Tropheryma whipplei and Giardia intestinalis Co-Infection: Metagenomic Analysis During Infection and the Recovery Follow-Up

Abstract

Background: Whipple's disease (WD) is a rare infection caused by Tropheryma whipplei. Diagnosis is challenging and requires a combination of several data sets, such as patient history, clinical and laboratory investigations, and endoscopy with histology analyses. While persistent diarrhea is a common symptom, WD can affect multiple organs.

Case description: We present the case of a 66-year-old immunocompetent patient with WD and a history of Helicobacter pylori infection who developed chronic diarrhea. Colonoscopy and histopathological analysis revealed the presence of foamy macrophages with periodic acid-Schiff-positive particles. Subsequently, molecular methods confirmed the clinical WD diagnosis and metagenomic analyses further identified a co-infection with Giardia intestinalis. The patient fully recovered after 14 months of antibiotic therapy. During pharmacological treatment, clinical and laboratory follow-ups were conducted at 6 and 12 months, and microbiome profiles were also analyzed to identify the most abundant species in the samples.

Conclusion: The metagenomic analyses showed the eradication of the two pathogens and a progressive restoration to a healthy/balanced status after antibiotic therapy.

Keywords: Whipple’s disease (WD); bioinformatics; gut microbiome; metagenomic analyses; next-generation sequencing (NGS).

Figure 1

Sankey diagrams of the microorganisms found in the T0 (a), FU1 (b), and FU2 (c) samples. The top 10 species are represented for each sample. The most abundant species are shown in highlighted areas.

Figure 1

Sankey diagrams of the microorganisms found in the T0 (a), FU1 (b), and FU2 (c) samples. The top 10 species are represented for each sample. The most abundant species are shown in highlighted areas.