Assessment of peripheral neutrophil functions in patients with localized aggressive periodontitis in the Indian population.

BACKGROUND: Localized aggressive periodontitis (LAP) patients exhibit abnormal neutrophil functions to a variety of environmental and host stimuli. The aim of the present study was to evaluate neutrophils chemotaxis, phagocytosis, microbicidal activity and superoxide generation in LAP patients of Indian origin. MATERIALS AND METHODS: Eleven LAP patients and nine healthy subjects were included in the study. Neutrophil chemotaxis was evaluated against an alkali-soluble casein solution using Wilkinson's method. Phagocytosis and microbicidal activity assay were performed using Candida albicans as an indicator organism. Nitrobluetetrazolium (NBT) test was used to assess superoxide generation by neutrophils using E. coli endotoxin. RESULTS: The chemotactic activity and phagocytic and microbicidal activity were observed to be significantly reduced (P < 0.01) in LAP neutrophils. On the contrary, superoxide generation was observed to be significantly increased (P < 0.01) in LAP neutrophils compared with healthy individuals. CONCLUSION: The results of the present study suggest that neutrophil functions, namely chemotaxis, phagocytosis and microbicidal activity, are deficient LAP patients. However, superoxide generation was significantly increased when stimulated by endotoxins, which may explain the tissue damage seen in LAP. These abnormal neutrophil functions may predispose to increased susceptibility for LAP. Further large-scale studies are required in the Indian population to ascertain the cause-and-effect relationship of defective host factors and aggressive periodontitis and to develop treatment strategies for more predictable periodontal treatment outcome.

Effect of the probiotic Lactobacilli reuteri (Prodentis) in the management of periodontal disease: a preliminary randomized clinical trial.

OBJECTIVES: The aim of this study was to evaluate the effects of Lactobacilli reuteri (Prodentis) alone and in combination with scaling and root planing (SRP) in a double blind, randomized, placebo-controlled clinical trial of volunteers with chronic periodontitis. METHODS: Thirty, otherwise systemically healthy, chronic periodontitis patients (19 males and 11 females, aged between 34 and 50 years) were included. The study period was 42 days. 'Split-mouth' design was used for the SRP, which was performed on day 0; two quadrants (either right or left) were treated with SRP whereas the remaining two quadrants were left untreated. The participants received a toothbrush, toothpaste, and brushing instructions. L. reuteri Prodentis lozenges (1×10(8) CFU DSM17938+1×10(8) CFU ATCC PTA 5289) or the corresponding placebo lozenges were taken twice daily from day 21 to day 42. Statistical analysis was done for comparisons of clinical parameters (Plaque Index (PI), Gingival Index (GI), Gingival Bleeding Index (GBI), probing pocket depth (PPD), clinical attachment level (CAL)) and microbiological levels of the pathogens Aggregibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi). All p-values less than 0.05 were considered significant. Assessments were made on day 0 before SRP treatment, on day 21 before administration of the lozenges, and on day 42. RESULTS: At day 42, the PI, GI, and GBI were significantly reduced by all treatment modalities. When ranked, the amount of PI, GI and GBI reduction by the different treatments was SRP + Prodentis Prodentis SRP + placebo placebo; all differences were statistically significant. For PPD and CAL, the best result was obtained with the SRP+Prodentis treatment. PPD was reduced from 5.08±0.75 to 3.78±0.61 mm (p<0.001) and CAL from 3.93±0.93 to 2.85±0.74 mm (p<0.001). Prodentis, either alone or following SRP, reduced Aa, Pi, and Pg by 1 log(10) unit (p<0.01). The SRP+placebo combination did not significantly affect the levels of the pathogens. CONCLUSION: The present randomized controlled trial confirms the plaque inhibition, anti-inflammatory, and antimicrobial effects of L. reuteri Prodentis. L. reuteri Prodentis probiotic can be recommended during non-surgical therapy and the maintenance phase of periodontal treatment. Considering the beneficial effects of probiotics, this therapy could serve as a useful adjunct or alternative to periodontal treatment when SRP might be contraindicated. Further studies are required in this direction.

Effect of iron on the survival of Vibrio cholerae in water.

Effect of iron in the form of ferric oxide (Fe2O3) on the survival of V. cholerae O1 was studied. V. cholerae O1 survived for 8 days in plain water whereas in presence of Fe2O3 it survived up to 15 days. Presence of organic material in the water further promoted the bacterial survival by at least 4 days. There was no difference between the behaviour of El Tor and classical biotype. These results indicate that the presence of iron in water could promote the survival of V. cholerae O1 in water and may play a significant role in the epidemiology of cholera.

Copper resistance & its correlation to multiple drug resistance in Salmonella typhi isolates from south Karnataka.

A study was conducted to ascertain the prevalence of copper resistant Salmonella typhi isolates in south Karnataka. Of the 186 strains studied, 26 (13.97%) were found to be copper resistant. Among the copper resistant strains 19 (73.08%) were found multi drug resistant. All copper resistant strains remained uniformly sensitive to ceftriaxone, ciprofloxacin and norfloxacin. Multiple drug resistance was exclusively associated with E1 phage types.

Antimicrobial susceptibility of Salmonella typhi to quinolones & cephalosporins.

Antimicrobial sensitivity testing was carried out for 85 isolates of S. typhi by disc diffusion and microbroth dilution for estimation of minimum inhibitory concentration (MIC). The drugs used included amoxycillin, chloramphenicol, ciprofloxacin, ofloxacin, gentamicin, netilmicin, cefuroxime, ceftizoxime, cefoperazone and ceftazidime. Ninety three per cent of our isolates were resistant to amoxycillin and chloramphenicol but total susceptibility was seen to quinolones and aminoglycosides. We also found that 3 per cent of our isolates were resistant to cephalosporins and 23 per cent were in the intermediate range with an MIC of 12.5 or 25 micrograms/ml to these drugs. In spite of decreased efficacy, the strains continued to be fully susceptible to ciprofloxacin as could be seen from the extended dilutions in microbroth dilution tests. The study also revealed that there was lack of correlation between the two methods of sensitivity testing for cephalosporins. We feel that the development of resistance of S. typhi to third generation cephalosporins is a finding worth consideration for further studies.

Evaluation of laboratory techniques for diagnosis of amoebiasis.

Evaluation of 82 cases of amoebiasis including 4 of liver abscess was done. Microscopy of 62 stool samples revealed trophozoites in 19 (30.6%) and cysts in 8 (12.9%). PVA preserved samples were stained by iron-hamatoxylin and trichrome. Twenty-nine samples (46.7%) were positive by culture on Endamoeba, NIH and Charcoal agar. Additional two culture positive cases were negative by direct microscopy. Three (75%) samples of liver abscess pus were culture positive. Of the sera screened for amoebic antibodies by ELISA, 13 (17.3%) were positive. Stool and blood of healthy controls and 25 gastroenteritis cases were similarly analysed. Of healthy controls one had a high ELISA titre.

Neonatal bacteremia due to high level aminoglycoside resistant (HLAR) enterococci.

A study was conducted to determine the drug resistance pattern of enterococci isolated from cases of neonatal bacteremia. A total of 41 strains of enterococci were isolated of which 35 (85.4%) were Enterococcus faecalis and 6 (14.6%) were Enterococcus faecium. A total of 3 (8.6%) strains of E. faecalis and 2 (33.3%) E. faecium strains showed high level aminoglycoside resistance (HLAR). None of the enterococci tested were vancomycin resistant. Drug resistance was more common among E. faecium strains. All clinically significant isolates of enterococci should be tested for their antibiotic sensitivity pattern including HLAR, and for treatment, antibiotics are selected based on in vitro antibiotic sensitivity test results.

High level aminoglycoside resistance in enterococci isolated from hospitalized patients.

Drug resistance in enterococci isolated from hospitalized patients is reported. Out of 421 strains tested, 45 (10.7%) showed high level aminoglycoside resistance (HLAR). At the species level, 8.2 per cent of Enterococcus faecalis and 33.3 per cent of E. faecium were HLAR. While all the strains of E. faecalis were sensitive to vancomycin, one strain of E. faecium was vancomycin resistant.