OLD WOUNDS RUN DEEP: A CASE OF THORACIC SPLENOSIS FOLLOWING REMOTE TRAUMA

Abstract

TOPIC: Disorders of the Pleura TYPE: Medical Student/Resident Case Reports INTRODUCTION: Thoracic splenosis develops as a result of auto-transplantation of splenic tissue into the thoracic cavity following splenic and diaphragmatic injury. Less than 40 cases have been reported in the literature so far and it remains an elusive diagnosis.[1] The majority of cases were asymptomatic and presented as incidental findings on imaging. Few cases reported symptoms like pleuritic chest pain, hemoptysis, and phrenic nerve irritation that prompted a diagnostic workup. [2] We report one such case in which a young female with penetrating abdominal trauma and unexplained shortness of breath was diagnosed with thoracic splenosis. CASE PRESENTATION: Our patient is a 32-year-old female who presented for evaluation of lung nodules found on work-up for recurrent dyspnea. She had previously been treated for suspected bronchitis, however, complained of persistent exertional dyspnea, orthopnea, and fatigue. She denied any chest pain, fever, chills, cough, pedal edema, or weight loss. She had a history of a gunshot to the abdomen that resulted in splenectomy 8 years prior to presentation. Physical exam was unremarkable and bloodwork was normal. Chest x-ray showed pleural irregularities computed tomography revealed nodularity of the left pleural space. PET-CT revealed faint uptake in this area. Transthoracic biopsy of the pleura yielded an acellular specimen. Thoracic splenosis was suspected, and liver and spleen imaging with single-photon emission computed tomography was performed after injecting 5.7 mCi Tc-99m sulfur colloid. The study showed multiple foci of uptake corresponding with underlying soft tissue nodules in the left lower pleura, left lower chest wall, and bilateral mesentery. A diagnosis of thoracic splenosis secondary to penetrating trauma was made. The patient's spirometry was normal and she was managed with supportive care and reassurance. DISCUSSION: The diagnosis of thoracic splenosis can be challenging as there can be a significant lag between thoracoabdominal trauma and chest findings. The Tc-99 m heat-damaged erythrocyte scan has high sensitivity and specificity for splenic tissue, while Tc-99m sulfur colloid and indium-111-labeled platelets are less sensitive alternatives. CT-guided biopsies and needle aspirations typically have a poor yield and increased risk of bleeding. [4,5] As splenic tissue is slow-growing, non-invasive, and mostly asymptomatic, appropriate management is observation and reassurance. Surgical removal carries a significant risk of morbidity and is only attempted in patients with severe, persistent symptoms or increasing size of the mass. [3] CONCLUSIONS: Thoracic splenosis can be diagnosed with a thorough history and appropriate imaging, but patients often undergo invasive procedures such as bronchoscopy or surgery in order to rule out a neoplasm. Pulmonologists should be aware of this rare entity in order to avoid unnecessary procedures REFERENCE #1: Ha YJ, Hong TH, Choi YS. Thoracic Splenosis after Splenic and Diaphragmatic Injury. Korean J Thorac Cardiovasc Surg. 2019;52(1):47-50. doi:10.5090/kjtcs.2019.52.1.47 REFERENCE #2: Le Bars F, Pascot R, Ricordel C, et al. Thoracic splenosis: Case report of a symptomatic case. Chin J Traumatol. 2020;23(3):185-186. doi:10.1016/j.cjtee.2020.05.003 REFERENCE #3: Matthews A, Chesser M, Mand J, Thomas A. A Growth Opportunity: Thoracic Splenosis. Am J Med. 2017;130(4):420-422. doi:10.1016/j.amjmed.2016.11.010 DISCLOSURES: No relevant relationships by Sukhmani Boparai, source=Web Response No relevant relationships by David Chambers, source=Web Response No relevant relationships by Deon Ford, source=Web Response No relevant relationships by Prathik Krishnan, source=Web Response No relevant relationships by Shreedhar Kulkarni, source=Web Response No relevant relationships by Jonathan Packer, source=Web Response