Color Change of the Skin (Macula): Or something else? Differential Diagnosis

Congenital malformations, deformities, and chromosomal abnormalities (Q00-Q99).

  • Albright syndrome – combination of fibroplasia, pigmentary abnormalities (café-au-lait spots (CALF); light brown macules/spot), and endocrine hyperfunction.
  • Neurofibromatosis – genetic disease with autosomal dominant inheritance; belongs to the phakomatoses (diseases of the skin and nervous system); three genetically distinct forms are distinguished:
    • Neurofibromatosis type 1 (von Recklinghausen’s disease) – patients develop multiple neurofibromas (nerve tumors) during puberty, which often occur in the skin but also occur in the nervous system, orbita (eye socket), gastrointestinal tract (gastrointestinal tract), and retroperitoneum (space located behind the peritoneum on the back toward the spine); Typical is the appearance of café-au-lait spots (light brown macules) and multiple benign (benign) neoplasms
    • [Neurofibromatosis type 2 – characteristic is the presence of bilateral (bilateral) acoustic neuroma (vestibular schwannoma) and multiple meningiomas (meningeal tumors).
    • Schwannomatosis – hereditary tumor syndrome]
  • Peutz-Jeghers syndrome (synonyms: Hutchinson-Weber-Peutz syndrome or Peutz-Jeghers hamartosis) – rare, genetic and autosomal-dominant inherited gastrointestinal polyposis (occurrence of numerous polyps in the gastrointestinal tract) with characteristic pigmented patches on the skin (especially in the middle of the face) and mucous membranes; clinical presentation: Recurrent (recurrent) colicky abdominal pain; iron deficiency anemia; blood accumulation on stool; possible complications: Ileus (intestinal obstruction) due to invaginations of a polyp-bearing intestinal segment.

Skin and subcutaneous (L00-L99).

  • Berloque dermatitis – skin alteration due to chemical photosensitization; later, permanent pigment spots develop.
  • Chloasma (melasma) – circumscribed hyperpigmentation that occurs on the face; yellowish to brownish macules.
  • Nevi:
    • Dermal melanocytic nevi (pigment nevi).
      • Mongolian spot – indistinct gray-blue discoloration of the skin in the buttock/back area; regresses by puberty; usually seen in mongolians
      • Nevus coeruleus (blue nevus) – coarse blue-black nodules that appear mainly on the back of the hand or arm.
      • Naevus fusco-coeruleus – blurred flat blue-black pigmentation in the area of the face (naevus Ota; synonym: oculodermal melanocytosis)/shoulder (naevus Ito); possibly with hypertrichosis (increased body and facial hair; without a male distribution pattern); occurs in Mongolians and Japanese.
    • Epidermal melanocytic nevi – refers to marks characterized by a sharply demarcated brown patch.
      • Café-au-lait spot (nevus pigmentosus).
      • Ephelides (freckles)
      • Lentigines (lentigo simplex)
      • Melanosis naeviformis (Becker’s nevus) – extensive brown colored skin area, which occurs in combination with hypertrichosis (increased body and facial hair; without a male distribution pattern).
      • Nevus spilus – combination of café-au-lait spots (CALF) and small-spotted pigment cell nests.
    • Nevus cell nevus (NZN) – marks that pass through the following stages.
      • Junctional nevus – sharply demarcated spot/dot-shaped marks that are homogeneously brown(-black) in color.
      • Compound nevus – sharply demarcated, usually nodular brown(-black) marks, often with a fissured surface; hypertrichosis may accompany; usually form from junctional nevi
      • Dermal nevi – papular brown marks with hair trimming.
  • Nevus anaemicus – refers to a bright spot with a jagged outline; due to permanent constriction (“constriction”) of the dermal vessels (skin vessels).
  • Pityriasis alba – brittle scaly skin that occurs mainly on the face; bright macules on sebaceous gland-rich areas of the chest and back.
  • Stretch marks (striae gravidarum); initially bluish-reddish, later whitish-yellowish stripes, mainly on the abdomen, buttocks and thighs.
  • Tinea nigra: Schwärzepilz ( Hortaea werneckii) – light brown, uniformly pigmented macules.
  • Vitiligo (white spot disease)

Infectious and parasitic diseases (A00-B99).

  • Erysipelas (erysipelas) – nonpurulent skin infection caused predominantly by ß-hemolytic group A streptococci (Streptococcus pyogenes); in hemorrhagic erysipelas, scarring may occur after the blister zone heals, resulting in permanent brownish skin discoloration due to incorporated hemosiderin (heme = red blood substance)
  • Leprosy (small hypopigmented macules).
  • Measles (maculopapular exanthema – blotchy rash appearing with small nodules; spreads from the head to the limbs; appears from about the third day.
  • Pityriasis versicolor (Kleienpilzflechte, Kleieflechte) – non-inflammatory superficial dermatomycosis (skin fungal disease) caused by the pathogen Malassezia furfur (yeast fungus); sun exposure causes a whitish discoloration of the affected areas (white macules/spots).
  • Rubella (small-spotted exanthema (rash), which begins on the face and spreads over the body; persists for one to three days).
  • Syphilis (light to brown-red, blotchy exanthema (rash) all over the body, without itching).
  • Nonspecific viral exanthema – rash due to unspecified viral infection.

Neoplasms – tumor diseases (C00-D48).

  • Benign juvenile melanoma (spindle cell nevus; Spitz tumor) – circumscribed benign nodular marks occurring in children/adolescents.
  • Dysplastic nevus (atypical nevus, active nevus) – acquired nevus cell nevus with outgrowths, irregular pigmentation/color changes, increase in size, signs of inflammation.
  • Lentigo maligna (synonyms: Melanoma in situ, melanotic precancerosis, melanosis circumscripta praeblastomatosa Dubreuilh, Dubreuilh’s disease or Dubreuilh’s disease) – intraepidermal (located in the epidermis) neoplastic proliferation (new formation) of atypical melanocytes (cells that form the skin pigment melanin).

Drugs

Other causes

  • Allergy, unspecified
  • Post-inflammatory hypo/hyperpigmentation.