Melatonin in the Prophylaxis of SARS-CoV-2 Infection in Healthcare Workers (MeCOVID): A Randomised Clinical Trial.

We evaluated in this randomised, double-blind clinical trial the efficacy of melatonin as a prophylactic treatment for prevention of SARS-CoV-2 infection among healthcare workers at high risk of SARS-CoV-2 exposure. Healthcare workers fulfilling inclusion criteria were recruited in five hospitals in Spain and were randomised 1:1 to receive melatonin 2 mg administered orally for 12 weeks or placebo. The main outcome was the number of SARS-CoV-2 infections. A total of 344 volunteers were screened, and 314 were randomised: 151 to placebo and 163 to melatonin; 308 received the study treatment (148 placebo; 160 melatonin). We detected 13 SARS-CoV-2 infections, 2.6% in the placebo arm and 5.5% in the melatonin arm (p = 0.200). A total of 294 adverse events were detected in 127 participants (139 in placebo; 155 in melatonin). We found a statistically significant difference in the incidence of adverse events related to treatment: 43 in the placebo arm and 67 in the melatonin arm (p = 0.040), and in the number of participants suffering from somnolence related to treatment: 8.8% (n = 14) in the melatonin versus 1.4% (n = 2) in the placebo arm (p = 0.008). No severe adverse events related to treatment were reported. We cannot confirm our hypothesis that administration of melatonin prevents the development of SARS-CoV-2 infection in healthcare workers.

Bronchial involvement in the cramp-fasciculation syndrome.

BACKGROUND/AIMS: Cramp-fasciculation syndrome (CFS) is an acquired, chronic, usually benign and rather heterogeneous condition with isolated fasciculations and muscle cramps generally induced by physical exercise. They commonly involve calf and quadriceps muscles. The pathophysiology of CFS is related to peripheral nerve hyperexcitability, most often located at the motor nerve terminal or intramuscular arborization. METHODS: A 21-year-old man presented with a progressive syndrome of bronchospasm, cramps and muscle twitches related to physical exercise. Spirography showed bronchial hyperresponsiveness, so he received inhaled corticosteroids and beta2-agonists that improved respiratory symptoms. Electrodiagnostic studies were consistent with CFS. Gabapentin was then introduced. RESULTS: Both respiratory and muscle symptoms improved. A new spirogram after all inhaled medication had been discontinued was normal. CONCLUSION: This picture suggests a concomitant involvement of the peripheral motor nerves of both skeletal and airway autonomic smooth muscle, a presentation not previously reported in CFS.