Gemella Morbillorum Associated Mediastinitis following EUS-FNA of a Posterior Mediastinal Lymph Node

Background: Only a few reports of mediastinitis after EUS-FNA of mediastinal reports have been reported in the literature. We present the first reported case of Gemella morbillorum mediastinitis following EUS-FNA of a posterior mediastinal lymph node (LN). Methods: Case report using retrospective review of medical records. Results: A 78-year-old man with a history of a T3N0M0 adenocarcinoma of the colon removed four years earlier underwent routine surveillance PET scan and was found to have intense activity corresponding to a 1cm diameter aorto-pulmonary window LN which was suspicious for malignancy. The patient had a history of non-insulin dependent diabetes and hypertension. Trans-esophageal EUS-FNA (5 passes, 22G needle) of the LN revealed benign lymphoid tissue. No antibiotic prophylaxis was given. 5 days later, he presented with retrosternal chest pain, fever, chills and leukocytosis. A chest CT scan demonstrated inflammatory changes consistent with mediastinitis adjacent to the enlarged lymph node which had undergone EUS-FNA. Blood cultures grew Gamella morbillorum which was sensitive to penicillin and ceftriaxone. The patient was treated with ceftriaxone and metronidazole. Clinical symptoms resolved, and blood cultures were negative. A follow-up CT scan, 2 weeks post-discharge, revealed persistent posterior mediastinal inflammation with spondylitis and diskitis at the T6-T7 level. Conclusions: 1) Mediastinitis can occur after trans-esophageal EUS/FNA of posterior mediastinal lymph nodes. 2) Gemella morbillorum should be considered in the list of bacteria that may be associated with infective complications following EUS-FNA. 3) Endosonographers should keep a high index of suspicion for infection following EUS/FNA of mediastinal lymph nodes, and not only cystic lesions. 4) Prophylactic antibiotics may be considered in selected patients undergoing trans-esophageal EUS/FNA.