Infections after hematopoietic stem cell transplantation

Timeline of Infections

Time	Risk factors	Bacteria	Viruses	Fungi	Parasites
Pre-engraftment day 0 to 30	Neutropenia, mucositis, and central lines	GPCs and GNBs	BK virus, HSV, and resp/enteric viruses	Candida and Aspergillus	Strongyloides
Early post-engraftment to day 100	Immunosuppressing meds, acute GVHD, central lines	GPCs, encapsulated bacteria, Listeria, Salmonella, Nocardia	HSV, CMV, HHV-6, adenovirus, resp/enteric viruses	Aspergillus, other molds, PJP	Strongyloides, Toxoplasma
Mid post-engraftment to 1 year	Immunosuppressing meds, chronic GVHD	Encapsulated bacteria, Listeria, Salmonella, Nocardia	VZV, EBV (and PTLD), CMV, respiratory/enteric viruses	Aspergillus, other molds, PJP
Late post-engraftment after 1 year	Immunosuppresing meds, chronic GVHD	Encapsulated bacteria, Listeria, Salmonella, Nocardia	VZV, CMV, respiratory/enteric viruses

Prevention

Infection	Preventing exposure	Preventing disease
Bacterial infections
Early disease (0-100 days after HCT)		Use levofloxacin or other respiratory fluoroquinolone in adult patients with anticipated neutropenia of 7 or more days until recovery of neutropenia. GM-CSF or G-CSF may decrease risk of infection, but unclear if it decreases mortality.
Late disease (100 days after HCT)		Antibiotic prophylaxis is indicated for alloHSCT recipients with chronic GVHD to prevent invasive pneumococcal disease until cGVHD resolves.
CLABSI	Implement a CLABSI bundle to ensure maximum sterility on insertion.	If infection rate is still >1 per 1000 catheter days, can consider prophylactic minocycline plus rifampin.
Streptococcus pneumoniae	Routine precautions.	Immunization for all HCT recipients. Antibiotic prophylaxis for chronic GVHD and for low IgG levels, regardless of vaccination status, usually with penicillin.
Viridans group streptococci		Pre-conditioning dental consults.
Haemophilus influenzae type b	Ensuring up-to-date immunizations of close contacts.	Immunization of all HCT recipients. Post-exposure prophylaxis if exposed.
Bordatella pertussis	Ensuring up-to-date immunizations of close contacts.	Immunization of all HCT recipients. Post-exposure prophylaxis if exposed.
Viral infections
Cytomegalovirus	Pre-transplant screening of donor and recipient serostatus.	All R+ or D+ recipients should have either prophylaxis or close monitoring with preemptive treatment until at least day 100. Monitoring should start on day 10 and continue weekly until at least day 100.
Epstein-Barr virus, especially PTLD	Pre-transplant screening of donor and recipient serostatus, especially in children.	Monitor high-risk recipients (T-cell depletion, ant-T-cell antibodies, umbilical cord transplants, and haplo-identical transplants), with reduction in immunosuppression if rising viral load.

Further Reading

• Life-threatening Infection in Transplant Recipients. Crit Care Clin. 2013 Oct;29(4):953-73. doi: 10.1016/j.ccc.2013.06.012