Características del líquido cefalorraquídeo y de las pruebas moleculares en neuroinfección por Listeria monocytogenes

Introduction: Listeria monocytogenes is an intracellular gram-positive bacillus that causes infections in humans, particularly in immunocompromised individuals. It is a food-borne infection via ingestion of contaminated unproperly processed food and may present as a self-limited gastrointestinal infection or as an invasive listeriosis with bacteriemia, neurolisteriosis and maternal-neonatal infection. Diagnosis is typically based on cytochemical tests and cultures however, molecular tests have demonstrated high sensitivity and specificity, which optimizes diagnostic turnaround times and minimizes false-negative rates. Clinical Case: A 77-year-old man with an 18-hour history of severe headache, impaired consciousness and fever. Somnolence and neck stiffness were evidenced in physical examination. Blood tests showed elevated acute phase reactants and cloudy cerebrospinal fluid (CSF) with elevated leukocytes and protein levels and normal glucose levels. Blood cultures and molecular tests confirmed the presence and growth of Listeria monocytogenes. Patient´s outcome was favorable following targeted antibiotic therapy. Discussion and conclusions: this is a potentially serious disease, transmitted via the gastrointestinal tract by consuming contaminated food which can progress to an invasive form. CSF analysis showing normal glucose, pleocytosis and high protein, may be a key pattern guiding initial approach and diagnosis. Molecular tests have proven valuable for confirming the infection.