Can someone help me please?

Question

A 45 year-old woman complaining of breast pain was diagnosed with having HER2-positive breast cancer. The patient underwent lumpectomy followed by a period of chemotherapy including adjuvant treatment. Over the course of their treatment, the patient developed a urinary tract infection that required antimicrobial therapy, which initially consisted of a trimethoprim/sulfametoxazole combination drug. However, the patient during the course of her therapy suffered multiple recurrent infections and was, consequently, enrolled in a clinical trial to test the efficacy of a new mannoside anti-infective agent.

Question: Discuss the roles of the three components of the patient’s treatment for her relapsing UPEC infection. Your discussion should include the pertinent virulence factors that contribute to the establishment of the infection and the initial treatment failure.

Answer 1

Hi Elena,

This is a tough question! To answer, try to think about the ways these drugs work in controlling bacterial growth. Both are bacteriostatic, meaning they don't directly kill bacteria, only halt their growth. In a normal individual this is sufficient because the immune system can then rid the body of this infection. What's different about this patient? What does the cancer and chemotherapy do to the immune system?

Lastly, think about the constant use of antibiotics to treat infection in this patient. What pressure does this put on the microorganism. It selects those individuals that can withstand the treatment and leads to growth of a resistant population. Also remember that many of the virulence factors are on mobile genetic elements, such as plasmids. This all leads to a selection of the best "survivor" for this particular environment.