Case Report
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Dec 26, 2018; 6(16): 1169-1174
Published online Dec 26, 2018. doi: 10.12998/wjcc.v6.i16.1169
Spontaneous cerebral abscess due to Bacillus subtilis in an immunocompetent male patient: A case report and review of literature
Ioannis Tsonis, Lydia Karamani, Panagiota Xaplanteri, Fevronia Kolonitsiou, Petros Zampakis, Georgios Gatzounis, Markos Marangos, Stelios F Assimakopoulos
Ioannis Tsonis, Lydia Karamani, Georgios Gatzounis, Department of Neurosurgery, University of Patras Medical School, Patras 26504, Greece
Panagiota Xaplanteri, Fevronia Kolonitsiou, Department of Microbiology, University of Patras Medical School, Patras 26504, Greece
Petros Zampakis, Department of Radiology, University of Patras Medical School, Patras 26504, Greece
Markos Marangos, Stelios F Assimakopoulos, Department of Internal Medicine, Division of Infectious Diseases, University of Patras Medical School, Patras 26504, Greece
Author contributions: Tsonis I and Gatzounis G were the patient’s neurosurgeons, reviewed the literature and contributed to manuscript drafting; Karamani L reviewed the literature and contributed to manuscript drafting; Xaplanteri P and Kolonitsiou F performed the microbiological analyses and interpretation and contributed to manuscript drafting; Zampakis P analyzed and interpreted the imaging findings; Marangos M and Assimakopoulos SF performed the infectious diseases consultation, reviewed the literature and drafted the manuscript; Assimakopoulos SF, Marangos M and Gatzounis G were responsible for the revision of the manuscript for important intellectual content; all authors issued final approval for the version to be submitted.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2013), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author to: Stelios F Assimakopoulos, MD, PhD, Assistant Professor, Department of Internal Medicine, Division of Infectious Diseases, University of Patras Medical School, Patras 26504, Greece. sassim@upatras.gr
Telephone: +30-2610-999583 Fax: +30-2610-993982
Received: October 4, 2018
Peer-review started: October 4, 2018
First decision: October 25, 2018
Revised: October 30, 2018
Accepted: November 7, 2018
Article in press: November 7, 2018
Published online: December 26, 2018
Processing time: 81 Days and 10.8 Hours
Abstract
BACKGROUND

Bacillus subtilis (B. subtilis) is considered a non-pathogenic microorganism of the genus Bacillus and a common laboratory contaminant. Only scarce reports of B. subtilis central nervous system infection have been reported, mainly in the form of pyogenic meningitis, usually in cases of direct inoculation by trauma or iatrogenically.

CASE SUMMARY

A 51-year-old man, with a free previous medical history, presented to the Emergency Department of our hospital complaining of recurrent episodes of left upper limb weakness, during the last month, which had been worsened the last 48 h. During his presentation in Emergency Department he experienced a generalized tonic-clonic grand mal seizure. Brain magnetic resonance imaging (MRI) scan with intravenous Gadolinium revealed a 3.3 cm × 2.7 cm lesion at the right parietal lobe surrounded by mild vasogenic edema, which included the posterior central gyrus. The core of the lesion showed relatively homogenous restricted diffusion. Post Gadolinium T1W1 image, revealed a ring-shaped enhancement. Due to the imaging findings, brain abscess was our primary consideration. Detailed examination for clinical signs of infectious foci revealed only poor oral hygiene with severe tooth decay and periodontal disease, but without detection of dental abscess. The patient underwent surgical treatment with right parietal craniotomy and total excision of the lesion. Pus and capsule tissue grew B. subtilis and according to antibiogram intravenous ceftriaxone 2 g bids was administered for 4 wk. The patient remained asymptomatic and follow-up MRI scan two months after operation showed complete removal of the abscess.

CONCLUSION

This case highlights the ultimate importance of appropriate oral hygiene and dental care to avoid potentially serious infectious complications and second, B. subtilis should not be considered merely as laboratory contaminant especially when cultivated by appropriate central nervous system specimen.

Keywords: Bacillus subtilis; Brain abscess; Central nervous system infection; Craniotomy; Meningitis; Case report

Core tip: Bacillus subtilis (B. subtilis) is considered a non-pathogenic microorganism of the genus Bacillus and a common laboratory contaminant. We present herein, a rare case of spontaneous cerebral abscess caused by B. subtilis, evolved in a previously healthy immunocompetent male patient. B. subtilis was isolated from both the capsule and pus of the surgically excised brain abscess. Severe tooth decay and periodontitis were the only potential infectious foci. This case highlights the ultimate importance of appropriate oral hygiene and dental care to avoid potentially serious infectious complications and second, B. subtilis should not be considered merely as laboratory contaminant especially when cultivated by appropriate central nervous system specimen.