Thoracic splenosis mimicking a pleuropneumonia

RATIONALE Splenosis is the development of one or more heterotopic splenic tissue autoimplants following rupture of the spleen and remains mostly asymptomatic. PATIENT CONCERNS We report a case of a 50-year old post-traumatic splenectomized man admitted for a left side community acquired pneumonia resistant to antibiotics. DIAGNOSES The diagnosis of intrathoracic ectopic spleen was suspected because of the history of spleen trauma with diaphragm rupture and the absence of Howell-Jolly bodies. INTERVENTIONS Technetium (Tc)-m colloid scintigraphy SPECT, fused with CT scan showed an intense radionuclide uptake on hyper vascularized masses without any additional pathologic uptake and confirmed the diagnosis of thoracic splenosis. OUTCOMES Despite any lifelong penicillin prophylaxis, he had no history of infections eight years after the diagnosis. LESSONS Physician must be aware of this differential diagnosis and of its consequences. Depending on its size and location, it may lead to incorrect diagnosis (tumor, empyema, abscess ...), treatment and invasive procedures while the diagnosis of splenosis only relies upon imaging studies associated with functionnal study of the uptake of particles or cells.