# Diagnosis of secondary tuberculosis infection in an asymptomatic elderly with cancer using next-generation sequencing: Case report

## TL;DR

A case report shows how next-generation sequencing helped diagnose tuberculosis in an elderly cancer patient who had no symptoms.

## Contribution

Highlights the use of mNGS for detecting occult TB in asymptomatic, high-risk cancer patients.

## Key findings

- mNGS identified Mycobacterium tuberculosis in an asymptomatic elderly cancer patient.
- The case suggests cancer may create immune conditions that reactivate latent TB.
- mNGS proves effective as a rapid diagnostic tool for hidden infections in high-risk groups.

## Abstract

In recent years, there has been a notable increase in the prevalence of tumors and tuberculosis (TB), particularly among elderly and immunocompromised populations. Early diagnosis and treatment are crucial for significantly improving patient outcomes. However, traditional diagnostic methods exhibit certain limitations. The rapid advancement of metagenomic next-generation sequencing (mNGS) has shown promising applications in the field of infectious diseases. We describe an 88-year-old male with multiple comorbidities, including newly diagnosed localized prostate cancer, who presented asymptomatically. Routine mNGS screening unexpectedly identified Mycobacterium tuberculosis, suggesting that malignancy may foster immune conditions favoring latent TB reactivation. This case emphasizes mNGS’s role as a rapid, sensitive diagnostic adjunct for occult infections in high-risk populations.