His removal to the U.S. in 1891 was doubtless prompted by a winter's exile, imposed upon him and several fellow-students because of their participation in a debate which did not meet with the approval of the local authorities.
Even in the earlier days of his medical career, as a struggling young practitioner endeavoring to gain a foothold, he saw how conditions were with reference to tuberculosis in Chicago at that time, and he could not refrain from doing something to help.
At no little sacrifice and expense, he personally made an investigation of the prevalence of tuberculosis in some of the crowded quarters of the city, particularly in the districts where the Jewish population was in evidence.
These studies, among the first of their kind, gave Sachs considerable prominence at the Sixth International Congress on Tuberculosis in 1908, and won for him special honorable mention from the jury of awards.
It was largely due to Sachs' influence that Mrs. Keith Spalding donated the funds for the Edward Sanatorium at Naperville, of which institution he became the director and physician in chief.
The body of Sachs was interred on the grounds of the Naperville Sanatorium, and on the memorial tablet indicating the site, is the following inscription: In Memory of DR. THEODORE B. SACHS, whose life was spent in disinterested efforts to relieve the condition of the unfortunate, never indifferent to the distress of others, he labored unselfishly and untiringly in their behalf, and this Sanatorium in which ground he sleeps is a monument to his unusual greatness of heart and singleness of purpose.