Related Experiment Video
Updated: May 5, 2026

Quantification of Hypopigmentation Activity In Vitro
Published on: March 6, 2019
Pigmentation disorders: hyperpigmentation and hypopigmentation
Electra Nicolaidou1, Andreas D Katsambas
11st Department of Dermatology, University of Athens School of Medicine, "Andreas Sygros" Hospital, 5 I. Dragoumi str, GR-16121, Athens, Greece.
Abstract:
Pigmentation disorders include a large number of heterogeneous conditions that are usually characterized by altered melanocyte density, melanin concentration, or both, and result in altered pigmentation of the skin. Some of these disorders are extremely common (melasma, vitiligo), whereas others are rare. In this contribution, we review the most common pigmentation disorders that appear on the face. These lesions, even though mostly asymptomatic, have a great impact on a patient's quality of life.
Related Concept Videos
Skin Diseases and Disorders
Gram-positive Staphylococcus spp. and Streptococcus spp. are responsible for many of the most common skin infections. However, many...
Changes in Skin Color: Clinical Perspectives
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Pigmentation
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
Disorders of Erythrocytes
Erythrocyte disorders can be broadly categorized into two main types: anemic and polycythemic conditions.
A low oxygen-carrying capacity of the blood due to the loss, lower production, or destruction of erythrocytes is termed anemia. Hemorrhagic anemia, for example, occurs when bleeding from an external wound or internal ulcer reduces erythrocyte counts.
On the other...
Hypothyroidism II: Pathophysiology

