Interleukin-2 receptor alpha-subunit deficiency and spontaneous perforation secondary to cytomegalovirus (CMV) colitis

The authors present the difficulties of diagnosis and treatment of a 9-year-old girl with IL-2 receptor alpha-subunit (IL-2Rα) deficiency -a rare type of severe combined immunodeficiency (ID)- causing severe complications.

She was born of an uneventful dizygotic twin pregnancy and had only mild infections in early childhood. Her female co-twin is healthy. At 5 years of age autoimmune haemolytic anaemia was diagnosed; corticosteroids (CS) were given which could be tapered soon. In the following years while she was on low-dose CS every other day she had only mild infections and two haemolytic crises, the latter treated with pulse CS.

At the age of 9 she went through Candida and Salmonella enteritis. A month later ulcerative skin lesions, recurrent fever and loose stools necessitated hospital admission. On the second day her condition deteriorated and she developed multiple putamen infarctions. All bacterial cultures and serologic and thrombophilia tests were negative. Imaging studies showed thickened small bowel loops and splenomegaly. Colonoscopy and histology suggested Crohn's disease although granulomata could not be seen. CS and mesalazine were started and her condition improved. At this stage immunology work-up suggested common variable ID and she was given regular immunoglobulin (Ig) substitution.

Two months after initial evaluation she developed spontaneous perforation of the ascending colon requiring right hemicolectomy. CS was stopped at once. Histology showed severe CMV infection and ulcerative inflammation. Extended immunology investigations revealed IL-2Rα deficiency. After gancyclovir therapy control colonoscopy and histology showed remission and the CMV antigenaemia has resolved. She became free of symptoms on regular Ig substitution. Unfortunately, she developed graft-versus host disease and died after bone-marrow transplantation.

Both IL-2Rα deficiency and CMV colitis in non-AIDS or transplanted patients are rare conditions. In this case ID and transfusions lead to acquisition of CMV infection which caused Crohn's disease-like bowel inflammation and vasculitis.