SEVERE COMBINED IMMUNODEFICIENCY - A RETROSPECTIVE SINGLE-CENTER STUDY OF CLINICAL PRESENTATION AND OUTCOME IN 117 PATIENTS

We carried out a retrospective analysis of 147 patients with severe co mbined immunodeficiency who were examined in a single center between J an. 1, 1970, and Jan. 1, 1992, for the purpose of evaluating disease o nset, progression, and outcome. The frequency of case referral increas ed from 8 from 1970 to 1975 to 56 from 1986 to 1991. The most frequent phenotype was T-/B+ (absence of T lymphocytes and presence of B lymph ocytes) (n = 51); there were 36 cases of alymphocytosis, 16 of adenosi ne deaminase deficiency, 13 of Omenn syndrome, and 1 of reticular dysg enesis. Protracted diarrhea and lung infections were the main infectio us complications; infection with bacillus Calmette-Guerin occurred in 10 of 28 vaccinated patients, but none of the six recipients of oral p olio vaccine subsequently had poliomyelitis. The presence of maternal T cells was suspected or proved in half the patients with alymphocytos is or T-B+ severe combined immunodeficiency but did not occur in the o ther forms of the disease. Of the 117 patients, 22 died before transpl antation could be performed. Adenosine deaminase deficiency and Omenn syndrome were more frequently associated with death before hematopoiet ic stem cell transplantation was possible. Fetal liver transplantation was successful in 1 of 10 cases. The survival rate among the 30 recip ients of bone marrow with identical human leukocyte antigens (HLA) was 80%, with a median follow-up of 129 months; 23 of 25 patients recover ed full immune function. The survival rate among the 50 recipients of HLA-haploidentical T cell-depleted bone marrow was 56%, with a mean fo llow-up of 35 months. Of the latter patients, 10 (35%) still require i mmunoglobulin substitution. There has been a trend toward improvement in the survival rate of haploidentical bone marrow recipients, presuma bly because of more effective infection-control measures and better tr ansplantation strategy.