C. Coulter

Clonal strains of Pseudomonas aeruginosa in paediatric and adult cystic fibrosis units

Despite recent reports of clonal strains of Pseudomonas aeruginosa in cystic fibrosis (CF) units, the need for routine microbiological surveillance remains contentious. Sputum was collected prospectively from productive patients attending the regional paediatric and adult CF units in Brisbane, Australia. All P. aeruginosa isolates were typed using pulsed-field gel electrophoresis. Spirometry, anthropometrics, hospitalisations and antibiotic sensitivity data were recorded. The first 100 sputum samples (first 50 patients at each clinic) harboured 163 isolates of P. aeruginosa. A total of 39 patients shared a common strain (pulsotype 2), 20 patients shared a strain with at least one other patient and 41 patients harboured unique strains. Eight patients shared a strain identical to a previously reported Australian transmissible strain (pulsotype 1). Compared with the unique strain group, patients harbouring pulsotype 2 were younger and had poorer lung function. Treatment requirements were similar in these two groups, as were the rates of multiresistance. In conclusion, 59% of patients harboured a clonal strain, supporting the need for routine microbiological surveillance. In contrast to previously described clonal strains, the dominant pulsotype was indistinguishable from nonclonal strains with respect to both colonial morphology and multiresistance. The clinical significance of clonal strains remains uncertain and requires longitudinal study.

Burkholderia pseudomallei: another emerging pathogen in cystic fibrosis

Background:Burkholderia pseudomallei is an important cause of acute fulminant pneumonia and septicaemia in tropical regions of northern Australia and south east Asia. Subacute and chronic forms of the disease also occur. There have been three recent reports of adults with cystic fibrosis (CF) who presumably acquired B pseudomallei infection during extended vacations or residence in either Thailand or northern Australia. Methods: The clinical course, molecular characteristics, serology and response to treatment are described in four adult CF patients infected with B pseudomallei. Polymerase chain reaction (PCR) based methods were used to confirm B pseudomallei and exclude B cepacia complex. Genotyping was performed using randomly amplified polymorphic DNA (RAPD) PCR and pulsed field gel electrophoresis (PFGE). Results: Four patients are described with a mean duration of infection of 32 months. All but one patient lived in tropical Queensland. Two patients (with the longest duration of infection) deteriorated clinically and one subsequently died of respiratory failure. Both responded to intravenous treatment specifically targeting B pseudomallei. Another patient suffered two severe episodes of acute bronchopneumonia following acquisition of B pseudomallei. Eradication of the organism was not possible in any of the cases. PFGE of a sample isolate from each patient revealed the strains to be unique and RAPD analysis showed retention of the same strain within an individual over time. Conclusions: These findings support a potential pathogenic role for B pseudomallei in CF lung disease, producing both chronic infection and possibly acute bronchopneumonia. Identical isolates are retained over time and are unique, consistent with likely environmental acquisition and not person to person spread. B pseudomallei is emerging as a significant pathogen for patients with CF residing and holidaying in the tropics.

Epidemiological analysis of methicillin-resistant Staphylococcus aureus isolates from adult patients with cystic fibrosis

Using pulsed-field gel electrophoresis, we genotyped 21 methicillin-resistant Staphylococcus aureus isolates from patients attending an adult cystic fibrosis unit. Eleven patients exhibited pulsotypes related to 2 locally endemic strains. Eleven chronically colonized patients were assessed over a period of up to 2 years, and all demonstrated a retention of strain type.

Extensively Drug-Resistant Tuberculosis, Central China, 2007–2009

To the Editor: Multidrug-resistant (MDR) tuberculosis (TB), defined as TB caused by Mycobacterium tuberculosis resistant to isoniazid and rifampin, is threatening global control of TB. The emergence of extensively drug-resistant (XDR) TB, defined as MDR TB resistant to at least 1 quinolone and 1 of 3 injectable second-line drugs (kanamycin, amikacin, or capreomyin), further jeopardizes TB control and prevention. In the People’s Republic of China, a country in which the economic cost of TB is high, incidence of MDR TB is higher (10%) (1) than the average global incidence (4.8%) (2). Published reports of XDR TB prevalence indicate that XDR TB is probably an underestimated problem in mainland China (3–7). China is a geographically large country, and the characteristics of drug resistance of TB might vary among provinces (2). Five regional surveys reported drug-resistance patterns of XDR TB in mainland China, and 3 were conducted in eastern China (3–7). To determine prevalence of XDT TB in central China, we characterized the resistance of MDR M. tuberculosis to second-line drugs, specifically identifying XDR strains, in Henan, a major province of central China. Henan Province has the country’s third largest provincial population (94 million) and high rates of drug resistance to any agent (35.5%) (2). The bacterial population retrospectively analyzed in this study has been described (8). In brief, from 2007 through 2009, clinical isolates were collected consecutively by the Henan Center for Disease Control and Prevention TB surveillance system and screened for resistance to 4 first-line drugs. Proportion method–based drug susceptibility testing was conducted for the following critical concentrations: isoniazid 0.2 μg/mL, rifampin 40.0 μg/mL, ethambutol 2.0 μg/mL, and streptomycin 4.0 μg/mL. As a result of that study, 150 MDR TB isolates from TB patients were obtained. The genotyping of all MDR isolates was identified by variable number tandem repeat of mycobacterial interspersed repetitive units based on 16 loci with high discriminatory power. For the study reported here, we performed additional drug susceptibility testing of 4 second-line drugs at the Henan Center for Disease Control and Prevention TB reference laboratory. We used the Lowenstein-Jensen proportion method, recommended by the World Health Organization, according to the following critical drug concentrations: ofloxacin 3.0 μg/mL, kanamycin 30.0 μg/mL, amikacin 30.0 μg/mL, and capreomycin 40.0 μg/mL (9). Susceptibility results for all second-line drugs tested were reported for 143 (95.3%) of 150 MDR M. tuberculosis isolates. Among these 143 isolates, 49 (34.3%) were resistant to ofloxacin, 23 (16.1%) to kanamycin, 17 (11.9%) to amikacin, and 25 (17.5%) to capreomycin (Table). All 17 amikacin-resistant isolates were also resistant to kanamycin, and 16 were also resistant to capreomycin. Also among the 143 MDR isolates, 18 (12.6%) showed resistance to ofloxacin and at least 1 second-line injectable drug and were defined as XDR strains. All 18 XDR M. tuberculosis isolates were resistant to isoniazid, rifampin, streptomycin, and ofloxacin; 14 (77.8%), 16 (89.9%), 12 (66.7%), and 17 (94.4%) were resistant to ethambutol, kanamycin, amikacin, and caperomycin respectively. Twelve amikacin-resistant XDR isolates were also resistant to kanamycin and capreomycin (Table). Table Second-line drug resistance patterns for 143 strains of multidrug-resistant tuberculosis, Henan Province, China, 2007–2009* Genotyping results demonstrated that XDR strains were distributed diversely in the phylogenetic tree, suggesting that these strains evolved independently. Our results indicated that 12.6% of MDR TB isolates from Henan Province meet the definition of XDR TB, which is less than that found by hospital-based studies performed in Shandong (18.7%), Shanghai (30.0%), and Beijing (14.9%) (3,5,6) but higher than that found by 2 other studies conducted in Beijing and Shanghai (6.3% each) (4,7). The discrepancy between the percentages of XDR TB and MDR TB strains found in these studies might be explained by the probable inclusion of patients who had been previously treated and patients with chronic TB. Previous studies found high cross-resistance among all 3 second-line injectable drugs in MDR and XDR TB strains (5,10). Our results support these observations; capreomycin resistance of MDR and XDR strains (17.5% and 94.4%, respectively) in Henan Province were higher than the average levels (10.2%, 62.5%, respectively) reported by a worldwide study (10). Pyrazinamide is an essential drug recommended by World Health Organization guidelines for treatment of MDR TB. Among the population with MDR TB that we studied, 10 (76.9%) of 13 XDR isolates were sensitive to pyrazinamide (data not shown), suggesting that pyrazinamide is still an effective first-line anti-TB drug for most XDR TB patients in Henan Province. We restricted our investigation to 1 province. However, given the average national prevalence of XDR TB (8% of MDR TB) (1) and the magnitude of the population of Henan Province, our findings indicate that the prevalence of XDR TB might be higher in central China than previously documented.

A case series of medically managed infective endocarditis after transcatheter aortic valve replacement

Abstract We report a series of 4 cases of transcatheter aortic valve replacement infective endocarditis from our institution. Atypical diagnostic features were noted echocardiographically. Infection with enterococcal species was prevalent and a coexisting mitral valve vegetation was found in 2 patients. All 4 patients had excellent responses to intravenous antibiotics.

Endocarditis after Use of Tongue Scraper

To the Editor: Tongue scraping is advocated as a therapy for managing halitosis and as a technique for preventing dental caries by reducing bacterial counts in the mouth (1). The practice has been in existence for centuries (2). A Cochrane review has concluded that tongue cleaning is marginally and temporarily more effective than use of a toothbrush in reducing a measurable marker for halitosis, exhaled volatile sulfur compounds (3). The use of tongue scrapers may not be limited to those with clinical halitosis, as 10%–30% of Americans report bad breath (4), and websites offer to solve the problem of “your bad breath” for a price. We report the case of a woman in whom infective endocarditis followed the use of a tongue scraper. A 59-year-old woman with a known history of mitral valve prolapse with associated valvular regurgitation had onset of progressive malaise, fever, sweats, myalgia, and headache; the symptoms lasted 10 days. Two months previously she had begun cleaning her tongue with a plastic tongue scraper purchased at her local pharmacy. She had not undergone recent dental work. Her medical background included migraines, hypertension, mild quiescent psoriasis, and previous depression. Her medications were venlafaxine and candesartan. When seen at her local hospital, she reported severe headache and myalgia, with fever. The same day, she had a rigor at home and reported chest tightness and mild dyspnea. Physical examination showed no focal findings other than the mitral valve prolapse. A provisional diagnosis of bacterial meningitis was made. Emergency treatment comprised intravenous dexamethasone, ceftriaxone, and benzylpenicillin. Cerebrospinal fluid analysis performed shortly after showed no cells and normal glucose and protein levels. Culture of the cerebrospinal fluid was negative. No further antimicrobial agents were administered. Multiple blood cultures were drawn but remained culture negative. Serologic tests for Q fever, Bartonella spp., and endemic rickettsiae were negative. She continued to be febrile. A transthoracic echocardiogram showed dilatation of the mitral valve annulus with bi-leaflet prolapse and vegetation attached to the anterolateral commissure. She was referred to a tertiary care center, and therapy with penicillin, flucloxacillin, and gentamicin was begun for culture-negative endocarditis. Transesophageal echocardiography and visual examination at the time of valve replacement confirmed the presence of large valvular vegetations. After infected tissue was excised, a prosthetic mitral valve was placed. Extended culturing of the blood failed to identify a pathogen. Histopathologic examination of the explanted valve identified fibrinopurulent vegetations with destruction of the valve leaflet. The excised material was split into sections and submitted for culture; all demonstrated a scant growth of Haemophilus parainfluenzae. This finding was identified by a Remel RapID NH Panel (Remel, Lenexa, KS, USA) and confirmed by 16S rRNA gene sequencing. The patient was treated with ampicillin and gentamicin for 2 weeks. She then had 4 further weeks of therapy with daily ceftriaxone at home. She is now well. This patient’s endocarditis was most likely caused by bacteremia from tongue scraping, and the abnormal valve is likely to have been a predisposing factor. The link between oral flora and endocarditis has long been recognized (5), and guidelines for prophylactic use of antimicrobial agents before dental manipulation are established. A literature review did not show any previous reports of endocartitis associated with use of a tongue scraper. There are numerous reports of endocarditis after tongue piercing, with a variety of organisms including viridans streptococci, H. aphrophilus, Neisseria mucosa, and methicillin-resistant Staphylococcus aureus (6–9). Most of these articles reported a pre-existing valvular abnormality, as in our case. Bacteremia caused by routine tooth brushing does not appear to be clinically important, and there are conflicting data about its frequency (10). The inoculum of bacteria transmitted into the bloodstream with brushing may be smaller than that with tooth extraction. Given the frequency of routine tooth brushing, antimicrobial prophylaxis is impractical in any case. The practice of tongue scraping, however, has not been well studied, and both the magnitude and frequency of bacteremia may be greater than with routine tooth brushing. We propose that our patient’s infective endocarditis was most likely a consequence of bacteremia from her use of a tongue scraper. Persons with abnormal cardiac valves and intravascular devices such as pacemakers may be at particular risk. Patients with previous infective endocarditis and high-risk cardiac valve defects should be informed that tongue scraper use is not prudent.

Presence of epidemic Pseudomonas aeruginosa shared between paediatric and adult cystic fibrosis

Background Patients with end stage respiratory disease (ENSD) have an uncertain prognosis, deteriorate rapidly, over a period of days or hours, and commonly die in acute care settings. Introduction The St George end of life pathway was developed in response to evidence that current models of end-of-life care were failing to meet the needs of dying patients. This tool was designed to enable clinicians working in the acute care setting to integrate pivotal palliative care principles in the care of patients. Aim The aim of this observational study was to evaluate the benefits to patients and carers of the endof -life pathway implemented in an acutecare respiratory setting. Method A cohort of dying respiratory patients (n =13), who were placed on the end of life pathway in the period from November 2001 to November 2002, was examined to assess the acceptability and utility of the pathway. This was performed by chart review and staff reflection through a focus group. Results Completed care plans revealed the complexity of symptoms experienced by patients during this vulnerable period of their illness trajectory. Key areas for intervention included management of symptoms such as: pain, respiratory secretions, nausea and vomiting, dyspnoea, personal comfort, psychosocial and spiritual needs. 100% of patients had critical orders and no patients in this cohort received traumatic and unnecessary interventions such as intubation or arterial punctures. Staff described feeling more confident and having more guidance when caring for dying respiratory patients. Conclusion The end of life pathway has proved an important tool for good symptom management and delivery of holistic care. The tool has provided structure and information resources to assist clinicians to care of dying respiratory patients within the acute care setting. This review has confirmed the acceptability and the utility of the end-of-life pathway and underscored the importance of a multidisciplinary approach and a collaborative palliative care model. 01 Respirology (2003) 8, (Suppl.) A1–A65

Rapid genotyping of Pseudomonas aeruginosa using repetitive element based PCr assays

Background Patients with end stage respiratory disease (ENSD) have an uncertain prognosis, deteriorate rapidly, over a period of days or hours, and commonly die in acute care settings. Introduction The St George end of life pathway was developed in response to evidence that current models of end-of-life care were failing to meet the needs of dying patients. This tool was designed to enable clinicians working in the acute care setting to integrate pivotal palliative care principles in the care of patients. Aim The aim of this observational study was to evaluate the benefits to patients and carers of the endof -life pathway implemented in an acutecare respiratory setting. Method A cohort of dying respiratory patients (n =13), who were placed on the end of life pathway in the period from November 2001 to November 2002, was examined to assess the acceptability and utility of the pathway. This was performed by chart review and staff reflection through a focus group. Results Completed care plans revealed the complexity of symptoms experienced by patients during this vulnerable period of their illness trajectory. Key areas for intervention included management of symptoms such as: pain, respiratory secretions, nausea and vomiting, dyspnoea, personal comfort, psychosocial and spiritual needs. 100% of patients had critical orders and no patients in this cohort received traumatic and unnecessary interventions such as intubation or arterial punctures. Staff described feeling more confident and having more guidance when caring for dying respiratory patients. Conclusion The end of life pathway has proved an important tool for good symptom management and delivery of holistic care. The tool has provided structure and information resources to assist clinicians to care of dying respiratory patients within the acute care setting. This review has confirmed the acceptability and the utility of the end-of-life pathway and underscored the importance of a multidisciplinary approach and a collaborative palliative care model. 01 Respirology (2003) 8, (Suppl.) A1–A65