Response to polysaccharide antigens in patients with ataxia-telangiectasia

OBJECTIVE: To analyze the production of antibodies to polysaccharide antigens in patients with ataxia-telangiectasia.PATIENTS AND METHODS: We used the ELISA technique to measure the levels of IgG antibodies to serotypes 1, 3, 5, 6B, 9V and 14 of Streptococcus pneumoniae in 14 patients with ataxia-telangiectasia before and after immunization with 23-valent polysaccharide vaccine. Adequate response to individual polysaccharide can be defined as a postimmunization antibody titer equal to or greater than 1.3 µg/ml or as a minimum fourfold increase over the baseline (preimmunization) value. RESULTS: Six (43%) patients showed an absent response to all serotypes analyzed. Four patients showed adequate response to only one serotype, one patient to two serotypes, two patients to three serotypes and only one patient to four out of six serotypes analyzed. No patient had adequate response to all serotypes tested. Postimmunization pneumococcus IgG levels were higher than preimmunization levels to all serotypes analyzed, except for serotype 3. In spite of this, the mean postimmunization levels were lower than 1.3 µg/ml in all serotypes, except for serotype 14. Mean increment was less than four in all serotypes analyzed. CONCLUSION: Our results suggest that patients with ataxia-telangiectasia are at a high risk of having an impaired response to pneumococcus, which may be one of the causes of recurrent sinopulmonary infections in these patients.

Analysis of immunoglobulin deficiency cases: a five year study.

A total of 734 serum specimens from various clinical disorders along with 100 control samples from healthy subjects were processed for estimation of serum IgG, IgA and IgM employing single radial immunodiffusion procedure. Immunoglobulin deficiency, either selective or combined was noted in 31 males and 24 females in all age groups. Of the 55 cases encountered it was secondary immunoglobulin deficiency which was seen on a larger scale and encountered in patients with Multiple myeloma (16 out of 32) followed by Leprosy (14 out of 250), Lymphoma (5 out of 43), Malaria (4 out of 137), Burns (4 out of 52), Rheumatoid arthritis (2 out of 69) and non lymphoreticular malignancies (1 out of 41) in decreasing order of frequency. Primary immunoglobulin deficiency was observed in nine cases comprising of six belonging to Idiopathic late onset immunoglobulin deficiency, two of dysgammaglobulineamia and a solitary case of Ataxia telangiectasia. Panimmunoglobulin deficiency was observed in six cases, 11 had a dual deficiency while 38 showed deficiency of an isolated class with selective IgA deficiency in 20 cases. Furthermore, one patient each had total absence of IgG or IgA while IgM was not detectable in seven patients. A high suspicion index along with a regular rapport between the clinician and the laboratory personnel is necessary in the diagnostic set up of immunoglobulin deficiency states.

Detección de heterocigotos de ataxia telangiectasia por la sensibilidad a la radiación ionizante / Detection of heterocygotic with patients with ataxia telangiectasia show chromosomic rupture

Investigaciones recientes han demostrado que los pacientes homocigotos y heterocigotos de ataxia telangiectasia (AT) tienen rompimientos cromosómicos. De acuerdo con esta característica se diseñó el estudio inducido rompimientos cromosómicos en células granulocíticas de pacientes con diagnóstico de AT, heterocigotos obligados de AT y comparados con un grupo de individuos sanos. A todos los pacientes se les cuantificó el número de rompimientos cromosómicos con 14 dosis de radiación 125 kv, 125 mA. Los resultados sugieren diferencias significativas en el número de alteraciones estructurales cromosómicas inducidas por la radiación en los granulocitos de heterocigotos de ataxia telangiectasia similares a las alteraciones estructurales de los linfocitos de pacientes con AT y se demuestra que estas alteraciones se presentan preferentemente en un cromosoma del grupo C de homocigotos y heterocigotos de AT

Immune status in ataxia telangiectasia.

Immune status of 22 patients of ataxia telangiectasia was studied over a period of 8 yr (mean age of patients: 9.5 +/- 3 yr; 9 of 22 were siblings). Low T-cell number was observed in 14 of 19 patients but the response to PHA challenge done in 10 patients was normal and migration inhibition to BCG antigen was positive in 6 of 6 patients. IgM defect was seen in 2 out of 18 patients and serum IgA was deficient in 10 out of 18 patients. Salivary IgA was also absent in these children. Four children had high spontaneous NBT reduction. None of the patients had lymphoma, leukemia or any other malignancy at the time of presentation. Candida killing was normal in all patients. The presenting feature related to the CNS in almost all children and gross infections were not seen.

Primary immunodeficiency diseases: a presentation of 6 cases

The peripheral blood leukocytes of 6 children with clinical data suggestive of primary cellular immunodeficiencies were studied in an attempt the cellular basis of these disorders. The phenotype and function of T and B cells were investigated. According to the clinical and laboratory fetures, the patients were classified as one case of severe combined immunodeficiency (SCID), two of ataxia-telangiectasia (AT), one of Wiskott-Aldrich syndrome (WAAS), one of /edi%george syndrome (DSG), and one of cellular immunodeficiency (CID). The laboratory investigations together with the clinical manifestations permitted a diagnosis of primary immunodeficiency diseases

Primary immune disorders in children and their diagnosis.

The clinical features and laboratory findings of 18 children with various primary immune deficiencies and their immunologic diagnosis have been discussed. In 3 patients of ataxia telangiectasis human foetal thymus transplantations have been performed with some success.