12 results
Microorganisms Responsible for Infective Endocarditis

Native valves:
 - Streptococcus viridans 
 - Enterococci 
 - Other streptococci
Responsible for Infective ... bacilli - Fungi (Candida ... , Aspergillus, Histoplasma ... ) - Culture negative ... negative #Infective
My Patient with Infective Endocarditis (IE) Has Negative Blood Cultures
 - Did they receive antibiotics prior
My Patient with Infective ... Blood Cultures ... Fungal (Histoplasma/Aspergillus ... patient a surgical candidate ... Ahmed_HBabiker #Infective
Causes of blood culture negative infective endocarditis

Bartonella spp, Brucella spp, Coxiella burnetii, Chlamydia spp, Tropheryma whipplei,
Causes of blood culture ... negative infective ... whipplei, Fungi (Aspergillus ... , Candida), Mycoplasma ... #negative #Endocarditis
Blood Culture-Negative Infective Endocarditis (BCNIE)
Definition: No etiology found after 3 separate blood cultures remain negative for
Blood Culture-Negative ... remain negative ... whipplei, Fungi (Aspergillus ... , Candida), Mycoplasma ... #BloodCulture #Negative
Causes of Dysuria - Differential Diagnosis Algorithm
Pyuria - Leukocytes on Dipstick/Microscopy
 - Bacteriuria & Hematuria -
Leukocytes on Dipstick/Microscopy ... Urinary Tract Infection ... Urinary Tract Infection ... Hematuria - Dipstick negative ... Vaginitis • Candida
Tuberculosis Testing

LATENT TB
• LTBI is diagnosed when an asymptomatic patient has a positive TST or IGRA
developing active infection ... • Tuberculosis infection ... TB AFB smear microscopy ... because false-negative ... Mycobacterial culture
Fungal Biomarkers: Beta-D-Glucan and Aspergillus Galactomannan
Beta-D-Glucan:
 • Polysaccharide cell wall component of many fungi
 • Pathogens:
• Pathogens: Candida ... , Aspergillus ... Coccidioides - Negative ... invasive fungal infection ... Cryptococcus - Negative
Endocarditis Summary

Who?
Infectious:
• Pre-existing valvular disease
• Prosthetic valve
• Congenital heart disease
• IV substance use
• IV catheter
• Recent
Hypercoagulable (APLAS ... 90% of IE cases Culture ... • Coagulase-negative ... Tropheryma Whipplei • Aspergillus ... • Blood cultures
Important Fungal Stains
Mycology Lab:
 • Calcofluor white - Fluorochrome that binds glucans and chitin in fungal
preparation from culture ... exceptions are Aspergillus ... • India ink - "Negative ... #microbiology #microscopy
Causes of Myocarditis 
1. Infectious Myocarditis
 • Bacterial - Staphylococcus, Streptococcus, Pneumococcus, Meningococcus, Gonococcus, Salmonella, Corynebacterium
) • Fungal - Aspergillus ... , Blastomyces, Candida ... Autoantigens - Infection-negative ... lymphocytic, infection-negative