A 2-year-old child is brought to the emergency with history offerer and vomiting. On examination he has neck rigidity. The CSF examination shows polymorphs more that 2000/m> I protein 100 mg/dl and glucose 10 mg/dl. The Gram stain shows the presence of Gram negative coccobacilli. The culture shows growth of bacteria only on chocolate agar and not on blood agar. The causative agent is: (A) Neisseria meningitides, (B) Haemophilus influenzae., (C) Branhamella catarrhalis., (D) Legionella pneumophila.
Answer is B. (B) Haemophilus influenzae. # Meningitis: This is the most serious disease produced by H. influenzae with case fatality rates up to 90 per cent in the untreated.> Bacilli reach the meninges from the nasopharynx through the bloodstream.> Disease is more common in children between two months and three years of age.> Age incidence has been correlated with the absence of bactericidal anti-PRP antibodies.> Older children develop immunity as a result of subclinical infection.> It has been reported that in the tropics, non-type b strains may be responsible for meningitis more often than in the temperate zcnes.