Posttransplant infections

1. What type of infections do kidney transplant recipients develop?

• Donor-derived infections

• Recipient-derived infections

• Nosocomial-acquired infections

• Community-acquired infections

2. Is there any pattern to infections that occur post transplantation?

Yes. Karuthu et al. reviewed this recently, including the timing of infections post transplant. Infections occur in a generally predictable pattern after kidney transplantation. See Fig. 60.1

• First month post transplant:

  • Nosocomial and surgery-related infections are the predominant infections

  • Aspiration pneumonia

  • Catheter infections

  • Wound infections

  • Anastomotic leaks

  • Clostridium difficile colitis

  • Resistant organisms such as methicillin-resistant Staphylococcus aureus

• Months post transplantation 1 through 6:

  • Activation of latent infections is most common

  • Pneumocystis jiroveci (previously Pneumocystis carinii ) pneumonia

  • Fungal infections

  • Herpes-related disease

  • BK virus

  • Clostridium difficile colitis

  • Hepatitis C virus

  • Adenovirus

  • Influenza

  • C ryptococcus

  • Mycobacterium tuberculosis .

• Posttransplant month 6 and beyond:

  • Community-acquired infections are predominant (urinary tract infections [UTIs], pneumonia)

  • Fungal infections, including Nocardia, Aspergillus, and Mucor

  • Late viral infections (cytomegalovirus [CMV], hepatitis B and C, herpes simplex virus, John Cunningham (JC) virus)

3. What is the most common bacterial infection that leads to hospitalizations in kidney transplant patients?

UTIs. The most common bacterial cause is Escherichia coli .

4. What infectious prophylaxis do patients receive post transplant?

• Valganciclovir to prevent CMV for 3 to 6 months

• Trimethoprim-sulfamethoxazole to prevent Pneumocystis jirovici and UTIs for 6 months

• Nystatin or clotrimazole to prevent esophageal candidiasis for 3 months

5. What is BK virus?

BK virus is a ubiquitous, double-stranded DNA polyomavirus with a 5300–base pair genome that replicates in the host nucleus. The polyoma family includes JC virus (infectious cause of progressive multifocal leukoencephalopathy [PML]), SV40, and monkey polyomavirus. Although the human polyomaviruses are highly seroprevalent in humans, they appear to cause clinical disease only in immunocompromised hosts.

6. What is BK-associated nephropathy?

BK virus damages the transplant kidney. The prevalence of BK nephropathy ranges from 1% to 10%. BK nephropathy is characterized by a tubulointerstitial disease pattern that closely resembles acute rejection.

7. Besides nephropathy, can BK virus cause any other kidney problems?

Yes. BK virus is associated with ureteral stenosis/strictures, which may lead to obstructive uropathy. Obstructions associated with BK virus usually occurs 2 to 4 months post transplant, whereas ischemia-induced stenosis usually occurs 1 to 2 weeks postoperatively.

8. What are the risk factors for the development of BK-associated nephropathy?

• Human leukocyte antigen mismatch

• Previous acute rejection

• Use of lymphocyte depleting therapy

• Use of steroid pulses

• Age >55

• Male gender

• White race

• Diabetes