Diagnosis of Chagasic Encephalitis by Sequencing of 28S rRNA Gene

Abstract

We report a case of chagasic encephalitis diagnosed by 28S rRNA sequencing. The diagnosis of chagasic encephalitis is challenging, given the broad differential diagnosis for central nervous system lesions in immunocompromised patients and low sensitivity of traditional diagnostics. Sequencing should be part of the diagnostic armamentarium for potential chagasic encephalitis.

Keywords: 28S rRNA gene; Chagas disease; HIV/AIDS and other retroviruses; Trypanosoma cruzi; chagasic encephalitis; immunocompromised; meningitis/encephalitis; parasites; protozoa; rRNA sequencing.

Figure 1

Images obtained during diagnosis of chagasic encephalitis in 31-year-old man in the United States. A) Contrast-enhanced T1-weighted magnetic resonance imaging of the brain showing a cerebral tumor-like chagoma in the axial plane. B) Follow-up contrast-enhanced T1-weighted magnetic resonance imaging obtained ≈8 weeks later showing improvement of the chagoma.

Figure 2

Tissues obtained during diagnosis of chagasic encephalitis in 31-year-old man in the United States. Touch preparation of brain tissue showing necrotizing encephalitis and abundant Trypanosoma cruzi amastigotes with prominent kinetoplasts (arrows) in astrocytes and macrophages (hematoxylin and eosin stain, original magnification ×600).

Figure 3

Sequences obtained during diagnosis of chagasic encephalitis in 31-year-old man in the United States. Alignment of amplicon sequence isolated from the patient was compared with a reference Trypanosoma cruzi 5.8S rRNA internal transcribed spacer sequence (GenBank accession no. L22334.1). Percentage identity was 98.9% (346/350 bases). Hyphens indicate gaps in the genome.