gram-variable


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gram-variable

gram-positive bacteria that can become gram-negative after culturing.
References in periodicals archive ?
The only culture information available on the day of discharge was that a Gram-variable rod had grown aerobically on sheep blood agar plates as well as a yeast.
gram-variable morphophytes morphophytes rods Points 4+ 0 0 0 3+ 1+ 1+ or 2+ 1 2+ 2+ 3+ or 4+ 2 1+ 3+ 3 0 4+ 4 Review each of the first 3 columns in turn, assigning points at far right according to your exam findings.
A gram-stained smear will show an altered vaginal flora, one filled with pleomorphic gram-negative to gram-variable rods and lacking in the normally present gram-positive lactobacilli.
After 4 days, a gram-variable polymorphic rod, named nimes373, grew from both aerobic culture vials and yielded very small polymorphic colonies on Columbia sheep blood and blood-chocolate agar plates (Bio-Rad, Marnes-la-Coquette, France).
4,10] Cells with variable wall thickness (eg, dividing cells and those undergoing autolysis) tend to yield a Gram-variable stain result.
A smear of uneven thickness will result in uneven staining and Gram-variable organisms [4]
To the Editor: Streptobacillus moniliformis is a facultatively anaerobic, pleomorphic, gram-variable bacillus often seen in chains and as long unbranched filaments.
In 2 published outbreaks, the Brucella isolate resisted decoloration and appeared as a gram-positive or gram-variable coccobacillus and thus was misidentified as micrococcus or a coryneform bacillus (14,29).
Initial isolates from blood cultures of an index patient and two laboratory workers were incorrectly identified as contaminants, in part because of reporting of primary Gram stain results as gram-positive and gram-variable.
Overnight aerobic culture grew small gray colonies (<1 mm in diameter) of non-spore-forming gram-variable bacilli (1 [micro]m x 5 [micro]m), which, on subculture anaerobically grew gram-positive rods with oval, terminal spores.
For the remaining 22 reports of gram-positive bacilli, 16 were identified as Corynebacteriurn, 1 as Proprionobacterium, 1 as Clostridium, 1 as Eubacterium, and 1 as Staphylococcus hominis; 1 was a mixed infection with gram-positive organisms, and 1 was an unidentified motile gram-variable bacillus.
Con respecto al diagnostico de la entidad, el patron de oro es la coloracion de Gram, aplicando el puntaje de Nugent (22, 23), el cual consiste en una cuantificacion ponderada de los siguientes morfotipos: lactobacilos, Gardnerella vaginalis o bacteroides, y bacilos Gram-variables curvos; considerando normal la presencia de lactobacilos y anormal la presencia de los otros morfotipos (22).