INTERSTITIAL LUNG DISEASE IN A TODDLER WITH ANTI-MDA5 JUVENILE DERMATOMYOSITIS THAT IMPROVED WITH AGGRESSIVE, EARLY TREATMENT WITH STEROIDS AND MULTIPLE IMMUNOSUPPRESSANTS

Abstract

SESSION TITLE: Pulmonary Manifestations of Autoimmune Diseases and MalignanciesSESSION TYPE: Case ReportsPRESENTED ON: 10/18/2022 11:15 am - 12:15 pmINTRODUCTION: Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody is associated with Rapidly Progressive Interstitial Lung Disease (RP-ILD) in amyopathic dermatomyositis and has a high mortality rate. The clinical phenotype of anti-MDA5 juvenile dermatomyositis (JDM) was comparable to adults, both with a high rate of ILD. Here, we report a case of anti-MDA-5 JDM diagnosed in a toddler, complicated with RP-ILD which resolved after aggressive immunosuppressive therapy.CASE PRESENTATION: 3-year-old male with a medical history of asthma who initially presented with multiple erythematous patches on the face, arms, elbows, and extensor surfaces of both knees for 3 months. Multiple erythematous papules noted on the dorsal and palmar side of finger joints clinically consistent with Gottron papules led to the diagnosis of juvenile dermatomyositis. He had normal muscle strength and muscle enzyme levels including creatinine kinase, aldolase, and lactate dehydrogenase. Given history of chronic non-productive cough, a chest X-ray was obtained and revealed signs of increased interstitial lung markings. Myositis-specific antibody panel revealed anti-MDA5 positivity. Chest CT was then performed and revealed ground-glass opacities in the left lower lobe and bronchial wall thickening consistent with interstitial lung disease. His initial therapy included a tapering course of prednisolone, mycophenolate mofetil, and IVIG 2 grams/kilogram every 4 weeks. After 3 months of treatment, his skin disease significantly improved, however, a repeat chest CT revealed an interval increased opacity in the left lower lobe with a new inflammatory lesion in the left upper lobe. Treatment was escalated by adding one dose of rituximab 750 milligrams/m2 and IVIG was increased to every 3 weeks. Hydroxychloroquine was started due to a flare of the rash. Six months later, chest CT revealed significant improvement of the lung opacity. The most recent chest CT performed at 24 months on therapy revealed near-complete resolution of airspace opacity.DISCUSSION: Anti-MDA5 antibody juvenile dermatomyositis is associated with RP-ILD, cutaneous rash, and less severe muscle involvement. MDA5 is an RNA viral binding protein that activates the viral immune response. There is limited data on treatment modalities for children especially toddlers presenting with this condition with no documented case of anti MDA5 JDM in children less than 8 years of age. Patients with anti-MDA5 antibody have a high mortality rate from ILD if left untreated. Aggressive immunosuppressive therapy is warranted along with frequent imaging to assess treatment response.CONCLUSIONS: In this case, we present a 3-year-old child with anti-MDA5 juvenile dermatomyositis and ILD. We successfully treated our patient with corticosteroids, mycophenolate mofetil, hydroxychloroquine, IVIG, and rituximab following which there was the resolution of his lung disease.Reference #1: Kurtzman DJB, Vleugels RA. Anti-melanoma differentiation–associated gene 5 (MDA5) dermatomyositis: A concise review with an emphasis on distinctive clinical features. Journal of the American Academy of Dermatology. 2018;78(4):776-785. doi:10.1016/J.JAAD.2017.12.010Reference #2: Kobayashi I, Okura Y, Yamada M, Kawamura N, Kuwana M, Ariga T. Anti-Melanoma Differentiation-Associated Gene 5 Antibody is a Diagnostic and Predictive Marker for Interstitial Lung Diseases Associated with Juvenile Dermatomyositis. The Journal of Pediatrics. 2011;158(4):675-677. doi:10.1016/J.JPEDS.2010.11.033Reference #3: Sato S, Hirakata M, Kuwana M, et al. Autoantibodies to a 140-kd polypeptide, CADM-140, in Japanese patients with clinically amyopathic dermatomyositis. Arthritis and rheumatism. 2005;52(5):1571-1576. doi:10.1002/ART.21023DISCLOSURES: No relevant relationships by Allen Joeno disclosure on file for Nathan Kraynack;No relevant relationships by Sirada Panupattanapong SESSION TITLE: Pulmonary Manifestations of Autoimmune Diseases and Malignancies SESSION TYPE: Case Reports PRESENTED ON: 10/18/2022 11:15 am - 12:15 pm INTRODUCTION: Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody is associated with Rapidly Progressive Interstitial Lung Disease (RP-ILD) in amyopathic dermatomyositis and has a high mortality rate. The clinical phenotype of anti-MDA5 juvenile dermatomyositis (JDM) was comparable to adults, both with a high rate of ILD. Here, we report a case of anti-MDA-5 JDM diagnosed in a toddler, complicated with RP-ILD which resolved after aggressive immunosuppressive therapy. CASE PRESENTATION: 3-year-old male with a medical history of asthma who initially presented with multiple erythematous patches on the face, arms, elbows, and extensor surfaces of both knees for 3 months. Multiple erythematous papules noted on the dorsal and palmar side of finger joints clinically consistent with Gottron papules led to the diagnosis of juvenile dermatomyositis. He had normal muscle strength and muscle enzyme levels including creatinine kinase, aldolase, and lactate dehydrogenase. Given history of chronic non-productive cough, a chest X-ray was obtained and revealed signs of increased interstitial lung markings. Myositis-specific antibody panel revealed anti-MDA5 positivity. Chest CT was then performed and revealed ground-glass opacities in the left lower lobe and bronchial wall thickening consistent with interstitial lung disease. His initial therapy included a tapering course of prednisolone, mycophenolate mofetil, and IVIG 2 grams/kilogram every 4 weeks. After 3 months of treatment, his skin disease significantly improved, however, a repeat chest CT revealed an interval increased opacity in the left lower lobe with a new inflammatory lesion in the left upper lobe. Treatment was escalated by adding one dose of rituximab 750 milligrams/m2 and IVIG was increased to every 3 weeks. Hydroxychloroquine was started due to a flare of the rash. Six months later, chest CT revealed significant improvement of the lung opacity. The most recent chest CT performed at 24 months on therapy revealed near-complete resolution of airspace opacity. DISCUSSION: Anti-MDA5 antibody juvenile dermatomyositis is associated with RP-ILD, cutaneous rash, and less severe muscle involvement. MDA5 is an RNA viral binding protein that activates the viral immune response. There is limited data on treatment modalities for children especially toddlers presenting with this condition with no documented case of anti MDA5 JDM in children less than 8 years of age. Patients with anti-MDA5 antibody have a high mortality rate from ILD if left untreated. Aggressive immunosuppressive therapy is warranted along with frequent imaging to assess treatment response. CONCLUSIONS: In this case, we present a 3-year-old child with anti-MDA5 juvenile dermatomyositis and ILD. We successfully treated our patient with corticosteroids, mycophenolate mofetil, hydroxychloroquine, IVIG, and rituximab following which there was the resolution of his lung disease. Reference #1: Kurtzman DJB, Vleugels RA. Anti-melanoma differentiation–associated gene 5 (MDA5) dermatomyositis: A concise review with an emphasis on distinctive clinical features. Journal of the American Academy of Dermatology. 2018;78(4):776-785. doi:10.1016/J.JAAD.2017.12.010 Reference #2: Kobayashi I, Okura Y, Yamada M, Kawamura N, Kuwana M, Ariga T. Anti-Melanoma Differentiation-Associated Gene 5 Antibody is a Diagnostic and Predictive Marker for Interstitial Lung Diseases Associated with Juvenile Dermatomyositis. The Journal of Pediatrics. 2011;158(4):675-677. doi:10.1016/J.JPEDS.2010.11.033 Reference #3: Sato S, Hirakata M, Kuwana M, et al. Autoantibodies to a 140-kd polypeptide, CADM-140, in Japanese patients with clinically amyopathic dermatomyositis. Arthritis and rheumatism. 2005;52(5):1571-1576. doi:10.1002/ART.21023 DISCLOSURES: No relevant relationships by Allen Joe no disclosure on file for Nathan Kraynack; No relevant relationships by Sirada Panupattanapong