Meningitis caused by Porphyromonas endodontalis detected by PCR amplification and sequencing of 16S rRNA genes direct from cerebrospinal fluid and cerebral tissue

Abstract

Introduction: Porphyromonas endodontalis (formerly Bacteroides endontalis) is a blackpigmented, non-motile, obligate anaerobe. It has an established role in endodontal infections and has rarely been isolated from other sites. To the best of our knowledge, this is the first time that this organism has been detected as the sole cause of meningitis. This was made possible by the use of direct-on-sample 16S rRNA gene amplification and sequencing. Case presentation: We present a case of meningitis that progressed to a cerebral abscess in an elderly but otherwise immunocompetent male. Despite broad-spectrum antibiotic therapy, the patient died. Conclusion: Although anaerobic meningitis is rarely described, it should be considered if there are clinical and biochemical features of meningitis but no organism isolated on standard aerobic culture.

Oral flora meningoencephalitis diagnosis by next-generation DNA sequencing

“…Bacterial meningitis remains a significant cause of morbidity and mortality despite the fact that its rates have dropped significantly in regions with successful implementation of vaccination campaigns against Streptococcus pneumonia and type B Haemophilus influenzae [ 1, 2 ]. Meningitis or encephalitis due to seeding of the CNS with common oral [ 3–7 ] or colonic [ 8, 9 ] floral anaerobic organisms has been described before in case reports, but the application of next-generation sequencing to clinical specimens has made aetiological identifications possible in highly polymicrobic, culture-negative, bacterial meningitis cases, such as presented with our patient. The methods of the specific assay performed by a reference laboratory in our case, and the application of these methods to polymicrobial infections in general, was recently reported [ 10 ] and included 16S rRNA deep sequencing (Illumina MiSeq) utilizing the primers and databases published previously [ 11 ] (primers available in an open access supplementary file).…”

IDENTIFIKASI BAKTERI PORPHYROMONAS ENDODONTALIS PADA INFEKSI SALURAN AKAR MELALUI ANALISIS GEN 16S rRNA

“…5 Bakteri ini akan membentuk koloni yang konveks, halus mengkilat, dan berdiameter 1-2 mm dengan koloni berwarna hitam kecoklatan. 7 Namun demikian pewarnaan Gram pada kedua sampel pada penelitian ini masih memperlihatkan berbagai jenis bakteri yang heterogen dan belum memperlihatkan kultur murni bakteri P. endodontalis.…”

“…5,6 Pada tahun 2015 terdapat literatur pertama yang melaporkan kehadiran Porphyromonas endodontalis pada penyakit meningitis yang ditemukan dengan menggunakan metode analisis gen 16S rRNA pada sampel. 7 Selain itu meskipun bakteri ini tidak memiliki prevalensi yang tinggi pada infeksi sekunder saluran akar seperti pada Enterococcus faecalis, namun Liljestrand dkk (2016), menyatakan bahwa Porphyromonas endodontalis yang ditemukan dalam rongga mulut dapat berperan menyebabkan penyakit sistemik serta mampu menginvasi sel-sel endotel arteri jantung. 8,9 Bakteri pigmen hitam atau black-pigmented bacteria (BPB) memberikan tantangan dalam teknik kultur secara konvensional dikarenakan kulturisasi dengan lingkungan anerobik obligat sangat memakan waktu dan memerlukan kondisi kultur yang sangat rumit.…”