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Published on: November 5, 2019
Meningitis due to an unusual type of Haemophilus influenzae
Abstract:
An infant was admitted to hospital with suspected meningitis. Haemophilus influenzae type 'a' was isolated from cerebrospinal fluid (C.S.F.) and blood. Haemophilus meningitis due to types other than type 'b' is rare, and only a few due to type 'a' have so far been recorded. Investigations of the family are included together with a discussion of the implications for the diagnostic bacteriologist.
Insights
A rare case of Haemophilus influenzae type a meningitis in an infant is presented. This finding highlights the importance of considering non-typeable strains in diagnosing bacterial meningitis.
Area of Science:
- Pediatrics
- Infectious Diseases
- Bacteriology
Background:
- Meningitis is a serious infection of the membranes surrounding the brain and spinal cord.
- Haemophilus influenzae type b (Hib) was a common cause of bacterial meningitis in children before widespread vaccination.
- Infections caused by non-typeable or other serotypes of Haemophilus influenzae are less common.
Observation:
- An infant presented with symptoms suggestive of meningitis.
- Cerebrospinal fluid (C.S.F.) and blood samples were collected for analysis.
- Haemophilus influenzae type a was identified as the causative agent.
Findings:
- This case represents a rare instance of Haemophilus meningitis caused by type a.
- Few cases of Haemophilus influenzae type a meningitis have been previously documented.
- The study includes family investigations, providing epidemiological context.
Implications:
- The diagnostic bacteriologist must be aware of the possibility of rare serotypes causing meningitis.
- This case underscores the need for broad diagnostic capabilities beyond common pathogens.
- Further research into the epidemiology and clinical presentation of non-type b Haemophilus influenzae meningitis is warranted.
Related Concept Videos
Bacterial Meningitis
Viral Meningitis
Cryptococcal Meningitis
Bacterial Meningitis I: Introduction
Bacterial Meningitis II: Pathophysiology
Encephalitis l: Introduction

