Slide 2. Haemophilus influenzae
Many coccobacilli are present in the cytoplasm of the neutrophils, a common site for Haemophilus influenzae in sputum stains. The examiner should always look carefully for organisms in white cells. (An alveolar macrophage is also present on this slide.)

Slide 3. Neisseria meningitidis
Numerous gram-negative diplococci are present, singly and in pairs. In patients with pneumonia, the respiratory pathogens most likely to have this appearance are Neisseria meningitidis or Moraxella (Branhamella) catarrhalis which look alike. Other gram-negative diplococci, such as commensal Neisseria species or Veillonella species, are rarely the sole or predominant organism in sputum smears of patients with pneumonia.

Slide 4. Moraxella (Branhamella) catarrhalis
Moraxella catarrhalis can cause pneumonia, especially in patients with alcoholism or chronic obstructive lung disease. This slide shows many gram-negative cocci, singly and in pairs. Like meningococci and Haemophilus influenzae, Moraxella catarrhalis is often visible within the cytoplasm of neutrophils.