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Published on: November 8, 2015
Cryptosporidium enteritis in solid organ transplant recipients: multicenter retrospective evaluation of 10 cases
H Bonatti1, L F Barroso, R G Sawyer
1Department of Surgery, University of Virginia Health System, Charlottesville, Virginia, USA.
Background:
Cryptosporidial enteritis, a diarrheal infection of the small intestine caused by the apicomplexan protozoa Cryptosporidium, is infrequently recognized in transplant recipients from developed countries.
Methods:
A retrospective review of all cases of cryptosporidiosis in solid organ transplant (SOT) recipients at 2 centers from January 2001 to October 2010 was performed and compared with transplant recipients with community-onset Clostridium difficile infection (CDI). A literature search was performed with regard to reported cases of cryptosporidiosis in SOT recipients.
Results:
Eight renal, 1 liver, and 1 lung transplant recipient were diagnosed with cryptosporidiosis at median 46.0 months (interquartile range [IQR] 25.2-62.8) following SOT. Symptoms existed for a median 14 days (IQR 10.5-14.8) before diagnosis. For the 9 patients receiving tacrolimus (TAC), mean TAC levels increased from 6.3 ± 1.1 to 21.3 ± 9.2 ng/mL (P = 0.0007) and median serum creatinine increased temporarily from 1.3 (IQR 1.1-1.7) to 2.4 (IQR 2.0-4.6) mg/dL (P = 0.008). By comparison, 8 SOT recipients (6 kidney, 2 liver) hospitalized with community-onset CDI had a mean TAC level of 10.8 ± 2.8 ng/dL during disease compared with 9.2 ± 2.3 ng/mL at baseline (P = 0.07) and had no change in median creatinine. All patients recovered from Cryptosporidium enteritis after receiving various chemotherapeutic regimens.
Conclusions:
Cryptosporidiosis should be recognized as an important cause of diarrhea after SOT and is associated with elevated TAC levels and acute kidney injury. Increased TAC levels may reflect altered drug metabolism in the small intestine.
Insights
Cryptosporidiosis is an important cause of diarrhea in solid organ transplant (SOT) recipients, often linked to increased tacrolimus (TAC) levels and acute kidney injury. Early recognition and treatment are crucial for patient recovery.
Area of Science:
- Infectious Diseases
- Transplant Medicine
- Nephrology
Background:
- Cryptosporidial enteritis, caused by Cryptosporidium, is rarely diagnosed in transplant recipients in developed nations.
- Diarrheal infections post-transplant require careful evaluation to identify causative agents.
Purpose of the Study:
- To investigate the occurrence and clinical characteristics of cryptosporidiosis in solid organ transplant (SOT) recipients.
- To compare cryptosporidiosis cases with Clostridium difficile infection (CDI) in SOT recipients.
- To identify potential associations between cryptosporidiosis, tacrolimus (TAC) levels, and kidney function.
Main Methods:
- Retrospective review of SOT recipients diagnosed with cryptosporidiosis at two centers (2001-2010).
- Comparison with SOT recipients experiencing community-onset CDI.
- Literature search for reported cryptosporidiosis cases in SOT recipients.
Main Results:
- Eight renal, one liver, and one lung transplant recipient were diagnosed with cryptosporidiosis.
- Patients on tacrolimus (TAC) showed significantly increased TAC levels and temporary acute kidney injury.
- Solid organ transplant recipients with CDI did not exhibit similar changes in TAC levels or creatinine.
Conclusions:
- Cryptosporidiosis is a significant cause of post-SOT diarrhea.
- Elevated TAC levels and acute kidney injury are associated with cryptosporidiosis in SOT recipients.
- Altered drug metabolism in the small intestine may explain increased TAC levels.
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