SAT-354 Graves' Disease with Spontaneous Pneumothorax: A Rare Occurrence

Abstract Disclosure: S. Azmat: None. O. Lodhi: None. W. Akhter: None. A. Ahmed: None. R. Akhter: None. V. Trendafilova: None. Background: Grave's disease is an autoimmune syndrome characterized by hyperthyroidism, goiter, pretibial myxedema, and orbitopathy. The coexistence of Grave's disease with spontaneous pneumothorax is a rare occurrence as very few cases have been reported. One possible contributing mechanism includes the hypermetabolic status of Graves disease causing lung parenchymal fragility and predisposition for the formation/rupture of pulmonary blebs leading to spontaneous pneumothorax. We present a case of a young navy recruit who was brought to the emergency department and found to have spontaneous pneumothorax/pneumomediastinum with underlying Graves Disease.Clinical Case: A 20-year-old lean Hispanic male with BMI of 18 came with chief complaint of left-sided chest pain and palpitations. He denied having any other discomfort including dyspnea, diaphoresis, significant weight loss, or hot flashes. On arrival, he was dehydrated and tachycardic to 150bpm. Labs were significant for suppressed TSH (<0.008 μIU/mL)(0.27 4.2uIU/mL), elevated free T3 (7.7pg/mL)(2.3 4.1pg/mL) and free T4 (20ng/dL)(0.9 1.7ng/dL). Chest CT showed a small left apical pneumothorax (9mm), extensive pneumomediastinum, and subcutaneous emphysema with no esophageal or tracheal injury. As for the absence of pulmonary blebs or bullae, this could not be established because no prior CT imaging was available. Thyroid stimulating immunoglobulin (TSI) antibodies were positive, suggestive of Grave's disease. Thyroid ultrasound showed a hyperemic and diffusely heterogeneous thyroid gland, consistent with thyroiditis. Pt was started on propylthiouracil and propranolol with significant improvement in palpitations. Oxygen supplementation was given and pneumothorax and pneumomediastinum resolved spontaneously within 48 hours. He was discharged after stabilization. At two-week follow-up, the patient reported a complete resolution of his presenting symptoms. Labs showed improved thyroid function tests (TSH: 0.008 μIU/mL( 0.27-4.2 uIU/mL), free T3 4.51 pg/mL (2.3-4.1), free T4 1.24 ng/dL(0.9-1.7 ng/dL). He denied any side effects of therapy or recurrence of symptoms. The patient was advised to continue methimazole and propranolol therapy and follow up in six months. Conclusion: We hypothesize that our patient may have had a pulmonary bleb in the setting of his thin physique which could be due to Grave's Disease. Perhaps the underlying metabolic derangements predisposed him to develop focal pulmonary parenchymal abnormalities. He was a recruit and physical exertion at the military base may have led to bleb rupture. Our case highlights the importance of detailed multisystemic evaluation to reveal coexisting thyroid dysfunction and acute chest abnormalities. More studies are required to elucidate pathogenesis and association, to improve patient care. Presentation: Saturday, July 12, 2025