(P-330) Drug-drug Interactions in a Kidney Transplant Patient with COVID-19: A Case Report

Background: Transplant patients are highly at risk due to long-term immunosuppressive therapy, and precise treatment approaches are needed to not only cure the disease but also protect graft function.

Objectives: This report describes a kidney transplant patient with COVID-19, also discusses the importance of drug-drug interactions related to COVID-19 treatment protocol medications, especially with immunosuppressants in these patients.

Methods: This patient was admitted to Razi Educational Remedial & Research Center, a teaching hospital Rasht, Iran. During hospitalization, medical records of this patient was examined. Relevant data, including age, gender, vital signs, initial symptoms, physical examination, CT findings, antiviral and immunosupressive regimens and laboratory data including PCR, CRP, CBC, and creatinine level, serum electrolytes, were collected in the collection sheet.

Results: A, a 44-year-old man who underwent a kidney transplantation in 2011, with a baseline Cr of 1.3 mg/dL, was admitted on March 14, 2020. Physical examination on admission revealed a body temperature of 37°C, and oxygen saturation of 96% (ambient air). His chest CT showed consolidation, multifocal and bilateral, bronchiectasis, and a CT score of 16. based on laboratory and clinical characteristics he was diagnosed with COVID-19.The baseline regimen was sirolimus (1mg bd), prednisolone (5mg daily), mycophenolate sodium (720mg bd). Treatment with lopinavir/ritonavir (400mg/100mg bd), along with hydroxychloroquine (400mg stat) and oseltamivir (75mg bd), was started. Adjustments were as follows, sirolimus was reduced to (1mg daily), mycophenolate sodium was discontinued, and hydrocortisone (50mg tds) was also initiated. based on recommendationsand due to m-TOR inhibitors potentials for leukopenia, thrombocytopenia, and pneumonitis, sirolimus was changed to tacrolimus (1mg bd). In the following days, shortness of breath worsened and oxygen saturation dropped to 88% in ambient air; On day 20, tacrolimus level was above 30 ng/dL, so tacrolimus was ceased for six days and was restarted again. A week later, He was discharged with tacrolimus (1mg bd), mycophenolate sodium (360mg bd), and prednisolone (5mg bd). In the follow-up, tacrolimus level was 8 ng/dL, and he was in good health at home.

Conclusions: a decrease in immunosuppressant dose should be measured in critically ill patients. Special consideration is needed for the pharmaceutical interactions between antivirals, and immunosuppressants. Frequent monitoring of CNI and m-TOR inhibitor levels during hospitalization is recommended to determine ideal treatment and prevent serious clinical toxicity.