biostudies-literatureUnknown12(9)Hayashi M<h4>Background</h4>Optimal timing for treatment initiation in <i>Mycobacterium avium</i> complex pulmonary disease (MAC-PD) remains unclear due to lack of established rules for predicting treatment response.<h4>Methods</h4>A retrospective observational study was conducted to develop a prediction model for treatment failure at 2 Japanese university hospitals between 2012 and 2023. Participants were 135 patients with MAC-PD who received macrolides and ethambutol-containing regimens over 1 year. Treatment failure was defined as nonachievement culture conversion at 1 year. We selected model components as cavity (categorized by diameter) and bronchiectasis (categorized by modified Reiff score) on pretreatment computed tomography. Their combinations of each category were scored based on number oOpen forum infectious diseasesofaf565https://www.ebi.ac.uk/biostudies/studies/S-EPMC12465108biostudies-literatureDeveloping a Simple Scoring System on CT Findings for Predicting Treatment Failure in &lt;i&gt;Mycobacterium avium&lt;/i&gt; Complex Pulmonary Disease: The BCD (Bronchiectasis and Cavity Distribution) Score.PMC12465108Matsukura SCho HYokoe TTakishima HYamaguchi FHayashi MfalseDeveloping a Simple Scoring System on CT Findings for Predicting Treatment Failure in &lt;i&gt;Mycobacterium avium&lt;/i&gt; Complex Pulmonary Disease: The BCD (Bronchiectasis and Cavity Distribution) Score.<h4>Background</h4>Optimal timing for treatment initiation in <i>Mycobacterium avium</i> complex pulmonary disease (MAC-PD) remains unclear due to lack of established rules for predicting treatment response.<h4>Methods</h4>A retrospective observational study was conducted to develop a prediction model for treatment failure at 2 Japanese university hospitals between 2012 and 2023. Participants were 135 patients with MAC-PD who received macrolides and ethambutol-containing regimens over 1 year. Treatment failure was defined as nonachievement culture conversion at 1 year. We selected model components as cavity (categorized by diameter) and bronchiectasis (categorized by modified Reiff score) on pretreatment computed tomography. Their combinations of each category were scored based on number o2025-01-01T00:00:00Z2025 Sep2026-06-03T21:41:11.319Z2026-05-02T03:08:14.24ZS-EPMC124651084101870610.1093/ofid/ofaf565