[Characterization and distribution of Citrobacter species in a university hospital]

OBJECTIVE

[corrected] a) To identify Citrobacter strains following the conventional biochemical reaction of Brenner and col; b) to evaluate the sensitivity and specificity of the O'Hara's method compared with Brenner's method, and c) to determine the rate and distribution of the strains in the clinical isolates.

MATERIAL AND METHODS

One hundred and twenty two clinical isolates, characterized as Citrobacter spp. were collected between May of 1994 and August of 1997. Clinical isolates included inpatients and outpatients from Hospital de Clínicas. Strains were identified following the methods of Brenner and O'Hara.

RESULTS

Methods of Brenner identified 111 of 122 strains: C. freundii 59 of 111; C. koseri 18 of 111; C. werkmanii 15 of 111; C. braakii 9 of 111; C. youngae 6 of 111 and C. amalonaticus 4 of 111. O'Hara's methods identified 104 of 111 strains (94%). C. freundii was recovered most frequently from urine and feces (p Fisher < 0.026 and 0.039 respectively), while C. koseri was isolated from urine principally (p Fisher < 0.0372).

CONCLUSIONS

The genus Citrobacter is an important opportunistic pathogen that can be identified in clinical microbiology laboratories using O'Hara's method.

[Measurement of total serum IgE by enzyme immunoassay with three commercial reagents]

We measured total serum IgE in 14 patients with allergic diseases and 16 healthy subjects, using three commercial ELISA kits. The correlation of results among the three kits was analyzed using Passing and Bablock regression parameters. Results show that measurements of the different kits do not coincide. One kit shows differences using sera from normal subjects. There is no correlation among kits when using sera from allergic patients. It is concluded that it is not possible to determine exactly the amount of IgE using these kits, specially in subjects with elevated levels.

Multivariate statistical brain electromagnetic mapping

Brain Electromagnetic Topography (BET) has attained widespread use. The representation of EEG or MEG parameters as scalp maps (BETm) aids its clinical interpretation. However, some critical issues limit the usefulness of BETm. In particular, the conventional statistical assessment of BETm with respect to normative data is based upon marginal significance probability scales which involve multiple univariate comparisons (one at each recording site). As a consequence, the probability of false positive findings (type I error) is increased above its nominal level. The use of conservative levels avoids this phenomenon but results in a considerable increase of the probability of not detecting real abnormality (type II error). Furthermore, BETm are constructed without taking into consideration the patterns of correlations characteristic of electromagnetic data under normal states of brain functioning. This limits the capability of BETm of representing multivariate aspects of abnormality. This paper introduces some techniques to approach these difficulties. Multivariate Brain Electromagnetic Topographic maps (MBETm) are defined, which retain the attractive features of mapping but also take advantage of multivariate characteristics (in the spatial and frequency domains) to highlight aspects of neuropathology. Moreover, simultaneous significance probability (SSP) scales, valid for both BETm and MBETm, are introduced for the global control of the probability of a type I error. The use of these techniques is illustrated with data from patients with cortical tumours and with epilepsy. ROC analysis shows that in some cases there is a significant improvement in both detection and localization accuracy.

[B-DR (HLA) linkage imbalance and transplants in Chile: a preliminary report]

Linkage imbalance for the B and DR loci (HLA) was found in a Chilean sample of families where a member had been proposed for transplantation. The B7-DR2 and B14-DR1 haplotypes were significantly more frequent than expected. Most associations were those found in Caucasian populations.

Cyclosporine A in five children with severe aplastic anemia

Five children with aplastic anemia (AA) were treated with Cyclosporine A (CyA) after failure or poor response to other immunosuppressive agents. A complete remission was achieved in 3 patients, a good partial response in 1, and a poor partial response in another. In 1 patient in whom a complete remission was obtained, a relapse occurred 4 months after CyA was stopped. The treatment was resumed and a complete remission was again observed. Four patients were still on treatment, and side effects were mild. CyA appeared to be an effective treatment in AA.

[Hemagglutination inhibition reaction for rubella virus. A simplified technic]

A comparação dos resultados obtidos com uma técnica simplificada de inibição da hemaglutinação para o vírus da rubéola e a técnica padronizada pelo "Center for Disease Control", permitiu determinar índices de sensibilidade e especificidade da técnica simplificada em relação à técnica padrão de, respectivamente, 99,4% e 90,0%. Esta técnica pode facilitar a execução de levantamentos sorológicos para a rubéola em larga escala.