[the early diagnosis of the vertical transmission of the human immunodeficiency virus type 1. The evaluation of diagnostic tests]

BACKGROUND

The early diagnosis of vertically transmitted human immunodeficiency virus infection cannot be based on the presence of specific serum antibodies since those of the maternal IgG class pass the placenta and may be detected in children for up to 18 months. Based on this fact, the aim of this study was to evaluate other techniques for early diagnosis of the infection applicable from birth in 306 children of infected mothers.

METHODS

The production of in vitro antibodies, virus culture and polymerase chain reaction (PCR) were used. The sensitivity of the techniques was estimated in the 40 children diagnosed with human immunodeficiency virus infection and specificity was determined in the 266 uninfected children.

RESULTS

The sensitivity for the production of in vitro antibodies was 62.0% at 3 months and 94.7% at 6 months; 90.4% and 88.2%, respectively, for the viral culture and 92.3% and 94.1%, respectively, for the PCR. The specificity of all the cases was higher than 89.4% although varied in relation to age.

CONCLUSIONS

The combination of several diagnostic techniques provides better performance for the early diagnosis of vertical transmission of the human immunodeficiency virus. Given that viral culture takes longer to provide results and is more expensive, it is less recommendable for routine use, although the form of viral replication may be useful to establish the prognosis.

[Azidothymidine in the treatment of patients with human immunodeficiency virus infection and persistent generalized adenopathies]

The effectiveness and security of azidothymidine (AZT) in the treatment of patients with infection by the human immunodeficiency virus (HIV) and persistent generalized adenopathies (PGA), were assessed. Thirty six patients with HIV infection and PGA participate in the study. Eighteen were treated with AZT and the other 18 were included in the control group, since they did not accept the treatment. Both groups were homogeneous with respect to their clinical, immunological and virological characteristics. A common study protocol was used and the clinical, immunological and virological effectiveness was assessed. Lymphocyte subpopulations were quantified by flow cytometry, viral antigens were determined by sandwich-type ELISA and antibodies against viral proteins (anti-gp120, anti-gp160, anti-gp41, anti-gp24 and anti-p18) were detected by Western blot. Naranjo and Busto's algorithm was used for the causality of adverse effects. We did not observe any significant differences regarding the presence of infection and the evolution of AIDS in both groups. A positive response to thrombocytopenia was observed, more evident in patients under low doses of AZT. The small initial transitory improvement of the immunological parameters was not statistically significant. The viral antigen was not modified by the treatment. With respect to the behaviour of the several antibodies studied, no differences were observed. The initial doses of AZT had to be modified in 44% of patients due to their hematological toxicity, more frequent in the first stages of the treatment. In two patients, the treatment had to be finally discontinued due to severe neutropenia. 25% of patients showed mild to moderate gastrointestinal manifestations.(ABSTRACT TRUNCATED AT 250 WORDS)

[Evaluation of IgG-IgM antibodies against the Epstein-Barr virus nuclear antigen (EBNA-1) using ELISA]

BACKGROUND

Evaluation of two commercial immunoenzymatic techniques (ELISA) for detection of anti-EBNA-1 IgG and IgM for diagnosis of Epstein-Barr virus mononucleosis.

METHODS

Study of anti-EBNA-1 IgG and IgM in infectious mononucleosis and they have been compared with the detection of IgM antibodies to VCA by indirect immunofluorescence as the reference method.

RESULTS

The sensitivity of the assay was 87.5%, the specificity was 89.4%, the positive predictive value was 91.4% and the negative predictive value was 85%.

CONCLUSIONS

This technique can be useful in laboratories without the necessary equipment and experienced personnel for indirect immunofluorescence. It also can be used as a complementary determination to the anti-VCA IgM in the long lasting infectious mononucleosis, when this marker is negative.

[Long-term follow-up study of 35 children with ADS treated with zidovudine (AZT)]

Thirty-five children diagnosed of AIDS were studied in order to evaluate toxicity and efficacy of oral Zidovudine treatment (AZT), as well as to analyze the clinical, biochemical, immunological and virological evolution of HIV infection throughout the treatment. Patients (19 males and 16 females) were studied from April 1988 to May 1990 with a mean follow-up time of 13.5 months (SD = 6.7 months). The mean age of the group was 4.68 years. The means of acquisition of this disease was 71.45 vertical and 28.6% via hemo-derivatives. Tolerance has been good with the main toxicity being hematological (28.5% anemia and/or neutropenia), 23% of which required blood supplements. The presence of neurological involvement and thrombopenia were observed in the incidence of greater toxicity. No influence on weight during AXT treatment was observed and hepatosplenomegalia and adenopathies were not modified. Bacterial and opportunistic infections were observed in 97.1% and 20% of patients, respectively. Neurological evolution was irregular and the improvement observed in some patients was mild and transitory. Three patients died during the follow-up from intercurrent infectious process. A progressive increase in MCV and a tendency towards leucopenia and lymphopenia (mainly in hemo-derivative infected patients) was observed. Neither significant immunological nor virological changes were observed during the treatment (except the tendency to diminish basal hypergammaglobulinemia). The results of this study were compared to other pediatric series treated with AZT.

[Mononucleosis caused by cytomegalovirus]

Sixteen cases of mononucleosis due to cytomegalovirus, are presented. The selection of patients was based on clinical criteria. Symptoms are compared with another series of patients affected with mononucleosis by Epstein-Barr virus. We have not found differences comparing the fever, cervical adenopathies and faringoamigdalitis. Differences were significant in hepatomegaly. We conclude that the clinical picture of cytomegalovirus mononucleosis is very similar to those of the Epstein-Barr mononucleosis.