This allowed us to relate these data to specific clinical pictures -- patients who had earlier been diagnosed with epilepsy, myoclonic epilepsy, evoving epilepsy, epileptigenic encephalopathy, autism, West Syndrome, and Angelman's Syndrome. All the patients had presented with the first symptoms shortly after receiving the prophylactic vaccination or somewhat later.

The first symptoms were convulsions, very high fever, or diarrhoea immediately following a compulsory vaccination. The parents had told their physicians about this; then, after taking EEGs and visiting neuropsychiatric specialists or pediatricians without getting any satisfaction, the physicians had administered the recall shots of the vaccines leading very shortly to stabilization of the condition with progressive clinical deterioration.

These children were mostly from 3 to 9 months old. All patients were studied for the presence of metabolic diseases with negative results; then chromosomal mapping was done, also with negative results; encephalic TAC and RMN were performed at first appearance of the symptomatology, also with negative results.

The EEG performed at first appearance of the symptomatology gave a negative result in 92% of the patients. Serologic investigations for herpetic virus (IgG and IgM) were positive in all for IgG and negative for all for IgM, leading us to estimate seropositivity (IgG) for Epstein-Barr virus of 73.8%, for cytomegalovirus of 71.4%, for Herpes Simplex virus of 47.6%, and for Varicella-Zoster Virus of 21.4%. In all the patients we observed diminished sideremia and a deficit of IgA and IgG with a slight increase of GOT and GPT. None of the patients had maternally transmitted viral encephalopathy, and in all the patients the vegetative and relational life was quite normal prior to administration of the first dose of vaccine.

The patients were subjected to HLA tissue typing (A, B, and C), and serologic HLA DR-DQ, with the aim of checking a possible correlation with the emergence of CNS pathology, and these antigens indicate a possible autoimmune immunogenetic basis for the demyelination process. (See A. Svejgard, P. Platz, and L. P. Ryder in Immunology Rev. 70, 1983, 193). The chi-square statistical analysis, with the Italian population as a control (see 11th International Histocompatibility Workship and Conference, 1992) demonstrated an increase in the HLA-A3 antigen (43.3% vs. 25%, P = 0.04, after statistical correction) and the HLA-DR7 antigen (48.3% vs. 24.14% P = 0.007 after statistical correction). The presence of A3 and/or DR7 was observed in 22/30 (73.3%) of the patients.

Additional cases are under study to better define the possible association of HLA A3 and/or HLA DR7 with appearance of this pathology in the CNS following vaccination. HLA system alleles have an elevated genetic polymorphism and are inherited as autosomal dominant characteristics. The combination of the alleles of various loci in the same chromosomes has been defined as the haplotype or complex gene, and the complexity of the HLA region demonstrates, besides the thousand different possible haplotypes, also the problems: of molecular resemblance (see G. Laurentaci and B. Favoino, "Immunogenetica e malattie HLA Associate," Dedalo Litostampo, Bari, 1991), of discriminating between self- and non-self-antigens, and of determining the function of the Class 2a CMI molecules; any interference with the process of presentation of the antigen can predispose to an autoimmune disease. Alterations which do not occur can be due to the action of viral agents which compromise the specific immune response because of their resemblance to the "self" tissue antigens. The consequence is persistence of the infective agents and a tendency to provoke, through a marked reaction, induction of an autoimmune disease. This can present in conditions of marked reactivity to some viruses and to myelin antigens.