Hilar lymphadenopathy associated with Chlamydia pneumoniae infection.

A 27-year-old man with an acute Chlamydia pneumoniae infection and hilar lymph node involvement is reported. Further investigation gave no evidence of sarcoidosis or other known cause of enlarged hilar nodes. Serological tests proved an acute infection with C. pneumoniae Thus, an infection with C. pneumoniae may lead to enlargement of the hilar lymph nodes, and infection with this microorganism should be included in the differential diagnostic considerations in patients with hilar lymphadenopathy.