Depigmentation

Question 1

Causes of Generalised Depigmentation

Answer 1

1. Familial
2. Albinism
3. PKU
4. Hypopituitarism (Lack of melanocyte stimulating hormone)
5. Chediak- Higashi Syndrome (AR, Anaemia, Low Platelet and WBC, Recurrent infection, Hepatosplenomegaly, Lymphadenopathy and Partial Albinism)
6. Kwashiorkor
7. Ectodermal Dysplasia (Nail, teeth Dystropy)
8. Menkes’ Kinky hair syndrome (typical twisted hair)

Question 2

Steps in Clinical examination in GeDepigmentation

Answer 2

1. White hair suggests Albinism, PKU or Chediak-Higashi Syndrome.
   Dark hair suggests Hypopituitarism / Menky Kirky Hair Syn
2. Short obese child in Hypopituitarism (mid line defects)
3. Eczema in PKU, peculiar smell of phyeylalanine
4. Mentally retarded child (PKU)
5. Eye - Pink iris, myopia, photophobia (wearing dark glasses) - Albinism
6. Look for midline defects - Cleft lip and palate Hypotelorism and Blindness in septo-opitc dysplasia

Question 3

Causes of Localised Depigmentation

Answer 3

1. Vitiligo (Assoc with Addison’s disease, DM, Hypothyroidism and Pernicious Anaemia)
2. Syndromes (TS and Piebaldism (assoc with Waadenburg’s Syndrome)
3. Dermatological
   Chronic Skin: Eczema, post infection, Pityriasis Alba
   Infections: Pityriasis Vesicolor
   Halonaevus

Question 4

Clinical examination for Localised Depigmentation

Answer 4

1. Hypopigmented suggests Tuberous Sclerosis (check if Scaly, Leafy edge) then look for Adenoma Sebaceum and other features of TS
2. Completely depigmented spots suggest Vitiligo and Piebaldism
3. Look for white forelock and heterochromia —> Waldenberg’s Syndrome
4. Look for evidence of Hypothyroidism (goitre)
5. Lying and standing BP to exclude Addison’s
6. Test Mentality and Hearing