LifeSpan 3

Question 1

Whta are the commonly transmitted diseases via respiratory droplet form?

Answer 1

Tuberculosis, legionellosis, measles, rubella, chicken pox, infectious mononucleosis, streptococcal infection, influenza, pertussis, meningococcal meningitis, diphtheria, mumps.

Question 2

Describe tuberculosis (TB)?

Answer 2

TB: droplet nuclei 1-5 micrometers, transmitted via talking, sneezing, coughing, singing, laughing. 1/3 of world population infected. Greatest risk: close contact, immunocompromised, substance abusers, inadequate healthcare, overcrowded living conditions, healthcare workers.

Clinical manifestations: bacteria deposited in alveoli - multiply, rarely transported via lymph or blood, phagocytes (neutrophils/macrophages) engulf bacteria, lymphocytes destroy bacteria and normal tissue causing exudate accumulation then bronchopneumonia 2-10 wks post exposure.

Granuloma occurs - mass of immune cells form wall in attempt to protect body from a microorganism it’s unable to eliminate, then forming mass of fibrous tissue which the center of is called Gohn’s tubercle. Bacteria/macrophages become necrotic, tissue mass calcifies, forms collagenous scar tissue, TB becomes dormant halting disease progression.

If Gohn’s tubercle ulcerated - bacteria again releases from mass causing TB bacilli to again become airborne starting cycle over.

Diagnosis- tuberculin skin test (Mantoux test), purified protein derivative (PPD) of TB bacillus given intradermally evaluating cell-mediated immunity. 48 hrs site evaluated, if inflammation or induration(hardening) present, pt assumed to have TB or past infection, next collect sputum smears, cultures, chest XR to confirm.

Treatment- drug susceptibility testing performed with each pt, 4 drugs used to treat, on drug therapy 9 months.

1. isoniazid (INH)
2. rifampin (RIF)
3. pyrazinamide (PZA)
4. ethambutol (EMB) or streptomycin (SM).

Ongoing testing, sputum cultures obtained - until negative TB present.

Question 3

What are the 4 stages involved in the immune systems response to invasion?

Answer 3

1. Recognition stage.
2. Proliferation stage.
3. Response stage.
4. Effector stage.

Question 4

What are some diseases transmitted via GI tract?

Answer 4

Cholera, hep A, poliomyelitis.

Question 5

What are 5 infectious diarrhea organisms?

Answer 5

1. Escherichia coli.
2. Salmonella.
3. Campylobacter.
4. Shigella.
5. Giardia lamblia.

Question 6

What is bile composed of?

Answer 6

Bile is composed of:

Water, electrolytes, lecithin, fatty acids, cholesterol, bilirubin, bile salts.

Question 7

What is bilirubin and how does it contribute to jaundice?

Answer 7

Bilirubin - pigment derived from hemoglobin breakdown of cells in reticuloendothelial system, including Kupffer cells of the liver.

Bilirubin undergoes a series of processes, becomes conjugated, and is eventually carried to duodenum in the bile.

In small intestine, bilirubin is converted to urobilinogen, which is partly excreted in feces and urine and partly absorbed into portal blood.

In the presence of liver disease, obstruction of bile from gallbladder or excessive breakdown of RBC’s, urobilinogen is absent in urine & feces. Bile and bilirubin are not carried to duodenum and is absorbed by blood causing skin and mucous membranes to be yellow in color, causing itching of skin. Pt’s exhibit dark urine and light colored stools caused by the absent of pigment.

Also, obstruction of bile flow interferes with absorption of fat-soluble vitamins A,D,E,K. Pt’s exhibit vitamin deficiency, including bleeding, which is associated with lack of vitamin K.