INTRODUCTION: Acute fibrinous and organizing pneumonia (AFOP) is a rare histologic variant of acute lung injury. Its clinical features, sequelae, and management are not well described. The patient presented is unique in that he had co-existing invasive pulmonary aspergillosis (IPA) and underlying acute myeloid leukemia (AML).
CASE PRESENTATION: A 42 year old Vietnamese man with AML diagnosed by bone marrow biopsy two months prior, presented to the oncology clinic with subjective fevers and chills for 1 day. He had undergone two rounds of induction chemotherapy with idarubicin and ara-c. He is hepatitis C+, a hepatitis B carrier, and HIV negative. He emigrated to the United States 26 years ago and works in landscaping. He has a 10 pack year smoking history, has 2 alcohol containing drinks per night, no history of illicit drug use, and is not sexually active. The physical exam was positive for fever (39.5°C), tachycardia and tachypnea. The white blood cell count was 0.700/mm3, with an absolute neutrophil count of zero/mm3. The hematocrit was 25.3%, and the platelet count was 8000/mm3. He was started on broad spectrum antibiotics, antifungal and antiviral therapy. A chest x-ray showed multiple patchy infiltrates bilaterally and a chest CT showed multifocal parenchymal masses (1.6 cm spiculated right upper lobe mass, pleural based 1.7 cm mass in the superior segment of the left lower lobe, and a 2.5 cm spiculated left lower lobe mass). The patient underwent flexible bronchoscopy followed by a left posterior thoracotomy and wedge resection of the superior segment of the left lower lobe. The biopsy showed the alveolar spaces to be filled with fibrinous material arranged in the form of “fibrin” balls. Based on this, a diagnosis of AFOP was made. Additionally, there was co-existing IPA. The patient was treated with 5 months of oral voriconazole with resolution of his symptoms and complete resolution of the parenchymal masses on follow up chest CT. The patient did not receive oral or parenteral corticosteroids.
DISCUSSIONS: AFOP was first described in 2002, by Beasley (1) as an unusual histologic variant of acute lung injury. Histologically, it differs from the well described patterns of diffuse alveolar damage (DAD) and organizing pneumonia. In AFOP the alveolar spaces are filled with fibrinous material, arranged in the form of “fibrin” balls. Its onset can be acute and fulminant, with death occurring in 1–5 weeks, or subacute, with ensuing recovery. Typical radiographic reports describe bibasilar infiltrates. In contrast, this patient's chest CT showed multifocal parenchymal masses. This patient's biopsy not only showed AFOP but was remarkable for the coexistence of IPA. Whereas other case reports have described the successful treatment of AFOP with long term steroid therapy, this patient was not treated with steroids. Therapy was targeted at the IPA with oral voriconazole with complete resolution of the radiographic abnormalities as well as the clinical syndrome.
CONCLUSION: Acute Fibrinous and Organizing Pneumonia is a newly described pathologic entity likely related to acute lung injury. As with DAD, treatment of the underlying cause may be sufficient to allow resolution to occur. The patient described had complete resolution with therapy directed only at the pulmonary aspergillosis. This newly described entity will need to be better characterized to determine its etiology, associations, clinical features, radiographic presentations, and optimum management. We believe this case helps expand our understanding of the clinical presentation of AFOP.
DISCLOSURE: Sunil Rajan, No Financial Disclosure Information; No Product/Research Disclosure Information