HIV seroprevalence by anonymous testing in patients with Mycobacterium tuberculosis and in tuberculosis contacts.

Having witnessed a large increase in Mycobacterium tuberculosis notifications in south London, we wanted to ascertain the prevalence of HIV and tuberculosis co-infection in our patients. All patients with tuberculosis and their contacts were anonymously tested for HIV in blood and saliva, respectively. 11.4% of patients (from various demographic groups) with tuberculosis who attend chest clinics in south London are HIV positive. In addition, 5% of individuals seen in the tuberculosis contact screening clinics and 4% new entrants are HIV positive. All patients with Mycobacterium tuberculosis, irrespective of background, should be urged to have an HIV test.

Effect of salmeterol on Pseudomonas aeruginosa infection of respiratory mucosa.

We have studied the effect of salmeterol on both P. aeruginosa interactions with the mucosa of nasal turbinate organ cultures and on pyocyanin-induced (20 microg/ml) and elastase-induced (100 microg/ml) damage to nasal epithelial cells. Organ cultures were exposed to salmeterol either by preincubation with 4 x 10(-7) M salmeterol for 30 min or by pipetting 20 microl of 4 x 10(-7) M salmeterol onto the organ culture surface immediately prior to bacterial inoculation. Infected organ cultures (8 h) had significantly (p < or = 0.01) increased epithelial damage, and P. aeruginosa was predominantly associated with damaged epithelium and mucus. Salmeterol significantly (p < or = 0.02) reduced epithelial damage caused by infection and the total number of adherent bacteria (p < or = 0.05), but bacterial distribution on the mucosa was unchanged. Nasal epithelial cells incubated with pyocyanin (20 microg/ml) or elastase (100 microg/ml) for 3 h had significantly (p < or = 0.05) increased cytoplasmic blebbing and mitochondrial damage versus control values. Elastase also significantly (p < or = 0.05) increased cell projection and reduced the level of ciliation. Cells preincubated with salmeterol (2 x 10(-7) M) showed a significant reduction in some features of cell damage caused by both toxins, which was inhibited by the beta2-adrenoceptor antagonist propranolol. Our results indicate that salmeterol reduces P. aeruginosa-induced damage to both organ culture and nasal epithelium.

Ciliary disorientation alone as a cause of primary ciliary dyskinesia syndrome.

Ciliary disorientation has been proposed as a variant of primary ciliary dyskinesia (PCD); cilia have normal ultrastructure and normal or near normal ciliary beat frequency (CBF) but lack efficacy because their beat direction is disorientated. We have identified 11 patients, including two siblings, with the clinical features of PCD, who satisfy these criteria. A chest radiograph, pulmonary function tests, nasal mucociliary clearance (NMCC), CBF, ciliary ultrastructure, and orientation were assessed in each subject. One patient had biopsies taken from the nose and both main bronchi. Eight patients had a computed tomography scan (CT) of the thorax; the clinical features were compatible with PCD. Cilia ultrastructure was normal and NMCC was absent in all cases. Mean CBF was normal (11.6-14.9 Hz) in five cases and slow in six (range 8.4-9.7 Hz). Ciliary beat pattern was stiff in seven cases, six of which had slow CBF. The cilia were disorientated when measured by both the central pair (range, 21.8 degrees - 26.4 degrees) and basal feet (range, 20.6 degrees - 28.9 degrees) compared with 16 normal controls (range, 11.0 degrees - 15.5 degrees and 12.3 degrees - 17.6 degrees, respectively). Two siblings had the clinical features of PCD and ciliary disorientation alone on repeated biopsies taken 10 yr apart. Orientation of cilia from the nose and bronchus was similar. Two cases had unchanged ciliary disorientation after 3 mo of treatment with antibiotics and topical corticosteroids. We concluded that ciliary disorientation alone can lead to the clinical syndrome of PCD.

A human respiratory-tissue organ culture incorporating an air interface.

The immersion of respiratory tissue in organ cultures is unphysiologic and may influence the interactions of the tissue with experimental agents. We have assessed an organ culture of human nasal turbinate tissue with an air interface by light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), with and without replacement of culture medium. Without replacement of medium, ciliary beat frequency (CBF) was normal (11.3 +/- 0.5 Hz) at 5 d, but fell significantly (p<0.05) to 7.9 +/- 0.8 Hz at 10 d. The degree of ciliation decreased significantly (p<0.05) at 4 and 10 d. Nuclear heterochromatin in all cell types was significantly (p<0.05) reduced at 5 d. Significant (p<0.05) mitochondrial abnormalities occurred in ciliated cells at 5 d and in both ciliated and unciliated cells at 10 d. With daily replacement of medium, CBF fell significantly (p<0.05) from 11.6 +/- 0.2 Hz at Time 0 to 10.6 +/- 0.3 Hz after 20 d. The proportions of ciliated and nonciliated cells did not change after 20 d, but the proportion of mucus cells was higher at 20 d (26.3 +/- 5.4%) than at Time 0 (9.8 +/- 2.7%). No mitochondrial abnormalities, changes in nuclear heterochromatin levels, or reduction in cilial density on ciliated cells were present. The amount of damaged epithelium was less at 20d (7.2 +/- 3.8%) than at Time 0 (19.0 +/- 5.8%). This model more closely reproduces physiologic conditions in vitro than do models involving the immersion of respiratory tissue in media. Its long viability will permit studies of virus and bacterial infections, and of the effects of pharmacologic agents and environmental factors.

Bronchitis.

Acute bronchitis in previously fit individuals is a common condition that is usually mild and self limiting. Chronic bronchitis remains a common cause of morbidity and mortality, and the cost to the nation due to lost working days and to health services is enormous. Cigarette smoking is the major etiologic factor, although exacerbations may be caused by viruses, environmental pollutants, allergic responses, and bacterial infections. New insights into the underlying basic mechanisms of bronchial inflammation are being made. Antibiotics are commonly used to treat exacerbations, although evidence of efficacy is sometimes lacking. Some patients may be prone to recurrent exacerbations and this influences their chance of recovery. Clinical trials must include an assessment of the severity of the exacerbation, and protocols would be improved by increased definition of the type of patient being enrolled and by inclusion of more detailed measures of benefit. Influenza and pneumococcal vaccination should be encouraged in appropriate patients.

Ciliary disorientation in patients with chronic upper respiratory tract inflammation.

Random ciliary orientation was recently described as a possible variant of primary ciliary dyskinesia (PCD). The cilia have normal ultrastructure and nearly normal ciliary beat frequency (CBF) but lack efficacy because the beat direction is disoriented. However, delayed mucociliary clearance (MCC), transitory changes in ultrastructure, and slowed CBF can all occur in the presence of inflammation. This study investigated groups of patients with upper respiratory tract inflammation caused by infection to assess whether ciliary disorientation was present and its relation to MCC. The study population consisted of 10 healthy nonatopic nonsmoking volunteers, 15 patients with idiopathic bronchiectasis and chronic mucopurulent sinusitis, 12 patients with cystic fibrosis, and two patients with the clinical features of PCD but normal CBF and ciliary ulstrastructure. Ciliary disorientation was significantly (p < 0.05) increased in the three patient groups compared with the volunteers, being greatest in the two patients with the clinical features of PCD and in bronchiectasis patients with P. aeruginosa, and was positively correlated (r = 0.9) with MCC but not with CBF. Treatment of one patient with antibiotics and topical corticosteroids for a prolonged period resulted in ciliary disorientation returning to normal. Ciliary disorientation may therefore occur secondary to inflammation caused by infection, and the study suggests that ciliary disorientation rather than ultrastructural abnormalities or slow CBF results in delayed MCC.

Interaction of pneumolysin-sufficient and -deficient isogenic variants of Streptococcus pneumoniae with human respiratory mucosa.

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia, and pneumolysin, a hemolytic toxin, is thought to be an important virulence factor. We have studied the interaction of a pneumolysin-sufficient type II S. pneumoniae strain (PL+) and an otherwise identical pneumolysin-deficient derivative (PL-) with human respiratory mucosa in an organ culture with an air interface for up to 48 h. Ciliary beat frequency (CBF) was measured by a photometric technique, and adherence to and invasion of the epithelium were assessed by scanning and transmission electron microscopy. PL+ and PL- caused a progressive fall in CBF compared with the control which became significant (P < 0.01) at 24 h for PL+ and at 48 h for PL-. At 24 h, there was a significant increase in the percentage of the mucosa of the organ culture that was damaged for PL+ compared with the control (P < 0.01) and PL- (P < 0.02). At 48 h, there was a significant increase in mucosal damage for both PL+ (P < 0.005) and PL- (P < 0.05) compared with the control. At 24 and 48 h, PL+ and PL- adhered predominantly to mucus and damaged cells. PL+ infection alone caused separation of tight junctions between epithelial cells, and at 48 h PL+ cells were adherent to the separated edges of otherwise healthy unciliated cells. PL+ and PL- both caused damage to the epithelial cell ultrastructure. S. pneumoniae infection caused patchy damage to the respiratory mucosa and a lowered CBF. These changes were more severe and occurred earlier with the pneumolysin-sufficient variant.

The effect of variations in the expression of pili on the interaction of Neisseria meningitidis with human nasopharyngeal epithelium.

Bacterial adherence is essential to colonization of the nasopharynx by Neisseria meningitidis, and pili may facilitate adherence. Scanning electron microscopy and immunogold labeling were used to study the interaction of 2 piliated and 1 nonpiliated variant of N. meningitidis with nasopharyngeal mucosa in an adenoid organ culture system with an air-mucosal interface. Meningococcal infection caused epithelial damage, loss of ciliated epithelium, and ciliary disorganization, which progressed with time and were greater with the piliated strains. Pili increased adherence of meningococci to the mucosa, and there was tropism of piliated strains for nonciliated cells containing microvilli, damaged epithelium, and sites of cell separation. Bacterial adherence was associated with a change in the appearance of the microvilli.

Efficacy and safety of long-term ciprofloxacin in the management of severe bronchiectasis.

The efficacy and safety of long-term ciprofloxacin therapy in the management of severe bronchiectasis were retrospectively assessed in patients who had taken oral ciprofloxacin continuously for at least 90 days. The drug was well tolerated, with only one reported side effect. Treatment resulted in a symptomatic improvement in seven of the ten patients and significant improvements in peak expiratory flow rate and residual volume. There was a decrease in the number of infective exacerbations from 6.2 +/- 2.9 during 365 days to 0.5 +/- 0.53 during 412 days. Resistance to ciprofloxacin developed in 2 patients with Pseudomonas aeruginosa infection and this was associated with clinical deterioration, but in a further two patients with P. aeruginosa the pathogen was eradicated. Two patients had persistent Streptococcus pneumoniae cultured from sputum but this was not associated with clinical deterioration. The study suggests that ciprofloxacin is effective and safe in the long-term treatment of chronic bronchial sepsis due to bronchiectasis, but emergence of P. aeruginosa resistance is of some concern.