Clostridium difficle (C. difficile)

31/03/2009

 Clostridium difficile, ( C. difficile) is a bacterial species normally found in the human bowel. Illness results when this c_difficilenormal stain either mutates in response to antibiotic treatment the individual is taking, or through cross contamination. Cross contamination occurs when the individual contracts a mutant strain of C. difficle from a contaminated surface, object or another individual ill with C. difficile.

The use of antibiotics is the most common method of contracting C. difficile diarrhea and collitis (inflammation and irritation of the colon). This is due to the fact that the antibiotics taken by the individual also target some susceptible good bacterial strains resident in the individual’s bowel.

The death of a large quantity of good helpful bacteria in the human bowel, upsets the normal healthy balence of the bacterial populations within the bowel. This decrease in the levels of good bacterial leaves the bowel open to be populated by increased numbers of unhealthy bacteria. Additionally, this leaves the bowel open to be populated by colonrectummutant strains of harmful bacteria such as C. Difficile.

In individuals with health complications, compromised immune systems and those weakened by pre-existing disease may at risk to severe complications, such as extreme dehydration and in some cases, infection can be fatal. C. Difficle is often hospital or health care facility associated and acquired. Proper hand-washing is extremely effective in the prevention of C. difficile transmission.

 

 

The symptoms of C. difficile include:

  • watery diarrhea (at least three bowel movements per day for two or more days);

  • fever;

  • loss of appetite;

  • nausea; and

  • abdominal pain or tenderness.

Health Canada. 2009. C. Difficile (Clostridium difficile). Retrieved March 31, 2009 from http://www.hc-sc.gc.ca

 

Kelly, Ciarian, P, LaMont, Thomas, J, and Pothoulakis, Charalabos. 1994. Clostridium difficile colitis. The New England Journal of Medicine. 330: 257-262.


Otitis media

30/03/2009

Otitis media is a condition affecting the middle ear. It is caused by inflammation and infection of the middle ear canal. the-human-ear

 Middle ear:

behind tympanic membrane

  • contains 3 auditory ossicles: maleus, incus, stapes

  • maleus articulates with tympanic membrane

  • stapes articulates with the oval window

This condition may result in hearing loss as severe damage occurs and scar tissue accumulates as a result of recurrent severe improperly or untreated infections and inflammation of the middle ear. Individuals may be especially prone to hearing loss or impairment when the infection or inflammation affects the bones of the ear as they are instrumental in conveying sounds waves. 

Hearing:

 

  • sound is generated by waves transduced into energy

  • sound waves into auditory canal

  • tympanic memebrane will be impacted by sound

  • transmits from membrane to maleus

  • waves are converted to mechanical force by bones

  • then transmitted to cochlear

  • sound waves transmitted into fluid filled chamber of cochlea

  • fluid waves move hair cells

 

  1. The outer part of the ear collects sound.

  2.  That sound pressure is amplified through the middle portion of the ear and, in land animals, passed from the medium of air into a liquid medium.

  3. The change from air to liquid occurs because air surrounds the head and is contained in the ear canal and middle ear, but not in the inner ear.

  4. The inner ear is hollow, embedded in the temporal bone, the densest bone of the body.

  5. The hollow channels of the inner ear are filled with liquid, and contain a sensory epithelium that is studded with hair cells.

  6. The microscopic “hairs” of these cells are structural protein filaments that project out into the fluid. mechanical waves deform the hair cells. sound waves bends hairs

  7. The hair cells are mechanoreceptors that release a chemical neurotransmitter when stimulated.

  8. Sound waves moving through fluid push the filaments; if the filaments bend over enough it causes the hair cells to fire. cell membranes ion channels open

  9. In this way sound waves are transformed into nerve impulses.

Observed symptoms of Otitis media may include the following:otitis-media

  • Severe retraction or perforation of the eardrum (a hole in the eardrum)
  • Scarring or erosion of the small, sound conducting bones of the middle ear
  • Chronic or recurring drainage from the ear
  • Inflammation causing erosion of the bony cover or the facial nerve, balance canals, or cochlea (hearing organ)
  • Erosion of the bony borders of the middle ear or mastoid, resulting in infection spreading to the meninges (the coverings of the brain) or brain
  • Presence of cholesteatoma (a destructive and expanding sac in the middle ear caused by accumulation of dead cells by repeated middle ear infections)
  • Persistence of fluid behind an intact eardrum

Martini, Fredric, H. 2006. Fundamentals of anatomy and physiology. 7th ed. Pearson Education Inc. USA.

Maryland Hearing and Balance Center. 2009.Chronic Otitis Media. retrived March 30, 2009 from http://images.google.ca/imgres?imgurl=http://www.umm.edu/otolaryngology/images/L_cholest.jpg&imgrefurl=http://www.umm.edu/otolaryngology/ear_infections.htm&usg=__Xju8_vmjCabTtFUyoV_lUUrsTlM=&h=366&w=500&sz=38&hl=en&start=10&tbnid=sig3LUsfU-Sc_M:&tbnh=95&tbnw=130&prev=/images%3Fq%3Dotitis%2Bmedia%26gbv%3D2%26hl%3Den%26sa%3DX


Junctional Bradycardia

28/03/2009

Junctional Bradycardia is a condition affecting the heart. Bradycardia is a general term describing any number of electrical-impulses-of-heartphysiological or pathological conditions that cause a slowed heart beat. A typical adult heart beat is around 60-100 beats per minute. A resting heart beat under 60 beats per minute is define as bradycardic. However, symptoms do not generally present until under 50 beats per minute.

There are two bundles of autorhythmic pacemaker cells within the heart. These are the sinoatrial node situated in the upper portion of the right atrium and the atrioventricular node, situated in the junction between the atria and ventricles of the heart. These nodes create the electrical impulses that cause the atria then the ventricles to contract and the heart to beat. The sinoatrial node is the heart’s primary pacemaker. The autorhythmic (self governing) sinoatrial node (SA node) maintains the heart rate at 60-100 beats per minute. Typically electrical impulses are conducted from the sinoatrial nodes then to the atrioventriular node (AV node).

If the sinoatrial node fails to fire, the second pacemaker in the heart, the atrioventricular node will remain to pace the heart’s contrations. The atriventricular node autorhythmically maintains a contraction rate of 40-60 beats per minute. Therefore, junctional bradycardia refers to a slowed pulse (heart rate) that is generated from the AV node due to SA node failure.

Martini, Fredric, H. 2006. Fundamentals of anatomy and physiology. 7th ed. Pearson Education Inc. USA.


Trigeminal neuralgia (tic douloureux)

27/03/2009

Trigeminal neuralgia is a disorder characterized by paroxysmal (short, frequent and gamma_knife_trigeminal_neuralgiarecurring ) facial pain. The trigeminal nerve is the fifth cranial nerve that controls the sensory nerves in the forehead, face, chin and jaw.

Symptoms are typically treated with a pain relieving anticonvulsant drug such as carbamazepine. Surgical treatments may be undertaken for individuals experiencing symptoms that are difficult to manage or those individuals who cannot tolerate the medications.

Surgical treatments for trigeminal neualgia are:

  • neurectomy of trigeminal-nerve branches outside the skull
  • percutaneous ablation (surgical removal of the neural tissue) that creates trigeminal-nerve or trigeminal-ganglion lesions with heat (radiofrequency thermal rhizotomy)
  • injection of glycerol into the trigeminal cistern (retrogasserian glycerol rhizotomy) resulting in chemical ablasion of the neural tissue
  • physical compression (trigeminal-ganglion balloon microcompression

The above procedure all cause trauma to the trigeminal nerve, nerve ganglion or neural root interupting pain signals the faulty nerve was sending to the brain to cause the facial pain.

Barker, Fred, G, Bissonette, David, J, Dong Jho, Hae, Janetta, Peter, J, and Larkins, Mark, V. 1996. The Long term outcome of microvascular decompression surgery for trigeminal neuralgia. The New England Journal of Medicine. 334:1077-1084.

Lunsford, Dade, L and Kondziolka, Douglas. 2005. Pericutaneous retrogasserian glycerol rhizotomy for trigeninalneuralgia: Technique and expectations. Neurological Focus. 18 (1)


Vancomycin Resistant Enterococcus (VRE )

26/03/2009

vreVancomycin Resistant Enterococcus (VRE ) is a strain of enterococcus that has become resistant to the antibiotic Vancomycin. Vancomycin is normally used to treat enterococcal infections. Enterococcus is a bacteria that normally lives in the human bowel. Individuals who are hospitalized, in healthcare facilities, suffering from chronic underlying illness, or those with weakened immune systems are most susceptible to infection by VRE. VRE can be contracted and transmitted through contact with contaminated surfaces such as toilets, grip bars, flushing handles, doorknobs, light switches, bedside tables and telephones.

 

Objects touched by carriers, caregivers, and visitors within a hospital or the home setting or a VRE carrier may become contaminated. Transmission prevention measures include cleaning surfaces with disinfectants such as bleach. However, regular handwashing is the single most effective way to prevent the spread of Vancomycin resistant enterococcus from person to person and a person and their environment.

 

Sante et Service Sociaux Quebec. 2009. Infections Nosocomiales: Entérocoques Résistants à la Vancomycine. Retrived March 26, 2009 from http://www.msss.gouv.qc.ca


Hand washing – primary disease transmission prevention

25/03/2009

 handwashingposter

10 Steps to Successful Handwashing

 

  1. Turn on warm water

  2. Wet hands thoroughly

  3. Squirt soap into palm

  4. Rubbing hands together, lather

  5. Soap palms, backs of hands, between fingers, under fingernails and wrists

  6. Rinse hands removing all soap residue

  7. Take paper towel

  8. Use paper towel to dry hands

  9. Use paper towel to turn off tap

  10. Use paper towel to open restroom door

  missed-areas-of-hands

  • Hand hygiene refers to removing or killing microorganisms (germs) on the hands.
  • Hand hygiene, when performed correctly is the single most effective method of preventing the spread of infection.
  • This practice eliminates transient microorganisms picked up via contact with patients, contaminated equipment, surfaces or the environment.
  • Today we are seeing a re-emergence of bacterial strains and superbugs for which antibiotics are not effective.
  • Hand washing key prevention of pathogen transmission

 

CHICA (2008).The rational for hand hygiene. Community and Hosptial Infection Control Associated Canada. Retrived from http://www.chica.org/links_handhygiene.html.


Methicillin Resistant Staphylococcus aureus (MRSA),

24/03/2009

mrsaMethicillin Resistant Staphylococcus aureus (MRSA), is a variant of the common Staphylococcus aureus bacteria that are normally found in human nares and on skin. In recent years a variant strain has developed to become a human pathogen that carries resistance to the antibiotic Methicillin that was formerly used to treat these infections. Individuals who are hospitalized, in healthcare facilities, suffering from chronic underlying illness, or those with weakened immune systems are most susceptible to infection by MRSA. The spread of Methicillin Resistant Staphylococcus aureus can be prevented by ensuring that all cuts, abrasions, and skin lesions are properly cleaned and covered, by not sharing personal items that come in contact with the skin such as razors and wash cloths and by frequent hand washing.

 

Tracy Unified School District. 2008. Community acquired Methicillin Resistant Staphylococcus aureus (MRSA). Retrieved January 28, 2009 from http://www.tracy.k12.ca.us/MRSA.htm.