An evaluation of methods for the isolation of nontuberculous mycobacteria from patients with cystic fibrosis, bronchiectasis and patients assessed for lung transplantation.

BACKGROUND: RGM medium is an agar-based, selective culture medium designed for the isolation of nontuberculous mycobacteria (NTM) from the sputum of patients with cystic fibrosis (CF). We evaluated RGM medium for the detection of NTM in patients with CF (405 samples), bronchiectasis (323 samples) and other lung diseases necessitating lung transplantation (274 samples). METHODS: In total, 1002 respiratory samples from 676 patients were included in the study. Direct culture on RGM medium, with incubation at two temperatures (30 °C and 37 °C), was compared with conventional culture of decontaminated samples for acid-fast bacilli (AFB) using both a solid medium (Löwenstein-Jensen medium) and a liquid medium (the Mycobacterial Growth Indicator Tube; MGIT). RESULTS: For all three patient groups, significantly more isolates of NTM were recovered using RGM medium incubated at 30 °C than by any other method (sensitivity: 94.6% vs. 22.4% for conventional AFB culture; P < 0.0001). Significantly more isolates of Mycobacterium abscessus complex were isolated on RGM at 30 °C than by AFB culture (sensitivity: 96.1% vs. 58.8%; P < 0.0001). The recovery of Mycobacterium avium complex was also greater using RGM medium at 30 °C compared to AFB culture (sensitivity: 83% vs. 70.2%), although this difference was not statistically significant and a combination of methods was necessary for optimal recovery (P = 0.21). CONCLUSIONS: In the largest study of RGM medium to date, we reaffirm its utility for isolation of NTM from patients with CF. Furthermore; we show that it also provides an effective tool for culture of respiratory samples from patients with bronchiectasis and other lung diseases.

Volatile biomarkers of Pseudomonas aeruginosa in cystic fibrosis and noncystic fibrosis bronchiectasis.

AIMS: The purpose of this study was to determine whether volatile organic compounds specific to Pseudomonas aeruginosa could be detected in clinical sputum specimens. METHODS AND RESULTS: Patients were recruited from specialist bronchiectasis and cystic fibrosis clinics. The gold standard for diagnosing Ps. aeruginosa infection was a positive sputum culture. About 72 sputum headspace samples taken from patients at risk of or known to have prior Ps. aeruginosa infection were analysed by solid phase micro-extraction mass spectrometry. 2-nonanone was a marker in Ps. aeruginosa in sputum headspace gas with sensitivity of 72% and specificity of 88%. A combination of volatile compounds, a sputum library of 17 compounds with 2-nonanone, increased sensitivity in the detection of Ps. aeruginosa to 91% with specificity of 88%. CONCLUSIONS: In contrast to the 48-hour turnaround for classical microbiological culture, these results were available within 1-2 h. These data demonstrate the potential for rapid and accurate diagnosis of Ps. aeruginosa infection from sputum samples. SIGNIFICANCE AND IMPACT OF THE STUDY: 2-Nonanone is a compound requiring further study in the exhaled breath as it may improve diagnostic of Ps. aeruginosa infection when combined with other reported volatile markers.

Assessment of sample handling practices on microbial activity in sputum samples from patients with cystic fibrosis.

AIM: The aim of this study was to quantitatively and qualitatively assess the effect of sample storage on the metabolically active microbial community found in sputum samples from patients with cystic fibrosis (CF). METHODS: Sputum samples were collected and split in two equal aliquots one of which was immersed in RNAlater and refrigerated immediately, the second stored at room temperature for 24 h and RNAlater was subsequently added. mRNA was extracted, and RT-PCR-DGGE and qPCR analysis of the bacterial and fungal communities was carried out. RESULTS: Significant differences in the bacterial communities between the two protocols were observed but there were no significant difference seen in the fungal community analyses. Analysis by qPCR demonstrated that room temperature storage gave statistically significant increases in eubacteria and Pseudomonas spp. and a statistically significant decrease in those of Haemophilus influenzae. CONCLUSIONS: The analysis of metabolically active microbial communities from CF sputum using molecular techniques indicated that samples should be stored at 4 degrees C upon addition of RNAlater to obtain an accurate depiction of the CF lung microbiota. Also, storing respiratory samples at room temperature may cause an over representation of Pseudomonas aeruginosa and mask the presence of other clinically significant organisms.

An integrated model of provision of palliative care to patients with cystic fibrosis.

Palliative care of patients with cystic fibrosis (CF) is often undertaken by CF teams rather than palliative care teams because of the specialist nature of the disease and the potential role of lung transplantation. We developed an integrated model of provision of palliative care whereby most care is delivered by the CF team using palliative guidelines and pathways, with additional support available from the specialist palliative care team when needed. We report our experience of the terminal care of 40 patients with CF with regard to the circumstances of death, lung transplantation status, specific symptoms and provision of palliative treatments. The transition from disease modifying treatments to palliative care was particularly complex. Patients had a high level of symptoms requiring palliation and most died in hospital. Palliative care is a crucial component of a CF service and requires the specialist skills of both the CF and palliative care teams.

Aquagenic palmar wrinkling as a presenting feature of cystic fibrosis gene dysfunction.

Aquagenic palmar wrinkling (APW) is characterized by the rapid and transient oedematous wrinkling of the palms after brief immersion in water. APW has been associated with cystic fibrosis (CF). Since the discovery of the CF gene, the clinical spectrum of CF has broadened from classic severe CF to include milder 'atypical CF' and 'CF-related disorders'. We report an unusual case in which APW occurred in a patient with no lung disease, and in whom investigations showed evidence of CF gene dysfunction. APW may be a presenting feature of a CF-related disorder and should prompt investigation of CF gene dysfunction.

Interstitial lung disease: progress and problems.

Interstitial lung disease involves all areas of medicine as it often occurs in patients with comorbidities or as a consequence of systemic diseases and their treatment. Typically the physician is faced with a breathless patient, a diffusely abnormal chest radiograph, and a wide differential diagnosis. Progress has been made in using high resolution computed tomography as the key investigation in characterising the pattern and extent of the disease. Bronchoalveolar lavage is particularly important in excluding infection as a cause of diffuse lung infiltrates. Surgical lung biopsies have led to a new classification system for the range of histopathological patterns of disease that were previously known by the collective term cryptogenic fibrosing alveolitis. Problems persist in deciding when a surgical lung biopsy is clinically justified, in understanding the pathogenesis of these diseases, and in finding more effective treatments.

Epidemiology and molecular typing of an outbreak of tuberculosis in a hostel for homeless men.

AIM: To investigate a possible outbreak of tuberculosis in a hostel for homeless men using IS6110 profiling, a polymerase chain reaction (PCR) based fingerprinting technique. METHODS: Eight cases of tuberculosis were diagnosed in residents of the hostel over a period of 28 months. To provide epidemiological data, a heminested inverse PCR (HIP) assay targeting the insertion sequence IS6110 together with its upstream flanking region was used to fingerprint the eight isolates of M tuberculosis under investigation. RESULTS: The HIP technique gave IS6110 profiles which showed that while three isolates were clearly distinct, the remaining five strains were indistinguishable, suggesting the latter were representatives of a single outbreak strain. CONCLUSIONS: The HIP assay proved discriminatory and facilitated repeated testing for the direct comparison of strains as more patients presented over the protracted course of this outbreak.

Cyclophosphamide in severe steroid-resistant bronchiolitis obliterans organizing pneumonia.

A patient receiving carbamazepine and imipramine presented with severe bronchiolitis obliterans organizing pneumonia (BOOP). He developed progressive respiratory failure in spite of high-dose steroid treatment. Cyclophosphamide was given as adjunctive therapy, and a rapid improvement was seen. The authors suggest that an early therapeutic trial of cyclophosphamide should be considered in patients with BOOP who fail to respond to steroids.

Communicating the diagnosis of lung cancer.

In order to assess their reaction to the information given, 50 patients underwent a semi-structured interview with a social worker within 1 week of having been told the diagnosis of lung cancer. There were 32 men and 18 women with a mean age of 63 (range 38-82) years. Thirty-eight (76%) belonged to Registrar General social class IV or V, and 45 (90%) had left school at the age of 15 years. Two patients were unaware of the diagnosis despite having been told that they had lung cancer. Two patients would have preferred not to have been told the diagnosis and two were unsure, while 46 (92%) felt that telling them the diagnosis truthfully had been correct. No patient felt that they had been given too much information, but 13 (26%) indicated a lack of information about prognosis. Despite being told 'bad news', 31 (62%) felt more reassured after their interview with the doctor, 5 (10%) felt less reassured, and 14 (28%) were uncertain. Twenty-one (42%) patients were experiencing a sense of guilt or regret at having smoked. Many patients had concerns about specific symptoms which they expected to suffer. In general, patients wanted to be told their diagnosis truthfully and required a high level of information. Many patients felt reassured by the discussion of such details.

Lyme disease.

Neurological problems form an important part of the clinical spectrum of Lyme disease. A triad of aseptic meningoencephalitis, cranial neuritis and peripheral neuritis is unique to the disease. However, the list of neurological manifestations described includes pseudotumour cerebri, hemiparesis, demyelinating disorders, optic atrophy, recurrent laryngeal nerve palsy and purulent meningitis so that Lyme disease must now be considered in the differential diagnosis of a wide range of neurological disorders.

The management and outcome of late post-infarct ventricular tachycardia presenting to a district general hospital.

A review was undertaken of late post-infarct ventricular tachycardia in a district hospital cardiac care unit in order to study the clinical course of a total population of such patients from initial presentation to ultimate outcome. Thirty-six patients with this diagnosis were identified over a 3 1/2-yr period. Twelve were treated by empirically chosen antiarrhythmic drugs. Twenty-four were referred for electrophysiologically guided treatment, of whom 16 were treated by antiarrhythmic drugs, 3 by anti-ischaemic measures alone, and 5 by non-pharmacological antiarrhythmic treatments (antiarrhythmic surgery, percutaneous ablation, defibrillator implantation, cardiac transplantation). Of those treated empirically, 4 died in hospital of their arrhythmia, 1 died suddenly at home, and 2 suffered non-fatal arrhythmia recurrences during mean follow-up of 20 months. There were no arrhythmic deaths in those whose treatment was guided by serial electrophysiology studies, although 4 patients died of cardiac failure or reinfarction, and 3 were hospitalised with a recurrence of ventricular tachycardia during mean follow-up of 16 months. Age, concomitant medical problems and the apparent response to initial antiarrhythmic therapy were the main factors influencing management decisions. The apparent superiority of more intensive management strategies based on electrophysiology studies must be interpreted in the context of the selection processes applied to the total population initially presenting.

A comparison of the seroepidemiology of chlamydial infection in pigeon fanciers and farmers in the U.K.

A detailed comparative seroepidemiological study of antibody responses was performed in 271 pigeon fanciers and 100 farmers. Overall 73% of pigeon fanciers had IgG antibodies at a titre greater than or equal to 16 to Chlamydia pneumoniae, 39% to Chlamydia psittaci, and 6.6% to Chlamydia trachomatis. The prevalence of chlamydial antibodies was significantly lower in the farmers at 47% for C. pneumoniae, 6% for C. psittaci, and 2% for C. trachomatis. Both populations were exposed to complex microbiological and antigenic environments: 50.5% of the pigeon fanciers had antibodies to pigeon antigens, 34% to egg membrane, and 0.73% to yolk sac antigen, and 59% of the farmers had antibodies to Micropolyspora faeni, but the high prevalence of chlamydial antibodies could not be attributed to interaction with these antigens. There was considerable overlap of chlamydial antibody responses in the pigeon fanciers but not in the farmers: 36% of the pigeon fanciers had antibodies to C. pneumoniae alone, 5% to C. psittaci alone, and 31% to both agents, whereas only 3% of farmers had antibodies to both C. pneumoniae and C. psittaci. The high prevalence of antibodies to C. psittaci in the pigeon fanciers is compatible with the known avian reservoir for this infection. The particularly high prevalence of antibodies to C. pneumoniae suggests that complex interactions may be occurring in a population exposed to two chlamydial organisms, whereby infection with one species may provoke an anamnestic response against other chlamydial organisms with which the subject has previously been infected.

Serological cross-reactivity among chlamydial strains in a family outbreak of psittacosis.

Three members of a family of nine persons contracted psittacosis with severe pneumonia, respiratory failure, delirium, hepatitis and renal involvement. A newly purchased cockatiel was probably the primary source of infection but person-to-person transmission is likely to have taken place between twin brothers who shared a bedroom, one of whom had no direct contact with birds. Type-specific chlamydial serological tests identified the infecting agent as Chlamydia psittaci. The highest titres in the initial samples of serum from the patients, however, were to C. psittaci TWAR (Taiwan Acute Respiratory) and serological cross-reactivity among chlamydial strains was demonstrated. This study of a clearly defined outbreak of psittacosis provides useful information for those undertaking larger population surveys of chlamydial disease and emphasises the need for detailed serological investigation of cases.

Ventilation perfusion radionuclide imaging in cryptogenic fibrosing alveolitis.

There is increasing interest in ventilation perfusion (V/Q) imaging in cryptogenic fibrosing alveolitis because of the data these scans provide on the dynamic V/Q relationships in such patients undergoing single lung transplantation. However, the full spectrum of V/Q abnormalities in this disease is poorly defined. We therefore analysed the V/Q scans of 45 consecutive patients with advanced cryptogenic fibrosing alveolitis being considered for single lung transplantation. Scans were classified according to the presence, severity and degree of matching of defects in ventilation and perfusion images and the results were compared with the data obtained from lung function tests. Ventilation images showed defects in 13 (29%) and 'washout delay' in 15 (33%) patients; 10 (22%) patients had asymmetric distribution of ventilation with one lung receiving > 60% of total ventilation. Perfusion images showed normal perfusion in 8 (18%), mild defects in 18 (40%) and major defects in 19 (42%) patients. The distribution of perfusion between lungs was significantly asymmetric in 20 (45%) patients. V/Q images were matched in 15 (33%), mildly mismatched in 15 (33%) and severely mismatched in 15 (33%) patients, but the degree of V/Q mismatch did not show a relationship to KCO, PaO2 or A-aO2 gradient. The appearances were atypical of pulmonary embolism in eight patients. V/Q images in cryptogenic fibrosing alveolitis show a diverse range of appearances and may mimic pulmonary embolism. V/Q imaging complements the data obtained from lung function tests and is particularly useful in defining the differential function of each lung which is particularly important in the assessment of patients for single lung transplantation.