Cryptogenic Organizing Pneumonia: Evolution of Morphological Patterns Assessed by HRCT

Abstract

To evaluate the radiological findings in patients with cryptogenic organizing pneumonia (COP) before steroid treatment and their behavior after therapy, we retrospectively evaluated a total of 22 patients with a diagnosis of COP made by bronchoalveolar lavage (BAL), biopsy or clinical/radiological features, and the patients were followed between 2014 and 2018 at the hospital; the demographic data, symptoms, radiologic findings, diagnostic methods and treatment plans of patients were collected from patients’ hospital records. At least two CT scans of 22 patients (16 female and six men) were evaluated, the first one before starting steroid therapy and the others after therapy. At baseline CT scans, the most common radiological finding was the presence of consolidations (18/22 patients, 81.8%); ground-glass opacities were also very common (15/25, 68.1%). The other findings were as follows: nodules and masses (5/22, 22.7%), atoll sign (4/22, 18.1%), perilobular pattern (3/22, 13.6%) and parenchymal bands (3/22, 13.6%). Two patients had a significant relapse after reducing/interrupting therapy, while three had a complete resolution and are not currently under therapy (maintenance of clinical remission with no oral corticosteroid (OCS)). In High-resolution computed tomography (HRCT) scans after therapy, consolidations were still observable in seven patients (five in new areas of the lung-migratory infiltrates), while most of them disappeared, leaving a residual area of ground glass opacity in two patients. One patient had a residual of the perilobular pattern, with the disappearing of the other findings (consolidations and ground-glass opacities). Two patients developed a fibrosing pattern despite the therapy (9.5%). Cryptogenic organizing pneumonia tends to respond to oral corticosteroid treatment, but some patients may have a null or partial response. We highlight the behavior of this disease after proper therapy.

Comparison of clinical features and prognosis in patients with cryptogenic and secondary organizing pneumonia

“…SOP was defined as OP secondary to lung injury of known etiology. The chest CT findings of OP were classified as follows; consolidation, ground glass opacity (GGO), mixed of consolidation and GGO, nodule or mass, perilobular opacity, parenchymal bands or fibrotic pattern, reversed halo sign, mediastinal lymphadenopathy and pleural effusion [ 6 , 17 , 18 ]. Perilobular opacity was defined as curved or polygonal opacities with poorly defined margins around the interlobular septa.…”

Radiologic aspects of COVID-19 pneumonia: Outcomes and thoracic complications

“…Other late findings are: The inverted halo or atoll sign, seen in 4%–5% of cases. 5 , 16 It is a finding that suggests the presence of organising pneumonia, 15 , 34 although it should also raise suspicion of the possibility of pulmonary infarctions 18 ( Fig. 5 E and F).…”

“…They may represent subsegmental atelectasis or secondary organising pneumonia. 22 , 34 A reticular pattern can also develop late, 14 , 26 , 27 and is seen in 6% of patients, after the fourth week of the disease 22 ( Fig. 4 E).…”

“…This finding also suggests secondary organising pneumonia. 15 , 22 , 34

Figure 3 Common findings in the first two weeks of the disease. A) Mixed ground-glass (arrow) and consolidation (arrow tip) opacities, predominantly posterior, with linear margins showing a geographic pattern.

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Multidisciplinary Approach to Interstitial Lung Diseases: Nothing Is Better than All of Us Together

“…The whole matter is further complicated by the pleiomorphisms of radiological presentations in different ILDs, but also in the same disease at different stages. Tiralongo et al describe the evolution of morphological patterns at HRCT in cryptogenic organizing pneumonia in response to treatment with steroids [ 5 ]. Aquilina et al have instead focused their attention on cystic lung diseases, one of the most typical radiological presentations of ILDs [ 6 ].…”