The Findings of Pulmonary Nocardiosis on Chest High Resolution Computed Tomography: Single centre experience and review of literature.

Objectives: Pulmonary nocardiosis is a rare opportunistic infection that is often encountered in immunocompromised patients, in particular those with the HIV infection and in solid organ transplant recipients. As the number of immunocompromised patients increase, the number of patients with pulmonary nocardiosis is also expected to increase. This study aimed to analyse both the chest high resolution computed tomography (HRCT) findings of patients with confirmed pulmonary nocardiosis and review the imaging features of pulmonary nocardiosis in the literature. Methods: This retrospective study was conducted at The Royal Hospital, Muscat, Oman, to identify patients with a diagnosis of pulmonary nocardiosis between January 2006 and January 2019. Accordingly, nine patients with pulmonary nocardiosis were identified, but three patients were excluded as no chest HRCT images were available. Patient clinical presentation was recorded and chest HRCT images were retrospectively reviewed. Results: A total of six patients were enrolled in this study. All were male and with a mean age of 41 ± 11 years. Three patients were immunocompromised, two of whom had undergone a renal transplant. The main HRCT findings were cavitary nodules/masses, non-cavitary nodules/masses, septal thickening, centrilobular nodules, ground glass opacities, consolidation, pleural effusion, pleural thickening, enlarged lymph nodes and necrotic lymph nodes. Conclusion: Pulmonary nocardiosis shows various findings in a chest CT, the most common of which are pulmonary nodules and masses. Awareness of these findings can help radiologists with a diagnosis in the appropriate clinical settings.

COVID-2019 Pneumonia: Severity and distribution of lung changes observed on the initial chest X-ray as an indicator of final outcomes.

Objectives: This study aimed to assess the correlation between the severity of the initial chest x-ray (CXR) abnormalities in patients with a confirmed diagnosis of COVID-19 and the final outcomes. Methods: This retrospective study was conducted at the Royal Hospital, Oman between mid-March and May 2020 and included patients who had been admitted with a confirmed diagnosis of COVID-19 and had a final outcome. Serial CXRs were identified and examined for presence, extent, distribution and progression pattern of radiological abnormalities. Each lung field was divided into three zones on each CXR and a score was allocated for each zone (0 is normal and 1-4 is mild-severe). The scores for all six zones per CXR examination were summed to provide a cumulative chest radiographic score (range: 0-24). Results: A total of 64 patients were included; the majority were male (89.1%) and the mean age was 50.22 ± 14.86 years. The initial CXR was abnormal in 60 patients (93.8%). The most common finding was ground glass opacity (n = 58, 96.7%) followed by consolidation (n = 50, 83.3%). Most patients had bilateral (n = 51, 85.0%), multifocal (n = 57, 95.0%) and mixed central and peripheral (n = 36, 60.0%) lung abnormalities. The median score of initial CXR for deceased patients was significantly higher than recovered patients (17 versus 11; P = 0.009). Five CXR evolution patterns were identified: type I (initial radiograph deteriorates then improves), type II (fluctuate), type III (static), type IV (progressive deterioration) and type V (progressive improvement). Conclusion: A higher baseline CXR score is associated with higher mortality rate and poor prognosis in those with COVID-19 pneumonia.