Endocrinology MCQ : 1-3 : Answers

  • Diabetic amyotrophy is painful asymmetrical proximal motor neuropathy affecting the lower limbs (Less commonly it is symmetrical)
  • It is an example of a multiple mononeuropathy; the onset is often associated with poor diabetic control and may improve with good control.
  • It is thought to be caused by the occlusion of the vasa nervorum of the proximal lumbar plexus and/or the femoral nerve causing infarction.
  • The initial presentation is with pain in the thigh. This is followed by wasting and weakness of the quadriceps and loss of the knee jerk.

  • The tricyclic antidepressants amitriptyline and nortriptyline  are the drugs of choice for painful diabetic neuropathy
  • amitriptyline is given in a dose of 25–75 mg daily (higher doses under specialist supervision).
  • Other classes of antidepressants do not appear to be effective.
  • Gabapentin is licensed for the treatment of neuropathic pain and is an effective alternative to a tricyclic antidepressant.

  • The factors leading to the development of peripheral neuropathy in diabetes
    1. Polyol pathway (Hyperglycemia -->Accumulation of sorbitol -->decreased membrane Na+/K+ -ATPase activity-->structural breakdown of nerves-->causing abnormal action potential propagation)
    2. Advanced glycation end products (AGE)
    3. Oxidative stress : direct damage to blood vessels leading to nerve ischemia and facilitation of AGE reactions. Despite the incomplete understanding of these processes, use of the antioxidant alpha lipoic acid may hold promise for improving neuropathic symptoms

  • Autonomic failure involves both the parasympathetic and sympathetic systems, however it is failure of the sympathetic system which produces most symptoms.
  • Classically the patient is a middle-aged male who complains of impotence, inability to sweat and postural blackouts when standing up.
  • The main aim of treatment is to manage the postural hypotension:
    • sleep slightly head up -->stimulates renin release –> prevents the excessive sodium and fluid loss
    • fludrocortisone - low dose e.g. 0.1 mg/day
    • intranasal DDAVP –> reduce nocturnal fluid loss
    • vasopressors - may cause recumbent hypertension
    • elastic support stocking may help

  • Hyperosmolar hyperglycemic state (HHS) most commonly occurs in old patients with type 2 diabetes mellitus who have some concomitant illness that leads to reduced fluid intake.
  • The condition is characterized by hyperglycemia, hyperosmolarity, and dehydration without significant ketoacidosis
  • This condition is differentiated from DKA on the basis of:
    • Very high blood glucose (> 30mmol/l) but only a trace or +1 ketones in plasma or urine
    • Very high plasma osmolality (>350 mosmol/kg). The normal range is 280-300 mosmol/kg.

osmolality = 2(Na+K) + urea + glucose

  • DKA : The overall mortality rate is 2% or less currently

  • HHS : The overall mortality rate is between 10% and 20% and is dependent on coexisting conditions and complications

  • For management Lower doses of insulin are required because there is greater insulin sensitivity (Not like DKA)

  • Complications

    • Ischemia or infarction to any organ, including the heart and brain
    • Hypoglycemia
    • Hypokalemia
    • Cerebral edema (rare)
    • Thromboembolism
    • Rhabdomyolysis

Acromegaly : is an abnormal enlargement of the extremities of the skeleton caused by hypersecretion of the pituitary growth hormone after epiphysial fusion. growth hormone hypersecretion occurs after puberty and the growth plates have fused so that only flat bone enlargement and soft tissue growth is possible. Generalized visceromegaly occurs, including cardiomegaly, macroglossia, and thyroid gland enlargement,This is due to a pituitary tumour in almost all cases ,Headaches and visual field defects are the most common symptoms. Visual field defects depend on which part of the optic nerve pathway is compressed.The most common manifestation is a superior bitemporal hemianopsia due to pressure on the optic chiasm from below .
Acromegaly Diagnosis can be made from the characteristic clinical findings. CT, MRI, or skull x-rays disclose cortical thickening, enlargement of the frontal sinuses, and enlargement and erosion of the sella turcica. X-rays of the hands show tufting of the terminal phalanges and soft-tissue thickening. Generally, glucose tolerance is abnormal and serum phosphate levels are mildly elevated.


>>>> Post your Answer Here ????

Design by Up2date.us