Occurrence of Aggregatibacter actinomycetemcomitans in Brazilian indians from Umutina Reservation, Mato Grosso, Brazil

Abstract

A ggregatibacter actinomycetemcomitans is associated with periodontal disease, especially localized aggressive periodontitis, produces a potent leukotoxin and its distribution is influenced by ethnic characteristics of the population.Objective:Using culture and polymerase chain reaction (PCR) techniques, this study evaluated the occurrence of this microorganism and the distribution of leukotoxic strains isolated from Indians belonging to the Umutima Reservation, Mato Grosso, Brazil.Material and Methods:Forty-eight native Brazilians with gingivitis and 38 with chronic periodontitis, belonging to Umutina, Paresi, Bororo, Bakairi, Kayabi, Irantxe, Nambikwara and Terena ethnicities, were studied. Subgingival, supragingival and saliva samples of each patient were collected and transferred to VMGA III medium and to ultra pure Milli Q water. Bacteria were grown on TSBV agar and incubated in anaerobiosis (90% N2 + 10% CO2) at 37°C for 72 h. The presence of the ltx promoter was determined by PCR, and a 530 bp deletion in the promoter was evaluated by using specific primers.Results: A. actinomycetemcomitans was isolated from 8.33% of saliva, supragingival and subgingival samples from patients with gingivitis and from 18.42% of saliva and supragingival biofilm, and 26.32% subgingival biofilm from patients with chronic periodontitis. By PCR, the bacterial DNA was detected in 8.33% of saliva, supragingival and subgingival biofilms from patients with gingivitis and from 23.68% of saliva, 28.95% supragingival biofilm and 34.21% subgingival biofilm from patients with periodontitis. All strains were grouped as non-JP2 clones based on the absence of deletion in the leukotoxin promoter. Differences among the microbial and clinical parameters in patients were analyzed by using the Mann-Whitney, Chi-square or Fisher's exact tests.Conclusions:The present results suggest that A. actinomycetemcomitans can be related to the attachment loss in this population, but the presence of minimally leukotoxic strains, as well as its role in the pathogenesis of the periodontitis in these native Brazilians need to be further investigated.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24‐mo prospective multicenter cohort study

“…Meanwhile, A. actinomycetemcomitans and Tannerella forsythia were not reliably detected by sampling either saliva or periodontal pockets. Other studies also found that a salivary sample alone did not identify all individuals infected with A. actinomycetemcomitans . From these results, Slots & Slots have reviewed that saliva seems to be superior to periodontal pocket samples for detecting P. gingivalis , P. intermedia , P. nigrescens and T. denticola , but reasonably good accuracy may be necessary for detection of A. actinomycetemcomitans and T .…”

Occurrence of Aggregatibacter actinomycetemcomitans in Brazilians with chronic periodontitis

“…Additionally, such variations in the global distribution of periodontopathic bacteria could be important in the epidemiology and the treatment of periodontal diseases. In view of the limited data available on the Brazilian distribution of A. actinomycetemcomitans in chronic periodontitis subjects 5,7,22,23 and as this bacterium was also considered a true pathogen, we examined the occurrence of A. actinomycetemcomitans in Brazilian subjects with mild, moderate and severe chronic periodontitis.…”

“…Recently, an interesting study was conducted by Vieira et al 23 (2009) in native Brazilians. The authors included 38 patients with periodontitis.…”

The Microbial Aetiology of Periodontal Diseases

“…Cortelli et al, (2005) recommended that serotype b be used as a diagnostic marker for aggressive periodontitis since they found a high prevalence of the JP2 clone in a Brazilian population. These findings have been contradicted by other studies on Brazilians which showed very low, if any, serotype b strains (Vieira et al, 2009;Roman-Torres et al, 2010). Yet another study showed similar frequencies of serotypes b and c but associated serotype b with health and c with disease (Teixeira et al, (2006).…”

“…Yet another study showed similar frequencies of serotypes b and c but associated serotype b with health and c with disease (Teixeira et al, (2006). The contradictions in these results may be due to the fact that Brazil has a multi-ethnic population of predominantly African and Mediterranean origin, while the native Brazilians, descending from almost extinct ethnic groups who live in cultural isolation with no mixing with other ethnic groups (Vieira et al, 2009), have not been exposed to the toxic strains of Aa.…”