Miselleneoud bacteria Flashcards
Etiologic agent for rat-bite fever and Haverhill fever in humans
- Gram-negative bacillus that requires media containing blood, serum or ascites fluid
Streptococcus moniliformis
Known to develop L forms (bacteria without cell wall)
Streptococcus moniliformis
Shows extreme pleomorphism with long, looped, filamentous forms, chains and swollen cells –
highly pleomorphic bacteria
- Tendency to form long chains of bacilli with prominent yeast-like swelling described as
―”necklace-like, string of pearls or string of beads’
Streptococcus moniliformis
Non-encapsulated, non-hemolytic, non-motile, facultatively anaerobic
- Normally found in the oropharynx of wild and laboratory rats
Streptococcus moniliformis
stain is required to demonstrate the L-form colonies
Dienes stain
stain also reveals the bacteria when gram stain fails due to lack of cell wall
constituents
Acridine orange
Transmitted by 2 routes
Rat bite or by direct contact with rats
o By ingestion of contaminated food like unpasteurized milk or milk products and water
In broth cultures, organism grows as “puff balls of bread crumbs” near the bottom of the tube or
on the surface of the sedimented RBC in blood culture media
Streptococcus moniliformis
Colonies embedded in the agar may exhibit a “fried egg” appearance with a dark center a a
flattened, lacy edge.
Streptococcus moniliformis
Etiologic agent of bacterial vaginosis, considered a sexually transmitted disease
- It is part of the normal flora of anorectal adult
- Small, pleomorphic gram-variable or gram-negative coccobacilli or short rods; non-motile
- Colonies are small and B-hemolytic on media containing rabbit or human blood
- Oxidase and catalase negative
Gardnerella vaginalis
Etiologic agent of bacterial vaginosis, considered a sexually transmitted disease
- It is part of the normal flora of anorectal adult
- Small, pleomorphic gram-variable or gram-negative coccobacilli or short rods; non-motile
- Colonies are small and B-hemolytic on media containing rabbit or human blood
- Oxidase and catalase negative
Gardnerella vaginalis
large squamous epithelial cells with numerous attached
small rods
(+) clue cells
– vaginal secretions plus 1 drop of 10% KOH (pH
>4.5)
whiff test- (+) fishy amine odor
found in middle-aged men characterized by the presence of PAS staining
macrophages
Whipple‘s disease
Gram (+) actinomyces, not closely related to any other genus known to cause infection
- This microorganism cannot be cultured, it can be seen in macrophages but cannot be cultured
Tropheryma Whippelii
