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Indwelling catheter associated UTI

Catheter induced UTI

Typical :e.coli,Klebsella pneumonia,staph.saprophticus,proteus.mirabilis(lactose fermenters)(eat protein to be the cool member of the sapron staff club)

Atypical opportunistic:Pseudomonas aeroginasa.(non lactose fermenter)

Summery of UTIs

E.coli and klebsella are leading cause of uti..

staph saprophticus  uti in sexually active women.

Enterococi(strptococcus family ) oppurtunistic uti

U.urealyticu known cause of urithritis but needs special media rich in urea and cholestrol

be patient, good things are coming your way :)

Normal Flora

Blood, Spinal Fluid, Urine: sterile

Cutaneous surfaces (urethra, outer ear included): Staph epidermidis, Staph aureus, Corynobacteria (dyphteroids),Streptocci, Candida spp

Nose: Staph aureus, Staph epidermidis, dyphteroids, assorted streptococci

Gingival crevices: anaerobes = Bacterioides/Prevotella, Fusobacterium, Streotococci, Actinomyces

Oropharynx: Viridans group (alpha hemolytic strep), Neisseria (non pathogenic), H. influenzae (non typeable, meaning, w/o capsule), Candida albicans

Stomach: none

Breast-fed babies colon: microaerophilic/anaerobic = Bifidobacterium, Lactobacillus, streptococci.

Adult Colon: microaerophilic/anaerobic = Bacteroides/Prevotella, E.coli, Bifidobacterium, Eubacterium, Fusobacterium, Gram- anaerobic rods, Lactobacillus, E.faecalis, streptococci

Vagina: Lactobacillus, streptococci, diphteroids, yeasts, Veillonella, Gram- rods

My revised pnemonic for ADP ribosylation A-B toxins

Boring     and      serious      people score high in usmle…

Bordetella pertussis and B.cereus  increases   cAMP by inhibiting Gi

Cool    and     Vibrant   people  also score high…

E. coli  and Vibreo cholerae increases cAMP by  activating Gs

Exception: Please please please remember that  Bacillus anthracis has an edema factor which it self acts as adenylate cyclase…. no ADP ribosylation involved..so hence  cAMP level increases.

[17 Dec 2017] (i thought i’d posted but it’s not appearing? ):) so sorry for the lack of original posts all these months! school has been so tough & i’ve just completed my mid-sem assessments & it’s finally my break! can’t wait to unwind and catch up on my sleep ;-;

Flashcards  with quizlet!

For more: instagram: https://www.instagram.com/studydiaryofamedstudent/

18/1/18 - Recent virology notes! Ignore the headings, I bought some new brush pens and I’m still getting used to them..

Dr Warhol’s Periodic Table of Microbes

56. Ba. Bacillus

There are more than 300 species of Bacillus, which is a whole whopping load of microbes. Just to wrap your head around that number, if you talked about each one for 1 minute you’d be talking nonstop for 5 hours! Take that TedTalks!

Starting with the basics, these organisms found all over the world, predominantly in soil but microbes go where they please, so they have been found in undersea hydrothermal vents as well as in the stratosphere. They are rod-shaped and form spores.

Just to list a few of the most noteworthy and awesome Bacillus species:

Abyssalis: found more than a mile and a half down at the bottom of the South China Sea.

Anthracis: causative agent of Anthrax, the disease, not the band; death, disease, toxins, yahoo!

Azotofixans: fixes nitrogen.

Canaveralius: StarFleet Academy space bacteria living on the walls of the Kennedy Space Center!

Cereus: you get to play with this in General Microbiology, a pathogen causing foodborne illness.

Decolorationis: for you art history majors, isolated from decaying parts of a mural in the Roman necropolis in Carmona, Spain.

Megaterium: it can consume cave paintings.

Stratosphericus: found in high concentrations orbiting the Earth with satellites around 6 miles up!

Subtilis: the grass bacillus; used for industrial enzyme secretion.

Thuringiensis: absolutely famous for producing the BT toxin used as a natural insecticide.

Bacillus cells are Gram positive rods that measures about 1 micron wide by 4 to 10 microns long, but with more than 300 species you will see a range of sizes.

Everyone needs their own Periodic Table of Microbes from https://www.etsy.com/no-en/shop/WarholScience.

Copyright 2016 Warhol.

Antimicrobial Agents - Inhibition of DNA and Protein Synthesis

Bacterial chromosome replication

DNA replication

Bacterial Topoisomerases 

maintain DNA in appropriate state of supercoiling 

cut and reseal DNA

DNA gyrase (topoisomerase II) introduces negative supercoils 

Topoisomerase IV decatenates circular chromosomes 

these are the targets of the quinolone antibacterial agents 

Quinolones

bind to bacterial DNA gyrase and topoisomerase IV after DNA strand breakage 

prevent resealing of DNA 

disrupt DNA replication and repair 

bactericidal (kill bacteria)

Fluoroquinolone is particularly useful against

Gram +ves: Staphylococcus aureus, streptococci 

Gram -ves: Enterobacteriacea; Pseudomonas aeruginosa 

Anaerobes: e.g. Bacteroides fragilis 

many applications e.g. UTIs, prostatitis, gastroenteritis, STIs 

Adverse effects

Relatively well tolerated

GI upset in ~ 5% of patients 

allergic reactions (rash, photosensitivity) in 1 - 2% of patients 

Inhibition of Bacterial Protein Synthesis 

Macrolides 

in 1952: Erythromycin was isolated as the first macrolide (Streptomyces erythreus) 

Newer macrolides: clarithromycin, azithromycin 

Structurally they consist of a lactone ring (14- to 16-membered) + two attached deoxy sugars 

Mode of action 

bind reversibly to bacterial 50S ribosomal subunit 

causes growing peptide chain to dissociate from ribosome → inhibiting protein synthesis 

bacteriostatic (stops reproduction)

Macrolides’ spectrum of activity

good antistaphylococcal and antistreptococcal activity 

treatment of respiratory & soft tissue infections and sensitive intracellular pathogens • e.g. Chlamydia, Legionella 

Adverse effects

Generally well tolerated

nausea 

vomiting 

diarrhoea 

rash 

Aminoglycosides

large family of antibiotics produced by various species of Streptomyces (“mycin”) and Micromonospora (“micin”) 

include: streptomycin, neomycin, kanamycin, gentamicins, tobramycin 

Structure = linked ring system composed of aminosugars and an aminosubstituted cyclic polyalcohol 

Mode of action of aminoglycosides

Bind irreversibly to 30S ribosomal subunit 

disrupt elongation of nascent peptide chain 

translational inaccuracy → defective proteins 

bactericidal 

Spectrum of activity 

broad spectrum; mainly aerobic G-ve bacilli (e.g. P. aeruginosa) 

used to treat serious nosocomial infections (hospital acquired infections)

First TB antibiotic

Used for cystic fibrosis 

Adverse effects

all aminoglycosides have low Therapeutic Index (only a small amount needed to become toxic)

renal damage, ototoxicity, loss of balance, nausea