Case Report: Pneumonia Caused by Chlamydia Psittaci and Cryptococcus Co-Infection

Area of Science:

• Infectious Diseases
• Microbiology
• Genomics

Background:

• Zoonotic diseases pose a significant public health threat, often originating from animal reservoirs.
• Co-infections with multiple pathogens can complicate diagnosis and treatment.
• Metagenomic next-generation sequencing (mNGS) offers a powerful tool for identifying novel and complex infectious agents.

Observation:

• A patient with chronic hepatitis B presented with fever and productive cough, symptoms suggestive of pneumonia.
• The patient had contact with a stray pigeon prior to illness onset.
• Clinical presentation indicated a potential zoonotic transmission event.

Findings:

• Metagenomic next-generation sequencing (mNGS) confirmed a rare co-infection of Chlamydia psittaci and Cryptococcus species.
• Chlamydia psittaci, a bacterium, and Cryptococcus, a fungus, were identified as the causative agents of pneumonia.
• The patient's underlying chronic hepatitis B may have influenced susceptibility or disease presentation.

Implications:

• This case underscores the potential for zoonotic transmission of multiple pathogens, including Chlamydia psittaci and Cryptococcus, from avian sources like pigeons.
• The successful diagnosis and treatment highlight the critical role of advanced molecular techniques like mNGS in identifying complex co-infections.
• Clinical awareness of zoonotic co-infections is crucial for timely and effective patient management, particularly in immunocompromised individuals.