Late-Onset CMV After Interrupted Prophylaxis
A 50-year-old man underwent liver transplantation for primary sclerosing cholangitis 10 weeks ago. He is CMV-seronegative and received a liver from a CMV-seropositive donor. He was started on valganciclovir prophylaxis but stopped it 3 weeks ago because of neutropenia (absolute neutrophil count 700/µL). He now presents with fever, fatigue, watery diarrhea, and oral candidiasis. Laboratory tests: ALT 120 U/L, AST 95 U/L, total bilirubin 1.0 mg/dL, alkaline phosphatase 140 U/L, WBC 2,100/µL, ANC 600/µL, platelets 90,000/µL, and CMV DNA 12,000 IU/mL. Tacrolimus trough is 9 ng/mL; mycophenolate mofetil is 500 mg twice daily. He is hemodynamically stable. Stool studies for bacteria and parasites are negative. Ultrasound shows patent hepatic artery and no biliary dilatation.
1. What is your diagnostic assessment, and what studies would you obtain to determine whether this is CMV syndrome or tissue-invasive disease?
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This is a high-risk CMV mismatch (D+/R-) with interrupted prophylaxis, fever, leukopenia, transaminitis, and diarrhea. The CMV DNA level confirms active replication, but it does not by itself distinguish CMV syndrome from tissue-invasive disease. CMV syndrome includes fever, malaise, leukopenia, thrombocytopenia, and transaminitis without end-organ damage. Tissue-invasive disease requires documentation of CMV in tissue: colitis would show ulcers and positive immunohistochemistry on endoscopic biopsy; hepatitis would require liver biopsy. I would obtain endoscopy with biopsy because of diarrhea, check ophthalmologic symptoms, and send stool for C. difficile and other pathogens. I would also monitor renal function before dosing antivirals.
2. How would you treat him, including antiviral dosing and immunosuppression adjustments?
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Treat with IV ganciclovir 5 mg/kg every 12 hours, adjusted for renal function. Oral valganciclovir is an alternative only if the patient is absorbing and disease is mild; this patient has diarrhea and significant symptoms, so IV therapy is preferred initially. Because of neutropenia, stop mycophenolate and consider granulocyte colony-stimulating factor. Maintain tacrolimus but avoid overimmunosuppression; do not stop all immunosuppression abruptly. If there is no response or worsening, consider foscarnet or cidofovir with careful renal monitoring and send resistance testing. CMV hyperimmune globulin is not routine. Treat oral candidiasis and evaluate for other opportunistic infections.
3. What monitoring and prevention strategies are needed after treatment?
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Follow CMV DNA weekly until it is undetectable and symptoms resolve, then every 2-4 weeks for several months. Treatment should continue until clinical resolution and at least one or two negative DNA tests. After treatment, consider secondary prophylaxis with valganciclovir while immunosuppression remains intense, especially if mycophenolate is restarted. Monitor for relapse, retinitis, colitis, and hepatitis. Reintroduce mycophenolate cautiously with blood count monitoring. Educate the patient about adherence and report fever or diarrhea. Long-term, the goal is to reduce immunosuppression to the lowest effective level and prevent late CMV disease.