[C] 1.34. Pathologic pigmentation caused by porphyrins

Question 1

Porphyrin

Answer 1

• Haem synthesis
• Affinity to bone
• Photosensitisation
• Brown-violet & fuoresence under UV light
• Can be hereditary

Question 2

Porphyrin as a component of Hb

Answer 2

Protoporphyrin + Fe + globulin = Hb

Question 3

Where is porphyrin synthesised?

Answer 3

Liver & BM

Question 4

Porphyrin excretion

Answer 4

Excreted with urine & faeces:

• Uroporphyrin
• Coproporphyrin

Question 5

Porphyrin toxicosis causers

Answer 5

• Lead
• Arsenic
• CCl₄
• Benzene
• Anilin

Question 6

Characteristics of porphyria

Answer 6

• Spongy bones are coloured
• Dental cement brown
• Dentin pink, reddish brown
• Enamel: White
• Cartilage, ligaments & tendons: Uncoloured