instruction: what specimen test was first given until 08/2105 to patient 10686?
response: SELECT microbiologyevents.spec_type_desc FROM microbiologyevents WHERE microbiologyevents.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 10686) AND STRFTIME('%y-%m', microbiologyevents.charttime) <= '2105-08' ORDER BY microbiologyevents.charttime LIMIT 1