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Live viral vaccines in patients with DiGeorge syndrome
Clinical Immunology 113 (2004) 3 www.elsevier.com/locate/yclim
Editorial
Live viral vaccines in patients with DiGeorge syndrome The issue of how best to protect immunodeficient patients exposed to a multitude of infectious threats daily is one that continues to inspire vigorous debate among clinicians. One extreme is to completely eliminate infectious exposures through strict isolation. Many clinicians attempt to walk the fine line between protection from excessive risk and the opportunity to lead a normal life. With the exception of studies of patients with HIV, there is little evidence to support one particular strategy over another. In this regard, the article by Moylett et al. [1] the July 2004 issue of Clinical Immunology offers a significant contribution for immunologists. Dr. Moylett and her colleagues have studied the risks and benefits of live viral vaccine administration for patients with DiGeorge syndrome who have a modest compromise in T-cell numbers. Chromosome 22q11.2 deletion syndrome, which is often the cause of DiGeorge syndrome, is found in 1:3000 children [2]. Thus, this study is of enormous interest from a public health perspective. Package inserts for live viral vaccines contain the explicit warning that patients with known immunodeficiencies should not receive these vaccines. These package inserts have placed a medico-legal burden on clinicians. This study and a previous one exploited a group of patients who were diagnosed with DiGeorge syndrome after live viral vaccine administration [1,3]. A retrospective review of patients by chart review or questionnaire revealed infrequent adverse events from live viral vaccine administration and a high rate of communityacquired varicella in those patients not immunized. These data support the use of live viral vaccines to protect patients with DiGeorge syndrome. An extremely important caveat to this study is that the patients in the study had minimal to moderate compromise in T-cell production. The fact that many of them were diagnosed after the vaccine administration argues strongly that they were not having significant immunologic compromise. This article therefore, provides significant new information on the safety of live viral vaccines for many patients with DiGeorge syndrome but does not address the more thorny issue of who should not receive the vaccine. For example, no immunologist is going to administer live viral vaccines to a patient with DiGeorge syndrome who has a Tcell count of <100 cells/mm3. Of course, such a patient would be unlikely to survive without a thymus transplant
1521-6616/$ - see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.clim.2004.04.004
[4]. Nevertheless, a few patients described in the literature have survived with remarkably low T-cell counts, although with significant infections [5]. Would an immunologist be comfortable administering live viral vaccines to a patient with a T-cell count of 300 cells/mm3? Some would feel comfortable with immunizing a patient whose T cells are in the range of 500 cells/mm3, but many would not. Although there is wealth of data on the safety of live viral vaccine administration in HIV, it is dangerous to extrapolate from these data because the mechanisms of immunologic compromise are so different. Therefore, this article provides important information for clinicians, and we can hope that further information on the patients with significant compromise in T-cell production will be forthcoming soon.
References [1] E.H. Moylett, A.N. Wasan, L.M. Noroski, et al., Live viral vaccines in patients with partial DiGeorge syndrome: clinical experience and cellular immunity, Clin. Immunol. 112 (2004) 106 – 112. [2] K. Devriendt, J.P. Fryns, G. Mortier, et al., The annual incidence of DiGeorge/velocardiofacial syndrome, J. Med. Genet. 35 (1998) 789 – 790. [3] E.E. Perez, A. Bokszczanin, D. McDonald-McGinn, et al., Safety of live viral vaccines in patients with chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome), Pediatrics 112 (2003) e325. [4] M.L. Markert, A. Boeck, L.P. Hale, et al., Transplantation of thymus tissue in complete DiGeorge syndrome, N. Engl. J. Med. 341 (1999) 1180 – 1189. [5] J. Bastian, S. Law, L. Vogler, et al., Prediction of persistent immunodeficiency in the DiGeorge anomaly, J. Pediatr. 115 (1989) 391 – 396.
Kathleen E. Sullivan * Children’s Hospital of Philadelphia, Division of Immunologic and Infectious Disease, Philadelphia, PA 19104-4399, USA E-mail address: [email protected] 12 April 2004
* Children’s Hospital of Philadelphia, Division of Immunologic and Infectious Disease, 34th and Civic Center Boulevard, Philadelphia, PA 19104-4399. Fax: +1-215-590-3044.
Editorial
Live viral vaccines in patients with DiGeorge syndrome The issue of how best to protect immunodeficient patients exposed to a multitude of infectious threats daily is one that continues to inspire vigorous debate among clinicians. One extreme is to completely eliminate infectious exposures through strict isolation. Many clinicians attempt to walk the fine line between protection from excessive risk and the opportunity to lead a normal life. With the exception of studies of patients with HIV, there is little evidence to support one particular strategy over another. In this regard, the article by Moylett et al. [1] the July 2004 issue of Clinical Immunology offers a significant contribution for immunologists. Dr. Moylett and her colleagues have studied the risks and benefits of live viral vaccine administration for patients with DiGeorge syndrome who have a modest compromise in T-cell numbers. Chromosome 22q11.2 deletion syndrome, which is often the cause of DiGeorge syndrome, is found in 1:3000 children [2]. Thus, this study is of enormous interest from a public health perspective. Package inserts for live viral vaccines contain the explicit warning that patients with known immunodeficiencies should not receive these vaccines. These package inserts have placed a medico-legal burden on clinicians. This study and a previous one exploited a group of patients who were diagnosed with DiGeorge syndrome after live viral vaccine administration [1,3]. A retrospective review of patients by chart review or questionnaire revealed infrequent adverse events from live viral vaccine administration and a high rate of communityacquired varicella in those patients not immunized. These data support the use of live viral vaccines to protect patients with DiGeorge syndrome. An extremely important caveat to this study is that the patients in the study had minimal to moderate compromise in T-cell production. The fact that many of them were diagnosed after the vaccine administration argues strongly that they were not having significant immunologic compromise. This article therefore, provides significant new information on the safety of live viral vaccines for many patients with DiGeorge syndrome but does not address the more thorny issue of who should not receive the vaccine. For example, no immunologist is going to administer live viral vaccines to a patient with DiGeorge syndrome who has a Tcell count of <100 cells/mm3. Of course, such a patient would be unlikely to survive without a thymus transplant
1521-6616/$ - see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.clim.2004.04.004
[4]. Nevertheless, a few patients described in the literature have survived with remarkably low T-cell counts, although with significant infections [5]. Would an immunologist be comfortable administering live viral vaccines to a patient with a T-cell count of 300 cells/mm3? Some would feel comfortable with immunizing a patient whose T cells are in the range of 500 cells/mm3, but many would not. Although there is wealth of data on the safety of live viral vaccine administration in HIV, it is dangerous to extrapolate from these data because the mechanisms of immunologic compromise are so different. Therefore, this article provides important information for clinicians, and we can hope that further information on the patients with significant compromise in T-cell production will be forthcoming soon.
References [1] E.H. Moylett, A.N. Wasan, L.M. Noroski, et al., Live viral vaccines in patients with partial DiGeorge syndrome: clinical experience and cellular immunity, Clin. Immunol. 112 (2004) 106 – 112. [2] K. Devriendt, J.P. Fryns, G. Mortier, et al., The annual incidence of DiGeorge/velocardiofacial syndrome, J. Med. Genet. 35 (1998) 789 – 790. [3] E.E. Perez, A. Bokszczanin, D. McDonald-McGinn, et al., Safety of live viral vaccines in patients with chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome), Pediatrics 112 (2003) e325. [4] M.L. Markert, A. Boeck, L.P. Hale, et al., Transplantation of thymus tissue in complete DiGeorge syndrome, N. Engl. J. Med. 341 (1999) 1180 – 1189. [5] J. Bastian, S. Law, L. Vogler, et al., Prediction of persistent immunodeficiency in the DiGeorge anomaly, J. Pediatr. 115 (1989) 391 – 396.
Kathleen E. Sullivan * Children’s Hospital of Philadelphia, Division of Immunologic and Infectious Disease, Philadelphia, PA 19104-4399, USA E-mail address: [email protected] 12 April 2004
* Children’s Hospital of Philadelphia, Division of Immunologic and Infectious Disease, 34th and Civic Center Boulevard, Philadelphia, PA 19104-4399. Fax: +1-215-590-3044.