2025/03/19 by Simone E. Adams, Carole Kebbi‐Beghdadi, Mirja Puolakkainen +2 · 1 voice
Biochemistry, Genetics and Molecular Biology · Medicine · #Amoebic Infections and Treatments #Heme Oxygenase-1 and Carbon Monoxide #Legionella and Acanthamoeba research
paper · doi:10.1099/jmm.0.001953
openalex publication_date 2025/03/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Graphical abstract Parachlamydia acanthamoebae is an obligate intracellular bacterium found in free-living Acanthamoeba amoebae. As with other Chlamydiales, P. acanthamoebae has a biphasic lifecycle with an infectious elementary body and a replicative reticulate body. Once inside a host, the elementary body differentiates to the reticulate body to undergo replication within the membrane-bound compartment called the inclusion. These infected amoebae can be found in many environments such as in hospitals, household water sources, lakes and farm animals. Although the exact route of transmission from amoebae to humans is unknown, it is believed that humans may breathe in the Parachlamydia -infected amoebae. The amoebae can then reside on the respiratory epithelium within the new human host. It is possible that newly released P. acanthamoebae can then directly infect human host cells, such as macrophages, pneumocytes or lung fibroblasts, or propagate within infected amoebae. P. acanthamoebae has been found in humans with multiple respiratory infections such as pneumonia and bronchitis, indicating an association of the presence of this bacterium with severe disease. Transmission may also occur zoonotically through contact with contaminated animals. The understanding of potential complications of pregnancy associated with P. acanthamoebae infection is not understood, but there may be an association with infertility or recurrent miscarriage. Identification and diagnosis can be performed by co-culture of respiratory samples with amoebae or by quantitative PCR using primers specific to P. acanthamoebae . This bacterium is found around the world, but due to the lack of testing in patients, the incidence of infection is largely unknown.