Introduction 

The human gut contains a diverse range of bacteria which have many varied functions. The functions include maintaining a healthy gut immune system and killing harmful microorganisms.

Allogeneic hematopoietic stem cell transplant (HSCT) involves use of high dose chemotherapy and radiotherapy which damages the gut tissue and predisposes patients to infections and gut graft versus host disease.

A significant proportion of allogeneic HSCT patients will develop bacterial infections which leads to prolonged hospital stay and sometimes death. There is a worldwide rise in infections with multidrug resistant organisms. This is particularly a problem of our country where we have seen a steady rise in multidrug resistant organism infections.

There is a need to minimize the upfront use of higher antibiotics in all HSCT patients to restrict the development of antibiotic resistance.   

What is the rationale of this trial?

In our unit we send stool surveillance cultures in all our patients undergoing allogeneic HSCT weekly. Antibiotic strategy during the episode of fever in pre-engraftment period in HSCT patients can be of two type i.e. empirical or based on the pretransplant surveillance stool cultures.

Empirical strategy is defined, in context, as giving an initial empirical regimen (e.g. cefeperazone and aminoglycoside, or single agent piperacillin-tazobactam) that covers most sensitive organisms. If the fever persists or if the patient deteriorates, or a resistant pathogen is isolated, therapy is ‘escalated’ to an antibiotic or a combination with a broader spectrum. On the contrary, the second strategy employs antibiotics based on the surveillance cultures.

We would like to study the stool colonization patterns in our patients undergoing allogeneic HSCT and the impact of using empirical versus stool guided antibiotic policy on the fever episodes of these patients.

We would also like to study the pattern of stool sensitivity in our HSCT patients over the last 13 years to better understand the emergence of multi drug resistant organisms.

With the above-mentioned facts and hypothesis, we propose a retrospective analysis of all the allogenic hematopoietic stem cell transplants done at our centre from January 2008 to December 2020, analyzing the Pattern of sensitivity and resistance of stool surveillance over 13 years in a tertiary cancer centre and impact of stool surveillance guided selection of antibiotics during neutropenic sepsis in patients undergoing allogeneic HSCT.