Gamna–Favre bodies

Gamna–Favre Bodies

Gamna–Favre bodies are intracellular inclusions that are typically found in the cytoplasm of cells infected with certain types of Chlamydia trachomatis. These inclusions are named after the Italian pathologist Carlo Gamna and the French physician Maurice Favre, who first described them in the context of lymphogranuloma venereum (LGV), a sexually transmitted infection caused by specific serovars of Chlamydia trachomatis.

Pathophysiology

Gamna–Favre bodies are formed as a result of the intracellular life cycle of Chlamydia trachomatis. This bacterium is an obligate intracellular pathogen, meaning it can only replicate within the host cell. During infection, Chlamydia trachomatis enters the host cell and forms a specialized vacuole known as an inclusion. Within this inclusion, the bacteria replicate and eventually form reticulate bodies, which are the replicative form of the bacterium.

As the infection progresses, the reticulate bodies transform into elementary bodies, which are the infectious form of the bacterium. The accumulation of these bodies within the host cell cytoplasm leads to the formation of Gamna–Favre bodies. These inclusions are typically seen in the epithelial cells of the genital tract in cases of lymphogranuloma venereum.

Clinical Significance

The presence of Gamna–Favre bodies is a histopathological hallmark of lymphogranuloma venereum, a condition characterized by the formation of genital ulcers, lymphadenopathy, and proctitis. LGV is more prevalent in tropical and subtropical regions but has been increasingly reported in other parts of the world, particularly among men who have sex with men (MSM).

Diagnosis of LGV can be supported by the identification of Gamna–Favre bodies in tissue samples, although modern diagnostic techniques such as nucleic acid amplification tests (NAATs) are more commonly used for definitive diagnosis.

Histological Appearance

Under the microscope, Gamna–Favre bodies appear as basophilic (blue-staining) inclusions within the cytoplasm of infected cells. They are often surrounded by a clear halo and can vary in size. These inclusions are best visualized using special staining techniques, such as Giemsa or immunohistochemical stains, which highlight the presence of Chlamydia antigens.

Treatment

The treatment of infections associated with Gamna–Favre bodies, such as lymphogranuloma venereum, typically involves the use of antibiotics. Doxycycline is the drug of choice, administered for a period of 21 days. Alternative treatments include azithromycin or erythromycin, particularly in cases where doxycycline is contraindicated.

Also see

• Lymphogranuloma venereum
• Chlamydia trachomatis
• Sexually transmitted infections
• Histopathology