Bacteriological evaluation of tonsillar microbial flora according to age and tonsillar size in recurrent tonsillitis.

Although numerous studies based on the bacteriology of the tonsil have been carried out, none of them analyzed the variation of tonsillar flora with respect to both age and tonsillar size. The purpose of this study was to isolate the facultative and obligate anaerobes both from the surface and the core of tonsils in recurrent tonsillitis as well as to analyze the variation of isolated bacterial strains according to age and tonsillar size. A prospective study was performed on 111 patients who underwent tonsillectomy. We analyzed the differences between the bacterial pathogens in recurrent tonsillitis and semi-growth estimates with regard to age and tonsillar grade. Among 111 cases, 604 bacterial strains of 21 different from the tonsil superficial and core were isolated. The most common facultative anaerobic species isolated from the surface and core were Coagulase-negative staphylococci, Alpha-hemolytic streptococci and Diphtheroid bacilli in all subgroups except patients below 8 years old. The most commonly obligate anaerobic species isolated from the core were Propionibacterium acnes, Prevotella melaninogenica and Peptostreptococcus anaerobius. We found no significant difference in the cultured bacteria with respect to age and tonsillar size. The study subgroups did not differ in the occurrence of semiquantitative growth estimates of 3-4+. Our study demonstrates that there is polymicrobial aerobic and anaerobic flora in tonsils with regardless of patient's age and tonsillar size. This polymicrobial spectrum of bacteria may contribute to recurrence and to the failure of conservative treatment of these cases and therefore leads to surgical therapy.

The detection of occult HBV infection in patients with HBsAg negative pattern by real-time PCR method.

AIM: Diagnostic problems may be encountered in Hepatitis B virus (HBV) infections by serological tests and HBV DNA can be detectable in plasma and liver tissue while the HBsAg test is negative. This situation can be defined as occult or isolated Anti-HBc infections. Occult HBV infections may be divided into two categories by using hepatitis markers. One of them being that all hepatitis markers are negative and the other situation is having Anti-HBc +/- and Anti-HBs+patterns. These situations can be seen in isolated Anti-HBc cases. METHOD: In this study, we aimed to detect the ratio of occult HBV infections by investigating HBV DNA in four different groups. These groups are: (1) 20 isolated Anti-HBc positive individuals, (2) 23 individuals naturally immune to HBV infection, (3) 20 individuals with seronegative hepatitis markers and high ALT levels, and (4) 23 vaccinated individuals against HBV. In order to detect HBV DNA the real-time PCR kit (QIAGEN, Artus HBV RG PCR Kit, Germany) with high analytical sensitivity (≤3.8IU/ml) was used. RESULTS: The reliability of the molecular methods was assessed by increasing the quantitation standards of internal, external and also positive controls. No HBV DNA was detected in any of the 86 individuals consisting of four study groups. CONCLUSION: In conclusion, we did not detect occult HBV infection in our four study groups by using a high sensitivity real-time (RT) PCR method, while occult HBV infections with various frequencies were detected in other large, serial international studies in which highly sensitive analytical molecular methods were used. Although we also used a high standard molecular kit to detect occult HBV infections, we suggest that the reason for the absence of detection of occult HBV infections may be due to the small number of cases included in this study. However, it was assumed that the use of a nucleic acid amplification technology (NAT) with high analytical sensitivity in blood banks to prevent HBV transmission by blood transfusion is controversial due to both costs and diagnostic efficacy and for this reason we suggest that it will be useful to perform large serial studies regarding occult HBV infections in the future.

The importance of transmission time in HIV infections and an epidemiological prospective follow-up study for 1 year in the Marmara Region of Turkey.

It is important to detect recent and new HIV/1 infections and to take preventative measures in order to prevent rapid disease progression in AIDS and to decrease the incidence of infection. We aimed to detect long standing or recent HIV infections by determining transmission times for the cases in which first-time HIV/1 seropositivity were detected. The serum samples of 323 cases which were found to be seropositive by ELISA and Western-blotting were included in this study. The discrimination between long-term and recent HIV/1 infection was made by determining transmission-time with the Aware BED-EIA, HIV-1 incidence test (IgG capture HIV-EIA) tests. Ninety-six healthy blood donors who did not have a positive anti-HIV test and a chronic infectious disease for at least 1 year were included in this study as a negative healthy control group. In the discrimination of long-term and recent HIV/1 infections, only in vitro ODn values were used. The cases with normalized optical density (OD) (OD(specimen)/OD(calibrator))<0.8 by commercial kit were accepted as recent HIV infection (155 days history or seroconversion less than 6 months). The cases with ODn >1.2 were accepted as long-term HIV/1 infections (more than 155 days history or more than 6 months). The cases with ODn between 0.8 and 1.2 were accepted as "additional tests needed" cases. We detected recent HIV/1 infections (<6 months) in 60 (18.5%) out of 323 cases and long-term HIV/1 infections (>6 months) in 263 (81.5%) out of 323 cases. The most frequently encountered transmission route in long-term and recent HIV/1 infections was heterosexual sexual intercourse as 54 (50%) and 257 (97%), respectively. 63.3% of newly infected patients were married females and 65.3% of recently infected patients were males. In conclusion, the detection of the high ratio of long-term HIV/1 infection cases (81.5%) compared to recent infections (18.5%) suggested to us, that the long standing cases may have some activities related with transmission of HIV/1 in the past. The detection of higher HIV/1-infections in individuals which had heterosexual sex and also in married males suggested that this situation poses a very great threat for the health of society.

Oropharyngeal flora changes after tonsillectomy.

OBJECTIVE: We aimed to investigate the effect of tonsillectomy on oropharyngeal flora in children who underwent tonsillectomy for chronic recurrent tonsillitis. STUDY DESIGN AND SETTING: A prospective study was performed comprising patients with chronic recurrent tonsillitis who underwent tonsillectomy at the Department of Otolaryngology, Cerrahpasa Medical School. Incisional core biopsies of excised tonsils were also performed. Swabs and core biopsy specimens were transferred and maintained in Stuart's medium and sent to the Department of Microbiology and Clinical Microbiology at Cerrahpasa Medical School for microbiologic evaluation. SUBJECTS AND METHODS: Oropharyngeal swabs and tonsillar core biopsy specimens from 31 patients operated on for recurrent tonsillitis were cultured. Follow-up oropharyngeal swabs were cultured one month after tonsillectomy. RESULTS: There was no significant difference between the preoperative and postoperative isolation rate of the potentially pathogenic bacteria. Normal aerobic flora did not change significantly. However, the isolation rate of the Neisseria species dropped (P = 0.097) but did not reach statistical significance. Among anaerobes, Bacteroides fragilis, one of the major anaerobic bacteria, dropped significantly (P = 0.007). The Propionibacterium acnes isolation rate increased significantly (P = 0.009). CONCLUSION: Oropharyngeal anaerobic bacterial flora decreases after tonsillectomy in recurrent tonsillitis patients. The isolation rate for bacteria of the normal flora and potentially pathogenic bacteria does not change. Tonsils with recurrent infections may become a nidus for anaerobic bacteria. In patients with chronic recurrent tonsillitis, tonsillectomy may help change anaerobic bacterial oropharyngeal flora to the normal flora found in healthy individuals.

Lymphocyte subgroups and natural killer cell activity in recurrent herpetic stromal keratitis.

PURPOSE: Although the role of natural killer cells in the defense against certain viral infections has been published, little is known about the role of lymphocyte subgroups in recurrent herpetic stromal keratitis. Accordingly, serum levels of major immunoglobulins (IgG, IgA, and IgM) and IgG subgroups, the lymphocyte subgroups, and natural killer cell activity were investigated in patients with recurrent herpetic stromal keratitis. METHODS: Eleven patients with recurrent herpetic stromal keratitis and 10 healthy subjects were included. A delayed-type hypersensitivity skin test was performed in addition to the determination of serum immunoglobulin levels, IgG subgroups, peripheral blood lymphocyte percentages, and natural killer cell activity in both groups. RESULTS: The result of the delayed-type hypersensitivity skin test was positive in all patients with recurrent herpetic stromal keratitis and healthy subjects. No significant difference was obtained in serum immunoglobulin levels and IgG subgroups between the patients and healthy subjects. Among the cell surface antigens (CD3, CD4, CD8, CD16, CD19, and CD20), only CD8+ (i.e., cytotoxic) T-lymphocyte percentages were significantly increased (P=0.003), and the CD4:CD8 ratio was significantly decreased in the patients compared to the healthy subjects (P=0.021). There was no significant difference in the expression of CD16+ natural killer cells between both groups, despite a significantly lower natural killer cell activity in patients with recurrent herpetic stromal keratitis (P=0.011). CONCLUSIONS: These results indicate that human cytotoxic T cells show a difference in numbers and natural killer cell activity that may affect the prognosis of recurrent herpetic stromal keratitis.

Haemophilus influenzae type b antibodies in vaccinated and non-vaccinated children.

BACKGROUND: Invasive Haemophilus influenzae type b (Hib) infection has a high morbidity among young children, but the burden of disease and rate of Hib are different in different regions. The aim of the present study was to investigate the levels of Hib antibodies and the oropharyngeal Hib prevalence in young children. METHODS: One hundred-fifty nine healthy children aged 19-36 months of age were included in this cross-sectional study. Anti-polyribosylribitol phosphate (anti-PRP) antibody concentrations were measured using commercially available enzyme-linked immunosorbent assay (ELISA), and serotyping of isolated Hib strains was conducted by slide agglutination with specific antisera. RESULTS: Of the study participants, 57 (35.8%) were fully vaccinated (group 1A); 17 (10.7%) were incompletely vaccinated (group 1B), and 85 (53.5%) were non-vaccinated (group 2). Geometric mean titer (GMT) of anti-PRP antibody was 3.8 microg/mL, 2.2 microg/mL and 0.49 microg/mL in group 1A, group 1B and group 2, respectively. While all children in group 1 (n = 74) had seroprotective antibody concentrations (>/=0.15 microg /mL), of the children in group 2 (n = 85) 31.8% did not have seroprotective anti-PRP levels (P < 0.0001). A total of 68.2% in group 2 had natural immunity. Nineteen children (33.3%) in group 1, and 46 (54.1%) in group 2 had oropharyngeal Hib colonization (P = 0.0004). CONCLUSIONS: Hib conjugate vaccine is immunogenic and reduces Hib colonization. Each country should investigate the burden of Hib disease and the natural immunity in young children, and should determine antigenic dose, number of doses administered and dose intervals before deciding whether to introduce Hib conjugate vaccine in routine immunization programs.

Pharyngeal carriage and antimicrobial resistance of Haemophilus influenzae in non-type-b-vaccinated healthy children attending day care centers in Turkey.

BACKGROUND: The true prevalence of Haemophilus influenzae carriage rates in Turkey is unknown. As surveillance of pharyngeal carriage of resistant strains is important for initiating adequate empirical antimicrobial therapy, with the present study, we aimed to determine the carriage rates and antimicrobial resistance patterns of H. influenzae isolated from healthy children attending day care centers (DCCs) in Istanbul, Turkey. METHODS: A total of 195 healthy children were included from two DCCs. Pharyngeal swabs were cultured for H. influenzae which were identified according to standard microbiologic procedures. Antimicrobial susceptibility tests were performed by the agar dilution method in accordance with the guidelines of the National Committee for Clinical Laboratory standards. beta-Lactamase production was determined by the nitrocefin disc test. RESULTS: The average pharyngeal carriage rate of H. influenzae was determined as 48.7%: 7.2% type b, 7.6% other capsulated strains, 33.9% noncapsulated strains, with a carriage peak between 0 and 11 months (68.1%). The ampicillin resistance observed in 7.3% of H. influenzae isolates was associated with a presence of beta-lactamase, except for one isolate which was interpreted as beta-lactamase-negative ampicillin-resistant strain. The resistance of H. influenzae to sulbactam/ampicillin, cefuroxime, azithromycin, tetracycline and cotrimoxazole was 0.5, 1.5, 0.5, 2.9 and 28.6%, respectively. Cefotaxime, ceftriaxone, ciprofloxacin and imipenem resistance was not detected. CONCLUSION: Our data show that the upper respiratory tract of about 48.7% of children was colonized with H. influenzae. This high colonization rate indicates that there is a need for surveillance of pharyngeal carriage of resistant strains in healthy Turkish children attending DCCs.

Microbial changes in conjunctival flora with 30-day continuous-wear silicone hydrogel contact lenses.

PURPOSE: To determine the effect of 30-day continuous-wear silicone hydrogel contact lenses on the conjunctival flora in asymptomatic wearers. METHODS: The authors studied 29 eyes of 15 patients wearing Focus NIGHT & DAY silicone hydrogel contact lenses for up to 30 nights of continuous wear. The average age of the patients was 25.54 +/- 8.98 years. Cultures of the inferior cul-de-sac were taken bilaterally from all eyes, before and after lens wear in asymptomatic patients. The isolation and identification of bacteria were made by standard clinical laboratory methods. RESULTS: The number of eyes whose conjunctival cultures were sterile before using the lenses significantly decreased (P = 0.0005), and the number of eyes with a growth of coagulase-negative staphylococci and diphtheroid rods in their conjunctival cultures significantly increased after using these lenses (P = 0.001 and P = 0.031, respectively). Conversely, a statistically significant difference was not found in the number of eyes that carried Propionibacterium acnes and Fusobacterium nucleatum in their conjunctival cultures before and after using the 30-day continuous-wear silicone hydrogel lenses (P = 0.998 and P = 0.488, respectively). CONCLUSIONS: The results suggest that the sterility of the conjunctiva significantly decreased after using 30-day continuous-wear silicone hydrogel contact lenses. In addition, the number of bacteria of the normal conjunctival flora significantly increased after the use of these lenses. Contamination by the bacteria of the eyelids may be a possible colonization factor in this study group. Therefore, it is appropriate to examine the patients who wear these lenses more frequently.

Mobiluncus species in gynaecological and obstetric infections: antimicrobial resistance and prevalence in a Turkish population.

The purpose of this study was to determine the prevalence and antimicrobial resistance of Mobiluncus species isolated from specimens collected from Turkish women with gynaecological infections. Mobiluncus species were isolated on enriched Schaedler agar and RLK agar plates under anaerobic conditions. The MICs of various antibiotics were evaluated using an agar dilution procedure. The prevalence of Mobiluncus species isolated from vulvo-vaginal abscesses, endometrial smears, salpingitis and bacterial vaginosis was 2%, 4.7%, 3.8% and 49%, respectively. Mobiluncus isolates were only resistant to metronidazole (81% resistance). The isolation rate of M. curtisii was higher than M. mulieris in Turkish women with bacterial vaginosis, vulvo-vaginal abscesses, endometritis or salpingitis.

Antimicrobial resistance and beta-lactamase production of clinical isolates of prevotella and porphyromonas species.

BACKGROUND: This study determined the beta-lactamase production and the antimicrobial resistance of 72 Prevotella species and 48 Porphyromonas species isolated from different clinical specimens. METHODS: All strains were identified using API 32 ID. The beta-lactamase production was determined by nitrocefin disks. E test strips of benzylpenicillin, ampicillin + sulbactam, cefoxitin, clindamycin, metronidazole and imipenem were tested for each strain. RESULTS: Nineteen Prevotella melaninogenica, 18 Prevotella intermedia, 16 Prevotella denticola, 11 Prevotella loescheii and 8 Prevotella bivia strains were identified. Four were clindamycin resistant. The highest beta-lactamase production was found at a rate of 68.4% in P. melaninogenica species. Additionally, 33 Porphyromonas asaccharolytica and 15 Porphyromonas gingivalis strains were identified. None of them produced beta-lactamase. CONCLUSION: In view of the emerging antibiotic resistance among anaerobes, the current local susceptibility profile of our Prevotella and Porphyromonas species will establish the basis for additional surveys tracing significant changes in the antimicrobial resistance of our clinical isolates.

Microbiologic evaluation of frequent-replacement soft contact lenses.

PURPOSE: This article reports a microbiologic study of two kinds of monthly frequent-replacement daily wear soft contact lenses, with different amounts of water content, in asymptomatic contact lens wearers. METHOD: We studied 35 lenses of 18 patients who wear frequent-replacement soft contact lenses with a water content of 38% and 40 lenses of 20 patients using frequent-replacement contact lenses with a water content of 55%. The lenses worn by patients regularly for 1 month were removed from their eyes in a sterile manner on the 30th day and were studied microbiologically to isolate pathogenic agents. RESULTS: In the group of monthly frequent-replacement soft contact lenses with a water content of 38%, microorganisms were isolated at a rate of 91%; and in the group of monthly frequent-replacement soft contact lenses with a water content of 55%, microorganisms were isolated at a rate of 85%. When the two groups were compared, there was no statistically significant difference (P=0.31). Although coagulase-negative staphylococci, Corynebacterium spp, and gram-negative rods were detected in both groups, Staphylococcus aureus, non-hemolytic streptococci, Neisseriae spp, and Penicillium spp also were isolated in the group with the higher water content. CONCLUSION: Bacteria spreading from the environment or from skin flora to the eyes showed more diversity in the group of frequent-replacement soft contact lenses with a high water content. Additionally, Penicillium spp also was isolated in this group. Therefore scrupulous attention to daily lens care is crucial for people who wear frequent-replacement soft contact lenses.