Acquired resistance

Occurs when pathogen acquires gene for bacterial resistance through maturation
over prescription of antibiotics- if there's no bacterial illness
failed to complete full course
long-term prophylactic use appropriate for children of sickle-cell disease (pcn throughout childhood to decrease the life-threatening systemic infection)

Beta lactamase

A bacteria secreted enzyme that splits the beta lactam ring

Pathogens

Microbes capable of causing disease

Antibiotics

Natural substance produced by bacteria that kills other bacteria
bacteriostatic agents: slows the growth of bacteria
bacteriocidel agents: kills bacteria

The selection of antibiotic

Use of C&S testing- (urine, blood, sputum, wound, drainage )
collect the specimen before starting antibiotic. Bacteria take several days in viruses take several weeks
broad-spectrum/ serious immediate release for wide variety of bacteria. 
narrow spectrum/ effective for narrow group of bacteria

Super infections

Secondary infection when too many holes for are killed by antibiotics
EX: yeast infection (thrust, fragile infection) c diff
signs/sx: diarrhea, bladder pain, people urination, abnormal national discharge

Host factors influence of antibiotics

Immune system status
local condition an infection site
allergic reactions
age
pregnancy
genetics

Classes of antibiotics- time-dependent drugs

Penicillins
cephalosporins
macrolides
aminoglycosides
fluoroquinolones
sulfonamides

Most effective on gram-positive bacteria used for wide variety of infections and for prophylaxis prior to invasive procedures with heart valve disease and children with sickle-cell to prevent systemic infections

pcn G (K+)
nafcillin (pcnase restistant)
amoxicillin (broad spectrum)
piperacillin (extended Septrum)

Class: PCN- safest class of antibiotics
action: anti-bacterial with cell wall inhibitor
admin: watch for reaction for 30 min after parenteral admin, do not mix with aminoglycosides in the same IV solution, give IV meds 1 hr apart, Preg Cat B.
Side: diarrhea, N&V, pain and injection site, super infections, anaphylaxis late hypersensitivity
Con: excreted through kidneys use caution with severe renal disease

PCN

Inter: oral contraceptives decreased effectiveness, Colestipol decreased absorption of PCN, potassium sparing diuretics- hyperkalemia, do not give with aminoglycoside ATB. naficillin works against beta-lactamase (penetrates) restistaint
Labs: positive Coombs test and falls positive urinary or serum proteins

Cephalosporins

Binds to bacterial cell wall and inhibits cell wall synthesis
act with broad-spectrum activity against gram-negative organisms
used for: serious infections of lower respiratory tract, central nervous system, genitourinary system, bones, blood, joints

Possible cross reaction with PCN allergies

cefazolin/ Ancef 1st gen

cefaclor/ Ceclor 2nd gen

cefdinir/ Omnicef 3rd gen

cefepime/ Maxipime 4th gen

Class: cephalosporins
action: antibacterial- bacteriocidal that asked to PCN binding protein to inhibit bacterial cell wall synthesis
admin: IM inj. into deep lg. Muscle to prevent injury to tissues. Preg Cat B
side: rash, diarrhea, superinfection's with prolonged., Severe hypersensitivity reaction, pain & phlebitis at IM site, seizures

Cephalosporins

Con: hypersensitivity, use caution with severe renal disease
Inter: cefazolin with nephrotoxic drugs increase nephrotoxicity, may have synergistic antimicrobial action with other antibiotics, anticoagulants effects may be increase.
Labs: false positive your glucose or positive Coombs test.

Macrolides

Inhibits protein synthesis by binding to the bacterial is
effective against most gram-positive and many gram-negative bacteria
use for: whooping cough, legionaries disease, infection by Streptococcus, H. Influenza and mycoplasma pneumoniae
low dose listed as bacteriostatic
high dose listed as bacteriocidal

azithromycin/ (Zithromax)
erythromycin/ (E-Mycin)

Class: macrolides
action: antibacerial- inactivated by stomach acid for penicillin resistant infections by a protein synthesis inhibitor.
Admin: give oral on empty stomach and glass of H2O, shake bottle thoroughly, do not give immediately before or after fruit juices, preg Cat B.
side: N&V, AB cramping, hearing loss, vertigo, dizziness in high doses with impaired hepatic or renal excretion, cardio toxic, fatal dysrhythmias

Macrolides

Con: hypersensitivity to macrolides, terfenadine, astemizole, cisapride
Inter: anesthetics, azo antifungals, anticonvulsants- erythromycin toxicity, cyclosporine risk of nephrotoxicity, increase the effects of warfarin, do not use with statins- increase of muscle toxicity, Ethan all decreased absorption
Labs: interfere with AST & false urinary catecholamine values.
herbal/food: St. John's wort decreased effectiveness

Aminoglycosides

Inhibits bacterial protein synthesis
used for: the treatment of serious systemic infections caused by aerobic gram-negative bacteria, mycobacteria, some protozoans

gentamicin/ (Garamycin)

amikacin

tobramycin

Class: aminoglycosides
action: antibacterial- inhibiting bacterial protein synthesis
admin: IM admin deep lg muscle, only IM and Ivy drug solutions that are clear, colorless, slightly yellow, discard if this colored or have particulate matter, withhold drug if serum level is above 5 -10 MCG/ML, Preg Cat C
side: rash, N&V, fatigue, resistance to gentamicin, cross resistance among aminoglycosides, neurotoxicity, ototoxicity (loss of hearing/balance) tendinitis, vertical, headaches, muscle twitching, seizures, paresthesias

Aminoglycoside

Black Box: Neuromuscular blockage, respiratory paralysis, nephrotoxicity with pre-existing kidney disease, reduced kidney function, protein urea, elevated BUN and creatinine levels.
Con: hypersensitivity aminoglycosides, monitor with impaired renal function or pre-existing hearing loss.
Inter: amp B, Lasix, ASA- increase ototoxicity risk, amp B or vancomycin increase risk of nephrotoxicity
labs: increase serum bilirubin, creatinine, lactate dehydrogenase (LDH), BUN, AST, ALT, cerium calcium, sodium, potassium

fluoroquinolones

Bacteriocidal, bio warfare agents
inhibits bacterial DNA synthesis by inhibiting DNA gyrase & topoisomerase IV
used for: respiratory infections, G.I., genitourinary tract infections, skin and soft tissue infections, UTIs, prophylaxis of anthrax infection

ciproflaxin/ (Cipro) 2nd gen

levoflaxin 3rd gen

moxiflaxcin 4th gen

Class: fluoroquinolones
action: anti-bacterial due to DNA synthesis inhibitor
Admin: give 4 hr before antacids or ferrous sulfate. No under 18, preg, or lactation. Preg Cat C.
Side: N&V, diarrhea, headaches, dizziness, tendinitis, sleep disturbances, dysrhythmias, hepatotoxicity, ruptures of Achilles tendon, muscle weakness with myasthenia Gravis, risks for pt over 60, kidney heart and lung transplant recipients, concurrent corticosteroid therapy

fluoroquinolones

Con: hypersensitivity, discontinued if pain or inflammation of a tendon
inter: warfarin increase anticoagulant effect and result in bleeding, increase theophylline levels, and assets and minerals decreased absorption
Labs: increase values of ALT AST serum creatinine in BUN
herbal/food: increase serum levels of caffeine- nervousness, anxiety, party. Dairy products or calcium fortified drinks decreased absorption

Suppress bacterial growth by inhibiting bacterial synthesis of folic acid
use for: urinary tract infections's, pnuemocystis carnii pneumonia, shigella infections of small bowel

trimethoprim-sulfamethoxazole/ (Bactrim)

Class: sulfonamides- combination drug
action: antibacterial which inhibits the bacterial metabolism of folic acid. A synergistic action with the combination drugs
admin: give oral with full glass of H2O, Preg Cat C

Sulfonamides

side: N&V, skin rash, itching, fever, crystalluria, oliguria, renal failure, agranulocytosis, thrombocytopenia, photosensitivity, SJS/Stephen Johnson syndrome (scan sloughing and mucous membrane), blood dyscaria, decrease bone marrow,

Con: hypersensitivity sulfonamides, megablastic anemia due to folate deficiency, kernicterus in pregnant/lactating mothers, decreases potassium excretion caution with hyperkalemia pt.

Sulfonamides

Inter: enhance the effects of certain anticoagulants resulting in serious or life-threatening interactions, increase methotrexate toxicity, decreasing hepatic metabolism may cause phenytoin toxicity, spironolactone (diuretics) – hyperkalemia

Herbal/food: potassium supplement should not be taken during therapy
tx of overdose: renal elimination increase by acidification of the urine

Anti-infective/anti-protozoan

Anti-infective against anaerobes that are common causes of abscesses gangrene diabetic skin ulcers and the one infections
dual activity against both bacteria and multicellular parasites

metronidazole/ (Flagyl)

Class: anti-effective and anti-protozoan
action: treatment of non-malarial protozoan
admin: extended release swallow whole on an empty stomach, contradicted during first trimester of pregnancy, Preg Cat C.
Side: anorexia, nausea, diarrhea, dizziness, headache, dry mouth, metallic taste, bone marrow suppression

Anti-infective/anti-protozoan

Blackbox: oral in injection is carcinogenic in laboratory animals should be used only for approved indications.
Con: pt with trigger monist during first trimester of pregnancy, hypersensitivity to the drug, blood dyscarias due to bone marrow suppression
Inter: oral anti-coagulant's hypoprothrombinemia, alcohol may elicit dusulfiram reaction, lithium may elevate lithium levels
Labs: decrease values for AST and ALT

Anti-tubercular

Caused by Mycobacterium tuberculosis
cell wall resistance to anti-infectives
body's immune response attempt to isolate pathogen by walling it off
tuberculosis made remain dormant in walled off areas called tubercles
decreased immune system can give tuberculosis opportunity to become effective

Length of therapy for tuberculosis

6 to 12 months average of 9 months
needed to reach isolated pathogens tubercles
therapy must be continued even if no symptoms
patients with multi-drug-resistant infections require therapy for 24 months

Multi-drugs are needed because the complex microbes are slow-growing and commonly developed drug resistance

Chemoprophylaxis for TB

Antituberculosis drugs are used to prevent disease in high risk populations
close contact with family members of recently infected TB patients
patients with AIDS
patients who are receiving HIV-positive or are receiving immunosuppressant drugs

isoniazide/ (INH)

Class: anti-tubercular
action: anti-tuberculosis by inhibiting the synthesis of mycolic acids which are the components of micro bacterial cell walls.
Admin: give one empty stomach, 1 hr after or 2 hr prior meals, IM - deep muscle and rotate sites, Preg Cat C.
Side: numbness of hand and feet, rash, fever, neurotoxicity convulsions, optic neuritis, dizziness, coma, memory loss, psychoses, paresthenia of feet and hands.

antituberculosis

Blackbox: hepatotoxicity, jaundice, fatigue, elevated hepatic enzymes, loss of appetite, daily alcohol consumption
Con: hypersensitivity to drug and pt severe hepatic impairment.
Inter: antacids  decrease absorption of INH, disulfiram-lack of coordination and psychotic reactions, alcohol increased risk of hepatotoxicity, INH may increase serum levels of phenytoin and carbamazepine

antitubercular

Labs: may increase values of AST and ALT
herbal/food: food interferes with the absorption, foods containing tyramine increase INH toxicity
tx for overdose: Pyridoxine (vit B6) may be infused in a equal does to that of INH overdose to prevent seizures and correct metabolic acidosis. May repeat several times until consciousness is regained

Assessments throughout administration

Decrease signs/ sx of infection,
fever below 100.4,
lab levels WNL
no adverse effects – super infections, allergic responses, toxicities specific to each class

relevant labs for infection

decreased red and/or white blood cells

decreased platelet count

increases renal/ hepatic levels

sx to report stat to dr for antibacterial medications

severe diarrhea w/ mucus, bld, or pus

yellowiwng of sclera or skin

decreased urine output           urticaria

darkened urine          throat tightness

febrile seizures          difficulty breathing

change in behaviors            veritgo           wheezing

loss of consciousness (LOC)

itching            rash           flushing             syncope

swelling      walking issues

pain in heel, lower leg, or calf

proper self-admin teaching for anti-bacterials

complete therapy              wear sunscreen

no antidiarrheals               do not share

hand hygeine                    labs as directed

take w/ food or milk if GI          discard outdated meds

add'l contraceptive measurements    no alcohol

evenly spaced doses

check for allergic reaction, superinfections, temp decreased w/in 3 days

increase fluids 2/3 liters and dairy products daily

how can hurses help limit resistant bacteria

prevent infections

encourage pt to complete therapy dose

order only if necessary

dietary teaching for IHN (TB)

increase VitB6

no food with tyramine

no alcohol or acidic beverages

take on an empty stomach

full glass of H2O

lifespan for antibacterials

children- renal toxicity

child bearing- add'l bc (decreased effect from ATB

older- renal toxicity, increased risk for falls, metabolism/excretion decreased