Case 74. Haemophilus influenzae infection of pharynx (25 y-o M)
         
   
Painful pharyngeal ulcer biopsied from a febrile young adult
   
         
   
Key words : Haemophilus influenzae, pharyngeal ulcer
   
     
 
     
Onto the ulcer base, thick bacterial colonies are attached (HE, low power).   The colony is mainly composed of lightly basophilic rods (HE, oil immersion).
     
 
     
The rods are Gram-negative, while Gram-positive cocci are focally co-infected (Gram).   Reference case 74A
Neonatal pneumonia caused by Haemophilus influenzae infection (HE). Exudation of neutrophils, fibrin and red cells is seen in the bronchiolar lumen, while interstitial change with hyaline membrane formation is observed in the surrounding lung tissue. No pathogens are recognizable.