Riehl melanosis
Specialty	Dermatology

Riehl melanosis is a form of contact dermatitis, beginning with pruritus, erythema, and pigmentation that gradually spreads which, after reaching a certain extent, becomes stationary.^[1]^: 857 The pathogenesis of Riehl melanosis is believed to be sun exposure following the use of some perfumes or creams (a photocontact dermatitis).^[1]^: 858

Riehl melanosis is named after the dermatologist Gustav Riehl, who first described the condition in 1917.^[2]^[3]

References

^ ^a ^b James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology (10th ed.). Saunders. ISBN 978-0-7216-2921-6.
^ Dorland's Illustrated Medical Dictionary. Philadelphia: Elsevier Saunders. 2012. p. 1647.
^ Ohshiro, T.; Calderhead, R. G. (1995). Laser Treatment for Naevi. Chichester, UK: John Wiley & Sons. p. 37.

Pigmentation disorders/Dyschromia

Hypo-/
leucism

Loss of
melanocytes

Vitiligo	Quadrichrome vitiligo Vitiligo ponctué
Syndromic	Alezzandrini syndrome Vogt–Koyanagi–Harada syndrome
Melanocyte development	Piebaldism Waardenburg syndrome Tietz syndrome

Loss of melanin/
amelanism

Albinism	Oculocutaneous albinism Ocular albinism in humans
Melanosome transfer	Hermansky–Pudlak syndrome Chédiak–Higashi syndrome Griscelli syndrome Elejalde syndrome Griscelli syndrome type 2 Griscelli syndrome type 3
Other	Cross syndrome ABCD syndrome Albinism–deafness syndrome Idiopathic guttate hypomelanosis Phylloid hypomelanosis Progressive macular hypomelanosis

Leukoderma w/o
hypomelanosis

Ungrouped

Hyper-

Melanin/
Melanosis/
Melanism

Reticulated	Dermatopathia pigmentosa reticularis Pigmentatio reticularis faciei et colli Reticulate acropigmentation of Kitamura Reticular pigmented anomaly of the flexures Naegeli–Franceschetti–Jadassohn syndrome Dyskeratosis congenita X-linked reticulate pigmentary disorder Galli–Galli disease Revesz syndrome
Diffuse/ circumscribed	Lentigo/Lentiginosis: Lentigo simplex Liver spot Centrofacial lentiginosis Generalized lentiginosis Inherited patterned lentiginosis in black persons Ink spot lentigo Lentigo maligna Mucosal lentigines Partial unilateral lentiginosis PUVA lentigines Melasma Erythema dyschromicum perstans Lichen planus pigmentosus Café au lait spot Poikiloderma (Poikiloderma of Civatte Poikiloderma vasculare atrophicans) Riehl melanosis
Linear	Incontinentia pigmenti Scratch dermatitis Shiitake mushroom dermatitis
Other/ ungrouped	Acanthosis nigricans Freckle Familial progressive hyperpigmentation Pallister–Killian syndrome Periorbital hyperpigmentation Photoleukomelanodermatitis of Kobori Postinflammatory hyperpigmentation Transient neonatal pustular melanosis

Other
pigments

Iron	Hemochromatosis Iron metallic discoloration Pigmented purpuric dermatosis Schamberg disease Majocchi's disease Gougerot–Blum syndrome Doucas and Kapetanakis pigmented purpura/Eczematid-like purpura of Doucas and Kapetanakis Lichen aureus Angioma serpiginosum Hemosiderin hyperpigmentation
Other metals	Argyria Chrysiasis Arsenic poisoning Lead poisoning Titanium metallic discoloration
Other	Carotenosis Tar melanosis

Dyschromia

See also

References