BALANCING GVHD IMMUNOSUPPRESSION AND COVID19 VIRAL REACTIVATION IN A PATIENT WITH ATYPICAL COMPLETE DIGEORGE SYNDROME

INTRODUCTION: Complete DiGeorge syndrome (DGS) accounts for less than 1% of patients with DGS, with atypical DGS being even rarer. We present a patient with atypical complete DGS who developed autoimmune phenomena attributed to autologous GVHD, and subsequent prolonged respiratory failure due to COVID19 pneumonia while on immunosuppression. CASE DESCRIPTION: A 3-year old male infant of a diabetic mother with complete DGS awaiting thymic transplantation, hypoparathyroidism, hypogammaglobulinemia on IVIG, and recent asymptomatic COVID19 infection was admitted for AKI, electrolyte disarray secondary to malabsorption, and warm autoimmune hemolytic anemia. A month prior he had a persistent eczematous rash, chronic cough, recurrent diarrhea, and thinning hair. Labs revealed uptrending total IgE to 10,000 IU/ml, no eosinophilia, an oligoclonal population of gamma-delta T cells, and increased numbers of CD4+ and CD8+ lymphocytes, which were primarily CD45RO+ central memory T cells. A large portion were activated and expressed HLA-DR. Mitogen proliferation was normal. Given these findings, he was diagnosed with autologous GVHD secondary to autoreactive oligoclonal T cells, and subsequently, atypical complete DGS. Tacrolimus and methylprednisolone were started for immunosuppression. IgE and CD3+ T cells decreased on immunosuppression, but he developed hypoxemic respiratory failure with prolonged intubation due to COVID19 pneumonia. Immunosuppression was gradually weaned. IgE and CD3+ cells increased slightly, but he showed no clinical signs of GVHD and was discharged home after a 3.5 month hospital stay. DISCUSSION: This case highlights the difficult balance between immunosuppression and viral reactivation. After starting immunosuppression for treatment of GVHD, he developed severe COVID19 pneumonia.