Methods: Retrospectively reviewed laboratory and clinical data
Results: MAF, 8 year-old male, born to non-consanguineous parents, was a previously healthy boy until 15 months of age when he was diagnosed with juvenile xanthogranulomatosis, with spontaneous remission in 6 weeks. From 17 months to 4 years of age he had 3 pneumonias with pleural effusion and 15 episodes of viral and/or bacterial "bronchitis"(Haemophilus influenzae was isolated once). At age 2 years, he had viral encephalitis 12 days after receiving the yellow fever vaccine and at age 4 he had shingles 1 week after the varicella vaccine. At age 5 he had 45 days of rotavirus positive diarrhea (patient had been vaccinated). Six months later he was diagnosed with calcaneus osteomyelitis. Tendon biopsy showed caseous necrosis and PCR was positive for Mycobacterium sp and negative for M. tuberculosis. At age 6 years, he was admitted due to hepatic abscesses and again, a month later, for headache and dizziness. Two weeks later he presented with acute hearing loss which evolved to total hearing loss on the left side and partial loss on the right side. Two months later he had two episodes of chorea and 3 months later, one episode of autoimmune hemolytic anemia. Laboratory test findings included persistent leukopenia (533cells/mm3) and normal immunoglobulins levels. Immunophenotyping showed low T and B lymphocyte counts (CD3+255/CD20+ 42-7%), decreased number of naïve CD4+ and CD8+ lymphocytes (4-0,57% and 13-2,26%, respectively) and increased percentage of NK cells (51,1%). Three pathogenic mutations were found in the RAG1 gene, confirming the diagnosis of TlowBlowNK+ SCID. Patient underwent hematopoietic stem cell transplantation with a HLA-matched sibling donor 2 months ago and is doing well so far.
Conclusions: The milder phenotype of SCID hypomorphic mutations also represents significant morbidity.