Intravascular large cell B lymphoma presenting as central nervous system pseudo-vasculitis: A rare diagnostic challenge.

Intravascular large B cell lymphoma (IVLBCL) is a very rare subtype of aggressive non-Hodgkin B cell lymphoma characterized by intravascular proliferation of clonal B lymphocytes, classically associated with pulmonary and cutaneous disease and, less frequently, with central nervous system (CNS) involvement. Brain imaging findings are usually non-specific, with evidence of multiple vascular occlusions and stroke as non-specific multifocal abnormalities. We present an exceptionally rare case of IVLBCL in a patient with unexplained inflammatory syndrome with B symptoms and rapidly progressive neurological impairment, with multifocal hemorrhagic and tumefactive brain lesions seen on MRI. We suggest that in this clinical setting, the presence of tumefactive and hemorrhagic lesions should raise suspicion for IVLBCL and lead to the decision to perform a biopsy, which, nonetheless, remains the diagnostic gold standard.

Carnitine Deficiency after Long-Term Continuous Renal Replacement Therapy.

A 60-year-old man was admitted in the intensive care unit (ICU) for a rapidly progressive respiratory failure due to SARS-CoV-2 infection. He developed numerous complications including acute kidney injury (AKI) requiring prolonged continuous renal replacement therapy (CRRT). Enteral feeding was initiated on day 8. Despite nutritional management, there was a remarkable amyotrophy and weight loss. On day 85 in the ICU, the patient became progressively unresponsive. An extensive metabolic workup was performed, and blood results showed hyperammoniemia and hypertriglyceridemia. Plasma free carnitine level was low, as was also copper. After carnitine supplementation, the neurological condition rapidly improved, and metabolic perturbations regressed. Prolonged CRRT may be complicated by clinically significant deficiency in micronutrients and trace elements.