CMV Pneumonitis After Heart Transplant
58-year-old man 8 months after orthotopic heart transplant for ischemic cardiomyopathy presents with 5 days of fever, dry cough, and progressive dyspnea. He is on tacrolimus 4 mg BID, mycophenolate mofetil 1,000 mg BID, and prednisone 5 mg daily. Exam: temperature 38.4 C, HR 110, BP 112/70, RR 26, SpO2 90% on 4 L. Chest CT shows diffuse ground-glass opacities; BAL is pending. Labs: WBC 2.1, ANC 800, platelets 90, creatinine 1.3 mg/dL, tacrolimus trough 14 ng/mL. CMV DNA 12,000 IU/mL. Donor CMV positive/recipient negative. He has no rejection history; last biopsy showed 1A.
1. What is the likely diagnosis, and what immediate changes would you make to immunosuppression?
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CMV pneumonitis is the leading diagnosis in a D+/R- heart transplant recipient with fever, hypoxemia, ground-glass opacities, neutropenia, and CMV DNA 12,000 IU/mL. Start IV ganciclovir 5 mg/kg every 12 hours, adjusted for renal function, and hold mycophenolate until the ANC recovers. Lower tacrolimus to a target trough of about 5-8 ng/mL rather than stopping it completely, to preserve some rejection protection. Add CMV IVIG or hyperimmune globulin for severe pneumonitis if available, but do not rely on it alone. Obtain broad diagnostics including BAL for Pneumocystis, fungal, and bacterial infection. Use G-CSF if ANC falls below 500 or if ganciclovir must continue. Avoid valganciclovir in severe GI or pulmonary disease because absorption may be unreliable.
2. How do you balance the risk of rejection against the need to reduce immunosuppression?
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This is a judgment call. The patient has no rejection history and biopsy 1A, so infection control takes priority. I would hold mycophenolate, reduce tacrolimus modestly, and continue low-dose prednisone. I would not stop tacrolimus entirely unless there is life-threatening sepsis or severe leukopenia. Monitor for rejection with symptoms, ECG, echo, and troponin; if fever resolves but new HF or arrhythmia appears, consider endomyocardial biopsy. Once CMV DNA falls and ANC >1,000, restart mycophenolate at a reduced dose and gradually return tacrolimus to maintenance. Coordinate with transplant pharmacy and infectious disease. The goal is to avoid both CMV progression and a rejection episode precipitated by abrupt withdrawal.
3. What prophylaxis should have been used, and what monitoring would you recommend after discharge?
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For a D+/R- heart transplant recipient, CMV prophylaxis with valganciclovir 900 mg daily (renally adjusted) for 6-12 months is standard, with CMV DNA monitoring if prophylaxis is shortened or interrupted. He should also receive Pneumocystis prophylaxis with trimethoprim-sulfamethoxazole, and monitoring for ganciclovir-related myelosuppression. After discharge, check CMV DNA weekly until undetectable, then every 2-4 weeks; monitor CBC, creatinine, and tacrolimus levels. Repeat bronchoscopy if symptoms persist. Educate about fever, dyspnea, and neutropenia. If CMV becomes refractory, test for UL97 and UL54 mutations and consider foscarnet or cidofovir, watching renal toxicity.