Domiciliary humidification improves lung mucociliary clearance in patients with bronchiectasis

Inspired air humidification has been reported to show some benefit in bronchiectatic patients. We have investigated the possibility that one effect might be to enhance mucociliary clearance. Such enhancement might, if it occurs, help to lessen the risks of recurrent infective episodes. Using a radioaerosol technique, we measured lung mucociliary clearance before and after 7 days of domiciliary humidification. Patients inhaled high flow saturated air at 37 degrees C via a patient-operated humidification nasal inhalation system for 3 h per day. We assessed tracheobronchial mucociliary clearance from the retention of (99m)Tc-labelled polystyrene tracer particles monitored for 6 h, with a follow-up 24-h reading. Ten out of 14 initially recruited patients (age 37-75 years; seven females) completed the study (two withdrew after their initial screening and two prior to the initial clearance test). Seven patients studied were non-smokers; three were ex-smokers (1-9 pack-years). Initial tracer radioaerosol distribution was closely similar between pre- and post-treatment. Following humidification, lung mucociliary clearance significantly improved, the area under the tracheobronchial retention curve decreased from 319 +/- 50 to 271 +/- 46%h (p < 0.07). Warm air humidification treatment improved lung mucociliary clearance in our bronchiectatic patients. Given this finding plus increasing laboratory and clinical interest in humidification mechanisms and effects, we believe further clinical trials of humidification therapy are desirable, coupled with analysis of humidification effects on mucus properties and transport.

Clinical application of a rapid lung-orientated immunoassay in individuals with possible tuberculosis

BACKGROUND

Immunological ex vivo assays to diagnose tuberculosis (TB) have great potential but have largely been blood-based and poorly evaluated in active TB. Lung sampling enables combined microbiological and immunological testing and uses higher frequency antigen-specific responses than in blood.

METHODS

A prospective evaluation was undertaken of a flow cytometric assay measuring the percentage of interferon-gamma synthetic CD4+ lymphocytes following stimulation with purified protein derivative of Mycobacterium tuberculosis (PPD) in bronchoalveolar lavage fluid from 250 sputum smear-negative individuals with possible TB. A positive assay was defined as >1.5%.

RESULTS

Of those who underwent lavage and were diagnosed with active TB, 95% (106/111) had a positive immunoassay (95% CI 89% to 98%). In 139 individuals deemed not to have active TB, 105 (76%) were immunoassay negative (95% CI 68% to 82%). Of the remaining 24% (34 cases) with a positive immunoassay, a substantial proportion had evidence of untreated TB; in two of these active TB was subsequently diagnosed. Assay performance was unaffected by HIV status, disease site or BCG vaccination. In culture-positive pulmonary cases, response to PPD was more sensitive than nucleic acid amplification testing (94% vs 73%). The use of early secretory antigen target-6 (ESAT-6) responses in 71 subjects was no better than PPD, and 19% of those with culture-confirmed TB and a positive PPD immunoassay had no detectable response to ESAT-6.

CONCLUSIONS

These findings suggest that lung-orientated immunological investigation is a potentially powerful tool in diagnosing individuals with sputum smear-negative active TB, regardless of HIV serostatus.

Aetiological role of viral and bacterial infections in acute adult lower respiratory tract infection (LRTI) in primary care

BACKGROUND

Lower respiratory tract infections (LRTI) are a common reason for consulting general practitioners (GPs). In most cases the aetiology is unknown, yet most result in an antibiotic prescription. The aetiology of LRTI was investigated in a prospective controlled study.

METHODS

Eighty adults presenting to GPs with acute LRTI were recruited together with 49 controls over 12 months. Throat swabs, nasal aspirates (patients and controls), and sputum (patients) were obtained and polymerase chain reaction (PCR) and reverse transcriptase polymerase chain reaction (RT-PCR) assays were used to detect Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella pneumophila, influenza viruses (AH1, AH3 and B), parainfluenza viruses 1-3, coronaviruses, respiratory syncytial virus, adenoviruses, rhinoviruses, and enteroviruses. Standard sputum bacteriology was also performed. Outcome was recorded at a follow up visit.

RESULTS

Potential pathogens were identified in 55 patients with LRTI (69%) and seven controls (14%; p<0.0001). The identification rate was 63% (viruses) and 26% (bacteria) for patients and 12% (p<0.0001) and 6% (p = 0.013), respectively, for controls. The most common organisms identified in the patients were rhinoviruses (33%), influenza viruses (24%), and Streptococcus pneumoniae (19%) compared with 2% (p<0.001), 6% (p = 0.013), and 4% (p = 0.034), respectively, in controls. Multiple pathogens were identified in 18 of the 80 LRTI patients (22.5%) and in two of the 49 controls (4%; p = 0.011). Atypical organisms were rarely identified. Cases with bacterial aetiology were clinically indistinguishable from those with viral aetiology.

CONCLUSION

Patients presenting to GPs with acute adult LRTI predominantly have a viral illness which is most commonly caused by rhinoviruses and influenza viruses.

The HRCT appearances of granulomatous pulmonary disease in common variable immune deficiency

Approximately 10% of patients with common variable immune deficiency have systemic granulomatous disease with associated interstitial lung disease. From a population of patients with CVID attending a large tertiary referral clinic for primary immunodeficiency diseases we selected a cohort who had a restrictive defect or impaired gas transfer on pulmonary function testing and/or histologically proven granulomatous disease. HRCT scans of the thorax were reviewed retrospectively in 18 patients by two radiologists. Thirteen patients had diffuse reticulation, which varied from fine to coarse with features of fibrosis. Nodules were found in eight patients. In seven, these were associated with reticulation and in one they were an isolated finding. Bronchiectasis was found as the only abnormality in three and in addition to diffuse reticulation or nodules in another three patients. Greater appreciation of the spectrum of the radiological abnormalities in CVID patients with interstitial lung disease is important. Deteriorating lung function in patients with granulomatous CVID may be secondary to interstitial lung disease rather than bronchiectasis, and treatment should be tailored accordingly.

Mucociliary clearance in COPD can be increased by both a D2/β2 and a standard β2 agonists

In addition to breathlessness and cough, excessive mucus production is one of the main symptoms of chronic obstructive pulmonary disease (COPD). Excess mucus coupled with deteriorating mucociliary clearance is associated with a decline in lung function and an increased risk of death from pulmonary infection. The effect of Viozan (Sibenadet HCl, AR-C68397AA), a novel dual D2 dopamine receptor, beta2-adrenoceptor agonist, on mucociliary clearance was investigated together with that of a beta2-adrenoceptor agonist, salbutamol. Using a double blind, parallel group study design, 15 patients with COPD, all habitual smokers, were randomised to receive nebulised sidenadet (3mg tid; n = 7) or salbutamol (5mg tid; n = 8) for 10 days. Lung mucociliary clearance rates were measured, by a standard radioaerosol technique, before and after the treatment period, as were 24-h sputum volumes. Both sibenadet and salbutamol therapies resulted in significant (P<0.02) enhancement of lung mucociliary clearance. The 24-h sputum volume was significantly reduced following sibenadet therapy (P<0.03) whereas salbutamol therapy had no effect. Our results, in addition to illustrating the effects of a standard beta2 agonist on mucociliary clearance, strongly suggest the potential dual benefit of dual-agonist compounds in lessening sputum production whilst simultaneously enhancing mucociliary clearance. For reasons unconnected with the present study, development work on this specific formulation is no Longer proceeding.

Assessments for oxygen therapy in COPD: are we under correcting arterial oxygen tensions?

There is little data about the use of different oxygen sources during assessment for long-term oxygen therapy (LTOT) and how this impacts upon blood oxygen tensions and prescribed flow rates. Patients with chronic obstructive pulmonary disease (COPD), n=30, had assessments for LTOT using both an oxygen-concentrator and piped hospital oxygen (wall-oxygen) as supply sources. In addition, a random survey of 64 hospitals was conducted to determine what source of oxygen supply was used during assessments. Wall-oxygen was used by 89% of hospitals to perform assessments. During assessments, the median oxygen flow required to achieve an arterial oxygen tension (Pa,O2) >8 kPa was significantly greater for an oxygen-concentrator than for wall-oxygen, with a median difference (range) in flow of 1 (0-3) L. This difference was most likely in those with an forced expiratory volume <30% of predicted. At an oxygen flow of 1 L.min(-1), the mean P(a,O2) using an oxygen-concentrator was significantly lower than that of the wall-oxygen value, with a difference of 1.32+/-1.19 kPa (mean+/-SD). The common practice of using wall-oxygen to perform assessments significantly underestimates the required oxygen-concentrator flow rate. This may have implications for the long-term effect of domiciliary oxygen therapy.

Should doctors wear white coats?

OBJECTIVE

To compare the views of doctors and patients on whether doctors should wear white coats and to determine what shapes their views.

METHODS

A questionnaire study of 400 patients and 86 doctors was performed.

RESULTS

All 86 of the doctors' questionnaires were included in the analysis but only 276 of the patients were able to complete a questionnaire. Significantly more patients (56%) compared with their doctors (24%) felt that doctors should wear white coats (p<0.001). Only age (>70 years) (p<0.001) and those patients whose doctors actually wore white coats (p<0.001) were predictive of whether patients favoured white coats. The most common reason given by patients was for easy identification (54%). Less than 1% of patients believed that white coats spread infection. Only 13% of doctors wore white coats as they were felt to be an infection risk (70%) or uncomfortable (60%). There was no significant difference between doctor subgroups when age, sex, grade, and specialty were analysed.

CONCLUSION

In contrast to doctors, who view white coats as an infection risk, most patients, and especially those older than 70 years, feel that doctors should wear them for easy identification. Further studies are needed to assess whether this affects patients' perceived quality of care and whether patient education will alter this view.

Effect of salmeterol xinafoate on lung mucociliary clearance in patients with asthma

Lung mucociliary clearance is impaired in stable asthma. The long-acting beta2-agonist salmeterol has been shown in vitro to cause a significant increase in ciliary beat frequency. It seemed possible therefore that salmeterol may also have a favourable effect on lung mucociliary transport in asthmatic patients. Fourteen patients with asthma participated in a double-blind, placebo-controlled, crossover study to assess the effect of 2 weeks of treatment with salmeterol MDI (50 microg b.d.) on lung mucociliary clearance. The 11 patients who completed the study (seven males, four females) had a mean +/- SE age of 50 +/- 4 years, % predicted FEV1 of 74 +/- 8% and a tobacco consumption history of 13 +/- 7 pack-years (seven non-smokers, four exsmokers). Lung mucociliary transport was measured by a radioaerosol technique. Pulmonary function indices (FEV1, FVC, and PEF) were significantly improved on salmeterol relative to placebo. The main radioaerosol finding was a significant increase in the penetration of radioaerosol into the lung with 24-h radioaerosol rising from 40 +/- 5% on placebo to 49 +/- 4% (P < 0.01) on salmeterol. Despite this increased penetration, a slight favourable change occurred in tracheobronchial aerosol clearance. This study demonstrates that 2 weeks salmeterol treatment influences deposition of particles within the lung by increasing airway patency and indicates a beneficial effect of MDI salmeterol on lung mucociliary clearance.

Comparison of the views of junior doctors, consultants and managers on work and training

OBJECTIVE

To determine the views of junior hospital doctors on their working conditions, NHS reforms and training, and to compare their views with those of consultants and managers.

SUBJECTS

A questionnaire was distributed to 52 junior doctors, 19 consultants and 14 middle or senior grade managers in an acute NHS trust.

CONCLUSIONS

Junior doctors had strong feelings about several areas covered in the questionnaire; in particular, more structured training without the requirement to undertake a higher degree would be welcomed. Shift systems are unpopular and the reduction of 'non-medical' tasks with a reduction in work intensity is perceived to be more important than further reductions in hours available for work.

Comparison of polymerase chain reaction for IS6110 and Amplicor in the diagnosis of tuberculosis

BACKGROUND

Polymerase chain reaction (PCR) amplification of Mycobacterium tuberculosis DNA offers the potential of a sensitive and specific diagnostic test for tuberculosis. To evaluate this technique from the clinician's perspective, samples were collected from patients with chronic respiratory disease and the sensitivity and specificity of a newly introduced commercially available PCR kit (Amplicor) was compared with that of an established method to detect the target sequence IS6110.

METHODS

Sputum or bronchial washings from patients with active tuberculosis, previously treated tuberculosis or other selected respiratory illnesses were analysed by both techniques and their sensitivity and specificity determined.

RESULTS

Amplicor was more specific than IS6110 in the diagnosis of active infection (98% versus 79%). Both techniques were equally sensitive (92%).

CONCLUSION

These results suggest that analysis of respiratory samples by Amplicor PCR in inner city populations of patients has greater specificity for a diagnosis of active tuberculosis than PCR for IS6110, and thus Amplicor PCR may aid the clinician in making a diagnosis of active tuberculosis.

Visual laser ablation of the prostate: a preliminary report

OBJECTIVE

To report our preliminary experience with visual laser ablation of the prostate (VLAP) for treating bladder outlet obstruction caused by benign prostatic hyperplasia (BPH) and to evaluate its short-term outcome.

DESIGN

We reviewed our laser technique in 47 men with symptomatic obstruction caused by BPH who underwent VLAP between July 1992 and April 1993 at our institution, and we compared our results with those reported in the literature.

MATERIAL AND METHODS

Our 47 patients were from 43 to 87 years old (mean, 69.6). The mean pretreatment American Urological Association symptom score was 22, mean peak flow rate was 9.5 mL/s, and mean postvoid residual urinary volume was 136 mL. Neodymium:yttrium-aluminum-garnet laser energy was delivered at the 2-, 4-, 8-, and 10-o'clock positions and, when necessary, to the median lobe by one of two lateral-firing laser probes. All but the first four patients were treated on an outpatient basis, and all patients were catheterized (Foley catheter) for 2 to 10 days after VLAP.

RESULTS

Of the 47 patients, 32 had data pertaining to a mean follow-up of 5 months; they had a mean symptom score of 10, mean peak flow rate of 15.7 mL/s, and mean postvoid residual volume of 63 mL. In 12 patients, data from a mean follow-up of 11 months were available; they had a mean symptom score of 6, mean peak flow rate of 18.8 mL/s, and mean postvoid residual volume of 10 mL. Perioperative complications (myocardial infarction, thrombophlebitis, and epididymitis) in three patients responded to conservative therapy. Urinary retention occurred for 2 to 60 days after initial removal of the Foley catheter in 12 patients, who then had resumption of spontaneous voiding. In three patients who stated their condition was worse postoperatively, conventional transurethral resection of the prostate was done 6 months after VLAP, and a fourth patient had a persistently obstructive bladder neck incised 8 months after VLAP.

CONCLUSION

Our early experience and that reported in the literature indicate that VLAP is a safe and efficacious alternative treatment of obstructive BPH. Although the early results of VLAP rival those of transurethral resection of the prostate, the success rate in treating large prostates should be improved, and long-term results should be assessed to determine the durability of the beneficial effects.

The effect of nebulized salbutamol therapy on the incidence of postoperative chest infection in high risk patients

Patients who smoke heavily and those with pre-existing airflow obstruction are at particular risk of postoperative respiratory infection following upper abdominal surgery. This invariably prolongs hospital stay and increases morbidity. In order to determine whether high dose bronchodilator therapy in the perioperative period reduced the risk of infection, all patients undergoing elective upper abdominal surgery were assessed for risk of developing postoperative infection. Fifty-three patients were identified as high risk according to previously published criteria and were randomly allocated to receive nebulized salbutamol (5 mg) or saline placebo 6 hourly for 48 h beginning 1 h preoperatively. There was no difference in rates of postoperative chest infection in the two groups and this study, therefore, provides no support for the routine preoperative use of bronchodilators in these patients.

Compliance with use of the Hydrate 1 system by patients with treated urolithiasis

Adequate hydration, leading to decreased urine osmolality and increased solubility of urinary constituents, is the cornerstone of urolithiasis prevention. Hydrate 1 is a system designed to allow patients to monitor urine osmolality by a simple colorimetric method, thereby adjusting their fluid intake. In 10 patients treated surgically for stone disease, the device worked well when used, guiding patients to increase intake appropriately. However, compliance was sporadic, determined principally by occupational or lifestyle constraints. Use of this system may have a place in that subset of patients with recurrent stone disease who have difficulty maintaining adequate urine volume.

Effect of nifedipine on kidney and ureteral function after experimental acute unilateral ureteral obstruction

Nifedipine, a calcium channel blocker, was tested for its in vivo effect on the ureter and kidney during acute obstruction. There was no discernible effect on peristalsis but glomerular filtration rate was improved. Thus, nifedipine would not be expected to decrease renal colic from obstruction.

Microbial flora of the trachea during intubation of patients undergoing upper abdominal surgery

BACKGROUND

The presence of Haemophilus influenzae in the oropharynx is correlated with the subsequent development of chest infection. The importance of colonisation of the trachea by bacteria at the time of surgery is uncertain. This study investigated the tracheal flora at the time of intubation in 24 patients undergoing elective upper abdominal surgery.

METHODS

The bacterial flora of the trachea was sampled in all 24 patients immediately after intubation and immediately before extubation. Patients were assessed postoperatively for the development of chest infection.

RESULTS

Bacteria, including H influenzae in five cases, were isolated from the post-intubation brushings of the trachea of 15 patients. The pre-extubation brushings from only four patients yielded growth. Three of five patients developing a chest infection were colonised by H influenzae according to the postintubation brush, compared with two of 19 without chest infections. Before extubation two of five developing chest infections had H influenzae in the trachea but none of 19 without infection. All but one of the patients from whom H influenzae was isolated were smokers.

CONCLUSIONS

These results suggest that the increased risk of postoperative chest infection in cigarette smokers may be due in part to colonisation of the trachea by H influenzae at the time of operation.

Postoperative chest infection after upper abdominal surgery: an important problem for smokers

The incidence and risk factors for postoperative chest infection have been studied in 127 patients undergoing elective upper abdominal surgery. The overall incidence of postoperative chest infection was 20.5%. Mean length of postoperative stay was extended from 7.8 to 10.7 days in those developing infection (P less than 0.05). Patients who smoked cigarettes and those with smoking related diseases had a considerably higher risk of infection. Patients with chronic bronchitis and airflow obstruction had an incidence of infection of 85.7%, those with chronic bronchitis alone 83.3% and those with airflow obstruction and no chronic bronchitis 50%. Patients with a smoking history of greater than or equal to 20 pack years but no chronic bronchitis or airflow obstruction had an incidence of 20.8%. All three were independently significant risk factors for infection. Patients without respiratory disease and who were non-smokers had an incidence of infection of only 7.1%. Smoking and its sequelae are the principal risk factors for postoperative chest infection. This study shows that the high risk patient can readily be identified by enquiry into respiratory symptoms, smoking history and by spirometry. This is the group in whom prophylactic measures are especially important, and they require close supervision to enable early identification and therapy of infection.

Non-germ cell tumors of testis

Testicular tumors of non-germ cell origin represent from 5 percent to 10 percent of all testicular neoplasms. Included in this group are sex cord/gonadal stromal tumors, most originating from Leydig or Sertoli cells, mixed tumors, and tumors of mesenchymal or hematopoietic origin. In addition, various miscellaneous lesions, tumor-like conditions, and secondary testicular tumors may be classified as non-germ cell tumors. This review covers the presentation, diagnosis, and treatment of these rare lesions.

Oropharyngeal flora and chest infection after upper abdominal surgery

The oropharyngeal flora was determined before and after operation in 127 patients undergoing upper abdominal surgery. Swabs of the oropharynx were obtained on the day before operation and on the first, third, and fifth postoperative days. Isolation of Haemophilus influenzae, Streptococcus pneumoniae, and coliforms was noted. In the 108 patients with the full series of throat swabs the incidence of oropharyngeal colonisation by H influenzae was 16% and was unchanged after operation. S pneumoniae was present in only 5.6 (six patients) before operation and the incidence fell to 1.9% (two patients). There was a transient rise in coliform colonisation postoperatively. Twenty four patients developed a chest infection. In eight a bacterial cause was established, in six H influenzae and in two S pneumoniae. There was a significant relation between the carriage of H influenzae before operation and development of a chest infection. H influenzae was also found more often in cigarette smokers. The presence of S pneumoniae or coliform organisms before surgery was not related to the development of infection. The high incidence of postoperative chest infection in cigarette smokers appears to be due in part to preoperative colonisation of the oropharynx by H influenzae.

Cough following general anaesthesia and abdominal surgery

Postoperative chest infection is a common complication of general surgery. We have assessed some of the risk factors implicated and reviewed the role of the cough reflex in the immediate postoperative period.

Acceptability of oxygen concentrators: the patient's view

The impact of the installation of an oxygen concentrator on the lifestyle of 30 patients in two health districts has been investigated using a questionnaire. Marked improvements in general well-being (83% of respondents), breathing (82%), mobility (62%) and sleep pattern (52%) were reported. The long term nature of the aims of treatment were understood by 83% of the respondents and the mean period of time the patients used the concentrator was satisfactory. However, 34% of respondents had a concentrator with only one outlet and 70% had the concentrator situated in a commonly used room with the possibility of problems with noise. Thirty one percent of the respondents were still smoking. The recommendations given to patients for the sitting of the concentrator and the number of outlets should be improved. However, the oxygen concentrator was found to be generally well tolerated and this refutes criticism that patients may find it restricting.

Cough threshold after upper abdominal surgery

The effect of upper abdominal surgery under general anaesthesia on the cough threshold was studied in 26 patients, on the basis of the concentrations of capsaicin and citric acid causing cough. Cough threshold was determined after administering doubling doses of nebulised aerosols of capsaicin and citric acid before operation and on the first and fourth postoperative days. There was an increase in cough threshold (decrease in cough sensitivity) in response to both inhaled irritants on the first postoperative day from the preoperative day and a return towards preoperative values by the fourth day after surgery. The increase in cough threshold on the first postoperative day correlated with the time since opiate administration (r = 0.7 for capsaicin, 0.52 for citric acid). These results show that the threshold concentration of chemical irritants causing cough is increased on the first postoperative day after upper abdominal surgery.

Experimental prostatitis in nonhuman primates: I. Bacterial adherence in the urethra

Both man and monkey possess urothelial (transitional cell) receptors for P-fimbriae of Escherichia coli; however, the male urethra has pseudostratified columnar cells. We studied adherence using scanning electron microscopy and found that P-fimbriae were the principal mediators of adherence to these cells as well. The monkey, therefore, should be a good model for the study of the ascending route of infection in prostatitis, the route thought to occur in man.

Experimental prostatitis in nonhuman primates: II. Ascending acute prostatitis

Bacterial prostatitis is a common cause of urinary tract infection in males, but little is known of its pathophysiology. To study this, we developed a nonhuman primate model using a wild-type clinical isolate of Escherichia coli. Primates have a prostatic anatomy that is similar to humans, which makes them ideal as an animal model of this disease. The monkeys had a urethral inoculation of this organism and were then followed with urine, blood, and semen cultures, white blood counts, and renal scans. They were sacrificed at from 10 days to 4 weeks, and their genitourinary tracts histologically examined. The prostatitis paralleled that reported in humans, and we conclude that the infection occurs by the ascending route. The organisms causing the infection in man do so in our primate model, and the histologic change is also the same. Thus, the primate model holds promise for studies to help us understand this disease.

Prescription of oxygen concentrators: adherence to published guidelines

The indications for the prescription of oxygen concentrators have been assessed in 82 patients against the Department of Health guidelines, except that only one set of blood gas and spirometry measurements was required if the patient's condition was stable. Of the 49 patients recommended for this treatment by a chest physician, 41 (82%) fulfilled the requirements, compared with only 11 of 33 patients where the concentrator was recommended by a general practitioner or non-specialist physician. Eleven patients died within one month of prescription. The results show that many patients are being prescribed oxygen concentrators without assessment and underline the importance of full assessment and attention to prognosis before prescription.