• MRSA cellulitis
• acute fibrinous and organizing pneumonia
• ground‐glass opacities

• COVID-19
• Coronavirus disease 2019
• Organizing pneumonia
• SARS-CoV-2
• Secondary organizing pneumonia
• Severe acute respiratory syndrome coronavirus 2

• Adrenal Cortex Hormones
• COVID-19
• Humans
• Lung
• Pneumonia/diagnosis
• Pneumonia/drug therapy
• SARS-CoV-2

• ACE2, angiotensin-converting enzyme 2
• AFOP, acute fibrinous and organizing pneumonia
• ARDS, acute respiratory distress syndrome
• COVID-19
• COVID-19 related acute respiratory distress syndrome
• COVID-19, coronavirus infectious disease
• DAD, diffuse alveolar damage
• HE, hematoxylin–eosin
• Histopathology
• ISH, in situ hybridization
• NMBD, neuromuscular blocking drugs
• RT-PCR, Reverse Transcriptase-Polymerase chain reaction
• SAPSII, simplified acute physiology score
• SARS-CoV-2
• SOFA, Sequential Organ Failure Assessment
• VILI, ventilator induced lung injury

• COVID-19
• COVID-19 related acute respiratory distress syndrome
• Histopathology
• Histopatología
• SARS-CoV-2
• Síndrome de dificultad respiratoria aguda asociada a COVID-19

• Aged
• B-Lymphocytes
• Biopsy
• COVID-19/complications
• COVID-19/pathology
• Female
• Humans
• Lung/pathology
• Lung/virology
• Male
• Middle Aged
• Prospective Studies
• Respiration, Artificial/statistics & numerical data
• Respiratory Distress Syndrome/etiology
• Respiratory Distress Syndrome/pathology
• SARS-CoV-2/isolation & purification
• T-Lymphocytes
• Tertiary Care Centers
• Time Factors

• acute fibrinous
• corticosteroids
• organizing pneumonia
• pneumonia

• Biopsy
• Glucocorticoids/therapeutic use
• Humans
• Idiopathic Interstitial Pneumonias/diagnosis
• Idiopathic Interstitial Pneumonias/drug therapy
• Idiopathic Interstitial Pneumonias/pathology
• Male
• Middle Aged

• Acute lung injury
• GABA(A)R
• Propofol

Since the acute fibrinous and organizing pneumonia (AFOP) was first described by Beasley in 2002, some case reports of patients aged from 38 d to 80 years have been published worldwide, but there is still no standard therapy for this disease and the treatment methods remain controversial. Both steroid and immunosuppressive agents, such as cyclophosphamide or mycophenolate mofetil, have been reported to be effective in some studies, but with many side effects, especially in patients of advanced age.

We herein report an 81-year-old female patient who was admitted to our hospital due to dry cough, and breathlessness for 1 mo. She was treated with broad-spectrum antibiotics and anti-fungal therapy, but without improvement in both symptoms and radiological findings, and her respiratory status worsened, and she required bed rest almost the whole day. Computed tomography-guided percutaneous needle lung biopsy was performed and histopathology examination confirmed the diagnosis of AFOP. She was then successfully treated with a steroid monotherapy, which resulted in a satisfactory clinical outcome without serious complications.

We conclude that complete remission of AFOP can be achieved by steroid monotherapy in patients of advanced age.

• Acute fibrinous and organizing pneumonia
• Geriatric
• Steroid
• Computed tomography-guided percutaneous needle lung biopsy
• Case report

• Acute fibrinous and organizing pneumonia
• CT patterns
• Histopathological pattern
• Primary Sjögren’s syndrome

• Female
• Glucocorticoids/therapeutic use
• Humans
• Methylprednisolone/therapeutic use
• Middle Aged
• Pneumonia/drug therapy
• Pneumonia/etiology
• Pneumonia/pathology
• Prednisone/therapeutic use
• Sjogren's Syndrome/complications
• Sjogren's Syndrome/drug therapy

Acute fibrinous and organizing pneumonia (AFOP) is a unique pathological entity with intra-alveolar fibrin in the form of “fibrin balls” and organizing pneumonia. It was divided into rare idiopathic interstitial pneumonia according to the classification notified by American Thoracic Society/European Respiratory Society in 2013. As a rare pathological entity, it is still not well known and recognized by clinicians. We reviewed the clinical features of 20 patients with AFOP diagnosed in a teaching hospital.

The medical records of 20 patients with biopsy-proven diagnosis of AFOP were retrospectively reviewed. The patients’ symptoms, duration of the disease, comorbidities, clinical laboratory data, pulmonary function testing, radiographic studies, and the response to treatment were extracted and analyzed.

Fever was the most common symptom and was manifested in 90% of AFOP patients. For clinical laboratory findings, systematic inflammatory indicators, including C-reactive protein and erythrocyte sedimentation rate, were significantly higher than normal in AFOP patients. In accordance with this increased indicators, injured liver functions were common in AFOP patients. Inversely, AFOP patients had worse clinical conditions including anemia and hypoalbuminemia. For pulmonary function testing, AFOP patients showed the pattern of restrictive mixed with obstructive ventilation dysfunction. For high-resolution computerized tomography (HRCT) findings, the most common pattern for AFOP patients was lobar consolidation which was very similar to pneumonia. However, unlike pneumonia, AFOP patients responded well to glucocorticoids.

Patients with AFOP manifest as acute inflammatory-like clinical laboratory parameters and lobar consolidation on HRCT, but respond well to steroid.

• ARDS
• Crazy paving
• ECCO(2)R
• Novalung(®)
• Organizing pneumonia
• Pneumonie organisée
• SDRA

• Carbon Dioxide/pharmacokinetics
• Extracorporeal Membrane Oxygenation/methods
• Female
• Humans
• Intensive Care Units
• Life Support Care/methods
• Middle Aged
• Pneumonia/pathology
• Pneumonia/therapy
• Respiratory Distress Syndrome/etiology
• Respiratory Distress Syndrome/therapy
• Severity of Illness Index

Acute fibrinous and organizing pneumonia (AFOP) is an extremely rare, relatively new, and distinct histological pattern of acute lung injury characterized predominately by the presence of intra-alveolar fibrin and associated organizing pneumonia. AFOP may be idiopathic or associated with a wide spectrum of clinical conditions. It has a variable clinical presentation from mild respiratory symptoms to that similar to the acute respiratory distress syndrome. Currently there is no consensus on treatment, and corticosteroids previously were of unclear benefit. To date, there are less than 40 cases of AFOP reported in the literature and only one has been linked to hematopoietic stem cell transplantation. Here we report the first case series of 2 patients who developed AFOP following allogenic stem cell transplant that were successfully treated with high-dose corticosteroids.

• AFOP
• ARDS
• BOOP
• allogenic stem cell transplant
• diffuse alveolar damage

• Acute fibrinous and organizing pneumonia
• Interstitial lung diseases

• Antibodies, Antinuclear/immunology
• Asbestos
• Connective Tissue Diseases/diagnosis
• Connective Tissue Diseases/immunology
• Connective Tissue Diseases/therapy
• Glass
• Humans
• Immunosuppressive Agents/therapeutic use
• Lung/diagnostic imaging
• Lung/pathology
• Lung Diseases, Interstitial/diagnosis
• Lung Diseases, Interstitial/therapy
• Lung Transplantation
• Male
• Middle Aged
• Occupational Exposure
• Oxygen Inhalation Therapy
• Tomography, X-Ray Computed
• Waiting Lists

• acute fibrinous and organizing pneumonia
• myelodysplastic syndromes
• mechanical ventilation
• corticosteroid monotherapy

• Anti-Inflammatory Agents/administration & dosage
• Anti-Inflammatory Agents/therapeutic use
• Cryptogenic Organizing Pneumonia/complications
• Cryptogenic Organizing Pneumonia/diagnosis
• Cryptogenic Organizing Pneumonia/diagnostic imaging
• Cryptogenic Organizing Pneumonia/drug therapy
• Diagnosis, Differential
• Fever/etiology
• Humans
• Male
• Middle Aged
• Myelodysplastic Syndromes/complications
• Prednisolone/administration & dosage
• Prednisolone/therapeutic use
• Ventilator Weaning

Acute Fibrinous and Organizing Pneumonia is a rare entity characterized by the histological pattern suggestive of diffuse alveolar damage, eosinophilic pneumonia and organizing pneumonia; the presence of intra alveolar “fibrin balls” distinguishes it from these conditions. Herein, we describe the association of acute fibrinous and organizing pneumonia with a respiratory tract infection. We believe that such an association has been extremely rarely described.

We report the case of a 68 year old female patient of Afghan descent who presented with shortness of breath, cough and high grade fever not responding satisfactorily to standard antibiotic therapy. Imaging revealed bilateral basilar infiltrates and ground glass opacification of the right lower lung zone. Though the inflammatory markers decreased with antibiotic therapy, there was minimal improvement in the patient’s symptoms and radiological appearance of the lungs. Bronchoscopy was refused by the patient’s family and a Computed Tomography guided biopsy of the lung revealed a histological diagnosis of acute fibrinous and organizing pneumonia. Patient was initiated on high dose intravenous corticosteroid therapy followed by a maintenance dose of prednisolone at 40 mg/day. She recovered dramatically. However, due to poor compliance with treatment, she relapsed and was re-treated with the same regimen. Currently she is completely symptom free and is on a tapering corticosteroid dose.

We conclude that AFOP may be a rare but under diagnosed entity and recommend that it should be considered in the differentials of a suspected pulmonary infection unresponsive to optimum antibiotic therapy.

Acute fibrinous and organizing pneumonia (AFOP) is a very rare pathological entity of lung injury characterized by intra-alveolar fibrin balls.

Hemeoxygenase (HO) -1 is a cytoprotective enzyme against oxidative stress and inflammation. It is known to be expressed in the alveolar macrophages in the healthy adults and overexpressed in other various lung cells of the lung injury patients.

We experienced two cases of subacute form AFOP for these 10 years and reviewed clinico-pathological characteristics. The average age was 62 years old and both were male. The etiology of both cases was idiopathic. The average PaO₂/F_IO₂ ratio was 274.5 ± 84.1. The average levels of C-reactive protein and surfactant protein - A of the serum were elevated to 19.8 ± 6.3 mg/dL and 67.6 ± 15.8 ng/mL, respectively. Serum sialylated carbohydrate antigen levels were normal in both cases. The characteristic radiographic findings were bilateral consolidations and ground glass opacities. Lung biopsy specimens revealed fibrin balls and alveolitis with abundant cellular HO-1 expression. Steroid response was excellent and the pulmonary involvements absolutely disappeared for about 3 months.

• Acute fibrinous and organizing pneumonia
• Corticosteroid
• Diffuse alveolar damage
• Fibrin balls
• Hemeoxygenase-1
• Organizing pneumonia
• Pulmonary cellular protection