Campylobacter jejuni antibiotic resistance is rising with a variable geographical pattern; but there is limited data from the Arabian Gulf region. We assessed the sensitivity of human (117) and chicken (33) C. jejuni isolates to erythromycin, ciprofloxacin, tetracycline and trimethoprim-sulfamethoxazole by agar dilution, disc diffusion and the E test. Only 2 human isolates were resistant to erythromycin. In contrast, over 80% of chicken and human isolates were resistant to ciprofloxacin. A significantly higher proportion of chicken isolates than human isolates were resistant to tetracycline, with much higher MIC₅₀ values (P < 0.001). The MIC₉₀ for trimethoprim-sulfamethoxazole by agar dilution was 40 μg/ml. Comparison of the results of the agar dilution method and E test showed 1 major disagreement and 8 minor disagreements for erythromycin, 4 major disagreements for ciprofloxacin and 23 disagreements for tetracycline (19 were major disagreements). This was the first study to describe the pattern of antibiotic resistance in Campylobacter isolates in this region; the results indicate a high degree of erythromycin sensitivity that validates the continued use of this agent as a first-line therapy for Campylobacter enteritis. These findings have wide implications because of the large, highly mobile expatriate population in this setting. In addition, the correlation between agar dilution and disc diffusion supports the use of the latter as an alternative susceptibility testing method for Campylobacter.

We previously reported on the sporadic contamination by Legionella anisa of shower units and sink taps at Ryukyu University Hospital. Starting in July 2003, the neonatal area underwent an 8-month reconstruction, and in March 2005, the boiler system was replaced. We therefore examined shower water and tap water for the presence of Legionella just after replacement of the boiler system. In 3 of the 8 water samples collected from the remodeled area, we isolated Legionella pneumophila serogroup 1 and L. anisa. Moreover, L. pneumophila serogroup 1 was isolated in 4 of the 5 water samples gathered from the unreconstructed area of the same floor. Random amplified polymorphic DNA analysis suggested that a single clone of L. pneumophila might exist throughout the floors of the water distribution system. We replaced the shower units at the Legionella-positive site, and began flushing the sink-faucets with water heated to 55°C for at least 1 h every morning. As a result, Legionella was not subsequently isolated in water samples. In this prospective study, we identified a central contamination by L. pneumophila serogroup 1 and showed that flushing with hot tap water was effective to counter this situation.

Our 2-year study includes research into the occurrence, molecular characteristics, and host risk factors for the carriage of drug-resistant strains of Streptococcus pneumoniae as a continuation of our previous report. From September 2001 to June 2003, strains of S. pneumoniae were isolated from the nasopharynx of children with respiratory tract infection in Soma General Hospital. Of the total of 949 strains, 761 (81%) had a decreased susceptibility to penicillin (MIC > 0.12 μg/ml), while 818 (86%) were resistant to erythromycin (MIC > 1 μg/ml) and 789 (83%) were resistant to clarithromycin (MIC > 1 μg/ml). More than half of the strains had decreased susceptibility to meropenem. Gene analysis of 226 randomly selected strains showed that 200 strains (88.5%) had one or more altered pbp genes and 191 strains (84.5%) had mef(A) and/or erm(B) genes. We reviewed the patient backgrounds for previous antibiotic use, age, daycare attendance, and siblings. Previous use of oral beta-lactams has shown a strong relationship with the carriage of altered pbp genes (P value < 0.01), and previous oral macrolide use has been related to the carriage of macrolide-resistant genes (P value < 0.01). The controlled use of antibiotics might be an important factor in preventing the emergence of S. pneumoniae with antibiotic-resistant genes.

Nontuberculous mycobacteria are often underdiagnosed due to lack of proper diagnostic facilities. To overcome this, we created a rapid PCR method for the species-specific diagnosis of Mycobacterium tuberculosis and its differentiation from other mycobacteria. A set of PCR primers targeting the gene encoding for early-secreted antigen-6 (ESAT-6) of the M. tuberculosis complex was designed and standardized on mycobacterial standard strains and on 75 recent isolates from AIDS patients and 70 isolates from HIV-negative patients seen at the hospital of the All India Institute of Medical Sciences, New Delhi, India. All 145 fresh mycobacterial isolates were identified using phenotypic methods and 16S rRNA PCR followed by sequencing of hypervariable region A. The ESAT-6 PCR detected all of the M. tuberculosis strains correctly (100% sensitivity), but none of the nontuberculous Mycobacterium spp. gave positive results (100% specific). Most nontuberculous mycobacteria were identified in patients with AIDS (24%) followed by those with tuberculous lymphadenitis (12.5%) and those with pulmonary tuberculosis whose treatment had failed (4.3%). The most common nontuberculous mycobacterial species isolated from AIDS patients was M. avium (6.6%), followed by M. fortuitum (5.7%), M. intracellulare and M. terrae (2.6% each). M. celatum, M. duvalii, M. austroafricanum, M. phlei and M. flavescence were also isolated from one patient each. The combination of genus-specific PCR primers with the novel ESAT-6 primer set could provide accurate and rapid diagnosis of mycobacteriosis.

A sensitive methodology for PCR detection of Staphylococcus aureus or Bordetella pertussis DNA within cot mattress polyurethane foam was developed. The assay’s applicability was evaluated on polyurethane foam from used cot mattresses. S. aureus DNA was detected in 42% of mattresses of sudden infant death syndrome (SIDS) victims and 29% of comparison group (no death) mattresses tested. B. pertussis DNA was detected in 50% of SIDS mattresses and 27% of comparison group mattresses. There was no significant statistical association between SIDS cases and the presence of S. aureus or B. pertussis DNA in cot mattress polyurethane.

We evaluated the effects of special oral care using a toothbrush with combined irrigation and suctioning functions, along with povidone-iodine to treat oral bacteria and mucositis, in esophageal cancer patients undergoing chemoradiotherapy. In the special care group, oral hygiene was performed 3 days a week after dinner. Bacteria in saliva and plague samples were measured at various sampling points after chemoradiotherapy. The incidence of mucositis was significantly reduced in the special care group in comparison with the control group. Total streptococci were significantly decreased in the opportunistic pathogens-positive and lower-level mutans streptococci control group during chemoradiotherapy, but they were not reduced in the opportunistic pathogens-negative and higher-level mutans streptococci control groups or in the special care group. Our results showed that a special oral care regimen enabled the total population of streptococci microflora to remain stable, was negatively correlated with opportunistic pathogens and positively correlated with mutans streptococci infection, and prevented the development of mucositis.

Identification of hepatitis C virus (HCV)-RNA in blood serum is crucial for hepatitis C diagnosis and for appropriate treatment. Detection of HCV-RNA in blood serum is used for therapy monitoring of patients with hepatitis C. Despite HCV-RNA elimination from blood serum during treatment in some patients, HCV viremia appears again after the completion of therapy. The aim of this study was to assess HCV-RNA in peripheral blood mononuclear cells (PBMCs) of hepatitis C patients in relation to HCV-RNA and antibodies to HCV in the serum. The study involved 71 patients undergoing anti-viral therapy (interferon and ribavirin). RNA isolated from serum and PBMCs was examined for the presence of HCV-RNA by an RT-PCR technique using specific oligonucleotide primers or by commercially available kits. In order to show the possible presence of HCV sequences in PBMCs, molecular DNA probes were constructed with a PCR amplicon and biotin-labelled by nick translation, and FISH and extended chromatin fibers in situ hybridization (ECFs-FISH) techniques were used. A 24-month follow-up study revealed that 34 out of 59 patients (58%) eliminated HCV-RNA from their sera. In the serum negative group, HCV-RNA was detected in PBMCs of 2 patients. The presence of HCV-RNA in PBMCs was confirmed by the FISH technique. In the ECFs-FISH procedure, no signal was found in all examined patients. Our data suggest that PBMCs infected with HCV can serve as a virus reservoir. HCV-RNA serum negative patients who have HCV-RNA in their leukocytes after completion of anti-viral therapy would be at great risk of hepatitis C recurrence. These HCV-RNA serum negative but PBMCs positive patients would be a potential source of HCV spread.

To investigate the details of the pathophysiology of endogenous fungal endophthalmitis (EFE), we performed sequential histological and ophthalmoscopic examination on a rabbit model comparing immunocompromised EFE developed using a steroid with an immunocompetent one intravenously inoculated with Candida albicans. The ophthalmoscopic examination and histological analysis of the retina in both groups demonstrated that lesions appear on the equator of the eyeball and then spread toward the posterior pole. It has been speculated that, because of the unique innate vasculature system of the equator, there is a sudden, decrease of shear stress in rheologically, resulting in adhesion of yeast cells to the endothelial cells. Histological examination revealed that the degree of polymorphonuclear leukocyte (PMN) infiltration was equivalent in the two groups. However, the appearance of PMN was delayed and the number of fungi was higher in the state of hyphae and/or pseudohyphae in the steroid-treated group. Furthermore, the eyeball was found to be the second earliest organ involved in candidemia. Our results indicate that ophthalmic examination is useful to monitor the development and systemic involvement of endophthalmitis in patients with candidemia.

We retrospectively reviewed 122 patients with culture-proven bacterial brain abscesses (BBA) at our hospital over a period of 20 years and identified seven fusobacterial brain abscess patients. Here we describe the therapeutic experience in fusobacterial BBA cases and compare the clinical features of patients with single pathogen infection between fusobacterial and non-fusobacterial brain abscesses. Fusobacterium spp. Accounted for 6% of the implicated pathogens of monomicrobial BBA. All seven fusobacterial brain abscess patients contracted the infection spontaneously, and two cases had important preceding events. F. nucleatum was the commonest one of the species described. Clinical presentations and laboratory data of these seven patients were similar to those of non-fusobacterial BBA, and in these patients the diagnosis was only confirmed by positive culture results. All seven patients were successfully treated with combined surgical and antimicrobial therapy. Although the average age tends to be older and there is a higher prevalence of multiloculated brain abscesses in patients with this type of BBA, the therapeutic outcome can be favorable with early diagnosis and prompt treatment.

We constructed a pair of Nocardia-Escherichia coli shuttle vectors, pNV18 and pNV19, by combining the mycobacterial plasmid pAL5000 with the E. coli vector pK18 or pK19. These vectors have a number of useful features, including small size (4.4 kb), a multiple cloning site, and blue/white selection. To our knowledge, pNV18 and pNV19 are the first cloning vectors for practical use in Nocardia spp.

This report presents the case of a patient associated with a Streptococcus pneumoniae isolate that was resistant to a new ketolide antibiotic, telithromycin (minimum inhibitory concentration: 4 μg/ml). The patient, a 61-year-old female with bronchiectasis, was treated with 200 - 400 mg of clarithromycin daily for 6 years until the isolation of the resistant strain but without prior exposure to telithromycin. The strain was isolated from her sputum but not from the nasopharynx. This isolate carried erm(B) and had mutations in 23S rRNA and riboprotein L4. To our knowledge, this is the first case report concerning a telithromycin-resistant S. pneumoniae isolate in Japan by mutation in L4. Although the long-term clarithromycin administration may have contributed to the induction of resistance in this patient, this could not be confirmed, since S. pneumoniae was not isolated until the present episode.

Tularemia caused by Francisella tularensis, which is considered a biological warfare agent, is a widely distributed zoonosis. In this study, we aimed to compare a 2005 outbreak of tularemia that was confirmed as waterborne by PCR to outbreak of tularemia that was reported as waterborne in 2000 and to investigate the changes of epidemiological characteristics between these two outbreaks occurring in the same region. In the present study, a total of 11 patients were diagnosed with tularemia. In the 2000 outbreak, oropharyngeal type was observed in 19 patients, and ulceroglandular type in 3 patients. In the 2005 outbreak, oropharyngeal type was observed in 8 patients, and oculoglandular type in 3 patients. However, our cases are not sufficient to make a conclusion that the characteristics of tularemia seem to be changing.

We examined the incidence of amantadine-resistant influenza AH3 viruses isolated in Nara Prefecture during the 2005 - 06 winter season. The genetic analyses of the M2 ion channel protein were conducted using reverse transcriptase PCR and direct sequencing. Thirteen out of 18 (72.2%) strains were identified as amantadine-resistant, and this incidence was remarkably higher than those previously recorded in Nara Prefecture. Genetic analyses of the viruses revealed that all the anti-drug strains contained a change at position 31 (AGT→AAT, Ser31Asn) in the M2 gene. One of the 13 amantadine-resistant strains also contained a change at position 27 (GTT→GCT, Val27Ala). Our data indicate that there has been a significant increase of drug-resistant influenza AH3 viruses in Nara Prefecture, and raise concern about the spread of resistant influenza AH3 viruses in Japan.

It is difficult and time-consuming to distinguish Haemophilus influenzae from the genotypically similar Haemophilus parainfluenzae, which is a commensal of the human oral cavity. The novel nucleic acid amplification technique of loop-mediated isothermal amplification (LAMP), which amplifies DNA under isothermal conditions (63°C) with high specificity, efficiency, and rapidity, was evaluated for H. influenzae detection. A H. influenzae-specific LAMP primer set was designed for the outer membrane protein P6 gene. Primer set specificity was validated using 4 Haemophilus spp. and 13 other species. Within 60 min, LAMP detected 100 or more copies of purified DNA with a sensitivity that was 10-fold higher than that of conventional PCR. This method can be used to differentiate H. influenzae from H. parainfluenzae strains. Thus, LAMP may represent a sensitive and reliable means of diagnosing H. influenzae infection.

Japanese spotted fever (JSF) is caused by Rickettsia japonica. Although it induces a variety of complications, acute myocarditis has never been reported as a complication of JSF. We treated a JSF patient who developed acute myocarditis. To our knowledge, this is the first case of JSF complicated with acute myocarditis.