Hi ! Good morning. I am Dr Shareef answering your query. 1) The cause of the growth is due to infection of your urogenital tract with this bacteria. 2) The mode of contraction is usually by sexual activity. 3 & 4) Though it is not a serious infection, it has to be treated to avoid its complications like a recurrent UTI, a possible effect on fertility by its effect on the quality of sperms in the semen 5) You can take any of the drug to which the organism is most sensitive to as per the sensitivity report. 6) The infection in the semen means an infection in the prostate, and as the antibiotic reaches the site less effectively, you may have to take the antibiotic for a longer time, say about 3-4 weeks in consultation with your treating doctor. 7) As these are all prescription drugs, and the dose depends on for what condition the test was performed along with the condition of your kidney function, the dose can only be decided by your treating family physician. 8) You can get the test repeated at least 72 hrs after completing your course of antibiotics. Thanks for consulting healthcaremagic for your health query. Wishing you a quick recovery. Dr Shareef.