COVID-19 mimics on chest CT: a pictorial review and radiologic guide.

Chest imaging is often used as a complementary tool in the evaluation of coronavirus disease 2019 (COVID-19) patients, helping physicians to augment their clinical suspicion. Despite not being diagnostic for COVID-19, chest CT may help clinicians to isolate high suspicion patients with suggestive imaging findings. However, COVID-19 findings on CT are also common to other pulmonary infections and non-infectious diseases, and radiologists and point-of-care physicians should be aware of possible mimickers. This state-of-the-art review goal is to summarize and illustrate possible etiologies that may have a similar pattern on chest CT as COVID-19. The review encompasses both infectious etiologies, such as non-COVID viral pneumonia, Mycoplasma pneumoniae, Pneumocystis jiroveci, and pulmonary granulomatous infectious, and non-infectious disorders, such as pulmonary embolism, fat embolism, cryptogenic organizing pneumonia, non-specific interstitial pneumonia, desquamative interstitial pneumonia, and acute and chronic eosinophilic pneumonia.

Clinical, radiographic and hematological characteristics of Mycoplasma pneumoniae pneumonia.

OBJECTIVE: To describe the clinical, hematological and radiographic characteristics of children hospitalized for Mycoplasma pneumoniae pneumonia. METHOD: The study population consisted of 190 children between 3 months and 16 years old, hospitalized for radiographically confirmed pneumonia. Patients were divided into two groups, to wit: 95 children with Mycoplasma pneumoniae pneumonia, as diagnosed using the enzyme-linked immunosorbent assay (ELISA) method; and 95 children with pneumonia caused by other etiologic agents. Using a validated scoring system, the clinical, hematological and radiographic findings of both groups were compared to differentiate Mycoplasma pneumoniae pneumonia (group 1) from pneumonia caused by other etiologic agents (group 2), itself divided into two groups, bacterial (n = 75) and viral (n = 20). RESULTS: Mycoplasma pneumoniae pneumonia was found most often in girls (p < 0.01), older children (p < 0.01), and patients with dry cough (p < 0.01) and extrapulmonary manifestations (p < 0.01). The clinical, hematological and radiographic variables of Mycoplasma pneumoniae pneumonia (mean score = 6.95) scored between those found in bacterial (mean score = 8.27) and viral pneumonia (mean score = 0.90). CONCLUSION: Results suggest that the scoring system can contribute to the presumptive diagnosis of Mycoplasma pneumoniae pneumonia and help differentiate pneumonic status caused by other etiologic agents.