Diagnosis
A wide variety of infections can occur in transplant patients. It depends on what the transplant is (bone marrow worse than heart/liver worse than kidney), whether it is early or late after the transplant and what the immunosuppression is (prednisone/cyclosporin worse than other immunosuppression regimens). From a practical point of view, they all act like AIDS patients with CD4 <100.
Epidemiology
I am going to go out on a limb here and suggest getting a transplant. Some infections come in with the transplanted organ, some reactivate in the patient and some are newly acquired as a result of immunosuppression (everything from LCM to Balamuthia). Infections spread by the transplant will allow you to show your sensitivity if you pretend to be a hard-ass like Dr. Cox.
There are a whole host of infections that can be transferred with the new organ and depends on the exposures (Review).
Genetic PTX3 deficiency increases the risk of invasive disease in stem cell transplant (PubMed).
Microbiology
- Polyomavirus urinary shedding is more frequent in the liver (64%) than kidney recipients (39%). JCV was more frequent in liver than kidney recipients (71% vs 38%). BKV is shed more often by kidney transplants (69% vs 52%). Lower CrCl values is significantly associated with JCV shedding in both kidney and liver recipients (PubMed).
- Coronaviral infections are often fatal in this population (PubMed).
- PML: due to the JC virus, it is a white matter brain meltdown.
- Acute Parvovirus B19 can cause pancytopenia and can only be diagnosed with PCR (PubMed).
- Cytomegalovirus: in all patients. Increases the chance of rejection in solid organ transplants and death from pneumonia in bone marrow transplants. Prophylaxis should part of the care. Some polymorphisms in Toll-like receptor 2 can increase the risk of CMV infections (PubMed). In transplant patients, a low absolute lymphocyte count (0.73 ± 0.42 × 103 cells/μL), is strongly associated with CMV reactivation (PubMed).
- Wound infection: usually suspects (streptococcal and S. aureus) but any organism can infect these patients.
- Pneumocystis: especially early, with prednisone and after the anti-thymocyte globulin. It often becomes symptomatic during the steroids wean. These days most patients are on prophylactic trimethoprim/sulfamethoxazole.
- Liver abscess: surprisingly, it is common in liver transplants. It is the usual suspects, although many centers have problems with VRE.
- Toxoplasma: especially in the heart and bone marrow transplants patients. Can reactivate in the transplanted heart.
- Cryptococcus neoformans: meningitis, it may start as pneumonia.
- Listeria monocytogenes: usually meningitis but can present as a febrile nonfocal illness.
- Tularemia from the transplanted organ (PubMed).
- Molds: Aspergillus and Mucormycosis lead the list, lung, and brain are the most commonly involved organs.
- Post Transplant Lymphoproliferative Disease: Ebstein Barr virus caused pseudo-lymphoma, presents with fever and rapidly growing lymph nodes.
- Reactivation of local disease and/or dissemination of Tuberculosis (PubMed), Herpes simplex, Herpes Zoster, Coccidioides immitis, Histoplasma, Penicillium, and Strongyloides stercoralis (both reactivation and from the transplanted organ (PubMed) depending on past exposure history.
Empiric Therapy
Except for sepsis, get the diagnostic tests done before you start empiric therapy. Be invasive if you have to; best outcomes are probably with earlier rather than later, therapy.
Pearls
OKT3 can cause a drug-induced meningitis in the first several days after infusion.
Vancomycin can prevent C. difficile in heme transplant patients (Pubmed).
IRIS can also occur in transplant patients with exacerbations fungi of all types, M. tuberculosis, Cytomegalovirus, and polyomavirus nephropathy.
Rants
Self-serving note: "Infectious disease consultation in recipients of solid organ transplant is associated with increased LOS and hospitalization costs but decreased mortality and reduced rehospitalization rates. Early consultation with infectious disease specialists decreases healthcare resource utilization compared with delayed referrals (PubMed)."
Curious Cases
Relevant links to my Medscape blog
Sorry, nothing to learn here. Keep moving. A content free post.
Last Update: 08/31/19.