Respiratory
Image Set 11 - (Sparrow 7IIC2) Moraxella catarrhalis, Haemophilus, and S. pneumoniae pneumonia
Results: 0-2 Sq. Epith./lpf || 30-40 WBC's/hpf || Numerous gram negative diplococci || Numerous gram positive diplococci || Few small gram negative rods
Note: The gram stain description "gram positive diplococci" indicates the possibility of Streptococcus pneumoniae present in the specimen. Look closely at these organisms with the light source turned down slightly. A capsule can be seen around the organism. This halo-like capsule is more supportive of S. pneumoniae. A Quellung test would be useful at this point in confirming the diagnosis. The Haemophilus is hard to see because of the predominance of the gram negative diplococci. Look closely for the small gram negative rods.
KEY POINTS: Moraxella catarrhalis is a gram negative diplococcus that resembles non-pathogenic Neisseria both morphologically and metabolically. It is considered to be a part of the normal oropharyngeal flora, but can become pathogenic causing severe meningitis and endocarditis, as well as sinusitis, otitis media, and lower respiratory tract infections.
Moraxella catarrhalis, Haemophilus, and S. pneumoniae 01
Moraxella catarrhalis, Haemophilus, and S. pneumoniae 02
Moraxella catarrhalis, Haemophilus, and S. pneumoniae 03
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