Hyperpigmentation

Question 1

Causes of Generalised Hyperpigmentation

Answer 1

1. Iron overload in chronic transfusion (e.g. Thalasaemia)
2. Bile pigment accumulation
3. Photosensitity (Exposed area, Drugs, Porphyria)
4. Raised ACTH level
   Addison’s disease, Congenital Adrenal Hyperplasia (Pigments concentrated at mucosa, nipple, umbilicus, genitalia, joint creases and area of friction)
5. Chronic renal failure (look for growth failure, pallor, rickets, hypertension and AV fistulas)
6. Racial
7. General patchy pigmentation (Fanconi anaemia, Porphyria, Liver disease)

Question 2

Photosensitivity causes

Answer 2

1. Skin disease (Photosensitive Dermatitis, Xeroderma Pigmentosa, Albinism and Hypopituitarism)
2. Circulating photosensitizer (Porphyria, Drug - Sulphonamide, tetracycline, Thiazides etc)
3. Systemic disease (SLE, Addison’s disease - often first presented with severe sunburn after outing)

Question 3

Local pigmentation causes

Answer 3

1. Mongolian Spot - Benign
2. Neurodermatosis - NF and TS
3. Syndromes
   McCune Albright Sx - Unilateral pigment and precocious puberty + cystic bone lesion
   Peutz Jegher Sx - Pallor + pigment at lip/ Palmer surface of digit + intestinal polyposis, AD
   Xeroderma Pigmentosa
   Urticaria Pigmentosa
4. Pigmented Navi - Freckle

Question 4

Neurofibromatosis Type 1 Diagnostic Criteria

Answer 4

Chrom 17
Criteria: 
A. >2 of the following:
> 6 significant cafe au lait spots (>5mm prepubertal and 15mm in adults)
>2 Neurofibroma
Axillary / Inguinal freckle
>2 Iris Harmatoma
Optic Glioma
B. FH present
C. XR bone show distinct cortical lesion

Question 5

Neurofibromatosis Type II Diagnostic Criteria

Answer 5

Chrom 22
Either bilateral Acoustic Neuroma
OR: 1st degree relative with Type II disease and either unilateral acoustic neuroma
OR: Neurofibroma / Glioma/ Schwannoma/ Meningioma/ Subcapsular Lenticular opacity

Question 6

Steps in clinical examination of Hyperpigmentation

Answer 6

1. Note the dark complexion
2. Check if parents same colour (Racial)
3. Note the distribution of pigment
4. Note if any facial features (Cooley’s face; Pallor; Jaundice; Cafe au lait)
5. Examinatin of hands and UL (Liver palm; Nail dystrophy, AV fistual; Drip site and Radial defect -Fanconi Anaemia)
6. Abdominal examination (Only sun exposed area - photosensitivity e.g. SLE; Addisons - Mucosa, nipple, skin crease and genitalia)
7. Measure BP