Table of contents
Quick Reference Guide
| Cellulitis | Staph + Strep | 1st line: Cephalexin 500mg PO qid x7d 2nd line: cloxacillin 500mg PO q6h x10-14d or clindamycin 300mg PO q6-8h x10-14d, total <1.8 g/d In General: Cephalexin (Keflex) or Cefazolin (Ancef) - Ciprofloxacin + clindamycin - Amoxacillin + Clavulin (Big guns, if diabetes b/c atypicals, broad range) |
| Pneumonia | B-lactam Susceptible
B-lactam non-susceptible
| - New macrolide - If healthy, young, macrolide monotherapy (if low PORT) - Azithromycin (atypicals) + ceftriaxone (S. pneumo + H. influ) - Resp fluoroquinolone (moxiflox or Levoflox) broader range (if high PORT) |
| UTI | E.coli (-) Staph Sapro (+) Klebsiella (-) Enterococcus (+) Proteus (-) Pseudomonas (-) | - TMP+TMZ (25% E.coli resistance) - Ciproflox (covers pseudomonas 25%res, maybe poor against enterococcus?) - Nitrofurantoin (only cystitis, not pyelo, bad) For enterococcus - Amoxacillin (covers enterococcus, maybe poor against pseudomonas?) - Vanco, Ampicillin IV |
| Meningitis | N. meningitimus Strep pneumo H. influ Listeria | - Pip-tazo (o.k CSF penetration, not great) - Vancomycin (strep pneumo)+ ceftriaxone (all else) o Add ampicillin for Listeria if elderly, alcohol, homeless) |
| Intra-abdo | Bacteroides fragilis (anae) E.coli (aerobe) | - Metronidazole + ceftriaxone (or cipro) - Single agent: pip-tazo, meropenem/ertapenem, moxifloxacin |
| SSI prophylaxis |
| - Biliary tract: cefazolin - Stomach/duodenum: cefazolin - Small bowel: cefazolin - Colin: cefazolin + metronidazole - Appendectomy: cefazolin + metronidazole (Give 30min pre-op, give another dose if surg >4hrs) |
| C.diff colitis | Clostridium difficile | - Severe diarrhea, elevated WBC, 2nd to ABX administration - Tx: oral flagyl or vancomycin |
| Necrotizing fasciitis | Type I: B-hemolytic Strep Type II: Polymicrobial | - Consider penicillin 4 million IU IV q4h - Consider: clindamycin 900mg IV q6h (GP, and anaerobes) |
| Strep Pharyngitis | Group A beta-hemolytic Strep | Pediatric PEN V 25-50 mg/kg/d PO div q6h x 10d amox/clav 45 mg/kg/d PO div. q12h x10d clarithromycin 15 mg/kg/d PO div. bid x10d azithromycin 12 mg/kg/d PO x5d Adults pen V 500mg PO bid or 250mg qid x10d cefuroxime 250mg PO bid x4d clarithromycin 250mg PO bid x10d azithromycin 500mg PO once, then 250mg daily x4d If Penicillin allergy give erythromycin |
| Sinusitis | S. pneumoniae H. influenzae M. catarrhalis Group A Strep Anaerobes S. aureus | 1st line: amoxicillin 1g PO tid x10d (if penicillin allergey: TMP/SMX DS 1tab PO bid) 2nd line: amox/clavulin 200/125mg PO bid x10d 3rd line: clarithromycin XL 1000mg PO OD x10d |
| Acute Otitis Media | Viral S. pneumoniae H. influenzae M. catarrhalis | <10y.o.: 1st line: amoxicillin 75-90 mg/kg/d PO tid x5d 2nd line: amoxicillin/clavulin 3rd line: macrolides >10yo amoxicillin 500mg PO tid x7-10d Penicillin allergy: cefuroxime, azithromycin, clarithromycin |
| Spinal Infection epidural abscess etc.. | 3rd gen cephalosporin +/- ampicillin +/- vancomycin | |
| Gonorrhea |
|
| Bacteria` | Mgmt |
| MRSA | Cloxacillin + TMX |
URTI
- Viral Causes
- Parainfluenza
- Adenovirus
- RSV
- Rhinovirus
- Enterovirus
- Bacterial causes:
- Strep pyogenes (Group A strep)
Pulmonary Infections
- Common organisms:
Streptococcus pneumoniae- Haemophilus influenzae
- Mycoplasma
- Chlamydia pneumoniae
- Other pathogens:
- Staph aureus
- often ventilator associated pn.
- Gram negatives
- uncommon, unless lung disease or alcoholism. (reduced gag reflex). Usually hospitals and nursing homes.
- Legionella
- vary with seasons and geography.
- Anaerobes
- often aspiration pneumonias.
- Viral
- influenza, parainfluenza, respiratory syncitial virus (RSV).
- Staph aureus
- Risk Factors:
- Viral infections (damage cilia)
- Smoking (damange bronchial cells)
- Alcohol (depresses coughing and epiglottis)
- Elderly (decrease dhumoral and cell mediated immunity)
- Immunosuppressed
- Chronic diseases
- Cold weather (dries up mucous)
- Classified as:
- Typical Pneumonia
- Rapid onset, severe symptoms, productive cough, dense CXR consolidation.
- Atypical Pneumonia
- Slower onset, less severe symptoms, less severe cough, minimal sputum, CXR (patchy/interstitial pattern)
- Community Acquired (<14d in hospital)
- Hospital Acquired (>14d)
- Typical Pneumonia
- Can sometimes narrow down to organism by symptoms and radiologic findings.
- On history/exam, inquire about:
- Cough - type of sputum (S. pneumon is rusty colored, red current jelly color is Klebsiella etc..)
- Chest discomfort
- Rigor - classically one teeth-chattering chill is Strep. pneumo.
- Shortness of breath
- Neck stiffness - r/o meningitis
- Chest Xray findings:
- Lobar Pneumonia
- Distinct anatomic segment of the lung. Respects anatomic boundaries (no proteases/hyaloronidases to break down tissue).
- S. pneumoniae, H. influenzae, Legionella
- Bronchopneumonia
- Originates in small ariways and spreads to adjacent ones. "Patchy infiltrates" that involve multiple areas of the lung and extend down bronchi.
- S.aureus, Gram negatives, Mycoplasma, Chlamydia, viruses
- Intersitial pneumonia
- Lung interstitium inflamed: fine diffuse grandular infiltrate.
- Influenza, CMV, Pneumocystis jirovecii, Miliary TB (micronodular infiltrates).
- Lung abscess
- Tissue necrosis, cavities with inflammatory fluid
- Anaerobics and S.aureus.
- Nodular Lesions
- Yeasts: (cryptococcus) Moulds (Histoplasmosis, coccidiomycosis) - nodular
- "Cannonball lesions" from hematogenous spread of endocarditis.
- Lobar Pneumonia
Gastroenteritis
- Virulence Factors: Enterotoxin, cytotoxin.
- Types:
- Watery Diarrhea (ETEC)
- Enterotoxigenic E.coli.
- Bloody Diarrhea (others)
- EHEC - Enterohemorrhagic E.coli (O157:H7) --> HUS.
- Salmonella
- Shingella
- Campylobacter
- Yersinia
- Watery Diarrhea (ETEC)
- Hemolytic Uremic Syndrome (HUS) --> E. coli O157:H7
- Fecal-Oral spread (contact)
Necrotizing Fasciitis
- Rapidly spreading, painful, infection of deep fascia + necrosis
- Pain out of proportion, beyond erythema, late findings (skin blue/black, bullae, gangrene, subq emphysema)
- Etiology:
- Type I : B-Hemolytic Strep (GAS?)
- Type II: Polymicrobial (less aggressive)
- Clinical diagnosis (can do hemostat)
- Tx:
- Resuscitation
- Surgical debridement, copius irrigation
- IV abx: penicillin 4million IU IV q4h or clindamycin 900 mg IV q6h
- Consult ID
Approach to Cellulitis
- Typically caused by S. aureus or GAS. Unless if Diabetes, can also be caused by anerobics.
- R/O MRSA, risk factors:
- Hospital Acquired MRSA (ICU or hospital stay)
- Community Acquired MRSA
- Community prevalence: i.e. Arizona (Most cellulitis is MRSA from abx overuse)
- Prison stay, or contact w prison stays
- Homeless
- Contact sports (Wrestling, Football)
- If suspicious for MRSA add Septra or Vancomycin. Can also use clindamycin, but ~10-20% MRSA resistance to clinda. Usually use clindamycin if toxic shock (stop protein synthesis to stop toxin production).
- If no improvement with 48h of ancef/keflex
- Abscess/Collection? - drain
- Free air? anaerobics gas prodcucing- do Xray to see pockets of air. Then cover for anaerobics.
- Foreign body - Xray
- Resistance (MRSA - check risk factors)
- Diabetes? - vascular insufficiency.
Comments