He enjoys international recognition as an authority on the basic biology and medical significance of atypical bacterial organisms and is considered a pioneer and an expert on the role of these unusual bacteria in the persistence and expression of kidney and urological infectious diseases.
He first became interested in the role of atypical bacterial forms after noting that a large number of patients with urinary tract infections suffer from continual relapsing illness.
After applying these data to the human condition, Domingue reasoned that in some patients who suffer from chronic bacterial infections, the disease process could be related to the fact that bacteria are able to differentiate into the resistant electron dense bodies that he observed in tissue cultures.
[5] In 1974, he and his graduate student, Mary Green, along with Paul Heidger, a faculty collaborator, published two landmark companion papers in the journal Infection and Immunity.
"[5] He went on to conclude, "Bacteriologic advances, which include special culture media and stains, electron microscopy and molecular techniques such as PCR (polymerase chain reaction), have revealed an increasing number of previously unidentifiable organisms in a variety of pathological conditions.
He delivered many invited international and national lectures about bacterial persistence and expression of disease and wrote a book on the subject, Cell Wall-Deficient Bacteria: Basic Principles and Clinical Significance.
[11][12] He studied the immunological consequences of a vasectomy, as well as the role of various gram negative pathogens in the host-pathogen interaction in pyelonephritis, and the effects of antibiotics and chemotherapy on urinary tract infections.