Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
38 Cards in this Set
- Front
- Back
- 3rd side (hint)
|
Gram-Positive Cocci
Semisynthetic penicillinase resistant penicillins "beta-Iactamase-resistant penicillins" |
oxacillin,
cloxacillin, dicloxacillin, nafcillin |
Methicillin belongs to this group
"methicillin sensitive" or "methicillin-resistant Staphylococcus aureus" (MRSA) |
|
|
Penicillin G, penicillin VK,
|
These agents are effective against
streptococci, such as S. pyogenes, viridans group streptococci, and s. pneumonia, |
but not against staphylococci.
|
|
|
Ampicillin
|
This is effective against streptococci, such as S. pyogenes, viridans group streptococci,
and s. pneumonia, but not against staphylococci. also has some activity against E. coli. Both are effective against enterococci and Listeria can be useful against Gram-negative bacteria, such as Neissera. |
Ampicillin is only effective
against staph when ampicillin is combined with the beta-Iactamase inhibitor sulbactam |
|
|
Amoxicillin
|
This is effective against streptococci, such as S. pyogenes, viridans group streptococci,
and s. pneumonia, but not against staphylococci. also has some activity against E. coli. Both are effective against enterococci and Listeria can be useful against Gram-negative bacteria, such as Neissera. |
Gram-Negative bacteria covered by Amoxicillin
( HELPS) H.influenza E. coli L. isteria S. almonela |
|
|
first-generation Cephalosporins
|
cefazolin,
cefadroxil, cephalexin; |
will all cover the same range of organisms that
the semisynthetic penicillins will cover. In addition to staphylococci and streptococci, first- generation cephalosporins will also cover some Gram-negative organisms. First-eneration agents will only reliably cover Moraxella, and E. coli. In the case of Gram-positive infection, you should generally answer the use of a first-generation agent. |
|
|
secondgeneration Cephalosporins:
|
cefoxitin,
cefotetan, cefuroxime, cefprozil, loracarbef |
second-generation cephalosporins:
Will all cover the same range of organisms that the semisynthetic penicillins will cover. In addition to staphylococci and streptococci, second-generation cephalosporins will also cover some Gram-negative organisms. Second-generation agents will cover everything a first-generation cephalosporin covers, as well as a few more Gram-negative bacilli such as: - Providencia, - Haemophilus, -Klebsiella, - Citrobacter, - Morganella, - Proteus. |
|
|
Macrolides
|
erythromycin,
clarithromycin, azithrornycin |
These agents are alternatives to penicillins and cephalosporins for Gram-positive infection.
Macrolides should not be used for serious staph infections. The |
|
|
Third Generation Cephalosporins
|
Cefriaxone
Cefotaxime Ceftazidime |
Cefriaxone: First line for Penomococcus including partially insensitive organism
- Meningitis - Community acquired pneumonia( in combination with Macrolides) - Gonorrhea - Lyme involving Heart or brain |
|
|
Fourth Generation Cephalosporins
|
Cefepime
|
Cefepime has better Staphylococcal coverage compared with the third generation it is use to treat:
- Neutropenia and fever - Ventilator- associated pneumonia |
|
|
Adverse Effects of Cephalosporins
|
Cefoxitin and Cefotetan deplete Prothombin and increase risk of bleeding
with Ceftriaxone there is inadequatebilliary metabolism |
|
|
|
Carbapenams
|
Imipenam
Mepropenem Ertapenem Doripenem |
They cover Gram negative bacilli
including many that are resistant Anaeerobes, Streptococci Staphylacocci They are use to treat Netropenia and fever Ettrapenam does not cover Pseudomonas |
|
|
Monobactam
|
Aztreonam
|
Exclusively for Gram Negative Bacilli including Pseudomonas
No Cross reaction with Penecillin |
|
|
Fluoroquinolones
|
Ciprofloxacin
Gemifloxacin Levofloxacin Moxifloxacin |
- The best therapy for community acquired pneumonia including penecillin-resistant pneumococcus
- Gram-Negative Bacilli including most pseudomonads - Ciprofloxacin for cystitis and pyelonephritis. - Moxifloxacin will not enter the urine in high enough concentration to treat cystitis - Moxifloxacin can be use as single agent for Diverticulitis and does not need Metronidazole. - Ciprofloxacin, Gemifloxacin, Levofloxacin most be combined with Metronidazole because they do't cover anaerobes in Diverticulitis and GI infections. !!Quinolones Cause: 1- Bone growth abnormalities in children and pregnant women 2- Tendonitis and Achilles tendon rupture 3- Gemifloxacin removed because of Glucose abnormalities |
|
|
Aminoglycosides
|
Gentamicin
Tobramycin Amikacin |
- Gram-negative bacilli (bowel- urine -bacteremia)
- Synergistic with Beta-Lactam antibiotics for Enterococci and Staphylococci !! - No effects against anaerobes, since they need oxygen to work - Nephrotoxic - Ototoxic |
|
|
Doxycycline
|
- Chlamydia
- Lyme disease limited to rash, joint, or seventh cranial nerve palsy - Rickettsia - Primary and secondary Syphilis in those allergic to Penicillin - Borrelia, Ehrlichia, and Mycoplasma |
Adverse Effects:
- Tooth discoloration (children) - Fanconi Syndrome ( Type II RTA proxsimal) - Photosensitivity - Esophagitis / Ulcer |
|
|
Trimethoprim/Sulfamethoxazole
|
- Cystitis
- Pneumocystis Pneumonia treatment and prophylaxis - MRSA of skin and soft tissue (cellulitis) |
- Rash
- Hemolysis with G6Pd deficiancy - Bone marrow suppression because it is Folate antagonist. |
|
|
Beta-Lactam/ Beta-Lactamase combination
|
- Amoxicillin / Clavulanate
- Ticarcillin / Clavulanate - Ampicillin/ Sulbactam - Piperacillin/ Tazobactam |
Beta-Lactamase adds coverage against sensitive Staphylococci to these agents
|
|
|
Gram-Positive Cocci
|
Staphylococci
Streptococci |
The best initial therapy for Gram-Positive organism are:
- Oxacillin, Cloxacillin, Dicloxacillin, Nafcillin - First Generation Cephalosporins: - Cefazolin, Cefadroxil, Cephalexin - Fluoroquinolones - Ciprofloxacin, Gemifloxacin, Levofloxacin, Moxifloxacin - Macrolides - Erythromycin, Clarithromycin, Azithrornycin |
|
|
Oxacillin ( Methicillin) - Resistant Staphylococcus are best treated with :
|
- Vancomycin
- Linezolid - Daptomycin - Tigecyclin |
- Linezolid Adverse effects : Reversible bone marrow toxicity
- Daptomycin Adverse effects : Elevated CPK |
|
|
Minor MRSA infection of the skin are treated with :
|
- TMP/SMX
- Clindamycin - Doxicyline |
|
|
|
Anaerobes
|
- Oral ( Above Diaphragm): Penicillin G, penicillin VK,
Clindamycin - Abdominal/ Gastrointestinal: Metronidazol - Pipracillin - Carbapenems - second-generation Cephalosporins |
|
|
|
Gram- Negative Bacilli
( E.coli - Klebsiella, Proteus, Pseudomonas, Enterobacter, Citrobacter ) |
- Fluoroquinolones
- Aminoglycosides - Carbapenems - Pipracillin - Ticracillin - Aztreonam Cephalosporins |
|
|
|
Carbapenems
|
- Imipenem,
- Meropenem, - Ertapenem |
Fully active against Enterobacteriaceae and Pseudomonas,
They are similar in Gram-negative coverage to the aminoglycosides and third-generation cephalosporins. In addition, they have excellent staph and naerobic coverage. Although effective in polymicrobial infections, they are best used in Gram-negative infections. All carbapenems are equally effective against anaerobes, as compared to metronidazole. Ertapenem will not cover Pseudomonas. |
|
|
Meningitis
|
An infection or inflammation of the meninges, which is the connective tissue covering the central
nervous system. Regardless of microbiologic etiology, all forms of meningitis present with fever, photophobia, headache, nuchal rigidity (neck stiffness, positive Kernig and Brudzinski signs), as well as nausea and vomiting. CT scan of the head is the best initial diagnostic test if the patient has papilledema, focal motor deficits, new onset seizures, or severe abnormalities in mental status, or is immunocompromised (HIV infection, immunosuppressive medications, post-transplantation, � If none of the above is present, a lumbar puncture can be safely done without doing a CT scan of the head first, which can significantly delay the diagnosis. � If the lumbar puncture is delayed more than 20-30 minutes for any reason, then the best initial step is to give an empiric dose of antibiotics. ��The most accurate test for bacterial meningitis on the lumbar puncture is the culture of the CSF.�� |
- Streptococcus pneumoniae (60%)is the most common cause of meningitis for all patients
- Group B Streptococci (14%) - Haemophilus Influenza (7%) - Neisseria Meningitidis (15%) - Listeria Monocytogenes (2%) - Staphylococcus aureus with recent neurological surgery - Cryptococcus is more common in those who are HIV positive and who have profound decreases in their T-cell counts - Rocky mountain spotted fever (RMSF) is common in those Camper- hiker , Rash moves from arms/ legs to trunk, tick remember in 60% - Lyme disease can also cause meningitis and is more common in those Camper- hiker , Rash shaped like a target, Joint Pain, Facial Palsy, tick remember in 20% - TB --> Pulmonary TB in 85% - Viral - Neisseria --> Adolescent, Petechial rash |
|
|
CSF in Bacterial Meningitis
|
Cell Count:
� 1000s, Neutrophils Protein level : � Elevated Glucose Level � Decreased Stain � 50-70% culture : � 90% |
|
|
|
CSF in :
Cryptocccos, Lyme , RIckettsa |
Cell Count:
� 10s, 100s Lymphocyte Protein level : � possibly Elevated Glucose Level � possibly Decreased Stain � Negative culture : � Negative |
|
|
|
CSF in :
Tuberculosis |
Cell Count:
� 10s, 100s Lymphocyte Protein level : � Markedly Elevated Glucose Level � Maybe low Stain � Negative culture : � Negative |
|
|
|
CSF in :
Viral |
Cell Count:
� 10s, 100s Lymphocyte Protein level : � Usually Normal Glucose Level � Usually Normal Stain � Negative culture : � Negative |
|
|
|
Head Ct is necessary prior to LP only if:
|
1- Space occupying lesion may cause herniation
2- Papilledema 3- sizures 4- Focal neurological abnormalities 5- Confusion interfering with neurological examination |
if there is a contraindication to immediate LP
� Giving antibiotics is the best initial step in managment |
|
|
The best initial treatment for bacterial meningitis is:
|
A third-generation Sephalosporin, such as:
Ceftriaxone plus vancomycin and Steroid |
Listeria is resistant to all forms of cephalosporins
you must add Ampicillin for those who have risk factor for Listeria � Add Ampicillin for : - Elderly - pregnancy - Immunocompromised |
|
|
Risk factors for Listeria
|
1- Elderly
2- Neonate 3- Steroid Use 4- AIDS or HIV 5- Immunocompromised 6- Alcoholism 7- Pregnancy |
|
|
|
The most common neurological complication of meningitis is:
|
Hearing loss
|
Eight cranial nerve deficit or Deafness
|
|
|
Summery of bacterial meningitis:
|
- Streptococcus pneumoniae (60%)
- Group B Streptococci (14%) - Haemophilus Influenza (7%) - Neisseria Meningitidis (15%) - Listeria Monocytogenes (2%) |
- Streptococcus pneumoniae: Reservoir unknown , trauma, CSF leak
- Neisseria Meningitidis: Young, healthy, military, College Students - Haemophilus Influenza : Rare since introduction of group B Vaccine - Listeria Monocytogene: Immunocompromised - Staphylococcus aureus: Nerulosurgey, Penetrating trauma, skin damage |
|
|
Neisseria Meningitidis : additional managements:
|
- Respiratory isolation
- Rifampin or Ciprofloxacin to the close contact to decrease nasopharyngeal carriage �Close contact means those who have major respiratory contact , such as: - Household contact, - Kissing, - Sharing Cigarettes - eating utensils. |
Routine school and work contact are not close contact
� Healthcare workers qualifies only if they : - Intubate - Suctioning - Have contact with respiratory secretion |
|
|
Cryptococcal Meningitis
|
1- HIV/ AIDS is the most common risk factor , there is no specific CSF finding
2- Indian Ink or Cryptococcal antigen are diagnostic test �� Greatest Predictor of mortality: �� a) Low CSF cell count (< 20 HPF) b) High opening pressure of CSF (>250 mm H2O) c) High antigen titer ( >1:1024) |
1- it is slower in onset
2- Does not usually have fever, Headache, Stiff neck, and photophobia 3- may have Normal CSF WBC Count � the best initial therapy is Amphotericin and Flucytosine ( Adding Flucytosine to Amphotericin sterilized CSF faster) - after several weeks followed by Fluconazole ��if CD4 stays low then life long Fluconazole �� |
|
|
Tuberculous Meningitis
|
1- Lung Lesion
2- A recent immigrant 3- Extremely high CSF protein level ��Treatment �� Same as Pulmonary TB except: 1- Add Dexametazone to decrease neurologic complication 2- Extend the length of treatment |
the most accurate test is :
1- Tale high volume CSF sample for culture 2- Centrifuge the samples |
|
|
Rocky Mountain Spotted Fever
|
RMSF is cause by Rickettsia rickettsii
1- Petechial rash moving from the wrists and ankles inwards towards the body ( Centripetal pattern ) 2- Camping or hiking 3- Many non specific symptoms such as Artheralgia, Myalgia, Headache, and Fevar |
Dx. With:
1- Serologic test in 95% 2- Fluorescent antibody test , takes 2-3 weeks 3- Skin Biopsy is difficult , but can give definitive Diagnosis �� Doxycycline is the best initial therapy �� |
|
|
Lyme
|
Nothing specific on CSF in term of cell count, stain, or protein level
1- History of hiking/ camping 2- previous"target-shaped" rash 3- Joint pain, AV block, or facial Palsy |
��the most accurate test is ELISA or Western blot of CSF��
��Treatment �� 1- Intravenous Ceftriaxone, Cefotaxime, or Penicillin |
