PMC7491934_01
Beaded Gram-positive bacilli (arrow) in Gram-stained smear from positive blood culture bottle (magnification: x1000).
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F1
A blood culture bottle (BACTEC 9120; BD) inoculated with venous blood collected with aseptic techniques was positive after 13 h of aerobic incubation, and a Gram-stained smear from the bottle showed Gram-positive bacilli (Fig. 1).
Colonies of 
Mycobacterium chelonae
 on MacConkey agar after 48 h of aerobic incubation at 28  C.
acmi-1-069-g002.jpg
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F2
On subcultures, white to pale, smooth colonies, 2-3 mm in diameter on blood agar (HiMedia Laboratories) and small, pink colonies on MacConkey agar (HiMedia Laboratories) were obtained after 72 h of aerobic incubation (Fig. 2).
Gram-stained smear prepared from colonies on MacConkey agar showing beaded Gram-positive bacilli (magnification: x1000).
acmi-1-069-g003.jpg
PMC7491934_01_acmi-1-069-g003.jpg
F3
Gram staining and ZN staining of smears prepared from colonies on MacConkey agar showed beaded Gram-positive and acid-fast bacilli, respectively (Figs 3 and 4).
Ziehl-Neelsen staining of colonies on MacConkey agar showing beaded acid-fast bacilli (magnification: x1000).
acmi-1-069-g004.jpg
PMC7491934_01_acmi-1-069-g004.jpg
F4
Gram staining and ZN staining of smears prepared from colonies on MacConkey agar showed beaded Gram-positive and acid-fast bacilli, respectively (Figs 3 and 4).