A Case of Aggregatibacter aphrophilus Multiple Abscess

Area of Science:

• Infectious Diseases
• Microbiology
• Neurology

Background:

• Aggregatibacter aphrophilus is a member of the HACEK group, known for causing endocarditis.
• Abscess formation in the brain and lungs by A. aphrophilus is rare, particularly in asplenic individuals without endocarditis.

Purpose of the Study:

• To report a rare case of disseminated infection caused by A. aphrophilus.
• To highlight the diagnostic utility of 16S rDNA PCR in cases with negative conventional cultures.
• To document the successful treatment of A. aphrophilus abscesses with cefotaxime.

Main Methods:

• Case report of a 43-year-old male with a history of splenectomy and drug addiction.
• Diagnosis confirmed by 16S rDNA PCR analysis of abscess fluid, as initial microbiological samples were negative.
• Treatment administered with cefotaxime.

Main Results:

• The patient presented with brain and lung abscesses.
• Conventional microbiological cultures were negative.
• 16S rDNA PCR successfully identified A. aphrophilus in the abscess fluid.
• Clinical symptoms resolved within six weeks of cefotaxime therapy.

Conclusions:

• Aggregatibacter aphrophilus can cause severe disseminated infections, including brain and lung abscesses, even in the absence of endocarditis.
• 16S rDNA PCR is a valuable tool for diagnosing infections caused by fastidious or difficult-to-culture organisms like A. aphrophilus.
• Cefotaxime is an effective treatment for A. aphrophilus-induced abscesses.