the number of patients who had a blood culture ( myco/f lytic bottle) microbiological test in 2105.
select count( distinct admissions.subject_id ) from admissions where admissions.hadm_id in ( select microbiologyevents.hadm_id from microbiologyevents where microbiologyevents.spec_type_desc = 'blood culture ( myco/f lytic bottle)' and strftime('%y',microbiologyevents.charttime) = '2105' )