27 results
Microorganisms Responsible for Infective Endocarditis

Native valves:
 - Streptococcus viridans 
 - Enterococci 
 - Other streptococci
Histoplasma) - Culture ... negative bacilli ... streptococci - Culture ... Pathogens #Diagnosis #Differential ... #InfectiousDiseases
Causes of blood culture negative infective endocarditis

Bartonella spp, Brucella spp, Coxiella burnetii, Chlamydia spp, Tropheryma whipplei,
negative infective ... BCNIE #Causes #differential ... #negative #Endocarditis ... #InfectiousDiseases ... #CNIE #BCNIE #cardiology
Blood culture contaminants
Grouped by gram negative vs gram positive vs other as well as never/maybe/probably
Some additional
Blood culture contaminants ... Grouped by gram negative ... febrilepodcast] #ID #Infectious ... Diseases #Infections ... Microbiology #Micro #Differential
Causes of Culture Negative Abscess - Differential Diagnosis Framework
Consider prior antibiotics as a cause of a
- Differential ... Dracunculiasis - Non-Infectious ... Blastomycosis - Non-Infectious ... #Differential # ... Diagnosis #InfectiousDiseases
Blood Culture-Negative Infective Endocarditis (BCNIE)
Definition: No etiology found after 3 separate blood cultures remain negative for
Blood Culture-Negative ... remain negative ... #BloodCulture #Negative ... Endocarditis #diagnosis #differential ... #workup #infectiousdiseases
Endocarditis Algorithm - Infective vs Noninfective Causes
Noninfective:
 • Malignancy
 • Autoimmune disease
 • Systemic infection
Native Valve
disease • Systemic infection ... • HACEK • Culture-negative ... epidermidis • Gram-negative ... Enterococcus • Gram-negative ... Noninfective #Causes #Differential
Tuberculosis Testing

LATENT TB
• LTBI is diagnosed when an asymptomatic patient has a positive TST or IGRA
because false-negative ... Mycobacterial culture ... Liquid and solid cultures ... Mycobacterial culture ... LatentTB #ActiveTB #InfectiousDiseases
Bandemia Overview

Normal: < 1%
Clinically significant: > 10%

Band neutrophils are slightly less mature than segmented neutrophils and
Neutrophil (Normal) Differential ... overlook severe infections ... likelihood of negative ... relative to both ... #Bandemia #differential
Bacteremia Quick Reference - Treatment Duration

Gram Negative Bacteremia:
 • Avoid: Aminoglycosides and tigecycline
 • Catheters should
Duration Gram Negative ... thrombophlebitis, IE, infection ... are negative ... of metastatic infection ... Management #Duration #infectiousdiseases
Causes of Relative Bradycardia - Note the propensity for intracellular organisms.
Infectious: 
Legionella, Psittacosis, Q fever, Typhoid
Causes of Relative ... Infectious: Legionella ... spotted fever, Non-infectious ... bradycardia #Causes #differential ... #diagnosis #infectiousdiseases