Clinical and epidemiological significance of isolated cultures of Koch bacillus after conclusion of chemotherapy

: In a group of 33 patients from the Gorj, Dolj and Mehedinţi Districts positive cultures of Koch bacilli were found after various intervals following the end of chemotherapy. These positive cultures were found after negative cultures were obtained repeatedly during the usual bacteriological monitoring. The "isolated" positive culture was obtained after an interval of 11,7 +/- 8,1 months after the end of the treatment. The average number of colonies in each tube was of 3,8 +/- 3, in most of the cases (63%) there were 1--2 colonies in each tube, and in only 27% there were more than 4 colonies per tube. The development of the germs was slow and the colonies were noted 32 +/- 14 days after seeding in the Lowenstein medium. All the cases have been followed, bacteriologically as well as radiologically on the average for 16 +/- 10,9 months. Chemotherapy was not taken up again in this period. In 2 cases a new positive culture was found, and these patients were considered to have recidives, and were treated again. Of the 26 contacts under the age of 20 years 5 remained uninfected at the end of the cure and did not display allergy during the period of surveillance. None of the allergic contacts developed the disease. It is concluded that after a correct therapy the development of positive cultures during bacteriological surveillance, especially if only few colonies are noted, does not means that there is a recidive, making mandatory the sustained repetition of the bacteriological investigation without taking up again the chemotherapy.