Metal Fume Fever: An Underdiagnosis.

Metal fume fever (MFF) is an auto-limited acute febrile respiratory syndrome that may mimic an acute viral respiratory disease after exposure to the fumes of metal oxides. Due to the similar presentation of an influenza-like illness, it remains an underdiagnosed disease. It is typically a benign and self-limited entity that resolves over 12-48 hours following cessation of exposure, but symptoms may reoccur with repeated exposure. Supportive and symptomatic care is recommended.

Morvan's Syndrome: The Importance of Knowing Different Risk-Associated Phenotypes and Antibodies in Identifying the Correct Underlying Tumor.

Paraneoplastic neurologic syndromes (PNS) are neurologic disorders that can affect any part of the nervous system, occur in association with cancer, and have an immune-mediated mechanism that produces direct damage to the neural tissue. Neurological symptoms frequently precede, in months to years, the symptoms directly attributed to the primary tumor, requiring a high clinical suspicion for adequate investigation. We report the case of a man in his early 80s admitted for an altered level of consciousness, alternating between periods with stupor and drowsiness, short-term waking states and psychomotor agitation, respiratory failure and dysautonomia, resembling a Morvan's syndrome. Anti-leucine-rich glioma-inactivated 1 and anti-contactin-associated protein-like 2 antibodies were both positive and, after exclusion of infectious and autoimmune systemic causes, the possibility of PNS was raised. Screening for the primary tumor was pursued, and an 18F-fluorodeoxyglucose (18F-FDG)/PET showed only an intensely hypermetabolic, apparent parietal thickening of the lower rectum. Due to the frequent association of Morvan's syndrome to thymoma, a review of the CT of the thorax images was requested and a mediastinal image with features of thymoma was identified. PNS treatment and prognosis depend on finding and treating the underlying tumor, with benefits in both resolution of neurological symptoms and in the prognosis of the underlying tumor itself. Therefore, clinicians should be aware of this frequent but underdiagnosed and underreported condition, in order to improve the chances of better outcomes.

Severe Pneumonia Caused by SARS-CoV-2: A Novel Cause of Platypnoea-Orthodeoxia Syndrome.

Platypnoea-orthodeoxia syndrome (POS) is a condition characterized by dyspnoea and hypoxaemia while sitting or standing, which improves during decubitus. It is usually caused by intracardiac right-to-left shunting through a patent foramen ovale but may also occur due to pulmonary ventilation-perfusion mismatch of other aetiologies. A new cause of POS was recently described: SARS-CoV-2 pneumonia. We report the case of a 62-year-old man admitted for SARS-CoV-2 pneumonia with respiratory failure. Chest computed tomography angiography showed pulmonary thromboembolism and parenchymal lung changes compatible with COVID-19. He had worsening dyspnoea in a sitting position, relieved by assuming the dorsal position. He was diagnosed with POS after other causes were excluded. POS is an underdiagnosed complication of COVID-19 and is manageable with respiratory rehabilitation. LEARNING POINTS: Platypnoea-orthodeoxia syndrome is an under-recognized condition presenting as a complication of a structural shunt.We describe SARS-CoV-2 pneumonia as a novel cause for this syndrome.It is a reversible syndrome provided there is early diagnosis and initiation of pulmonary rehabilitation.