therapy[edit | edit source]

Softening ointments with salicylic acid or urea, removing the mech.action


Corn (clavus)[edit | edit source]

Painful focal hyperkeratosis over articular or bony prominences, especially in orthopaedic defects (e.g. hallux valgus)

Pathogenesis[edit | edit source]

Prolonged concentrated pressure against a firm base - the corner taper pin sometimes extends to the painful periosteum.

Clinical image[edit | edit source]

Circular, yellowish lesion, raised, sharply demarcated, sometimes with an indentation in the middle, very painful when walking!

Diferencial diagnosis[edit | edit source]

Pressure blister, veruka

Diagnosis[edit | edit source]

Histology - parakeratosis, hyperkeratosis at margins; mostly typical appearance

Therapy[edit | edit source]

Sometimes difficult, change of shoes, keratolytic ointment

Decubitus[edit | edit source]

Pressure-related ischaemic necrosis - first erythema with maceration - then areas of dry necrosis and ulceration - extends to adipose tissue and muscle

Therapy[edit | edit source]

Methods of moist wound healing, collaboration with surgeon, systematic nursing care


Tattoo[edit | edit source]

Traumatic x decorative - there may be infectious complications, especially pyodermia


Irritation (intertrigo)[edit | edit source]

  • Mechanical friction of skin against skin + chemical influences (sweat) at the site of skin folds
  • Sharply demarcated red, swollen areas, sore, burning
  • Mostly obese persons - often secondary bacterial and yeast infection

Heat causes[edit | edit source]

Frostbite (congelatio)[edit | edit source]

Prone people with blood circulation disorders, acral areas affected - hands, feet, earlobes, tip of nose,...

  1. degree - whitening and then redness of the skin - severe soreness
  2. degree - hemorrhagic blisters
  3. degree - necrosis

Therapy[edit | edit source]

Surgery

Related articles[edit | edit source]


Chilblains (perniones)[edit | edit source]

Skin changes caused by cold - especially skin of the hands - impaired blood circulation, acrocyanosis, increased sweating contribute to the appearance; more common in women

Clinical image[edit | edit source]

  • elevated maculopapules - light red in warmth, reddish blue in cold
  • itching, burning to pain - especially in warmth and with temperature changes
  • at summer without problems, recurring as autumn approaches

Therapy[edit | edit source]

Vasodilators (pentoxifylline), staying warm

Prognosis[edit | edit source]

A chronic illness with winter relapses

Related articles[edit | edit source]


Burns (combustio)[edit | edit source]

A burn injury is damage to the skin from heat (scalding, contact with a heat source or fire), chemicals, electricity or radiation. In children, it is most often heat damage to the skin. In more serious cases, burn disease develops, threatening the patient's life initially with burn shock and later with sepsis.

Degrees of burns[edit | edit source]

  1. degree - erythema
  2. degree - subepidermal blisters
  3. degree - superficial necrosis

Therapy[edit | edit source]

Immediately cool down, corticoid ointment in small degree, in bigger degree system corticoids for a short time, otherwise surgery

Similar to cauterisation (cauterisatio) - worse with lye - collapsing necrosis

Related articles[edit | edit source]


Erythema ab igne[edit | edit source]

Radiant heat (ab igne = from fire) - electric blankets, sitting by the fireplace; reticular erythema, turning into brown hyperpigmentation - thermal melanosis.
The finding is one of the precancers!!!

Related articles[edit | edit source]

Ionizing radiation[edit | edit source]

Acute radiodermatitis[edit | edit source]

A skin disease resulting from exposure to ionizing radiation. In the acute form, redness, swelling, and in more severe cases, blisters appear.

Degrees of radiation exposure[edit | edit source]

3-12 days after exposure (at least 7Gy)

  1. degree - dry skin with hair loss
  2. degree - redness blistering
  3. degree - radiation ulcer - very painful, slow to heal

Therapy[edit | edit source]

Emolients + local corticosteroids

Chronic radiodermatitis[edit | edit source]

The chronic form is characterized by atrophy of the skin, its easy wounding with poorly healing ulcers.

Clinical image[edit | edit source]

Poikilodermia - a circumscribed area of atrophic skin with prominent vascular pattern, sclerotization of connective tissue at high doses, skin easily damaged - poorly healing ulcers

Terapie[edit | edit source]

Emolients + on the ulcer epithelizing ointments with vitamins or hydrocolloids; must be monitored for the possibility of carcinoma

Related articles[edit | edit source]

Links[edit | edit source]

Sources[edit | edit source]

  • Jiří Štork et al. Dermatovenerologie. Galén, Karolinum. 2008
  • presentations on website http://kozni.lf1.cuni.cz
  • lectures of teacher of the Clinic of Dermatovenerology 1.LF UK and VFN
  • Kuba Holešovský, dermatovenerology questions