Exhaled markers of oxidative stress in idiopathic pulmonary fibrosis.

BACKGROUND: Expired breath condensate (EBC) has never been used to explore the level of oxidative stress in idiopathic pulmonary fibrosis (IPF). Therefore, the aim of this study was to measure the levels of H2O2 and 8-isoprostane, as biomarkers of oxidative stress, in the EBC of patients with IPF. MATERIALS AND METHODS: We investigated 16 patients with IPF and 15 healthy subjects as the control group. The levels of H2O2 and 8-isoprostane were measured in the EBC of all subjects and were compared between the IPF and control groups. In patients with IPF, H2O2 and 8-isoprostane were further correlated with pulmonary function tests (PFTs), the resting pO2 and the differential cell count from the bronchoalveolar lavage fluid (BALF). RESULTS: The mean (95%CI) concentration of H2O2 was increased in the patients with IPF compared with the normal subjects (0.36, 0.24-0.47 microM vs. 0.16, 0.10-0.23 microM, P=0.003). The mean (95%CI) concentration of 8-isoprostane was also increased in the patients with IPF compared with the controls (74, 38-110 pg mL-1 vs. 33, 28-39 pg mL-1, P=0.02). In the patients with IPF, the diffusing capacity of the lung for carbon monoxide was negatively correlated with the levels of H2O2 in EBC (P=0.03, r=-0.58). No other correlation was found between the oxidative stress markers in the EBC and PFT values, pO2 or BALF cell count. CONCLUSIONS: Our data suggest that H2O2 and 8-isoprostane are increased in the EBC of patients with IPF. H2O2 may be correlated with the severity of the disease in IPF.

The prevalence of congenital bronchial atresia in males.

BACKGROUND: Congenital bronchial atresia is a rare anomaly, which usually occurs in adulthood as an incidental finding on routine chest radiograph. METHODS: The purpose of the study was to retrospectively evaluate the cases that were diagnosed in our hospital, from January 1995 to March 2003, to estimate the prevalence of this disorder and to determine the diagnostic studies of choice, according to the existing literature. Since the main portion of the male population of our country is referred to our hospital for screening soon after their enrollment in the army, epidemiological data can be easily estimated for many congenital anomalies occuring in adulthood, such as bronchial atresia. RESULTS: We found seven patients with Congenital Bronchial Atresia and the prevalence of this disorder was estimated at 1.2 cases per 100,000 in males. The chosen diagnostic procedure is computed tomography of the chest with high-resolution scans. Bronchoscopy would only exclude serious alternative diagnosis and prevent unnecessary surgical interventions. CONCLUSIONS: Congenital bronchial atresia is a rare anomaly, with a mild clinical course. The diagnosis is made radiologically, the HRCT of the chest being the procedure of choice. Bronchoscopy should be performed to exclude any endobronchial lesion due to a different disease entity and to prevent unnecessary surgical intervention in an otherwise asymptomatic individual.

Prostaglandin E2 in the expired breath condensate of patients with asthma.

Inhaled prostaglandin (PG)E2 has been found to cause bronchodilation in asthmatics, although it does not have bronchodilative effects in normal subjects. The aim of this study was to investigate the levels of PGE2 in the expired breath condensate of patients with asthma, the possible contribution of smoking habit to its levels and the possible relationship between PGE2 and the degree of bronchial hyperresponsiveness, as assessed by the provocation dose of histamine causing a 20% fall in forced expiratory volume in one second (FEV1) (PD20). A total of 30 mild asthmatics (15 smokers, all steroid-naive, FEV1 88+/-6 (%+/-SD)) and 20 healthy control subjects (10 smokers) were studied. Histamine challenge testing was performed in all subjects and the PD20 was determined. The results showed that asthmatic smokers had significantly higher values of PGE2 compared to asthmatic nonsmokers and control subjects (40+/-21 versus 14.5+/-4.5 versus 11.7+/-3 pg x mL(-1), respectively). Further analysis showed that PGE2 levels were significantly higher in asthmatic smokers compared to smoker and nonsmoker controls (40+/-21 versus 11.6+/-2 versus 11.7+/-4 pg x mL(-1), respectively). No significant difference was observed between asthmatic nonsmokers and both control smokers and control nonsmokers. No significant correlation was found between PGE2 levels and PD20 in all groups of asthmatics, irrespective of smoking habit. In conclusion, the elevation of prostaglandin E2 in the expired breath condensate of patients with asthma is mainly attributed to smoking habit and prostaglandin E2 levels do not predict the degree of bronchial hyperresponsiveness.

Total nitrite/nitrate in expired breath condensate of patients with asthma.

Production of nitric oxide (NO) is generally increased during inflammatory diseases including asthma. The eventual fate of NO is oxidation to nitrite (NO2) and nitrate (NO3), both of which are end-products of NO metabolism. Hydrogen Peroxide (H2O2) is increased in exhaled breath condensate of asthmatic subjects and may be used as a non-invasive marker of oxidative stress. NO has in some cases been shown to attenuate oxidant-induced lung injury. Total NO2/NO3 concentration and H2O2 levels were measured in expired breath condensate in 50 clinically stable asthmatics [all males, all atopics, mean age 22 (3) SD yrs, forced expiratory volume in 1 sec (FEV1) 91 (10)% predicted, PD20 to histamine 0.262 (0.16) mg 20 on inhaled steroids, 20 smokers, all steroid-naive] and in 10 normal, non-atopic subjects [all males, age 23 (4) yrs, FEV1 101 (14)% predicted, PD20 to histamine 1.3 (0.55) mg]. NO2/NO3 levels were significantly higher in patients with asthma than in normal subjects (1.08, 95% CI 0.86-1.3 microM vs. 0.6; 95% CI 0.46-0.8, P < 0.001). Patients who were on inhaled steroids had significantly ower values compared to steroid-naive (0.71, 95% CI 0.55-0.87 microM vs. 133, 95% CI 1-1.65 microM, P < 0.001). Similar results were observed between smokers and non-smokers (1.11, 95% CI 0.74-1.47 microM vs. 1.77, 95% CI 1.1-24 microM, P < 0.0001). There was a significant positive correlation between NO2/NO3 levels and H2O2 concentration in expired breath condensate (r = 0.48, P < 0.0001). No correlation was observed between NO2/NO3 levels, airway obstruction and bronchial hyper-reactivity as assessed by PD20 to histamine. Total NO2/NO3 levels in expired breath condensate are raised in patients with stable asthma and are significantly related to oxidative stress as assessed by H2O2 concentration. Measurement of expired breath NO2/NO3 and H2O2 levels may be clinically useful in the management of oxidation and inflammation mediated lung injury.

Magnesium levels in plasma and erythrocytes before and after histamine challenge.

Previous studies have assessed the protective effect of nebulized magnesium sulphate on bronchial hyperreactivity. This study investigated the effect of histamine challenge on intracellular (erythrocytes) and extracellular (plasma) levels of magnesium and the possible relationship between degree of bronchial hyperreactivity and levels of Mg in plasma and erythrocytes. The authors studied 42 mildly asthmatic patients (10 on inhaled steroids) and 20 healthy subjects. Histamine challenge was performed by the dosimeter method and provocative dose causing a 20% fall in forced expiratory volume in one second (PD20) (FEV1) was calculated. Mg levels were measured with a calmagite colourimetric assay, both at baseline and when FEV1 had fallen by 20%. The results showed that Mg levels in plasma did not significantly change after histamine challenge (from 2.06+/-0.02 mg x dL(-1) to 2.08+/-0.02 mg x dL(-1) respectively, p=0.14). Conversely there was a statistically significant decrease in Mg levels in erythrocytes between these two time points (from 1.84+/-0.02 fmmol x cell to 1.78+/-0.02 fmmol x cell p<0.0001). Similar results were observed when the subgroups were studied separately. There was no significant correlation between PD20, the difference in both magnesium concentrations (baseline-PD20 time) or the initial values of Mg levels in erythrocytes and plasma. To conclude, histamine challenge reduces magnesium levels in erythrocytes while plasma levels remain unchanged. This histamine-induced decrease in magnesium levels occurs regardless of the diagnosis of asthma, and it is not correlated with the degree of bronchial hyperreactivity.

Eosinophilic granuloma of the lung presenting as an endobronchial mass.

A 19-yr-old male presented with left lung parahilar consolidation and clinical signs of pneumonia. These symptoms were secondary to an endobronchial mass in the apical segment of the lower lobe. At thoracotomy an apical segment bronchial sleeve resection successfully extirpated what later proved to be an endobronchial eosinophilic granuloma. To the authors' knowledge this is the first case report of an endobronchial eosinophilic granuloma in an adult.

Serum concentrations of lignocaine before, during and after fiberoptic bronchoscopy.

BACKGROUND: Lignocaine is commonly used for local anesthesia during fiberoptic bronchoscopy (FOB). Several studies have reported the peak serum concentration of lignocaine in relation to time, but most of them did not specify the administered dose of lignocaine gel and its possible correlation with peak serum concentration. OBJECTIVE: The aim of our study was to record the plasma concentrations of lignocaine before, during and after FOB and to evaluate whether the doses for nasal and tracheobronchial anesthesia have any correlation with the peak serum concentrations of the drug. METHODS: Twelve patients with no comorbid conditions undergoing FOB were studied. Lignocaine was administered as a 2% solution using a larynx syringe, 2% gel (mean dose 182.5 +/- 15 mg) and finally 2% solution through the bronchoscope (mean dose 339 +/- 12 mg). Total dose was 622 +/- 20 mg. Venous blood samples were taken before the beginning of local anesthesia and then at 5, 10, 20, 60, 90 and 120 min thereafter. RESULTS: Our results showed that peak plasma concentrations of lignocaine were observed in 8 patients 20 min after the beginning of local anesthesia, in 3 patients 30 min afterwards and in 1 patient 60 min afterwards (2.15 +/- 0.4 microg/ml, 1.9 +/- 0.3 microg/ml, 1. 81 microg/ml, respectively). None of our patients exceeded the critical level of toxicity (5 microg/ml). Both the total and tracheobronchial doses of lignocaine were significantly correlated with peak serum concentration (r = 0.63, p = 0.05 and r = 0.64, p = 0.02, respectively). No correlation was found between the dose for nasal anesthesia and peak serum concentration. No adverse reactions were observed. CONCLUSIONS: In conclusion our data show that although the amount of lignocaine used in this study exceeded the recommended highest dose (400 mg) in all patients, no toxic levels were observed. Peak plasma concentrations were found within 20-30 min from the beginning of local anesthesia. The dose for the anesthesia of nasal mucosa represented a significant percentage of the total dose, but did not correlate with the peak serum concentration of the drug.

Bacterial pneumonia as a suprainfection in young adults with measles.

The aim of this study was to report the clinical and laboratory characteristics of bacterial pneumonia related to measles infection, and also to assess any correlation between severity and time of onset. Four hundred and twenty-four previously healthy young males (age 22+/-2.1 yrs) were hospitalized with typical symptoms and signs of measles. One hundred and twelve (26%) developed bacterial pneumonia on admission (n=41), during their hospital stay (n=20) or days after their discharge (n=51): groups A, B and C, respectively. Single lobar consolidation was the most common finding, accounting for 89% of cases. Pleural effusion was uncommon and associated in half of the cases with empyema. A microbiological diagnosis was made in 81 cases. Streptococcus pneumoniae (65 cases) and Klebsiella pneumoniae (9 cases) were the most commonly identified organisms. Patients from group C had significantly higher values of white blood cell count and erythrocyte sedimentation rate, and lower values of arterial oxygen tension (14+/-0.8 x 10(9) x L(-1), 88+/-4 mm and 6.3+/-0.4 kPa (47+/-3 mmHg), respectively) than the other two groups. There were no deaths during the hospitalization period. The mean duration of hospital stay was 13+/-2.4 days and was longer in the presence of K. pneumoniae infection (19+/-1.6 days). Six patients from group C were admitted to the intensive care unit. In conclusion, these data suggest that bacterial pneumonia associated with measles is not unusual in hospitalized adults, and it seems to be more severe when it occurs days after the onset of rash.

Evaluation of nasal patency: comparison of patient and clinician assessments with rhinomanometry.

The correlation between the objective measurement of nasal resistance and nasal airflow sensation is usually regarded as poor. The aim of the study was to assess the relation between objective indices of nasal patency, as assessed by the occlusion method (RN) and the Youlten peak nasal inspiratory flow meter (PNIF), with subjective sensations of nasal blockade by either the patient or the clinician in groups of patients with rhinitis, asthma, rhinitis and asthma, nasal septal deformity and ill normal controls. We studied nasal airway patency in 254 subjects (37 women, 217 men), mean age 21 years (range 14-78) by RN and PNIF. Nasal resistance was also measured by the application of Ohm's law for parallel resistors (NRO) by estimating the unilateral resistance separately. Subjective sensation of nasal blockade was assessed either by the patient on a 10-point Borg scale (SUB), or the clinician (CLN) on a 6-point scale (3 for each side of the nose). The latter was done in a controlled fashion with the aid of reference sensations. Adjusting for age, height, smoking status and airway calibre, we found good correlation between RN and CLN (r=0.57, p=10(-4)), whereas the association between RN and SUB was moderate and of borderline significance (r=0.42. p=0.05). By logistic regression analysis, we found that the only independent predictors of abnormal nasal resistance at a cut-off value of 0.30 kPa/l/s were the nasal scores as assessed by the clinician (r-=0.26, odds=2.45). We conclude that PNIF measurement and SUB scores are of limited use as indices of nasal patency, although the latter showed an improved association in comparison to older studies. As there is a necessity for some sort of objective measurement to assess nasal patency, the described clinician evaluation may be clinically useful in place of PNIF, but due to its somewhat subjective nature and its inability to detect milder levels of nasal obstruction it cannot be recommended as an alternative to rhinomanometry.

Multiplex PCR assay for the detection of mycobacterial DNA sequences directly from sputum.

Time consuming classical diagnostic tests and the increasing incidence of tuberculosis epidemics have rendered the need for new more sensitive diagnostic tools, urgent. This study explored the possibility of a direct and rapid method for the identification and characterization of pathogenic typical and atypical species of mycobacteria from sputum, based on a multiplex PCR assay. Gene bank search on the mycobacterial genome revealed specific sequences that fulfilled the above set criteria. Two pairs of primers were used to amplify a 243 bp fragment of the gene encoding the immunogenic protein MPB 64 and a 133 bp fragment of the gene encoding the 65-KDa mycobacterial antigen. The first pair of primers was selected among others, to detect specifically bacteria of the M. tuberculosis complex, whereas the second, to detect in addition to the latter, those of the M. avium-intracellular complex. Our mutiplex PCR assay, detected and identified correctly, all the mycobacterium tuberculosis and M. avium-intracellulare complex strains provided on pure culture as controls with a sensitivity of 10(-3) colony forming units. Furthermore, by performing our assay on 55 sputum samples from patients with positive culture and Ziehl-Neelsen staining, we identified mycobacterial DNA sequences in all--39 samples with M. tuberculosis complex and 16 with M. avium-intracellulare complex. Out of 300 sputum specimens from patients with clinical evidence of tuberculosis, 149 were positive by our method (95 M. tuberculosis and 54 M. avium-intracellulare complex) whereas 157 samples (95 M. tuberculosis complex, 59 M. avium-intracellulare complex, 1 M. xenopi, and 2 that could not be positively identified) were culture positive and only 95 Ziehl Neelsen positive. These findings suggest that the method described can be applied on sputum, and can identify in one step strains of the M. tuberculosis and M. avium-intracellulare complex and has effectivness comparable to culture methodologies.

Lung function in patients with inflammatory bowel disease.

Previous studies on baseline pulmonary function testing (PFT) abnormalities in patients with inflammatory bowel disease (IBD) are conflicting because most of them have incorporated patients suffering from both ulcerative colitis (UC) and Crohn's disease (CD). The aim of the study is to investigate whether any PFT abnormalities could be detected in a large group of IBD patients and whether there are differences between the two IBD entities. A total of 132 patients, 47 with CD (mean age 35 years) and 85 with UC (mean age 40 years) were studied. Pulmonary function tests (PFTs), lung transfer factor for carbon monoxide (TLCO) were examined and compared with those of 36 healthy controls. No significant difference of mean values of spirometric indices, TLCO and ABG was found between the two groups of patients and controls, or between patients with CD and UC. However, nine (19%) patients with CD and 15 (17.6%) with UC had a reduction in TLCO, a percentage significantly higher than in controls (P < 0.05). The majority of the patients with TLCO reduction were in an active phase of disease (P < 0.05). Our results suggest that there is no difference in routine PFTs between UC and CD patients, as well as between both these groups and normal controls. However, TLCO abnormalities related to the degree of disease activity are found in patients with both UC and CD.

Suppressive BALF lymphocyte phenotype in a patient with prolonged stable alveolar proteinosis.

The case history of a 25-year-old man suffering from idiopathic alveolar proteinosis is described. The patient showed a prolonged stable mild disease and a distinct suppressive phenotypic profile of BALF lymphocytes. Specifically, a low T4/T8 ratio and a high percentage of CD11b+ T8 lymphocytes was found. Correlations with disease expression are made.

Association of expression of metalloproteinases and their inhibitors with the metastatic potential of squamous-cell lung carcinomas. A molecular and immunohistochemical study.

Matrix metalloproteinases (MPs) constitute a family of proteolytic enzymes (proteases) that degrade extracellular matrix (ECM) and promote the local or metastatic potential of carcinoma cells, and whose action is restrained by special inhibitors (metalloproteinase inhibitors; MIs). We assessed the role of the MPs stromelysin-3 (STR-3), putative metalloproteinase-1 (PUMP-I), and the gelatinases of molecular weights 72 kDa and 92 kDa, as well as the role of their inhibitors tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2, as markers of metastatic potential in 25 fresh biopsies of squamous-cell lung carcinomas (SCLCs). We examined levels of messenger ribonucleic acid (mRNA) expression for these MPs and inhibitors through Northern blot analysis in 10 carcinomas of high-to-moderate differentiation without lymph-node involvement, and in 15 infiltrative carcinomas of moderate-to-low differentiation with lymph-node involvement. Five cases with significant epithelial atypia and five samples with normal mucosa were used as controls. Expression of STR-3 and TIMP-2 was also assessed immunohistochemically with the avidin-biotin-complex (ABC) technique. We noticed a progressive increase in the expression levels of MPs, especially of STR-3, and of TIMP-2, from the stage of epithelial atypia to the detection of carcinoma, finding the highest values of these substances among carcinomas of low differentiation with nodal metastases. These findings were also confirmed with immunohistochemical analysis. Our results suggest that there is a significant association of the expression of MPs and MIs with both the local and metastatic potential and the degree of cellular differentiation of SCLC, and that this association is clinically important because of its prognostic and therapeutic implications.

Unilateral hypertranslucency of the left hemithorax due to aneurysm of the thoracic aorta.

A 19 year old man presented with a six months history of dyspnoea on exertion. Chest radiographs, isotopic lung scans, and computed tomographic scans of the chest showed unilateral translucency of the left lung, absence of ventilation and perfusion in the same lung, and a 3.5 cm aneurysm of the descending thoracic aorta which compressed the left mainstem bronchus.

Intrapleural streptokinase versus urokinase in the treatment of complicated parapneumonic effusions: a prospective, double-blind study.

Intrapleural administration of fibrinolytics has been shown in small numbers of patients with complicated parapneumonic effusions (CPE) and pleural empyema to be effective and relatively safe. Although streptokinase (SK) is recommended as the fibrinolytic of choice, there are no comparative studies among fibrinolytics. We therefore compared the efficacy, safety, and the cost of treatment two of the most used thrombolytics, SK and urokinase (UK). Fifty consecutive patients with CPE or empyema were randomly allocated to receive either SK (25 patients) or UK, in a double-blind fashion. All patients had inadequate drainage through chest tube (< 70 ml/24 h). Both drugs were diluted in 100 ml normal saline and were infused intrapleurally through the chest tube in a daily dose of 250,000 IU of SK or 100,000 IU of UK. The chest tube was clamped for 3 h after instillation. Response was assessed by clinical outcome, fluid drainage, chest radiography, pleural ultrasound, and/or computed tomography. Clinical and radiologic improvement was noted in all but two patients in each group, who required surgical intervention. The mean volume drained during the first 24 h after instillation was significantly increased; 380 +/- 99 ml for the SK group (p < 0.001) and 420.8 +/- 110 ml for the UK group (p < 0.001). The total volume (mean +/- SD) of fluid drained after treatment was 1,596 +/- 68 ml for the SK group, and 1,510 +/- 55 ml for the UK group (p > 0.05). The SK instillations (mean +/- SD) were 6 +/- 2.16 (range, 3 to 10) and those of UK 5.92 +/- 2.05 (range, 3 to 8). High fever as adverse reaction to SK was observed in two patients. The total cost of the drug in the UK group was two times higher than that of SK ($180 +/- 47 for SK and $320 +/- 123 for UK). The mean total hospital stay after beginning fibrinolytic therapy was 11.28 +/- 2.44 d (range, 7 to 15) for the SK group and 10.48 +/- 2.53 d (range, 6 to 18) for the UK group (p = 0.32). We conclude that intrapleural SK or UK is an effective adjunct in the management of parapneumonic effusions and may reduce the need for surgery. UK could be the thrombolytic of choice given the potentially dangerous allergic reactions to SK and relatively little higher cost of UK.

Adult respiratory distress syndrome due to Chlamydia pneumoniae in a young adult.

A case of life-threatening Chlamydia TWAR pneumonia complicated by encephalitis in a young, previously healthy adult is described. The patient presented with full blown adult respiratory distress syndrome and required prolonged ventilatory support and rigorous antibiotic and supportive care. He recovered fully without any neurologic sequelae. Chlamydia pneumoniae pneumonia should be included in the differential diagnosis of the severe community acquired pneumonia, because if properly sought and adequately treated, may have an excellent outcome.

The varied manifestation of pulmonary artery agenesis in adulthood.

OBJECTIVE: Unilateral pulmonary artery agenesis (UPAA), a rare congenital anomaly that is frequently associated with other cardiovascular abnormalities, is usually diagnosed in childhood. Most patients who have no associated cardiac anomalies have only minor or absent symptoms and survive into adulthood. The conditions of such patients are frequently misdiagnosed in adulthood. In this report, we describe six patients with UPAA in whom the diagnosis was first established in adulthood. The varied clinical presentation of these patients is reviewed and the relative effectiveness of a variety of diagnostic tests is compared. SUBJECTS AND METHODS: During the period January 1987 through December 1990, six male patients, aged 17 to 20 years, were found to have UPAA at the time of their medical screening for enrollment into the armed forces. The diagnosis was based on history, clinical and imaging examinations, including chest radiography, ventilation-perfusion lung scan, digital subtraction angiography (DSA), computed tomography (CT), and magnetic resonance imaging (MRI). RESULTS: In four of the patients, the UPAA was on the left side and in two it was on the right. A right aortic arch was present in three patients and other cardiovascular anomalies were found in three. Pulmonary function studies showed a mild restrictive pattern in four. In contrast to previous reports, the ventilation scan showed a diminished "wash in" and "equilibrium" phase without a delayed "wash out" phase on the affected side in all patients. Selective bronchography through the fiberoptic bronchoscope revealed ipsilateral mixed-type bronchiectasis in two of four patients studied, a finding of clinical significance that has not been described previously. In all cases, the diagnosis was made by DSA. CT of the thorax (n = 6) and MRI (n = 4) were diagnostic in all cases in which they were performed, but added no significant information. CONCLUSION: UPAA is frequently misdiagnosed in adulthood and is often not considered in the differential diagnosis of the unilateral hyperlucent lung. Clinicians and radiologists should be aware of the possibility of undiagnosed cases in adults, with many atypical characteristics.

Tuberculin sensitivity trends in Hellenic army recruits during the period 1981-91.

SETTING: The tuberculin skin test is widely used to define the tuberculous infection in the community. Serial representative tuberculin surveys demonstrate the trend of the risk of tuberculous infection. OBJECTIVE: The study of tuberculous infection in Hellenic army recruits for the purposes of BCG vaccination, which with chemoprophylaxis and early case-finding are the major strategies used for preventing tuberculosis (TB). DESIGN: We investigated tuberculin skin sensitivity on 544210 Hellenic Armed Forces recruits during 1981-91. The age of the subjects ranged between 18-28 years (mean 21 +/- 1.5 years). We used the Mantoux technique with tuberculin PPD-RT 23 with Tween 80, dose 2 IU (1/5000) of the Hellenic Pasteur Institute. Tuberculin skin reactions were examined by two experienced readers after 48 hours. Indurations < 5 mm were considered as negative reactions, > or = 10 mm as positive, and 5-9 mm as doubtful reactions. RESULTS: The results of the present study were compared to other studies undertaken in recruits during the period 1934-80. We found a decrease of positive reactions from 14.2% in 1981 to 6.8% in 1991. The mean annual reduction was 0.74%. The decline has continued since 1947, as previous studies during the period 1934-80 have shown. CONCLUSION: We conclude that the tuberculin reactivity in recruits of the Hellenic army, although still high in relation to other European countries and North America, is declining steadily. We predict that the number of positive reactions will fall to about 1% by the year 2000, assuming that the same trend continues.