Is metagenomic sequencing better than conventional tests for pediatric infectious disease?

Conventional tests often miss infections in children because samples are small and symptoms are vague. Metagenomic next-generation sequencing (mNGS) looks for genetic material from many germs at once without needing a specific guess. Research shows mNGS detects infections much more often than standard culture methods in pediatric patients.

What the research says

A large review of 4,165 children found that mNGS had a sensitivity of 84% compared to only 40% for conventional microbiological tests. This means mNGS correctly identified the infection in 84 out of 100 cases where it was present, while conventional tests missed 60% of those cases ². The ability to find the right germ was significantly better with mNGS, which helped doctors distinguish between actual infections and other lung problems ⁴.

In a study of 29 children with severe infections, mNGS found pathogens in 69% of cases while conventional culture only found them in 7%. Standard tests failed to detect viruses and fungi that mNGS could identify ⁵. Another study noted that mNGS could identify the specific germ causing an infection about two days earlier than traditional methods ⁶.

Despite the higher detection rate, mNGS is not perfect. In some real-world cases, mNGS found germs that were not actually causing the illness, leading to a lower agreement with the final clinical diagnosis compared to positive results ⁶. Because of this, doctors must combine mNGS results with the patient's overall condition and other test data before starting treatment.

What to ask your doctor

• How does the higher detection rate of mNGS change the treatment plan for my child?
• Could the germs found by mNGS be harmless background noise rather than the cause of the infection?
• How quickly can we get results from mNGS compared to standard culture tests?
• What other tests do we need to confirm that the identified pathogen is causing the symptoms?