Louisiana Research Day Program Book 2025

Case Studies: Section 1

Wasifuddin Syed, OMS-III 1 ; Kareem Abdelhamid, OMS-III 2 ; Hassan Khanani, OMS-III 3 ; Abir Islam, OMS-III 4 1 VCOM-Louisiana; 2 Department of Internal Medicine, Division of Pulmonary and Critical Care, Willis-Knighton Health, Shreveport, LA 100 ATYPICAL PRESENTATION OF SPORADIC LYMPHANGIOLEIOMYOMATOSIS IN A POSTMENOPAUSAL FEMALE WITH LONG TERM EXOGENOUS ESTROGEN EXPOSURE

Background: This case highlights an atypical presentation of sporadic

pulmonary function tests (PFTs) revealing an obstructive lung pattern (with reversible airflow obstruction in a third of cases), and elevated serum vesicular endothelial growth factor-D (VEGF-D). Diagnostic VEGF-D levels above 800 pg/mL, combined with characteristic imaging, confirm LAM. A 65-year-old Caucasian female with a history of hysterectomy, inflammatory bowel disease, 30-pack-year smoking history, and 25 years of transdermal estrogen therapy underwent pulmonology evaluation after incidental discovery of cystic lung disease. Patient denied symptoms but recalled past exertional dyspnea. HRCT revealed diffuse, thin-walled cysts, raising suspicion for LAM. PFTs showed moderate airflow obstruction, a 16% improvement in Forced Expiratory Flow (FEF) post-bronchodilator, and reduced diffusion capacity, consistent with LAM. Abdominal and pelvic CT revealed no renal findings indicative of TSC but identified pelvic lymphadenopathy, an extrapulmonary feature of LAM. Serum VEGF-D testing was considered for confirmation. A 3-month follow-up was planned for repeat imaging and PFTs. If progression or symptoms occur, treatment with sirolimus, an mTOR inhibitor, may be initiated. This case

underscores the importance of recognizing atypical presentations of LAM, particularly in asymptomatic postmenopausal patients. The patient’s age and lack of symptoms posed diagnostic challenges. HRCT and clinical evaluation prompted a differential diagnosis including LAM, lymphoid interstitial pneumonia, Birt-Hogg-Dubé syndrome, and Pulmonary Langerhans Cell Histiocytosis, which were systematically excluded through history, examination, and imaging. Narrowing the diagnosis to LAM highlights estrogen’s critical role in its pathogenesis. Estrogen promotes smooth muscle-like cell proliferation via mTOR signaling and enhances lymphangiogenesis, contributing to disease progression and lymphatic involvement, as observed in this patient. While endogenous estrogen’s role in LAM is well-documented, the impact of long-term exogenous estrogen merits further study. HRCT, VEGF-D levels, and PFTs are vital in diagnosing LAM. This case expands the understanding of LAM, encouraging consideration of its diagnosis in diverse populations and prompting further research into exogenous estrogen’s impact.

lymphangioleiomyomatosis (LAM) in a 65-year old postmenopausal female, a demographic rarely linked to this condition. LAM is a rare cystic lung disease characterized by abnormal growth of smooth muscle-like cells, primarily affecting the lungs and lymphatics, with an incidence of three to eight cases per million. LAM predominantly affects women of childbearing age and manifests in two forms: one associated with tuberous sclerosis complex (TSC) and sporadic LAM. TSC is an autosomal dominant disorder caused by mutations in the TSC1 or TSC2 gene, leading to neurocutaneous findings, cortical tubers, and facial angiofibromas; approximately 40% of these patients develop LAM. Sporadic LAM arises from somatic mutation without TSC features. Common symptoms include dyspnea on exertion, fatigue, chest pain, or cough. Patients with LAM have higher risk of recurrent pneumothorax and chylous effusions. Renal angiomyolipoma, seen in 30% of LAM cases, is more common with TSC-LAM. Diagnosis typically involves High-resolution CT (HRCT) showing diffuse thin-walled cysts,

Case Studies: Section 2

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115 2025 Research Recognition Day