Written and peer-reviewed by physicians—but use at your own risk. Read our disclaimer.

banner image

amboss

Trusted medical answers—in seconds.

Get access to 1,000+ medical articles with instant search
and clinical tools.

Try free for 5 days

Collection of dermatological disorders

Last updated: January 18, 2021

Summarytoggle arrow icon

This article covers various dermatological disorders, including sebaceous and epidermoid cysts, cat scratch disease, cutaneous mastocytosis, miliaria, nummular eczema, angiokeratoma, dyshidrotic eczema, livedo reticularis, xeroderma pigmentosum, pseudofolliculitis barbae, and albinism.

References:[1][2][3]

[7][8]

Types of miliaria
Miliaria crystallina Miliaria rubra Miliaria profunda
Epidemiology
  • Most common type
  • Usually seen in adult men in tropical climates, who have had repeated episodes of miliaria rubra
Level of sweat duct blockage
Clinical features
  • Clear 1–2 mm vesicles with no erythema

  • Callus: thick, toughened skin caused by repeated mechanical pressure and friction
  • Clavus: a painful, hyperkeratotic lesion with a center core (corn) caused by frictional forces and trauma

  • Description: chronic facial dermatitis affecting the perioral region
  • Epidemiology: primarily children and women 20–45 years of age [15]
  • Etiology
    • Unknown
    • Presumably caused by regular application of (glucocorticoid) creams and/or cosmetics
  • Clinical features
    • Erythema with grouped papules and pustules
    • Dry skin with painful burning and a sensation of tightness
    • No residual scarring after resolution
  • Treatment
  • Description: a rheumatological, spondylarthritic disease with simultaneous occurrence of synovitis, acne, pustulosis, hyperostosis, and osteitis
  • Clinical features
  • Etiology: unknown
  • Diagnostics
  • Treatment: primarily symptomatic

Types of livedo reticularis [16]
Physiological livedo (idiopathic livedo) Pathological livedo (livedo racemosa)
Definition
  • A vascular syndrome that can be caused by either benign autonomic dysregulation of cutaneous perfusion or pathological obstruction of blood vessels
Epidemiology/etiology
Pathophysiology
  • Autonomic dysregulation (functional disturbance) causing slowed cutaneous perfusion in response to external factors (i.e., cold)
  • Localized obstructions slow the blood flow (organic disturbance)
Clinical features
  • Symmetrical livedo reticularis (regular, small, round) of the extremities and sometimes the trunk
  • Triggered by cold, regresses after application of warmth
Treatment
  • Warmth, sauna, alternating cold and warm baths
  • Treat the underlying disease
Prognosis
  • Improves with age
  • Depends on the underlying disease (usually more difficult to treat)

Livedo reticularis that does not regress after application of warmth is indicative of an underlying vascular disease and requires treatment.

  • Description
    • Rare, autosomal-recessive, hereditary skin disease caused by defective DNA repair mechanisms (i.e., nucleotide excision repair) [17]
    • In affected individuals, minimal UV radiation can lead to severe skin damage and has carcinogenic effects
  • Clinical features
  • Management
    • Protection from light and avoidance of sun exposure
    • Frequent skin cancer screening, retinoids as prophylaxis
  • Prognosis: severely limited life expectancy [18]

  • Description: inflammatory skin reaction in response to short hair that becomes entrapped within the skin
  • Etiology
    • Usually occurs due to shaving (also known as razor bumps)
    • Most common in African American men because the hair shafts typically form tight coils
  • Pathophysiology
    • Extrafollicular penetration: Hair enters the interfollicular epidermis after it exits the follicular orifice.
    • Transfollicular penetration: Hair penetrates the dermis before exiting the follicular orifice.
  • Clinical features
  • Diagnostics: a clinical diagnosis
  • Treatment
    • Cessation of shaving
    • Alternative hair-removal techniques (e.g., laser hair removal)
    • Adjunctive: topical treatments (e.g., retinoids, corticosteroids, antimicrobials)

  • Definition: a rare, very aggressive vascular malignancy, arising from endothelial cells of blood or lymphatic vessels [19]
  • Epidemiology: peak incidence age > 70 years [19]
  • Etiology [19]
  • Clinical features [20][21]
    • Location
      • More common in sun-exposed areas
      • Usually occur on the head, neck, and breast
      • May involve the internal organs (e.g., hepatic angiosarcoma)
    • Lesion
      • Blue/purple-colored with a bruise-like appearance
      • Later stage: hemorrhage or ulceration
      • High variability in appearance
  • Treatment [21]
    • Complete resection with wide margins
    • Resection may be complicated by the aggressive course of the disease and delayed diagnosis.
  1. Singh V. General Anatomy. Elsevier Health Sciences ; 2015
  2. Cutaneous Cysts. https://www.msdmanuals.com/professional/dermatologic-disorders/benign-skin-tumors,-growths,-and-vascular-lesions/cutaneous-cysts. Updated: January 1, 2018. Accessed: April 27, 2018.
  3. Sangueza OP, Moradi S, Mansoori P, et al.. Dermatopathology Primer of Cutaneous Tumors. CRC Press ; 2015
  4. Opavsky MA. Cat scratch disease: The story continues.. The Canadian journal of infectious diseases = Journal canadien des maladies infectieuses. 1997; 8 (1): p.43-9. doi: 10.1155/1997/982908 . | Open in Read by QxMD
  5. Berzigotti A, Magalotti D, Zappoli P, Rossi C, Callea F, Zoli M. Peliosis hepatis as an early histological finding in idiopathic portal hypertension: A case report.. World journal of gastroenterology. 2006; 12 (22): p.3612-5. doi: 10.3748/wjg.v12.i22.3612 . | Open in Read by QxMD
  6. Atila K, Coker A, Uçar D, et al. A rare clinical entity misdiagnosed as a tumor: peliosis hepatis.. Ulusal travma ve acil cerrahi dergisi = Turkish journal of trauma & emergency surgery : TJTES. 2007; 13 (2): p.149-53.
  7. Bleibel W, Curry MP. Peliosis Hepatis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/peliosis-hepatis.Last updated: June 27, 2017. Accessed: September 14, 2017.
  8. Hepatic Peliosis. https://radiopaedia.org/articles/hepatic-peliosis. Updated: September 14, 2017. Accessed: September 14, 2017.
  9. Wenzel FG, Horn TD. Nonneoplastic disorders of the eccrine glands.. J Am Acad Dermatol. 1998; 38 (1): p.1-17; quiz 18-20. doi: 10.1016/s0190-9622(98)70532-8 . | Open in Read by QxMD
  10. Fernández-Crehuet P, Ruiz-Villaverde R. Pitted keratolysis: an infective cause of foot odour.. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne. 2015; 187 (7): p.519. doi: 10.1503/cmaj.140809 . | Open in Read by QxMD
  11. Taïeb A, Plantin P, Du Pasquier P, Guillet G, Maleville J. Gianotti-Crosti syndrome: a study of 26 cases.. Br J Dermatol. 1986; 115 (1): p.49-59. doi: 10.1111/j.1365-2133.1986.tb06219.x . | Open in Read by QxMD
  12. Chuh A, Lee A, Zawar V. The diagnostic criteria of Gianotti-Crosti syndrome: are they applicable to children in India?. Pediatr Dermatol. undefined; 21 (5): p.542-7. doi: 10.1111/j.0736-8046.2004.21503.x . | Open in Read by QxMD
  13. Wiechers T, Rabenhorst A, Schick T, et al. Large maculopapular cutaneous lesions are associated with favorable outcome in childhood-onset mastocytosis.. J Allergy Clin Immunol. 2015; 136 (6): p.1581-1590.e3. doi: 10.1016/j.jaci.2015.05.034 . | Open in Read by QxMD
  14. Tolaymat L, Hall MR. Perioral Dermatitis. StatPearls. 2020 .
  15. Sajjan V, Swamy M, Lunge S, Pandit A. Livedo reticularis: A review of the literature. Indian Dermatology Online Journal. 2015; 6 (5): p.315-321. doi: 10.4103/2229-5178.164493 . | Open in Read by QxMD
  16. Xeroderma pigmentosum. https://rarediseases.org/rare-diseases/xeroderma-pigmentosum/. . Accessed: December 17, 2020.
  17. Lucero R, Horowitz D. Xeroderma Pigmentosum. StatPearls. 2020 .
  18. Angiosarcoma - National Cancer Institute. https://www.cancer.gov/pediatric-adult-rare-tumor/rare-tumors/rare-vascular-tumors/angiosarcoma. Updated: February 27, 2019. Accessed: April 6, 2020.
  19. Gaballah AH, Jensen CT, Palmquist S, et al. Angiosarcoma: clinical and imaging features from head to toe. Br J Radiol. 2017; 90 (1075): p.20170039. doi: 10.1259/bjr.20170039 . | Open in Read by QxMD
  20. Tambe SA, Nayak CS. Metastatic Angiosarcoma of Lower Extremity.. Indian dermatology online journal. undefined; 9 (3): p.177-181. doi: 10.4103/idoj.IDOJ_92_17 . | Open in Read by QxMD
  21. Kettelhut EA, Traylor J, Roach JP. Erythema Ab Igne. StatPearls. 2020 .