Evaluación de la coloración de Albert para la identificación de Corynebacterium spp. en flujo vaginal / Evaluation of Albert´s staining technique for Corynebacterium spp. in vaginal swabs

Introducción: la detección del género Corynebacterium en flujo vaginal representa un reto para el estudio de su posible papel patogénico en el tracto genital femenino. La coloración de Gram es la técnica recomendada para la detección de corinebacterias en muestras clínicas; no obstante, algunas características biológicas de estas bacterias dificultan la identificación por medio de esta. Objetivo: evaluar el desempeño de la coloración de Albert para la identificación de Corynebacterium spp. en muestras de flujo vaginal. Materiales y métodos: se evaluó la tinción de Albert como prueba diagnóstica para la identificación de Corynebacterium spp. en 451 flujos vaginales en comparación de la coloración de Gram. Se calculó la sensibilidad, la especificidad, los valores predictivos, las razones de verosimilitud y el índice J de Youden con el software Epidat 3.1. Resultados: la coloración de Albert presentó sensibilidad y especificidad de 61,5% y 74,6%, respectivamente, valor predictivo positivo de 78,3%, valor predictivo negativo de 56,5%, razón de verosimilitud positiva de 2,4 y negativa de 0,5 y un Índice de Youden de 0,4. Conclusiones: la tinción de Albert no mostró un mejor rendimiento que la coloración de Gram en la identificación del género Corynebacterium en muestras de flujo vaginal. Por lo tanto, se recomienda el uso en conjunto de las coloraciones de Gram y Albert para la identificación de corinebacterias en flujo vaginal. (AU)

Introduction: The detection of Corynebacterium genus in vaginal discharge represents a challenge for the study of its possible pathogenic role in the female genital tract. Gram's stain is recommended for corynebacteria detection in clinical samples, however, some biological characteristics of these bacteria difficult their identification by this technique. Objetive: to evaluate Albert's stain performans to identify Corynebacterium spp. in vaginal discharge. Materials and methods: Albert's stain was evaluated as a diagnostic test for the identification of Corynebacterium spp. in 451 vaginal swabs in comparison to Gram's stain. Sensitivity, specificity, predictive values, likelihood ratio, as well as Youden's J index were calculated using Epidat software 3.1 version. Results: Albert's stain had a sensitivity and specificity of 61.5% and 74.6%, respectively, positive predictive value of 78.3 %, negative predictive value of 56.5 %, positive likelihood ratio of 2.4 and negative likelihood ratio of 0.5, as well as Youden index of 0.4. Conclusions: Albert's stain did not show better performance than Gram's stain for identification of corynebacteria in vaginal swabs. Thereforeit is recommended the concomitant use of the Gram and Albert stains for the identification of corynebacteria in vaginal discharge. (AU)

Isolation, speciation, and antibiogram of clinically relevant non-diphtherial Corynebacteria (Diphtheroids).

Purpose: Coryneform or the non-diphtherial Corynebacterium species largely remains a neglected group with the traditional consideration of these organisms as contaminants. This concept, however, is slowly changing in the light of recent observations. This study has been done to find out the species distribution and antibiogram of various members of the clinically relevant Coryneform group, isolated from various clinical materials. Materials and Methods: One hundred and fourteen non-duplicate isolates of diphtheroids from various clinical isolates were selected for the study. The isolates were identified to the species level by using a battery of tests; and antimicrobial susceptibility was tested by using a combination of Clinical and Laboratory Standards Institute (CLSI) and the British Society for Antimicrobial Chemotherapy (BSAC) guidelines, in the absence of definitive CLSI guidelines. Results: Corynebacterium amycolatum was the predominant species (35.9%) in our series followed by the CDC Group G organisms (15.7%). Each of the remaining 19 species comprised of less than 10% of the isolates. More than half the total isolates were resistant to the penicillins, erythromycin, and clindamycin; while excellent activity (all the strains being susceptible) was shown by vancomycin, linezolid, and tigecycline. Chloramphenicol and tetracycline also had good activity in inhibiting more than 80% of the isolates. Multiply drug resistance was exhibited by all the species. Conclusion: This study was an attempt to establish the clinical significance of coryneform organisms. The high level of resistance shown by this group to some of the common antibacterial agents highlights the importance of processing these isolates in select conditions to guide the clinicians towards an appropriate therapy.

Normal Flora of the Skin in Korean Peoples / 대한피부과학회지

Skin floras were taken from forehead, sternal area, lower margin of axillae, and interscapular space of 50 healthy Koreans(M 30, F 20) between 18 year and 40 years old using Williamson and Kligman's method and modified Pilsburg and .Nichols method. After incubating these floras for 3-5 days aerobically and anaerobically, we identified them using various stains and biochemical tests. The most common flora was Corynebucterium acne(84%), followed by aerobic diphtheroids(14%), coagulase negative staphylococcus, Micrococcus in orders. Although transient floras including Staphylococcus aareas, Pseudomonas, Listeria monocytogenes, and other Gram negative bacilli were isolated, they were rare and did mainly from axilla. The most common resident site of Corynebacteirium acne was forehead (l. 67 x 10/cm), but in aerobic diphtheroids and Micrococcaceae was the lower margin of axilla(2.70x16/cm, 2.34x10/cm), in which aerobic floras were more than anaerobics. The incidence rate of lipophilic diphtheroid was 27%, however it was 35% in axilla. The aerobic diphtheroid capable of nitrate reduction was 26%, which was very common in forehead. Among Propionibacterium species, Propionibacterim(P) acne was isolated 100% from all sites, but P. grandulosum was only in 2-7% and P. avidum was not.