[B] 1.40 Pathological calcification

Question 1

Physiological calcification

Answer 1

Bones and teeth

• Ca-phosphate : Ca Carbonate = 9:1
  
  • Can be reduced (Vit. D deficiency: Ricketts)
  • or enhanced (bone hypertrophy)

Question 2

Pathological calcification

Answer 2

Where it should not be

• Secondary (dystrophic) - after certain changes in the tissues
• Primary (metastatic) - Due to hypercalcaemia

Question 3

Pathological calcification: Appearance

Answer 3

• Gritty feel
• Fine greyish-white granules
• Crepitates when cut
• Stone-hard appearance
  
  • Petrification

Question 4

Pathological calcification: Histological investigation

Answer 4

• HE
  
  • Dark-blue
  • Fine granulation
• Kossa’s staining
  
  • Black (AgPO₃)

Question 5

Secondary (dystrophic) calcification

Answer 5

Frequent in tissues, where regressive/circulatory changes are present

• Infarcts, old necrotic foci, bacterial foci (TB), necrotic muscle fibres, chronic inflammation of bile ducts

Question 6

Causes of increased calcification process

Answer 6

• Reduced circulation
• Alkalosis (pH higher than normal)
• Stopped cellular respiration (decreased CO₂ level)
• Fall in the protective colloids
• Increased phosphatase activity

Question 7

What is shown?

Answer 7

Renal cortical (ischemic) necrosis & mineralisation:

Mineralisation (*) between the necrotic and normal tissue

Question 8

Secondary calcification

Answer 8

• Atherosclerosis (Lipids in the wall of the blood vessels)
  
  • FA + Ca salts = Calcium-soap
• Local fat necrosis - Calcificatio
• Calcification of tubular epithelial cells + excreted by intestinal glands

Question 9

Primary (metastatic) calcification

Answer 9

• Due to hypocalcaemia
  
  • Generalised disorder of calcium salt metabolism
• Predisposing factors
  
  • D-hypervitaminosis, renal failure, local alkaline pH, tumours
• Lime-metastasis (from bone to other tissues)
  
  • Hormonal imbalance (High parathormone)
  • Vit. D overdose
  • Lysis of the bones