Microbe-Human Interactions; Specimen Collection

Transient

microbes that occupy the body for only short periods

• always changing

Residents

microbes that become established (we always have them)

10:1

microbes:human cells ratio

normal flora/microbiota

the microbes that are normally associated with humans are …

bacteremia

the presence of bacteria in blood 

• result from ordinary activities 

• dental or medical procedures 

• infections 

septicemia

bacteria in the blood, actively growing and often occurs with severe infection 

• leads to sepsis 

sepsis

an overwhelming immune response due to a bacterial infection

• chemicals released into blood to fight the infection trigger widespread inflammation → leads to blood clots and leaky blood vessels 

infancy

When is your microbiome introduced?

Staphlococcus

Flora of the skin- bacteria

Candida

Flora of the skin- fungus

upper dead layers of epidermis and glands

Where do microbes live on the skin?

Streptococcus

Flora of respiratory tract- bacteria 

Candida

Flora of respiratory tract- fungus 

anaerobic

environment of the oral cavity

mucociliary elevator

pushes mucus up

• microorgs try to enter the lower respiratory tract are expelled by the activity of cilia and mucous

colon

What part of the digestive system has the largest number of bacteria 

Bacteroides, Lactobacillus

flora of the digestive system- bacteria

Candida

flora of the digestive system- fungus

vagina and outer opening of urethra

female sites that harbor flora in the urogenital tract

anterior urethra

male sites that harbor flora in the urogenital tract

Lactobacillus, Staphylococcus

flora of the urogenital tract- bacteria

Candida

flora of the urogenital tract- fungus

too much or wrong location

How can your normal flora make you sick?

pathogens

microorganisms that cause disease

virulence

the degree a pathogen can cause disease 

infection

where a microorganism gains entrance into a host and replicates 

disease

deviation from the normal state structure or function of an organism 

pathogenesis

the mechanism pathogens take to establish disease

sign

something you can detect without speaking to a patient

symptom

something only the patient can tell you, you can’t know just by looking at them 

culturing from the throat

swab off to the side to prevent gag reflex 

culturing from the outer ear

• use moistened swab to remove any debris/crust from ear canal 

• obtain a sample by firmly rotating swab in outer canal 

culturing from the inner ear

• clean ear canal with soap solution and collect fluid via syringe aspiration technique (myringotomy) 

• can insert tube to allow for drainage to continue (tympanostomy)

otis media

biofilm infection in inner ear

wound culturing 

• only infected part is sampled and not any other part of skin 

• swab, biopsy, aspirate 

conjunctivitis (pink eye)

the inflammation of the conjunctiva of the eye and can be caused by either viruses or bacteria 

viral infection

no crust, clear discharge (conjunctivitis signs)

bacterial infection

crusty eye, discharge (not clear) (conjunctivitis signs)

sputum

a mixture of saliva and mucus coughed up from the respiratory tract

• want sample of mucus not saliva

nasal and bronchial sampling

1. sputum 

2. nasophyrangeal washes 

3. nasal swab

4. bronchial lavage 

bronchial lavage wash

performed by flushing a saline solution into the lungs and collecting the wash sample for laboratory analysis for the presence of pathogens

• inject sterile saline → suck it back up 

urine collection

1. first urination of the day 

2. clean catch (can’t go into toilet bowl) 

3. collect mid-stream 

urogenital tract sampling

• STDs: penile, endocervical and vaginal culturing 

• sterile swab or brush inserted into the urethra of penis or cervix to scrape off cells or specimen of vagina

intestinal and stool sampling

colonoscopy

colitis

refers to inflammation of the inner lining of the colon (large intestines)

• caused by Clostridium difficilf (cidiff)

Cerebral spinal fluid

insert needle with cerebrospinal fluid in lumbar verebrae 

phlebotomy

the practice of drawing blood from patients and taking the blood specimens to the lab to prepare for testing 

venipuncture

collect from superficial vein 

• use vein bc blood pressure is low

capillary blood

finger, earlobe, big toe (infants), heel

arterial puncture

radial artery or brachial artery (dangerous due to high blood pressure) 

• good for checking gas exchange at the lungs