Approach to diarrhea in hematopoietic stem cell transplant recipients

Area of Science:

• Infectious Diseases
• Hematology
• Molecular Diagnostics

Background:

• Diarrhea is a common and complex complication in hematopoietic stem cell transplant (HSCT) recipients.
• Etiologies are diverse, including mucosal injury and opportunistic infections, necessitating accurate diagnostics.

Purpose of the Study:

• To review the utility of multiplex PCR-based gastrointestinal diagnostics for infectious diarrhea in HSCT recipients.
• To present a framework for evaluating infectious diarrhea tailored to transplant phases.

Main Methods:

• Review of current literature on multiplex PCR gastrointestinal panels in HSCT.
• Analysis of pathogen distribution across different transplant phases.

Main Results:

• Multiplex PCR panels offer improved sensitivity and faster turnaround times for detecting bacterial, viral, and protozoal pathogens.
• These assays have identified previously underdiagnosed infections but cannot distinguish colonization from infection and may exclude certain pathogens (e.g., Strongyloides stercoralis, cytomegalovirus).
• Pathogen prevalence varies significantly with the transplant phase, highlighting the need for phase-specific diagnostic approaches.

Conclusions:

• Syndromic PCR diagnostics enhance the evaluation of infectious diarrhea in HSCT patients.
• Interpreting results within the context of transplant phase, immune status, and clinical presentation guides timely and targeted management.
• Non-infectious causes and specific pathogens require additional investigation for comprehensive diagnosis.