title: A very rare cause of dyspnea with a unique presentation on a computed tomography scan of the chest: macrophage activation syndrome.
abstract: Macrophage activation syndrome is a rare and potentially life-threatening disease. It occurs due to immune dysregulation manifested as excessive macrophage proliferation, typically causing hepatosplenomegaly, pancytopenia and hepatic dysfunction. Here, we report an unusual case of macrophage activation syndrome presenting as dyspnea, as well as (reported here for the first time) high resolution computed tomography findings of an excavated nodule, diffuse ground glass opacities and consolidations (mimicking severe pneumonia or alveolar hemorrhage). The patient was successfully treated with human immunoglobulin. We recommend that macrophage activation syndrome be considered in the differential diagnosis of respiratory failure. Rapid diagnosis and treatment are essential to achieving favorable outcomes in patients with this syndrome.
authors.affiliation: Clinical Emergency Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - HCFMUSP, University of São Paulo School of Medicine Hospital das Clínicas - São Paulo, Brazil.
authors.forename: Rodrigo Antônio
authors.initials: RA
authors.lastname: Brandão-Neto
authors.forename: Alfredo Nicodemos Cruz
authors.initials: AN
authors.lastname: Santana
authors.forename: Debora Lucia Seguro
authors.initials: DL
authors.lastname: Danilovic
authors.forename: Fabíola Del Carlo
authors.initials: Fdel C
authors.lastname: Bernardi
authors.forename: Carmen Silvia Valente
authors.initials: CS
authors.lastname: Barbas
authors.forename: Berenice Bilharinho
authors.initials: BB
authors.lastname: de Mendonça
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000175:diagnosis*; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000175:diagnosis*; D008214:Lymphocytes / Q000473:pathology; D051359:Lymphohistiocytosis, Hemophagocytic / Q000175:diagnosis*; D008262:Macrophage Activation; D008297:Male; D013577:Syndrome; D014057:Tomography, X-Ray Computed / Q000379:methods*