Follow-up Chest CT Research Articles

Second, Peculiar Recurrence of a Wilms Tumor - Pleural And Late

Nephroblastoma (Wilms tumour) is the most common kidney malignancy in children and one of the most frequent abdominal tumours diagnosed in pediatric patients. We present the case of a 2-year-old boy diagnosed with intermediate-risk, regressive-type nephroblastoma of the left kidney in 2010. He was treated with neoadjuvant chemotherapy followed by surgery and chemotherapy (following the International Society of Pediatric Oncology- SIOP protocol). After 11 months a metastasis was discovered in the left lungand the patient was (re)classified as being high risk and treated with seven cyclesof chemotherapy. After nine disease-free years, the routine follow-up chest CT scan showed a 10/5cm tumor in the left lung involving the pleura. The tumor was completely resected, and pathology confirmed a distal recurrence of nephroblastoma. The patient was further treated according to the UMBRELLA protocol (BB group) with chemotherapy and local irradiation. The tumor bed was irradiated with 25.2 Gy/14 fr, using Helical Tomotherapy. Following radiotherapy, hereceived a high dose chemotherapy and autollogus stem-cell transplant, with a good response and without disease recurrence.

PSAT340 Thymic Hyperplasia in Graves’ Disease: A Case Report

Abstract Background Thymic hyperplasia (TH) can occur in Graves’ disease (GD) due to direct effect of thyroid hormone or thyrotropin receptor antibody stimulation. Recognition of this entity is important as treatment of GD can lead to reduction in TH and can prevent unnecessary intervention. This case highlights thymus enlargement likely due to TH in the setting of GD. Case A 44-year-old female with history of left-sided invasive breast cancer status post partial mastectomy and radiation therapy, was found to have an anterior mediastinal mass on surveillance breast MRI. Follow-up chest CT and MRI showed a homogenous anterior mediastinal mass (4.7×2.4×12.6 cm) and thyromegaly. She had a prior history of Hashimoto's thyroiditis diagnosed 20 years, not on treatment, as well as active tobacco use (0.5 PPD for 10 years). She had symptoms of weight loss, palpitations, heat intolerance and tremors. Physical examination revealed tachycardia, flushing, lid lag, diffusely enlarged thyroid and fine tremors. Laboratory investigation showed TSH < 0.01 uIU/mL (0.35-4.94 uIU/mL), free T4 2.84 ng/dL (0.5-1.39 ng/dL), total T3 479 ng/dL (48-178 ng/dL), positive TPO, TSI and thyroglobulin antibodies confirming GD. She was initially treated with methimazole and propranolol with plans for thymectomy. Treatment was complicated by methimazole induced agranulocytosis with absolute neutrophil count of 114 cells/uL (1500-7800 cells/uL) requiring hospitalization. Methimazole was discontinued, and she was treated with antibiotics, propranolol, prednisone, cholestyramine and potassium iodide before undergoing total thyroidectomy. Pathology was consistent with GD with an incidental 2 mm papillary thyroid microcarcinoma. Post-operatively she was started on levothyroxine. Follow up CT chest two weeks after surgery showed a decrease in size of the mediastinal mass supporting a diagnosis of TH secondary to GD. She is planned for repeat imaging in several months to determine if thymectomy is indicated. Discussion TH can occur in GD secondary to direct trophic effect from excess thyroid hormones or thyrotropin receptor antibody stimulation. Prevalence is unknown; however, studies have shown that approximately one-third of patients with GD have histological evidence of TH. In most documented cases, thymic enlargement is minimal; a 2014 study found 107 documented cases of GD related thymus enlargement, of which only 4 were malignant. Since anterior mediastinal masses can have a high malignancy potential, it is warranted to thoroughly evaluate the radiographic characteristics for malignancy including heterogeneous enhancement, invasion to surrounding structures, and presence of calcification. However, in the presence of untreated hyperthyroidism and absence of suspicious radiographic features, tissue biopsy or thymectomy should be avoided due to high risk of complications such as thyroid storm. TH in GD is often reversible with treatment of GD. Follow up chest imaging to look for decrease in size of thymus is recommended to reevaluate future need for biopsy or thymectomy. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

CORRELATING MALIGNANCY RISK FROM AN ARTIFICIAL INTELLIGENCE (AI) ALGORITHM AND LUNG-RADS-BASED CLASSIFICATION FROM SCREENING LOW-DOSE CT IMAGING

CORRELATING MALIGNANCY RISK FROM AN ARTIFICIAL INTELLIGENCE (AI) ALGORITHM AND LUNG-RADS-BASED CLASSIFICATION FROM SCREENING LOW-DOSE CT IMAGING

LUNG CAVITY: A RARE FINDING IN COVID-19

LUNG CAVITY: A RARE FINDING IN COVID-19

Evaluation of lactate dehydrogenase (LDH) in predicting the severity of lung involvement and pneumomediastinum in hospitalized COVID-19

BackgroundCOVID-19 is a health crisis that triggered the need to find a rapid and sensitive tool to screen populations with a high risk of complications. Lactate dehydrogenase (LDH) is an enzyme found in almost all body cells, particularly pneumocytes, and appears to be associated with worst outcome. Pneumomediastinum (PM), which results from ruptured alveoli, can occur in non-ventilated patients. Acute pneumocytes injury induces the release of serum LDH. ObjectiveThis study evaluates the role of baseline serum LDH levels in predicting COVID-19 lung necrosis. MethodsThis retrospective study was conducted among 524 COVID-19 patients admitted to Hôtel-Dieu de France university hospital, Lebanon, between March 2020 and March 2021. Baseline serum LDH was retrieved from patients’ medical records. Radiological severity outcomes were assessed at admission and during follow-up by non-contrast computed tomography (NCCT) of the chest. ResultsThe mean age of participants was 63 ± 16 years, with 359 males (68.5%) and median (IQR) LDH levels upon admission of 328 (248–430). LDH was correlated with lobar involvement at both admission and NCCT follow-up (Spearman’s rho 0.527 and 0.264, respectively) and the development of a PM (p = 0.035) in 3% of the patients. Using ROC analysis, a baseline LDH value higher than 395 U/L was associated with the presence of a PM on admission and follow-up chest CT, with a sensitivity of 75% and a specificity of 60.1%. ConclusionBaseline LDH levels could serve as a tool for early diagnosis of severe pulmonary injury with poor radiological outcomes in hospitalized COVID-19 patients.

Abstract 4120: Acquired TPM3-NTRK1 fusion resistant to larotrectinib in a non-small cell lung cancer with EML4-ALK fusion progressed on lorlatinib

Abstract Background: As oncogenic driver genes have been detected, targeted therapy plays a crucial role in non-small cell lung cancer (NSCLC) with targeted mutation. Lorlatinib, a selective third-generation inhibitor of anaplastic lymphoma kinase (ALK), is a treatment option for ALK-positive NSCLC patients who previously failed on ALK tyrosine kinase inhibitors (TKIs). Larotrectinib, a highly selective tropomyosin receptor kinase (TRK) inhibitor, is a treatment option for NSCLC with neurotrophic tyrosine receptor kinase (NTRK) mutation. Herein, we present an acquired TPM3-NTRK1 fusion resistant to larotrectinib in lung adenocarcinoma with EML4-ALK fusion progressed on lorlatinib. Case Presentation: A 48-year-old male with stage IV adenocarcinoma of lung with metastatic disease of bone was initially treated with carboplatin, pemetrexed, and pembrolizumab. Follow up CT in 4 months showed numerous hepatic lesions and liver biopsy demonstrated large cell neuroendocrine carcinoma. Upon progression of disease (PD), systemic therapy regimen was switched to combination of carboplatin, paclitaxel, and bevacizumab. After two months since starting the new regimen, a second PD was observed. Follow-up MRI brain demonstrated multiple small metastatic lesions. Subsequently, he was started on alectinib 600 mg twice a day given EML 4-ALK fusion mutation [4.8% of variant allele frequency (VAF)] in circulating tumor DNA (ctDNA) NGS assay. Follow-up CT chest in 5 months showed 5 mm left lower lobe nodule which remained unchanged in size. He maintained SD for 9 months before repeat MRI brain demonstrated PD with new leptomeningeal carcinomatosis. Subsequently, he received whole brain radiotherapy and the treatment regimen was switched to lorlatinib 100 mg daily. In 7-week follow-up CT, the 5 mm nodule in the left lower lobe was stable. Follow-up MRI brain in 16 weeks showed decrease in size and number of numerous enhancing parenchymal and leptomeningeal lesions. Overall SD was maintained for 8 months before follow-up MRI brain showed new punctate lesions. Repeat ctDNA NGS assay revealed new TPM3-NTRK1 fusion (VAF 0.2%) and ALK L1196M (VAF 2.8%), and a decision was made to add larotrectinib 100 mg daily. The 6-week follow-up MRI brain showed new parenchymal brain metastases. Discussion: It has been reported that the development of ALK resistance mutations may be associated with specific EML4-ALK variants. However, the influence of the specific EML4-ALK variants in NSCLC was not fully investigated. We report the case of acquired TPM3-NTRK1 fusion resistant to larotrectinib and acquired ALK L1196M in lung adenocarcinoma with EML4-ALK fusion progressed on lorlatinib. Further investigations are warranted to explore the mechanism of resistance to ALK TKIs. Citation Format: Horyun Choi, Jinah Kim, Yeun Ho Lee, Leeseul Kim, Na Hyun Kim, Young Kwang Chae. Acquired TPM3-NTRK1 fusion resistant to larotrectinib in a non-small cell lung cancer with EML4-ALK fusion progressed on lorlatinib [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4120.

A CASE REPORT OF COMPLICATIONS IN A SURVIVOR OF SEVERE COVID-19: PULMONARY FIBROSIS AND LONG-TERM SUPPLEMENTAL OXYGEN REQUIREMENT

TYPE: Case Report TOPIC: Diffuse Lung Disease INTRODUCTION: COVID 19 has caused about 4.5 million deaths worldwide and still counting. More than 50% of survivors develop post covid respiratory symptoms. we are presenting a case report of severe COVID 19 survivor with diffuse pulmonary fibrosis after longterm follow up. CASE PRESENTATION: 75 year old male with BMI 38, history of hypertension, CAD, CKD, diabetes presented with shortness of breath. Further testing came back COVID 19 and influenza B positive, CT chest showing bilateral diffuse ground glass opacities and infiltrates consistent with COVID 19 pneumonia. He was given empiric antibiotics, IV steroids, plasma therapy and supportive care with NIV, weaned down to vapotherm 40 L, 100%fio2. He didn’t undergo mechanical ventilation, has been in hospital for 50 days and was discharged on 5L oxygen. After 8 months, he was readmitted to hospital for pneumonia requiring 7 L supplemental oxygen, followup CT chest showing diffuse bilateral pulmonary fibrosis which was not present on initial CT. Upon discharge he continued to require 5l supplemental oxygen with no significant symptoms after 1 month follow up. DISCUSSION: In our case obesity, obstructive sleep apnea, uncontrolled hypertension, coexisting infection with influenza are likely risk factors for prolonged oxygen requirement and pulmonary fibrosis. Cytokine storm in severe covid could be a triggering factor. Chronic post covid 19 symptoms beyond 12 weeks should get further evaluation by pulmonary function tests, high resolution CT to asses severity. CONCLUSIONS: Close followup and early intervention can decrease mortality. The role of antifibrotic drugs, long-term steroid therapy, chest physical therapy need to be evaluated. DISCLOSURE: Nothing to declare. KEYWORD: post covid, pulmonary fibrosis, long term oxygen

Analysis of the interactions between small pulmonary nodules, clinical factors and the risk of malignancy in the chest following diagnosis of head and neck cancer.

This study aims to investigate radiological and clinical factors which predict malignancy in indeterminate pulmonary nodules in patients with head and neck cancer (HNC). Prospective data were collected in 424 patients who were reviewed in the NHS Lothian HNC multidisciplinary meeting from May 2016 to May 2018. Staging and follow-up CT chest imaging were reviewed to identify and assess pulmonary nodules in all patients. About 61.8% of patients had at least one pulmonary nodule at staging CT. In total, 25 patients developed malignancy in the chest. Metastatic disease in the chest was significantly associated with unknown or negative p16status (p<.0005). Pleural indentation and spiculation were associated with indeterminate nodules, subsequently being shown to represent metastatic disease (p>.0005 and p=.046, respectively). Negative or unknown p16status was associated with an increased propensity to develop metastatic disease in the chest in patients with HNC.

Microwave ablation via a flexible catheter for the treatment of nonsurgical peripheral lung cancer: A pilot study.

BackgroundEndobronchial microwave ablation via flexible catheter offers the potential for local therapy for inoperable peripheral lung cancer. The study aimed to evaluate the feasibility and safety of navigation bronchoscopy‐guided water‐cooled microwave ablation catheter for nonsurgical peripheral lung cancer.MethodsThis was a prospective single arm pilot study. Patients with early stage or multiple primary peripheral lung cancer who were nonsurgical candidates for surgery were enrolled in the study. Bronchoscopic microwave ablation was performed via a flexible water‐cooled microwave ablation antenna under the guidance of navigation bronchoscopy. Radial probe endobronchial ultrasound combined with fluoroscopy was used to confirm the position. Treatment outcomes were evaluated based on follow‐up chest CT and positron emission tomography scans. Primary endpoints were technical success and safety. Secondary endpoints were complete ablation rate, 2‐year local control rate, and progression‐free survival.ResultsThirteen patients were enrolled in the study from April 2018 to July 2019. A total of 19 sessions of microwave ablation were performed on 14 tumors under the guidance of navigation bronchoscopy. The technical success was 100%. Treatment‐related complications occurred in two patients. The complete ablation rate was 78.6% (11/14). The 2‐year local control rate was 71.4%. Median progression‐free survival was 33 months for all patients.ConclusionsIn this pilot study, bronchoscopic microwave ablation appears to be feasible with acceptable occurrence of complication in the treatment of peripheral lung cancer under the guidance of navigation bronchoscopy.

February 2022 Medical Image of the Month: Multifocal Micronodular Pneumocyte Hyperplasia in the Setting of Tuberous Sclerosis

No abstract available. Article truncated at 150 words. A 22-year-old man with a known diagnosis of Tuberous Sclerosis Complex (TSC) presents for a follow-up unenhanced chest CT to re-evaluate pulmonary nodules seen in the lung bases on a prior abdominal CT. The patient also has a history of multiple renal lesions consistent with lipid-poor angiomyolipomas based on previous abdominal MRI findings. The chest CT demonstrated multiple scattered, randomly distributed sub-centimeter pulmonary nodules of solid or subsolid morphology [Figure 1A]. Those nodules visible in the lung bases on the prior abdominal CT had remined stable over the 12-month interval consistent with multifocal microscopic pneumocyte hyperplasia (MMPH)[Figure 1B,C]. Myocardial fatty foci (MFF) were visualized in the heart on soft tissue window display settings [Figure 2A] as were multiple scattered sclerotic bone lesions on bone window display settings [Figure 2B,C]. No pulmonary cysts were seen to suggest lymphangioleiomyomatosis (LAM) and there were no thoracic lymphangiomas. MMPH represents a benign hamartomatous proliferation …

POS-760 PULMONARY ANGIOINVASIVE ASPERGILLOSIS IN A KIDNEY RECIPIENT: AN ATYPICAL CLINICAL PRESENTATION

Angioinvasive aspergillosis is a rare opportunistic infection. its occurrence increases the mortality and morbidity of organ transplant recipients. It is about a 27-year-old patient with a history of end-stage renal failure due to an apparent mineralocorticoid deficiency, hemodialysis for 10 months until he received a kidney transplant from a related living donor sharing 4 HLA identities. He received induction therapy with globulin antithymocyte and methylprednisolone followed by maintenance therapy with Mycophenolate Mofetil, prednisolone, tacrolimus. Since the recipient was not immune to cytomegalovirus (CMV), he received ganciclovir prophylaxis immediately after transplant. Post-transplant evolution was marked by the immediate resumption of diuresis, creatinine figures stagnating between 200 and 250 µmol/l. The remainder of her usual treatment consists of a proton pump inhibitor, β-blocker, cotrimoxazole. Our patient presented 2 months post transplant with febrile neutropenia. Clinically, apart from a fever of 38 °, the examination was without abnormalities. Biologically, pancytopenia, inflammatory syndrome (high CRP and procalcitonin), hypokalaemia, hypophosphatemia and hypomagnesemia, hyperferritinemia and hypertriglyceridemia were noted. A post-infectious macrophagic activation syndrome was suspected, confirmed by a sternal puncture. An etiological investigation has been launched ; viral serologies (HBV, HCV, HIV, EBV, CMV, COVID 19, HSV) were negative, a cardiac ultrasound ruled out infective endocarditis, a thoracoabdominal CT scan showed multifocal sub-segmental parenchymal condensations of the right lung surrounded by a halo, an appearance suggesting angio-invasive pulmonary aspergillosis and intracortical graft hematomas. Sputum bacteriological examination did not show pneumocystis but isolated two types of candida crucei and tropicalis. A weakly positive aspergillus antigenemia (index : 0.53) was noticed. Our patient received triple antibiotic therapy (vancomycin / imipenem / levofloxacin) and an antifungal (voriconazole) after adaptation according to the antibiogram for a total duration of 15 days with daily dosage of tacrolimus. In addition, he received venoglobulins for 5 days at a dose of (0.4 mg / kg / day). The clinical and biological course was favorable with apyrexia and improvement in the blood count from the third day of treatment. Aspergillus antigenemia and a follow-up chest CT scan were scheduled after the end of treatment. Initially, In view of the intensity of the induction treatment received, leuconeutropenia and in order of frequency, the 2 most evoked causes were CMV et covid19 but the CT aspect straightened the diagnosis, which was supported by aspergillary antigenemia. The emerging interest of this case report is the clinical and computed tomography discordance and the unusual rapidly favorable outcome to an aspect of angioinvasive pulmonary aspergillosis which usually show respiratory signs such as cough, hemoptysis or even respiratory distress. Invasive mycoses, associated with significant morbidity and mortality, are a frequent difficulty in solid organ transplantation. The clinical pictures differ and we could be faced with an atypical presentation which affects the therapeutic management.

Uniportal thoracoscopic decortication for stage Ⅲ tuberculous empyema of 158 cases

Objective: To examine the safety and feasibility of uniportal video-assisted thoracoscopic (VATS) decortication in patients presenting with stage Ⅲ tuberculous empyema. Methods: From August 2017 to July 2020, 158 patients of stage Ⅲ tuberculous empyema underwent uniportal VATS decortication with partial rib resection and customized periosteal stripper in Department of Thoracic Surgery, Shanghai Pulmonary Hospital. There were 127 males and 31 females, aged (M(IQR)) 32(28) years (range:14 to 78 years). Follow-up was performed in the outpatient clinic or via social communication applications, at monthly thereafter. If there was no air leak and chest tube drainage was less than 50 ml/day, a chest CT was performed. If the lung was fully re-expanded, chest tubes were removed. All patients received a follow-up chest CT 3 to 6 months following their initial operations which was compared to their preoperative imaging. Results: There was one conversion to open thoracotomy. The operative time was 2.75 (2.50) hours (range: 1.5 to 7.0 hours), and median blood loss was 100 (500) ml (range: 50 to 2 000 ml). There were no perioperative mortalities. There were no major complications except 1 case of redo-VATS for hemostasis due to excessive drainage and 1 case of incision infection, The incidence of prolonged air leaks (>5 days) was 80.3%(126/157). The postoperative hospital stay was 5.00 (2.25) days (range: 2 to 15 days). All patients were discharged with 2 chest tubes, and the median duration drainage was 21.00 (22.50) days (range: 3 to 77 days). Follow-up was completed in all patients over a duration of 20 (14) months (range: 12 to 44 months). At follow-up, 149 patients(94.9%) recovered to grade Ⅰ level, 7 patients to grade Ⅱ level, and 1 patient to grade Ⅲ level. Conclusion: Uniportal VATS decortication involving partial rib resection and a customized periosteal stripper is safe and effective for patients with stage Ⅲ tuberculous empyema.

INCIDENTAL FINDING OF PULMONARY MUCOSA-ASSOCIATED LYMPHOID TISSUE LYMPHOMA

TOPIC: Lung Cancer TYPE: Medical Student/Resident Case Reports INTRODUCTION: Primary pulmonary lymphomas (PPLs) comprise 1% of lung neoplasias, with pulmonary mucosa associated lymphoid tissue (MALT) lymphoma making up approximately 80% of these lesions. Pulmonary MALT lymphoma is a rare extranodal marginal zone B-cell lymphoma that is typically indolent in nature. Clinical manifestations of pulmonary MALT include fever, malaise, cough, dyspnea, and chest pain, although 30% of patients can be asymptomatic. We present a case of an incidental discovery and diagnosis of pulmonary MALT lymphoma. CASE PRESENTATION: 72-year-old male lifelong non-smoker with medical history of hypertension presented to pulmonology clinic due to incidental central left lower and perihilar ground glass density seen on CT performed for coronary calcium scoring. He denied symptoms, and his physical examination and laboratory values were normal. Follow-up CT chest with contrast showed a persistent 3.5 cm ground-glass lesion in the superior segment of the left lower lobe. Navigational bronchoscopy with biopsy and bronchoalveolar lavage was performed. The pathology revealed bronchial mucosa with a dense atypical lymphoid infiltrate and predominance of CD20 positive and CD5 negative B lymphocytes. These findings were consistent with a lymphoproliferative disorder of MALT lymphoma. FDG PET-CT demonstrated moderate uptake in the left lower lobe nodule with no other significant uptake elsewhere in the body. The patient was evaluated by medical oncology and is undergoing active surveillance with repeat CT anticipated in 3 months. DISCUSSION: Onset of PPL occurs around 50-60 years of age and the rate of smoking in these patients is not higher than that of the general population. Pulmonary MALT lymphoma is associated with chronic antigen stimulation, but unlike other MALT lymphomas, they have not yet been associated with chronic infection. They are often associated with cytogenetic abnormalities, 42% of cases having the translocation t(11;18)(q21;q21). Diagnosis is made by tissue biopsy, usually bronchoscopic versus CT guided. Pathology and immunohistochemistry are significant for lymphoid infiltrates expanding lymphoid follicle marginal zones with CD20 positive and CD5 negative cells. Treatment options include chemotherapy, radiation therapy, immunotherapy, surgical management, or an expectant approach in cases of limited disease. Overall five-year survival for patients is greater than 80%. CONCLUSIONS: The pathogenesis of pulmonary MALT lymphoma is not well understood. Due to its rare occurrence, there are limited studies of treatment of these lymphomas and therefore no true consensus regarding best treatment strategies. With slow growth rates, a watch and wait plan may be a suitable approach to isolated pulmonary lesions and has not been shown to negatively affect overall survival. However, a better understanding of the pathophysiology and optimal treatment of these lymphomas requires further studies. REFERENCE #1: Sanguedolce F, et al. Primary pulmonary B-cell lymphoma: A review and update. Cancers. 2021; 13(3): 415. REFERENCE #2: Borie R. Pulmonary mucosa-associated lymphoid tissue lymphoma revisited. Eur Respir J. 2016;47(4):1244-60 REFERENCE #3: Yan W. Watch-and-wait or immediate immunotherapy/immunochemotherapy in patients with phase IE primary pulmonary MALT lymphoma? A multicenter retrospective study. Annals of Hematology. 2021; 100(3): 709-714. DISCLOSURES: No relevant relationships by Nicole Bernskoetter, source=Web Response Speaker/Speaker's Bureau relationship with Astra Zeneca, GSK Please note: $1001 - $5000 by Daniel Gerardi, source=Web Response, value=Honoraria No relevant relationships by Simrina Sabharwal, source=Web Response

SIGNIFICANT DYSPNEA IN POST-ACUTE COVID-19 IS ASSOCIATED WITH ABNORMAL PULMONARY VASCULATURE ON CT DURING THE ACUTE PHASE

TOPIC: Chest Infections TYPE: Original Investigations PURPOSE: SARS-CoV-2 is a highly contagious respiratory virus associated with significant morbidity and mortality in the acute phase. It is also associated with long-term morbidity in a subset of patients. It is not clear which patients will have persistent symptoms. SARS-CoV-2 affects the pulmonary vasculature. We hypothesize that differences in blood volume measurements on CT of the chest during the acute phase are associated with significant dyspnea after the acute phase. METHODS: We retrospectively studied subjects hospitalized for COVID-19 pneumonia who had an initial and follow-up CT chest, pulmonary function tests (PFTs), 6-minute walk test (6MWT), and a clinical assessment in our post-COVID-19 clinic. We excluded subjects with pre-existing lung disease based on prior PFTs. Serum inflammatory biomarkers, CT scan, and clinical characteristics were assessed during the hospitalization. CT images were evaluated by Functional Respiratory Imaging (deep learning trained) with automated tissue segmentation algorithms of the lungs and pulmonary vasculature. Volumes of the pulmonary vessels that were ≤5mm2 (BV5), 5-10mm2 (BV5_10), and ≥10mm2 (BV10) in cross-sectional area were analyzed. Additionally, the amount of opacification on CT (i.e., ground-glass opacities, crazy paving, reticular disease and edema) was quantified in each patient. PFTs were performed <3 months after discharge. We defined a modified Medical Research Council (mMRC) score≥2 as having significant dyspnea. We compared subjects with an mMRC score≥2 to those with an mMRC score<2. BV measures were also compared to a historical cohort of healthy controls. RESULTS: 50 subjects were included. 22 had mMRC score≥2. The groups had similar baseline characteristics. Admission hemoglobin, peak inflammatory biomarkers, and follow-up PFTs were similar between groups. On 6MWT, there were no differences between groups in resting SpO2, lowest SpO2, or walk distance. On admission CT, percent BV5 was lower, and percents BV5_10 and BV10 were higher in the mMRC≥2 group compared to the mMRC<2 group. All BV measures in both groups were different compared to healthy controls. At follow-up, BV5 measures in the mMRC≥2 group improved but remained abnormal compared to healthy controls, without a statistical difference compared to the mMRC<2 group. Opacification was similar between groups on admission and follow-up CTs. CONCLUSIONS: Despite similar baseline characteristics, lung function, degree of opacification and oxygenation, persistent dyspnea after COVID-19 pneumonia is related to pruning of the small pulmonary vessels (BV5) during the acute phase and not to differences in vascular abnormalities seen in short term follow-up. CLINICAL IMPLICATIONS: Identification of markers of persistent dyspnea in post-acute COVID-19 contributes to a better understanding of the natural course and prognosis of the disease. This will impact research and patient care in the near future. DISCLOSURES: No relevant relationships by Melinda Darnell, source=Web Response Owner/Founder relationship with Fluidda Please note: $20001 - $100000 by Jan De Backer, source=Web Response, value=Ownership interest No relevant relationships by Derlis Fleitas Sosa, source=Web Response No relevant relationships by Victor Kim, source=Web Response Employee relationship with FLUIDDA Please note: 02/01/2017 - Present Added 04/26/2021 by Maarten Lanclus, source=Web Response, value=Salary No relevant relationships by Ifeoma Oriaku, source=Web Response No relevant relationships by Daniel Salerno, source=Web Response

IDIOPATHIC CHRONIC EOSINOPHILIC PNEUMONIA EVOLVING TO PULMONARY FIBROSIS: A RETROSPECTIVE ANALYSIS

TOPIC: Diffuse Lung Disease TYPE: Original Investigations PURPOSE: Some patients with idiopathic chronic eosinophilic pneumonia (ICEP) may develop pulmonary fibrosis. This study was conducted to investigate the predictors of fibrosis developing in patients with ICEP. METHODS: A retrospective, computer-assisted search was performed to identify patients with ICEP seen at Mayo Clinic, Rochester from 1997-2019. Those patients who had follow-up chest CT beyond 12 months after the ICEP diagnoses were included in the study. Demographics, clinical, radiologic, and histopathologic features were analyzed. Proportional hazards regression was used to assess the predictors of pulmonary fibrosis. RESULTS: We identified 68 patients; mean±SD age at the time of ICEP diagnosis was 56.4±13.2 years, 60% female. Cough (87%) followed by shortness of breath (84%) and wheezing (35%) were the most common presenting symptoms. 41% had history of smoking and 46% had history of asthma. During follow-up 29 patients (43%) developed CT evidence of pulmonary fibrosis; 76% of these patients had a CT pattern inconsistent with usual interstitial pneumonia (UIP) pattern. The CT evidence of pulmonary fibrosis developed within 2 years after the diagnosis of ICEP in the majority of these patients. Age, body mass index (BMI) and male sex were the predictors of pulmonary fibrosis. On the other hand, history of asthma decreased the likelihood of developing pulmonary fibrosis. CONCLUSIONS: Development of pulmonary fibrosis is not uncommon in patients with ICEP, especially in older males with high BMI, and is associated with an increased risk of mortality. CLINICAL IMPLICATIONS: The clinical implication of our study is to recognize this phenomenon and to keep following up patients with ICEP especially those with risk factors for pulmonary fibrosis. Early institution of prednisone should be considered. DISCLOSURES: No relevant relationships by Misbah Baqir, source=Web Response No relevant relationships by Tucker Johnson, source=Web Response No relevant relationships by Tobias Peikert, source=Web Response No relevant relationships by Jay Ryu, source=Web Response No relevant relationships by Darrell Schroeder, source=Web Response No relevant relationships by Joanne Yi, source=Web Response

S1549 An Ominous Connection Causing Recurrent Pleural Effusions

Introduction: Fistulation is a rare complication of chronic pancreatitis. Pancreaticopleural fistula (PPF) typically presents with thoracic symptoms. Pathogenesis is related to pancreatic duct obstruction causing leakage of pancreatic fluid, and if persistent can lead to fistula formation. Due to its predominant thoracic over abdominal symptoms, the diagnosis and treatment of PPF are usually delayed. The following case is an example of the potential need for repeat testing to confirm the diagnosis of PPF as well as a multidisciplinary approach to treatment. Case Description/Methods: A 66-year-old white woman presented to the emergency department with 10 days history of worsening dyspnea, orthopnea, and chest tightness. Her medical history was notable for alcohol-induced chronic pancreatitis. On physical examination, she was tachycardic with diminished breath sounds bilaterally. Chest CT angiogram revealed bilateral pleural effusions. Diagnostic right sided thoracentesis revealed exudative fluid pattern, but negative for infection and malignancy. Symptoms initially improved after therapeutic thoracentesis, but pleural effusions shortly recurred requiring repeat thoracenteses. Pleural effusions laboratory findings on thoracenteses are listed in Tables 1 and 2. MRCP showed an irregular tubular tract extending cephalad from the pancreas toward the right diaphragmatic crus and appeared to communicate with the right hydropneumothorax (Figure 1). ERCP was performed which showed diffuse dilatation of the pancreatic duct (Figure 2). Patient underwent therapeutic stenting to the ventral pancreatic duct (Figure 3). She had complete resolution of symptoms and pleural effusions on 2 months follow-up chest CT. Discussion: Pancreatic pleural fistula is a rare complication of chronic pancreatitis and can be a challenging diagnosis as symptoms tend to overlap with other causes of dyspnea, hypoxia and pleural effusions. MRCP is the most sensitive imaging modality, followed by ERCP and CT to visualize pancreatic duct anatomy and guide further therapeutic management. Conservative medical management with bowel rest and somatostatin analog are shown to be effective in patients without pancreatic ductal obstructions. In cases with recurrent pleural effusions despite conservative management, ERCP with therapeutic stenting to alleviate pancreatic ductal obstructions is strongly indicated with high success rate. Owing to its rarity and complexity, a multidisciplinary approach to PPF is warranted to provide the best care possible.Figure 1.: Tables and Figures.

A RARE CASE OF INTERSTITIAL LUNG DISEASE IN IDIOPATHIC INFLAMMATORY MYOSITIS ASSOCIATED WITH ANTI-MDA5

TOPIC: Pulmonary Manifestations of Systemic Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Anti-MDA5 (anti-melanoma differentiation-associated gene-5) associated dermatomyositis (DM) is a rare presentation of idiopathic inflammatory myositis, often presenting with treatment refractory rapidly progressing interstitial lung disease (ILD). Diagnosis is difficult as patients can present without symptoms or biochemical evidence of DM. We report a rare adult case of anti-MDA5 ILD with only pulmonary manifestations. CASE PRESENTATION: 74-year-old female with past medical history of atrial fibrillation status post pacemaker, reactive airway disease, and heart failure with preserved ejection fraction, was referred to pulmonary clinic for abnormal CT scan and dyspnea that began 4 months prior while living in India. Initial chest CT was significant for bi-apical consolidations and bronchiectasis. Bronchoscopy with lavage was positive for Aspergillus galactomannan, and she was treated with isavuconazole, prednisone, and Septra (for pneumocystis prophylaxis). Chest CT 4 weeks later showed improvement in consolidations. 3 months later, dyspnea recurred. She was re-started on prednisone 20 mg daily, and dyspnea resolved. She subsequently relocated to the USA. She had serial negative COVID tests. Pulmonary function test showed a restrictive ventilatory defect with decreased diffusion capacity. Follow-up CT chest revealed bi-apical scarring, and multifocal airspace consolidation. ESR 44 (elevated) and CRP 11.2 (elevated). IGE, aldolase, CK, hypersensitivity pneumonitis antibody panel, Aspergillus antibody, nuclear antibody panel, RF, and anti-CCP were negative. Extended myositis panel revealed high positive titer for anti-MDA5 and RNA polymerase 3 antibodies;subsequently confirmed with a different extended myositis assay. She was referred to a rheumatologist who recommended aggressive immune modulating treatment with prednisone, tacrolimus and cyclophosphamide. After discussion, she opted for mycophenolate mofetil and prednisone. DISCUSSION: Anti-MDA5 associated DM can present with rapidly progressive ILD and is associated with poor prognosis. In a small prospective study, a triple therapy regimen consisting of high dose glucocorticoid, Tacrolimus, and intravenous Cyclophosphamide showed 6-month survival benefit compared to a step-up approach (which entailed starting with high dose glucocorticoids and later combining with immunomodulators). Plasmapheresis has been used for patients who have failed combination immunomodulators in multiple small case studies. CONCLUSIONS: Anti-MDA5 associated ILD should be considered in patients with new ILD, since it can present without evidence of DM. Intense multiple drug immune suppression is recommended from the beginning. Plasmapheresis and lung transplant can be considered if patients become refractory to combination immunosuppression. REFERENCE #1: Gupta R, Kumar S, Gow P, Hsien-Cheng Chang L, Yen L. Anti-MDA5-associated dermatomyositis. Intern Med J. 2020 Apr;50(4):484-487. doi: 10.1111/imj.14789. PMID: 32270621. REFERENCE #2: Fiorentino D, Chung L, Zwerner J, Rosen A, Casciola-Rosen L. The mucocutaneous and systemic phenotype of dermatomyositis patients with antibodies to MDA5 (CADM-140): a retrospective study. J Am Acad Dermatol. 2011 Jul;65(1):25-34. doi: 10.1016/j.jaad.2010.09.016. Epub 2011 Apr 29. PMID: 21531040;PMCID: PMC3167687. REFERENCE #3: Hall JC, Casciola-Rosen L, Samedy LA, Werner J, Owoyemi K, Danoff SK, Christopher-Stine L. Anti-melanoma differentiation-associated protein 5-associated dermatomyositis: expanding the clinical spectrum. Arthritis Care Res (Hoboken). 2013 Aug;65(8):1307-15. doi: 10.1002/acr.21992. PMID: 23436757;PMCID: PMC3689861. DISCLOSURES: No relevant relationships by Peter Huh, source=Web Response No relevant relationships by Sudhir Rajan, source=Web Response No relevant relationships by Eduardo Solbes, source=Web Response

CAVITATION DUE TO COVID-19: A CASE OF SECONDARY ATYPICAL MYCOBACTERIAL INFECTION POST-COVID-19

TOPIC: Chest Infections TYPE: Fellow Case Reports INTRODUCTION: The novel Coronavirus disease 2019 pandemic has caused over 2 million deaths worldwide. Two recent systematic reviews and 1 meta-analysis reviewing the CT chest findings of COVID-19 did not reveal cavitation as a common finding with a recent retrospective review estimating the prevalence to be around 3.3%. Among the published examples, about half are solitary cavitary lesions. Most common causative organisms include staphylococcus aureus, klebsiella, and Enterobacter cloacae complex. A recently published case series described 6 cases of co-infection of Mycobacterium tuberculosis with COVID-19 causing cavitary lung disease. We report a case of Mycobacterium Avium Complex (MAC) infection causing cavitary lung disease as a complication of COVID-19 pneumonia. CASE PRESENTATION: 39 year old female with type 2 diabetes and hypothyroidism with a recent diagnosis of COVID-19 and pulmonary embolism. She presented with worsening cough, hemoptysis and left sided chest pain.CT Chest on admission showed a 7cm left lower lobe abscess with an associated pleural effusion and a left lower lobe pulmonary embolism along with scattered ground glass and consolidative opacities. Initial hospital treatment included prednisone, levofloxacin, and apixaban. One week after discharge she was readmitted with worsening left sided chest pain with scant hemoptysis.On readmission, workup included mycobacterial, fungal, auto-immune and HIV tests which were all negative. Patient improved significantly on broad-spectrum antibiotics which included Cefepime and Metronidazole. Laboratory work-up was significant for ESR > 100, CRP of 6 mg/dl. Patient continued to be on room air with improved symptoms and was discharged on oral Augmentin for 4 weeks with plans for outpatient follow-up CT chest. On follow-up, CT chest showed no significant difference in the cavity size and continued to have significant left sided pleuritic chest pain. Her antibiotic course was extended due to the persistence of the cavity and symptoms. At the conclusion of 8 weeks of antibiotics with persistent symptoms, a bronchoscopy was done with a BAL performed in the left lower lobe. AFB cultures grew Mycobacterium Avium Complex. DISCUSSION: Lung cavitation in COVID-19 is an uncommon and so far under-reported consequence/complication. Considering that it might present as a late complication, as in the above case, it is imperative to follow-up these patients closely and consider a broad and appropriate workup. The mechanism of lung cavitation is probably multifactorial, including lung necrosis from the initial pulmonary embolism, effect of initial SARS-CoV2 infection, secondary bacterial, fungal or mycobacterial infection and immunosuppression from initial steroid course. CONCLUSIONS: We report this case to add a secondary atypical mycobacterial infection causing cavitary lung disease to the ever increasing list of late complications of COVID-19 pneumonia. REFERENCE #1: Zoumot, Z. et al. Pulmonary cavitation: an under-recognized late complication of severe COVID-19 lung disease. Bmc Pulm Med 21, 24 (2021). REFERENCE #2: Teng, E., Bennett, L., Morelli, T. & Banerjee, A. An unusual presentation of pulmonary embolism leading to infarction, cavitation, abscess formation and bronchopleural fistulation. Bmj Case Reports 2018, bcr-2017-222859 (2018) REFERENCE #3: Selvaraj, V. & Dapaah-Afriyie, K. Lung cavitation due to COVID-19 pneumonia. Bmj Case Reports 13, e237245 (2020). DISCLOSURES: No relevant relationships by Benjamin Bevill, source=Web Response No relevant relationships by Milind Bhagat, source=Web Response

S2083 A Case of Medication-Induced Black Esophagus

Introduction: Acute esophageal necrosis (AEN), also known as black esophagus, is characterized by diffuse inflammation and necrotic appearance of esophageal mucosa. The pathogenesis has been attributed to a 2-hit hypothesis: a low-flow state creating ischemic injury, followed by an inciting event, such as infection or toxicity. The reported rate of incidence via endoscopy is 0.0125%-0.2%. Here, we describe a case of ischemia and medication-induced AEN in an elderly male. Case Description/Methods: An 83-year-old immunosuppressed male with a past medical history of HTN, insulin-dependent diabetes, CABG, mechanical aortic valve replacement, atrial fibrillation on warfarin, myasthenia gravis (MG) on Cellcept and prednisone, and decompensated cirrhosis with prior duodenal ulcer bleeds who presented with non-bloody emesis and diarrhea. On arrival, he was hemodynamically stable with laboratory results revealing mild AKI and abdominal CT scan showing duodenitis. On the second day, he experienced hematemesis and became progressively lethargic, hypotensive, tachypneic, tachycardic, and febrile. Lab work showed elevated ammonia, lactate, and white cell count. He was intubated for airway protection, resuscitated with IVF, and given broad-spectrum antibiotics, and IV PPI. Repeat abdominal CT scan showed worsening duodenitis without evidence of perforation or abscess. Esophagogastroduodenoscopy (EGD) revealed non-bleeding duodenal ulcers and mucosa with possible ischemic changes involving nearly the entire esophagus (Figure 1). EGD established the diagnosis of AEN, however, biopsy was not performed. Follow-up chest CT showed a moderately diffusely thickened wall of the esophagus without evidence of esophageal perforation. Discussion: Our patient had a host of specific factors for developing AEN. His history of decompensated cirrhosis with recurrent duodenal bleeds predisposed him to develop ischemia, leading to the first hit associated with developing AEN. His history of MG requiring him to take the AEN-associated medication, Cellcept, likely predisposed him to develop toxic injury, leading to the second hit. Due to poor prognosis after declining esophagectomy, the patient was transitioned to comfort care and passed away shortly thereafter.Figure 1.: A. Spindle cell proliferation with myoid differentiation. B. Calcifications arising from the muscularis propria in the upper esophagus on endoscopic ultrasound.

GIRAFFE IN THE COVID-19 LUNG: PULMONARY FIBROSIS LIMITING SEVERITY OF THE PNEUMOTHORAX

TOPIC: Chest Infections TYPE: Medical Student/Resident Case Reports INTRODUCTION: More than a year has passed since the first reported cases of COVID-19 worldwide. We present a case of a patient with COVID-19 who acquired bilateral pulmonary fibrosis then later developed a pneumothorax of the right lung. Ironically, it was this fibrosis that prevented a catastrophic collapse of the lung. CASE PRESENTATION: This is a 60-year-old Caucasian female with hypertension, type II diabetes mellitus and obstructive sleep apnea (OSA) who was admitted due to a four-day history of worsening shortness of breath four days due to COVID pneumonia. She was admitted to the ICU due to worsening respiratory status and was maintained on bi-level positive airway pressure ventilation (BIPAP) for two weeks. Repeated chest radiographs in the ICU showed diffuse infiltrates with ground glass opacities bilaterally. She began to improve on the 3rd week of hospitalization, allowing titration down to high flow nasal cannula with BIPAP at night for OSA. On the 4th week, a routine chest radiograph incidentally revealed a small right apical pneumothorax. She had no desaturations, tachypnea, or increased work of breathing at this time. A CT scan of the chest confirmed the extensive pulmonary fibrosis and ground glass opacities and demonstrated the pneumothorax (Figure 1). A repeat 36 hour chest radiograph (Figure 2) showed expansion of the pneumothorax to a volume of 25% of the right hemithorax, with no signs of tension. The patient's clinical status remained unchanged. Follow-up chest CT scan (Figure 1) showed fibrotic attachments tethering the lungs to the pleura that may have limited its further collapse. Patient underwent a CT-guided pigtail catheter insertion the same day. Follow-up imaging the next day confirmed resolution of the pneumothorax. The pigtail catheter was later removed. The patient remained hospitalized, but improving. DISCUSSION: Pulmonary fibrosis is a known sequelae of COVID pneumonia. Bullae and cyst formation can form as a result of this extensive airspace disease. Secondary spontaneous pneumothorax in COVID-19 could be due to damage to the subpleural alveoli from the formation of cysts and bullae leading to spontaneous alveolar rupture into the pleural space. The use of BIPAP could have contributed to it, due to additional volume and barotrauma. Our patient developed pulmonary fibrosis after remaining hospitalized for more than 4 weeks. The fibrosis caused the lung to tether to portions of the pleura, preventing a quick, catastrophic collapse of the lung. The delay in progression gave the patient an opportunity to undergo a CT-guided pigtail catheter insertion, as opposed to an emergent chest tube thoracostomy which would have been a more invasive, traumatic, and painful procedure. CONCLUSIONS: This case highlights the possibility of extensive lung fibrosis, via thick pleural adhesions, protecting patients from developing fatal pneumothorax. REFERENCE #1: Wu, C., et al., Risk Factors Associated With Acute Respiratory Distress Syndrome and Death in Patients With Coronavirus Disease 2019 Pneumonia in Wuhan, China. JAMA Intern Med, 2020. 180(7): p. 934-943. REFERENCE #2: Rai, D.K., P. Sharma, and R. Kumar, Post covid 19 pulmonary fibrosis- Is it reversible? Indian Journal of Tuberculosis, 2020. REFERENCE #3: Martinelli, A.W., et al., COVID-19 and pneumothorax: a multicentre retrospective case series. Eur Respir J, 2020. 56(5) DISCLOSURES: No relevant relationships by Patrick Benjamin, source=Web Response No relevant relationships by Marvyn Allen Chan, source=Web Response No relevant relationships by Josemaria Demigillo, source=Web Response No relevant relationships by Ma Pamela Demigillo, source=Web Response No relevant relationships by Stephen Jesmajian, source=Web Response No relevant relationships by Junfeng Xue, source=Web Response