Prevalence and severity of periodontal disease at mandibular molar teeth in smokers with regular oral hygiene habits

BACKGROUND: Smoking appears to be detrimental to health because it has been associated with several diseases including cancer and cardiovascular diseases. Smoking also appears to be a major environmental factor associated with periodontal disease progression. The objective of this study was to evaluate the prevalence and severity of periodontal destruction as influenced by smoking in a Thai population. METHODS: Gingival health and periodontal conditions at mandibular molar furcation sites in 120 Thai dental patients (60 smokers and 60 never-smokers, age range 31 to 60 years) with generally high oral hygiene standards and regular dental care habits were evaluated. RESULTS: Smokers exhibited more frequent and severe mandibular molar periodontal destruction than never-smokers. The prevalence and severity of gingival recession, periodontal pocket formation, clinical attachment loss, furcation involvement, and tooth mobility were significantly increased in smokers compared to never-smokers. Seventy-three percent of the smokers exhibited furcation involvement in contrast to only 20% of the never-smokers. CONCLUSIONS: The results of this study suggest that smoking appears to be a major environmental factor associated with accelerated periodontal destruction in adult smokers with generally high oral hygiene standards and regular dental care habits in a Thai population.     

Latex agglutination for rapid detection of Pseudomonas pseudomallei antigen in urine of patients with melioidosis.

A latex agglutination test for the detection of Pseudomonas pseudomallei antigen in urine was evaluated for the rapid diagnosis of melioidosis. With unconcentrated urine, antigen was detected in only 18% of patients with melioidosis overall. However, when urine was concentrated 100-fold, antigen was detected in 47% overall and in 67% of patients with septicaemia or disseminated infection, in whom a rapid diagnosis is most important. The specificity of the test was 100%. These results compared favourably with an enzyme immunoassay. This latex agglutination test is a simple, rapid and highly specific method of diagnosing melioidosis, and will be particularly useful in areas with limited laboratory facilities.     

Accuracy of a commercial IgM ELISA for the diagnosis of human leptospirosis in Thailand

The Leptospira immunoglobulin M enzyme-linked immunosorbent assay (IgM ELISA) has been recommended for the rapid diagnosis of leptospirosis in endemic areas. We conducted a retrospective case-control study of 218 patients (109 leptospirosis cases confirmed by Leptospira culture and/or microscopic agglutination test and 109 control patients with acute febrile illness) to evaluate the diagnostic accuracy of a commercial IgM ELISA (Panbio) in northeast Thailand. Paired serum samples taken on admission and at least 10 days after the onset of symptoms were tested. Using the cutoff value recommended by the manufacturer (11 Panbio units), sensitivity and specificity of IgM ELISA on paired sera were 90.8% and 55.1%. A receiver operating characteristic curve was used to determine the optimal cutoff value. This was 20 Panbio units, which gave a sensitivity and specificity of 76.1% and 82.6%, respectively, on paired sera. We conclude that using either cutoff value, the accuracy of IgM ELISA is limited in our setting.     

Microcirculation and micromorphology of healthy and inflamed gingivae

Inflammation changes the microcirculatory and micromorphological dynamics of human gingiva. Laser Doppler flowmetry (LDF) and a replica technique for scanning electron microscopy (SEM) were used to examine the facial soft tissues of six maxillary anterior teeth, before and after treatment, in 12 patients exhibiting clinically healthy tissues and in 12 others with moderate gingivitis. All patients received oral hygiene instructions and scaling. The gingiva in the gingivitis group became healthy within 3 months after treatment. LDF results were recorded at the free gingivae, interdental gingivae, attached gingivae, and alveolar mucosae of the six maxillary anterior teeth. The gingival blood flows in the gingivitis group before treatment were significantly different from those in the healthy gingiva group. Flows were restored to the same level as the healthy gingiva, with no significant difference, at P 0.01, 3 months after treatment. However, there were significant differences among sites during the same period. In addition, blood flow was reduced to a normal level after the inflammation subsided. Initially, the gingival morphology of the inflamed sites exhibited irregular free gingival margins, in contrast to that of healthy gingivae, which were characterized by rounded margins closely adapted to the tooth. One month post-treatment, the gingivae exhibited a wrinkled appearance, but they had reverted to normal micromorphology by 3 months post-treatment. The replica impression technique can be used to record gingival micromorphology both before and after reduction of inflammation.     

Effectiveness of fixed-dose combination stavudine, lamivudine and nevirapine (GPO-VIR) for treatment of naïve HIV patients in Thailand: a 3-year follow-up

Generic fixed dose combination stavudine (d4T), lamivudine (3TC) and nevirapine (NVP), named GPO-VIR is recommended in the HIV treatment guidelines for Thailand. The long term effectiveness and adverse effects of this drug combination for the treatment of HIV were evaluated in an ambispective study at Bamrasnaradura Infectious Diseases Institute, Nonthaburi Province, Thailand from March 2002 to January 2006. A total of 152 adult treatment naive HIV patients who had received at least 12 months of GPO-VIR were enrolled. The median (IQR) CD4 cell count increased from 23 (8-94) cells/microl at baseline to 126 (38-180), 136 (98-189), 199 (141-255) and 334 (243-414) cells/microl at 3, 6, 12 and 24 months (p < 0.001), respectively. The median (IQR) percentage of body weights increased from baseline by 3.0% (0.3-6.3), 6.2% (2.2-9.3), 7.3% (3.9-10.9) and 8.1% (3.4-11.9) at 3, 6, 12 and 24 months, respectively and then remained at a plateau until the end of the 3-year study. The occurrence of new opportunistic infections decreased significantly (p < 0.001) with GPO-VIR treatment. Drug resistance occurred in 5 cases (3.3%) with a median (IQR) time of 18.0 (16.5-32.5) months to occurrence. Adverse effects included hypercholesterolemia (43.2%), lipodystrophy (35.5%), hypertriglyceridemia (25%), hypertension (13.1%), peripheral neuropathy (11.9%), hyperlactatemia (2.6%) and lactic acidosis (1.3%). Thirty-six patients (27%) switched from GPO-VIR to other anti-retroviral drugs regimens due to lipodystrophy. This study showed GPO-VIR had clinical and immunological benefits, but one-third of patients had adverse effects.     

Immunofluorescence microscopy for the rapid diagnosis of melioidosis.

A direct immunofluorescent antibody test (DIF) was developed for the rapid diagnosis of melioidosis, a potentially fatal infection caused by Pseudomonas pseudomallei. In a clinical evaluation of 369 sputum, pus, or urine specimens from 272 patients with suspected melioidosis, the DIF had a sensitivity of 73% and a specificity of 99% compared with culture. Using this DIF, a confident diagnosis of melioidosis can now be made within two hours of admission to hospital, compared with the delay of two to four days required for culture results. Consequent early institution of specific antimicrobial therapy may help to save lives.     

Efficacy of ivermectin treatment of cutaneous gnathostomiasis evaluated by placebo-controlled trial

Previous studies have revealed that ivermectin treatment for gnathostomiasis can reduce parasitic loads in animals and make recurrent subcutaneous swelling subside in 76% of patients. Our study aimed to evaluate the efficacy of ivermectin for cutaneous gnathostomiasis treatment in a placebo-controlled trial. This study was a prospective randomized placebo-controlled study performed at The Bangkok Hospital for Tropical Diseases, Mahidol University, Thailand. Thirty patients with a serologically confirmed diagnosis of cutaneous gnathostomiasis were enrolled. Seventeen patients in the ivermectin treated group received a single dose of 12 mg ivermectin (200 microg/kg bodyweight), while 13 patients in the control group received a single dose of 40 mg of vitamin B1. The follow-up period was 1 year. Of the 17 patients, 7 (41.2%) responded to ivermectin, while no patient responded to placebo. The mean (95% Cl) time to the first recurrence of subcutaneous swelling with ivermectin and in the placebo groups were 257 (184-331) and 146 (42-250) days, respectively, (p=0.102). Although this study revealed no significant difference in the mean time to first recurrence of swelling between the ivermectin and placebo groups, there was a trend towards ivermectin efficacy against gnathostomiasis in previous animal and human studies. Further studies with different doses of ivermectin and larger sample sizes, and close monitoring for ivermectin tolerability and treatment response are necessary to confirm an efficacy of ivermectin.     

Rapid immunofluorescence microscopy for diagnosis of melioidosis

An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively.     

Prevalence of cytomegalovirus antibodies among various age groups of Thai population

The prevalence of CMV antibody in various groups of Thai population was studied. Pregnant women and young children had been infected with CMV more than the other studied groups. Children of both sex had equal chance of getting CMV infection while the risk of CMV infection in adult between male and female was significantly difference (p < 0.001). Pregnant women had higher chance to get CMV infection than normal women. Prevalence of CMV antibody at present was similar to previous studies.