40th ANNUAL MEETING OF THE EUROPEAN SOCIETY FOR PAEDIATRIC INFECTIOUS DISEASES (ESPID), Athens, Greece, 9 - 13 May 2022, vol.1, no.97, pp.97
Adenosine deaminase (ADA) deficiency is an inherited disorder that damages the immune system and causes severe combined immunodeficiency (SCID). Cases with variable age of onset, severity of symptoms and prognosis have been reported due to the wide clinical and mutation spectrum. Here, an 11-month-old ADA deficiency case presenting with respiratory distress, prolonged diarrhea and severe lymphopenia.
An 11-month-old male patient presented with fever, cough and vomiting. It was learned from his story that, these complaints had been occurring for about 2 days and were gradually increasing. On physical examination, tachypnea, respiratory distress and decreased turgor tone. In laboratory tests, hemoglobin 11.9 g/dL, leukocyte 7290/mm3 (neutrophil 5840/mm3, lymphocyte 470/mm3), platelet 348,000/mm3, C-reactive protein 4.9 mg/L (0-5). Oxygen support, hydration and methylprednisolone treatment were started. In the follow-up, diarrhea was started 8-10 times a day, fluid-electrolyte support and probiotic treatment were began. However, diarrhea continued for about 2 weeks. The patient with prolonged diarrhea, growth retardation and resistant lymphopenia was consulted to the pediatric immunology department for immune deficiency. ADA enzyme level was studied with low CD4-T lymphocyte and lymphopenia. Enzyme replacement therapy was initiated for the patient whose deoxyadenosine level was 6.66 µmol/l (<0.1) and a heterozygous mutation in the ADA gene for p.Y97x(c.290dup) and pY290H(c.868>C). His respiratory distress regressed and he was referred to another health institution for bone marrow transplantation.
ADA deficiency is one of the severe combined immunodeficiencies and may present with different clinical findings depending on the degree of enzyme deficiency. Immunodeficiencies should be kept in mind especially in patients with deep lymphopenia, growth-development retardation and a history of resistant infection.