Let us learn about Disorders of the Parathyroid Hormone.
Due to Hypo Secretion of PTH:
Tetany:
This disease is caused in man due to hypo secretion of PTH. It is more severe in young than older persons and also severe in pregnant condition.
The characteristic features of this disease are:
(i) Morphological features:
1. Carpal spasm or Trousseau’s sign is one of the flexion at the wrist or meta-phalangeal joints (Fig. 12.13).
2. Pedal spasm is the flexion at the ankle or metatarsal joints.
3. Osteoporosis and osteomalacia occur.
4. Dental lesions occur, defects in enamel formation and growth of root.
(ii) Physiological features:
1. Salivation is increased.
2. Increased the rate of excretion of calcium and phosphorus.
3. Causes hypocalcemia by the deficiency of vit. D3.
4. Reduced intestinal uptake of Ca++.
5. Heart rate is increased.
6. Respiration becomes noisy and rapid due to respiratory muscular spasm.
7. Convulsions are most serious effect.
(iii) Psychological features:
1. Irritability, anxiety and depression occur.
2. Shows mental retardation.
Due to Hyper Secretion of PTH:
Over secretion of PTH, shows the following clinical features:
(i) Anatomical features:
1. General weakness in the body.
2. Bones becomes fragile.
3. Formation of cysts and stones in kidney.
4. Loss of muscular tone.
(ii) Physiological features:
1. Renal calcium level is increased due to increased glomerular filtration of Ca++.
2. Development of polyuria due to damage of renal tubule.
3. Loss of appetite.
4. Nausea and vomiting occurs.
5. Reduce intestinal Ca++ uptake.
6. Demineralization of bones.
Special notes:
Laryngismus stridulous:
Due to hypo secretion of PTH, spasm occurs in laryngeal muscles and may cause asphyxia.