Which of the following pleomorphic coccobacillus shows satellite phenomenon in blood agar?
High-Yield Explanation
Haemophilus influenzae is a small (1- by 0.3-mm) gram-negative organism of variable shape; hence, it is often described as a pleomorphic coccobacillus. On chocolate agar, flat, grayish brown colonies with diameters of 1-2 mm are present after 24 hours of incubation. H influenzae does not grow on sheep blood agar except around colonies of staphylococci "satellite phenomenon". Ref: (2013). Chapter 18. Haemophilus, Bordetella, Brucella, and Francisella. InBrooks G.F., Carroll K.C., Butel J.S., Morse S.A., Mietzner T.A. (Eds), Jawetz, Melnick, & Adelberg's Medical Microbiology, 26e.