Platypnea-Orthodeoxia Syndrome after SARS-CoV-2 interstitial pneumonia: an overview and an update on our patient.

Platypnea-Orthodeoxia Syndrome (POS) is a clinical entity defined as positional dyspnoea (platypnea) and arterial desaturation (orthodeoxia) that occurs when sitting or standing up and usually resolves by lying down. Up to April 25th 2021, eleven cases of POS after SARS-CoV-2 pneumonia have been reported on Pubmed. Accordingly, SARS-CoV-2 infection may be considered as an emergent cause of POS due to an increase in ventilation/perfusion (V/Q) mismatch. In this article we provide an update on the patient with POS after fibrotic evolution of SARS-CoV-2 interstitial pneumonia, which we previously reported and we discuss the case reports of POS due to SARS-CoV-2 infection.

Streak artefacts in Computed Tomography Urography: Comparative evaluation between two different iodinated contrast media.

INTRODUCTION: The objective of this study was to compare the frequency and entity, in computed tomography (CT) urography, of streak artefacts on the urinary tract generated by two contrast agents with a different iodine concentration and osmolarity. METHODS: Computed tomography scans including an excretory renal phase, performed on adult subjects in the period May-July 2020, were retrospectively evaluated in consensus by three expert radiologists, to detect any streak artefacts located in the urinary tract. Patients were administered either 1.6 mL/kg of Iodixanol 320 mgI/mL or 1.3 mL/kg of Iomeprol 400 mgI/mL. RESULTS: In total, 144 CT scans were analysed, subdivided into two groups administered either Iodixanol (71/144 (49.3%) patients) or Iomeprol (73/144 (50.7%) patients). In 41% cases, no beam hardening artefacts were found; among these, 12/59 (20.3%) patients had received Iodixanol and 47/59 (79.7%) Iomeprol. In the Iodixanol group, the mean contrast density on the renal pelvis was 2565.6 HU and streak artefacts occurred in 59/71 cases (83.1%); in 33/59 (55.9%) cases, the artefacts were marked, and in 26/59 (44.1%) minimal. In the Iomeprol group, the mean contrast density on the renal pelvis was 1666 HU and streak artefacts occurred in 26/73 cases (35.6%); in 7/26 (27%) cases, the artefacts were marked and in 19/26 (73%) minimal. CONCLUSION: The study data demonstrate a significant difference in the attenuation values of iodine urine in the excretory system between the Iodixanol and Iomeprol group. Iodixanol induced a higher frequency and burden of artefacts, compared to Iomeprol.

Platypnea-orthodeoxia after fibrotic evolution of SARS-CoV-2 interstitial pneumonia. A case report.

Platypnea-orthodeoxia syndrome (POS) is a clinical entity characterized by positional dyspnoea (platypnea) and arterial desaturation (orthodeoxia) that occurs when sitting or standing up and usually resolves by lying down. POS may result from some cardiopulmonary disorders or from other miscellaneous aetiologies. We report a case of POS in a patient after fibrotic evolution of SARS-CoV-2 interstitial pneumonia associated with pulmonary embolism. The patient did not have any evidence of an intracardiac/intrapulmonary shunt.