Ehlers-Danlos Syndrome (EDS)

20/02/2010

genetic disorder that results in a defect in collagen synthesis. The severity may range from mild to life-threatening. Common symptoms include extremely flexible joints, eye lens dislocation, and bone deformities. Joints have a high tendency to dislocate.


Adrenomyeloneuropathy

01/02/2010

A progressive degenerative disorder of the myelin sheathing of the spinal cord.

a varient of adrenoleulkodystrophy.

disorder can cause adrenal insufficiency and hypogonadism in addition to neurological symptoms

Biochemistry:

disorder of the peroxisomes, (intracellular organelles responsible for a variety of biochemical reactions) the most important being the oxidation of VLCFAs, biosynthesis of bile acids and glycoxylate detoxification.

People with adrenoleukodystrophy and adrenomyeloneuropathy do not produce fatty acylcoenzyme A (acyl-CoA) synthetase, which breaks down VLCFAs in the first step in their oxidation.

VLCFAs accumulate and form cytoplasmic inclusions, which leads to progressive dysfunction in the nervous system, adrenal glands and testes, all of which are sites of VLCFA metabolism.

Etiology:

characterized by the accumulation of very-long-chain fatty acids in plasma, the central and peripheral nervous systems, adrenal glands and testes, which leads to dysfunction of these organs and systems.

X-linked genetic disorder,  the gene is located on the long arm of the X chromosome (Xq28)

Management:

 limited and includes hormonal replacement therapy for concomitant adrenal insufficiency or hypogonadism, or both.

dietary goals:

to decrease the exogenous sources of VLCFA by instituting a low-fat diet; however, dietary modifications have not been consistently shown to prevent or slow the course of the disease.

Administration of monounsaturated fatty acids leads to competitive inhibition between saturated and unsaturated fatty acid precursors in the microsomal elongation pathway, thereby leading to a reduction in endogenous VLCFA synthesis.

Khandwala, Hasnain M, Spurek, Monika,Taylor-Gjevre,  Regina,  and Van Uum, Stan. 2004. Adrenomyeloneuropathy as a cause of primary adrenal insufficiency and spastic paraparesis. CMAJ. 171:9. Retrieved February 1, 2010 from http://www.cmaj.ca/cgi/content/full/171/9/1073


Maple syrup urine disease (branched-chain ketoaciduria)

29/01/2010

an autosomal recessive metabolic disorder.

Etiology:

 inability of the body to properly break down branched-chain amino acids (leucine, isoleucine and valine)

due to a deficiency of the branched-chain alpha-keto acid dehydrogenase complex

resulting in accumulation of these amino acids and metabolites to toxic levels within the body

Manifestations:

  • presence of sweet-smelling urine
  • poor feeding
  • vomiting
  • dehydration
  • lethargy
  • hypotonuria
  • seizures
  • ketoacidosis
  • opisthotonus
  • pancreatitis
  • neurological decline

Treatment:

  • monitoring of blood chemistry levels
  • diet low in the amino acids valine, leucine and isoleucine


Hirschsprung’s Disease (congenital aganglionic megacolon)

28/01/2010

 

congenital condition in which a section the colon is aganglionic

there is little urge to defecate so the feces accumulate.

  • genetic defect on Chr 10
  • 1/5000 live births
  • Sigmoid colon typically affected

 

  Mechanism:

  • absence of ganglia in parts of the colon
  • no peristalsis occurs in affected region
  • contents accumulate
  • colon becomes distended, in turn results in distended abdomen
  • bowel obstruction may occur

 

Treatment:

  • Surgical exision of aganglionic region

Inflammatory Bowel Disease

08/01/2010

 

Two chronic disorders:


1.Crohn`s disease
2.Ulcerative Colitis

Etiology:

Genetic susceptibility (no gene yet identified): Intolerance of normal gut flora by the body`s immune system.
Immune response is unregulated.

  1. Ulcerative Colitis
  • Chronic inflammation of the colon that produces ulcers in its lining
  • region of affected gut is continuous

 2. Crohn`s Disease

  • A chronic form of inflammatory bowel disease that usually affects the lower small intestine (called the ileum) or the colon
  • skip lesions in small and large intestine

 

Differentiating Characteristics of Crohn`s Disease and Ulcerative Colitis

Characteristics Crohn`s Disease Ulcerative Colitis
Type of inflammation Granulomatous Ulcerative and exudative:
Level of involvement submucosa mucosa
Area of involvement Ileum, colon Rectum and left colon
Extent of Involvement skip lesions in small and large intestine region of affected gut is continuous
Diarrhea common common
Rectal bleeding rare common
Fistuals common rare
Stricture common rare
Perianal abscesses Common Rare
Development of cancer Uncommon Relatively Common

 

Martin, Glenn and Porth, Carol, Mattson. 2009. Pathophysiology Concepts of Altered Health States. 8th ed. Lippincott Williams and Wilkins. Philadelphia


Diabetes Management

15/12/2009

 

Normal Blood Sugar

 

4-6 mmol/l

 

Hypoglycemia

 

<4mmol/L

 

  • pallor

  • cool, moist skin

  • anxiety

  • restlessness

  • tingling in hands, feet tongue

  • confusion

  • drowsy

  • nausea

 

Hyperglycemia

 

>7mmol/L

 

  • drowsy

  • confused

  • dry skin

  • nausea

  • headache

  • vomiting

Common Types of Insulin

 

Humulin R

Toronto

Short-acting

Humulin N

NPH

Intermediate

Glargine/LantusLong-acting

onset 30-60 min

peak: 15-30min

duration 30-60 min

Onset:1-2h

Peak:4-12h

Duration:18-24h

Onset:3-4h

Peak:none

Duration: 24h

  • administered 30 prior to the first meal of the day

  • a second dose may be given before the evening meal or @ HS

  • may only be given Sub Q

  • may be given IV or subcutaneously

Do not mix

 

Glargine/

Lantus

Long-acting

Onset:3-4h

Peak:none

Duration: 24h


Cerebrovascular Accidents (Strokes)

27/11/2009

Ischemic Stroke: sudden loss of function resulting from disruption of the blood supply to a part of the brain. Neurons die when they can no longer maintain aerobic respiration.

  • Event usually the result of long-standing cerebrovascular disease
  • early Tx results in fewer symptoms and less functional loss

5 different types

  1. large thrombosis – 20%
  2. small penetrating artery thrombosis – 25%
  3. cardiogenic embolic stroke – 20%
  4. cryptogenic 30%
  5. Other – 5%

Large artery thrombosis strokes: due to atherosclerotic plaques in the large blood vessels of the brain. Thrombus formation and occlusion at the site af the atherosclerosis result in ischemia and infarction.

Small Penetrating artery thrombotic strokes: affect one or more vessels and are the most common type of ischemic stroke.

Aka lacunar strokes because of the cavity that is created once the infarcted brain tissue disintegrates.

Cardiogenic embolic strokes: are associated with cardiac dysrhythmias, usually atrial fibrillation. Emboli originate from the heart and circulate to the cerebral vasculature, most commonly the left middle cerebral artery, resulting in a stroke. Embolic strokes may be prevented by the use of anticoagulation therapy in patients with atrial fibrillation.

The 2 remaining categories of ischemic strokes are cryptogenic with no known cause and others causes such as cocaine, coagulopathies, migraine and spontaneous dissection of the carotid or vertebral arteries.

Pathophysiology:

Martin, Glenn and Porth, Carol, Mattson. 2009. Pathophysiology Concepts of Altered Health States. 8th ed. Lippincott Williams and Wilkins. Philadelphia