Episode 414: 421. Scabies and DUKE criteria

Stavropoulou E, et al. Reassessing the 2023 International Society for Cardiovascular Infectious Diseases Duke clinical criteria for infective endocarditis: Impact of excluding fever and updating diagnostic definitions. Clin Infect Dis 2025 Dec 31; [e-pub]. DOI: 10.1093/cid/ciaf737.  Big takeaways About 35% of patients truly had IE. Fever showed up in 80% of patients both with and without IE, so it did not help distinguish them. Dropping fever from the criteria actually made them better:   Sensitivity improved: 77% (no-fever) vs 74% (standard). Specificity improved a lot: 80% vs 49%. "Possible IE" shrank from 39% to 17%, meaning fewer gray-zone cases. Only 0.4% of patients without IE were incorrectly labeled as having IE.  Both are widely used and both can work for regular (non-crusted) scabies. The SCRATCH trial: who won?In the SCRATCH trial from France, researchers treated about 1000 people in 300 households with confirmed scabies. Each household was randomized to: Whole-body 5% permethrin cream on days 0 and 10, orOral ivermectin (weight-based) on days 0 and 10.They then checked who was cured at day 28. Here's what they found:Household cure ratesPermethrin: 88% curedIvermectin: 72% curedTranslation: For every 6 households treated with permethrin instead of ivermectin, one extra household was fully cured (NNT  6). Index (main) patient cure ratesPermethrin: 92%Ivermectin: 77%That's one extra person cured for about every 7 treated with permethrin instead of ivermectin (NNT  7). Side effectSkin irritation-type reactions: 14% with permethrin vs 10% with ivermectin.So permethrin wins on cure, with a small trade-off in local skin reactions.