Aetiological diagnosis of brain abscesses and spinal infections: application of broad range bacterial polymerase chain reaction analysis

Abstract

Objective: To evaluate the usefulness of the broad range bacterial rDNA polymerase chain reaction (PCR) method combined with DNA sequencing in the aetiological diagnosis of intracranial or spinal infections in neurosurgical patients. Methods: In addition to conventional methods, the broad range bacterial PCR approach was applied to examine pus or tissue specimens from cerebral or spinal lesions in patients treated in a neurosurgical unit for a clinical or neuroradiological suspicion of bacterial brain abscess or spondylitis. Results: Among the 44 patients with intracranial or spinal lesions, the final diagnosis suggested bacterial disease in 25 patients, among whom the aetiological agent was identified in 17. A causative bacterial species was identified only by the rDNA PCR method in six cases, by both the PCR methodology and bacterial culture in six cases, and by bacterial culture alone in five. All samples in which a bacterial aetiology was identified only by the PCR approach were taken during antimicrobial treatment, and in three patients the method yielded the diagnosis even after > 12 days of parenteral treatment. One case also identified by the PCR approach alone involved a brain abscess caused by Mycoplasma hominis, which is not readily cultured by routine methods. Conclusions: In patients with brain abscesses and spinal infections, the broad range bacterial rDNA PCR approach may be the only method to provide an aetiological diagnosis when the patient is receiving antimicrobial treatment, or when the causative agent is fastidious.

Detection of a Mixed Infection in a Culture-Negative Brain Abscess by Broad-Spectrum Bacterial 16S rRNA Gene PCR

“…Bacterial 16S rRNA gene PCR often outperforms anaerobic culture in the detection of fastidious and anaerobic pathogens in brain abscess material (7,10,11). This may be explained due to the difficult and time-critical sample treatment in plating for anaerobic cultures.…”

Spinal infections due to Eikenella corrodens: Case report and literature review

“…This may be one of the reasons why Eikenella is rarely identified or associated with spinal infections. The eubacterial PCR method represents a supplementary diagnostic tool in cases of fastidious growth bacteria, particularly if the diagnostic sampling is performed under empiric antibiotic therapy [14,15].…”

An overview on the application of Polymerase Chain Reaction (PCR) in the diagnosis of bacterial infections

“…Brain abscess is caused by Mycoplasma hominis and are only identified by PCR. Based on this study, it was found that for patients with brain abscesses and spinal infections, the broad range bacterial rDNA PCR approach may be the only method to provide an aetiological diagnosis when the patient is receiving antimicrobial treatment, or when the causative agents are small to be detected by culture method (Kupila et al 2003). …”