Venous thromboembolism during mycoplasma pneumoniae infection: case report and review of the literature.

Mycoplasma pneumoniae infection is frequent but generally mild or self-limiting. Approximately 10% of cases develop clinical signs of pneumonia with "atypical" radiographic pattern. However, mycoplasma pneumoniae can be responsible for a variety of extrapulmonary manifestations, potentially involving all systems and apparatuses. Although exact pathophysiological mechanisms are not completely known, these could be secondary to direct invasion of the target organ, immunological damage due to molecular mimicry or vascular obstruction. A 45-year-old man was admitted to Internal Medicine Unit because of fever, dry cough and fatigue lasting 15 days. Fever disappeared after starting clarithromycin. About 72 h after admission the patient complained of right calf pain and tachypnea. The presence of anti-mycoplasma antibodies suggested mycoplasma pneumoniae infection. Moreover, a diagnosis of venous thrombo-embolism was performed. Given the absence of classical risk factors for thrombosis, patient was investigated for inherited and acquired thrombophilia and tested positive for antiphospholipid antibodies. A review of the English literature on the association between m. pneumoniae and pulmonary embolism will be provided in order to underline the possible pathogenetic role of antiphospholipid antibodies in this setting. Clinicians should outweigh risk and benefits for LMWH prophylaxis case by case considering these adjunctive pro-thrombotic mechanisms in patients m. pneumoniae infection.