Comparative utility of interferon-γ release assay, QuantiFERON® TB-GIT and T-SPOT®.TB in rheumatoid arthritis.

SETTING: National hospital for tuberculosis (TB) and rheumatoid arthritis (RA) in Japan. OBJECTIVE: To compare two interferon-γ release assays (IGRAs), QuantiFERON®-TB Gold In-Tube (QFT) and T-SPOT®.TB (T-SPOT), in RA patients for detecting latent tuberculous infection (LTBI). DESIGN: QFT and T-SPOT were conducted concurrently in 230 prospectively enrolled RA patients. RESULTS: There were no active TB patients. The percentage of QFT- and T-SPOT-positive patients was respectively 8.3% and 5.7%. In patients aged ⩾60 years, these proportions were respectively 12.3% and 7.2%. The percentage of QFT positivity and T-SPOT positivity at age <60 years was respectively 2.2% and 3.3%. After multivariate logistic analysis for QFT positivity, age ⩾60 years and TB suspected based on chest X-ray were selected as independent factors, with adjusted odds ratios of respectively 4.73 and 3.25. No factors were selected for T-SPOT positivity. CONCLUSION: QFT had a higher positivity rate. In the light of the previous estimated rate of LTBI in Japan, both IGRAs underestimate LTBI, and neither IGRA has enough capability to detect LTBI.

[Tuberculosis of the elderly (above the age of 75) in national hospitals].

In Japan tuberculosis is becoming rapidly the disease of the elderly. We studied the background, the type and level of hospital cares needed, and the outcome of patients with pulmonary tuberculosis (sputum smear and/or culture positive) above the age of 75 who were admitted to 8 national hospitals during the period from January 1 to December 31, 1997. The study included 150 patients (male: 109, female: 41, mean age: 81.6), of whom 25% needed care in a single-bed room, 84.3% had underlying diseases (cardiovascular diseases: 43.3%, malignant diseases: 20.9%, neuro-psychiatric diseases: 13.4%), and 47.6% needed cares mainly in feeding and excretions. 92 patients (62.6%) improved and 45 patients (30.6%) died, of whom the cause of death was directly related to tuberculosis in 42. The mean hospital stay was 4.7 months. However, in 42 patients whose cause of death was related to tuberculosis, 66% died within 3 months, while in 102 patients who were discharged 71% stayed more than 3 months. The same comparison was done in 508 patients with bacteriologically proven tuberculosis above the age of 75 admitted to National Tokyo Hospital during the period from 1990 to 1999. The result was almost the same, among 133 patients died in the hospital 60% died within 3 months, while in 375 patients who were discharged hospital stay was more than 3 months in 70%. In the near future, the elderly will occupy more than 25% of the beds of the tuberculosis ward in Japan and most of them have underlying diseases other than tuberculosis. Because tuberculosis, once the disease of the young, is becoming rapidly the disease of the elderly, it is imperative for us to make necessary adjustments to meet this inevitable trend.

[Clinical study on the cases in which INH or RFP was discontinued during treatment for pulmonary tuberculosis].

Short course regimens; 2HRZ (E)(S)/4HR (E), 6HRS (E)/3-6HR and 6-9HR have been accepted as a standard chemotherapy (SC) for initial treatment of pulmonary tuberculosis in Japan. We studied the frequency of the treatment completion, the causes of the treatment failure and the outcome of the patients in whom INH or RFP was discontinued within 6 months after starting SC. The subjects included 597 newly diagnosed culture positive pulmonary tuberculosis patients admitted to 16 national hospital in 1996. Results were as follows. 1. In 47 (7.9%) of the 597 patients, either INH (19; 3.2%) or RFP (33; 5.5%) was discontinued. These 47 cases were defined as a SC incompleted group and the other 550 as a SC completed group. 2. The patients in the SC incompleted group were seen more frequently in the ages of 20s (11.9%), 50s (10.9%), 60s (11.7%) or 70s (11.4%). 21 (13.6%) of 154 female patients and 26 (5.9%) of 443 male patients were in the SC incompleted group. 3. The causes of cessation of INH or RFP were drug side effects (33; 5.5%), drug resistance (10; 1.7%) and complications or underlying diseases (8; 1.3%). 4. Fever or eruption (19; 3.2%) and drug induced hepatitis (12; 2.0%) were frequently seen as drug related side effects causing the cessation of INH or RFP. 5. The rate of culture negative conversion of TB bacilli at 6 months after the start of the treatment was 98.9% in the SC completed and 88.9% in the SC incompleted group respectively. In the SC incompleted group, there were three cases continuously positive and two other patients who relapsed and became culture positive again. In these five patients, INH or RFP was discontinued because of drug resistance.

[A case of Behçet's disease presenting with Hughes-Stovin syndrome (multiple pulmonary arterial aneurysms remitting with corticosteroid therapy)].

A 32-year-old male suffering from thrombophlebitis of the right leg was admitted to our hospital because of massive hemoptysis. Chest radiography showed multiple rounded opacities in the right lung field. Pulmonary angiography revealed multiple aneurysms of the right pulmonary arteries and thromboembolism of the left pulmonary artery. Venography demonstrated obstruction of the deep veins of the right leg and the right femoral vein, and deep vein thrombosis was diagnosed. A more precise diagnosis was Hughes-Stovin syndrome, that is, venous thrombosis especially of the vena cava, accompanied by single or multiple pulmonary arterial aneurysms in young patients. Furthermore, the patient had an aphthous ulcer in the oral cavity, an ulcer in the genital region, leading to a diagnosis of the incomplete type of Behçet's disease. Chest radiographs 3 months after the initiation of corticosteroid showed complete resolution of the aneurysms. Repeated pulmonary angiography also showed partial recanalization of the occluded arteries. This report describes this very rare case of Behçet's disease presenting with Hughes-Stovin syndrome.

[Prevention of development of pulmonary tuberculosis in compromised host].

Recently compromised hosts have increased due to aging of population, advance of medical technology and therapy or changes in the dietary life and social life. Concomitantly the proportion of compromised hosts in the patients with pulmonary tuberculosis has also increased. Taking up diabetes mellitus, hemodialysis, collagen disease and lung cancer as the representatives of compromised hosts, we studied the propriety of chemoprophylaxis to prevent the development of tuberculosis and the standard for the subjects in the case of chemoprophylaxis being given. Diabetics top the patients in the high risk group of developing pulmonary tuberculosis. Therefore, giving chemoprophylaxis is considered necessary to prevent the development of tuberculosis from diabetics. Chemoprophylaxis to diabetics should be given only when healing of tuberculosis has been found despite the history of treatment for tuberculosis being absent. In the patients of hemodialysis, the total morbidity of tuberculosis is high, but the morbidity of pulmonary tuberculosis is not too high, so chemoprophylaxis for the patients on hemodialysis is not always necessary. However, chemoprophylaxis according to the same standard for diabetics is necessary for the patients with diabetic nephropathy. In the patients with collagen disease except rheumatoid arthritis under consideration for administration of corticosteroid preparations, chemoprophylaxis is considered desirable where doses of more than 10 mg in terms of prednisolone are administered over a long period of time. In the patients with lung cancer under consideration for administration of corticosteroid preparations, chemoprophylaxis is considered desirable where doses of more than 10 mg in terms of prednisolone are administered over a long period of time.

[Clinical analysis of multidrug-resistant tuberculosis].

Forty-three patients with multidrug-resistant tuberculosis at National Chiba-Higashi Hospital were studied retrospectively. TB cases excreting tubercle bacilli which are resistant to both 0.1 microgram/ml of isoniazid and 50 micrograms/ml of rifampicin were defined as multidrug-resistant cases. From 1993 to 1997, we experienced 1627 patients with pulmonary tuberculosis, and among them 43 patients (23-79 years old, 35 males and 8 females) were proved to be multidrug-resistant. Six cases were initially treated cases and other 37 cases had been treated previously. On admission, 40 out of 43 cases (93.0%) were smear positive by sputum examination of mycobacteria and 38 out of 43 cases (88.4%) had cavitary lesions on chest X-ray. Six patients were complicated with diabetes mellitus, two with cancer, one with alcohol dependence, one with chronic hepatitis, and others did not have prominent complications. Three operated patients were cured, the fact shows that the surgical treatment is still a useful measure for cases with the indication. Sixteen patients were cured, eight were still under treatment, and thirteen were died of tuberculosis. One of reasons of poor prognosis of multidrug-resistant tuberculosis is that multidrug-resistant tubercle bacilli are usually resistant to other drugs, too. In case of multidrug-resistant tuberculosis, patients were obliged to be treated in a hospital long-term to prevent the spread of tubercle bacilli. Therefore, it is very important to find out new tuberculosis cases as an early as possible, treat them with proper regimen and prevent dropout by directly observed therapy, thus preventing the emergence of multidrug-resistant tuberculosis. Development of new antituberculous agents is strongly expected.

[A clinical study in the collagen disease patients developed pulmonary tuberculosis during corticosteroid administration].

The study subjects consisted of 14 pulmonary tuberculosis (PTB) patients with collagen disease. They are under corticosteroid treatment and the mean age is 56.4 years. The length of time from the development of collagen disease to the development of PTB averaged 4.1 years. The breakdown of collagen disease are SLE (6 patients), MCTD (3 patients), PN (2 patients), and PSS, PM, Sjogren syndrome (1 case, each). Thirteen cases were bacilli positive by the sputum examination on admission to our hospital. Chest X-ray findings on admission revealed cavitation in 3 cases and non-cavitation in 11 cases, of which 5 cases had miliary tuberculosis. Corticosteroid preparation had been administered to all of the 14 cases for more than one year. The mean dose of corticosteroid preparation administered when PTB developed was 13.9 mg (prednisolone) and it was more than 20 mg in 8 cases. The median duration from the start of the respiratory symptoms to diagnosis was 39.2 days. The delay in the discovery exceeding 1 month were seen in 9 cases. In the cases of collagen disease, when the disease course extends over a long period of time, and even when the dose of corticosteroid preparations are decreased, there is a need to be note on the risk of developing PTB. There are many non-cavitary cases with sputum smear positive. The fact suggested that an appropriate diagnosis is need so that the discovery of PTB should not be delayed.

[A study of patient's and doctor's delay in patients with pulmonary tuberculosis discovered by visiting doctors with symptoms in particular on doctor's delay].

Epidemiological trend of tuberculosis in Japan has reversed recently. The incidence of pulmonary tuberculosis (PTB) patients has increased again in Japan, and many outbreaks of PTB including nosocomial outbreaks in health-care facilities have been reported. The purpose of this study is to investigate patient's delay (interval between onset of the disease and first visit to a doctor) and doctor's delay (interval between first visit to a doctor and diagnosis as TB) in patients with PTB discovered by visiting doctors with symptoms, and especially, to investigate causes of doctor's delay in details. Of 236 PTB patients who were admitted to our hospital for treatment in 1997, 118 patients (85 males, 33 females) who were detected by their symptomatic visits were enrolled in to this study. 97 were initial treatment cases and the others were re-treatment cases. Among 34 initial treatment cases who were first seen at a general hospital and diagnosed as PTB by a close medical checkup after admission to our hospital, the 50 percentile of patient's delay was 17.0 days, and the 80 percentile was 36.4 days. The 50 percentile doctor's delay was 19.6 days, and the 80 percentile was 64.2 days. The average hospital stay was 16.2 days, the 50 percentile hospital stay was 7.8 days, and 80 percentile hospital stay was 23.5 days. On the sputum test for acid fast bacilli (AFB) performed on admission to our hospital, 26(76%) out of 34 cases were positive for tubercle bacilli, with 18 cases were positive for smear and 8 cases positive for culture. Therefore, risk of nosocomial infection was suspected. Doctor's delay had been attributed mainly to insufficient medical checkup. Among 25 initial treatment cases in whom doctor's delay as more than 4 weeks, 11 cases (44%) showed delay in chest X-ray examination and 8 cases (32%) ordered no sputum examination in spite of recognition of abnormal shadows on chest X-ray. On the sputum test for AFB on admission to our hospital, 22 (88%) out of 25 cases were positive for tubercle bacilli. Therefore, it is assumed that the delay in the adequate medical checkup was accountable for the doctor's delay. Shortening of the doctor's delay could be possible if hospitals perform the sputum examination for AFB and chest X-ray examinations properly for patients with respiratory symptoms.

[Management of pulmonary tuberculosis patients complicated with diabetes mellitus before diagnosis as pulmonary tuberculosis and feasibility of chemoprophylaxis].

We studied whether diabetics who are one of the high risk groups of developing pulmonary tuberculosis had undergone chest X-ray examination periodically. The feasibility of chemoprophylaxis in diabetics was also studied by investigating whether fibrotic lesions of tuberculosis can be found on previous chest X-ray films of these patients. Of the pulmonary tuberculosis patients admitted to our hospital for treatment, 78 patients complicated with diabetes mellitus were enrolled in this study. As to the mode of detection, the majority, 63 cases, are discovered, by undergoing medical examination because of respiratory symptoms, followed by 8 patients in whom pulmonary tuberculosis was found by health examination and only 1 patient was found by the periodic observation of diabetes mellitus. Of the 57 patients receiving the original treatment for pulmonary tuberculosis preceded by the discovery of diabetes mellitus, only 15 (26%) had undergone chest X-ray examination periodically. This fact shows that physicians treating diabetes mellitus have only a little concern on tuberculosis, thus the re-training of physicians dealing with diabetics on tuberculosis is considered to be necessary. According to chest X-ray films of 21 patients who had undergone chest X-ray examination and in whom the previous films were available, there were 6 patients without any lesion of pulmonary tuberculosis, 8 patients with fibrotic lesions and 7 patients with active lesions. The 8 patients showing fibrotic lesions have developed pulmonary tuberculosis on the average 15 years after they were diagnosed with diabetes mellitus, and the fact suggests that the prevention of the development of pulmonary tuberculosis among diabetics could be possible by chemoprophylaxis.

[The complication with tuberculosis of the central nervous system in patients with miliary tuberculosis].

The complication with tuberculosis of the central nervous system (CNS) were studied in 16 patients with miliary tuberculosis who were admitted to our hospital during a period of two years from April, 1997 to March, 1999, and were examined by head MRI. Twelve cases (75%) were diagnosed as having tuberculosis of CNS. Six cases had tuberculosis of CNS which was found during the screening of miliary tuberculosis cases, and all had only cerebral tuberculoma. Meningeal irritative symptoms led to the discovery of tuberculosis of CNS in the remaining six cases, in which cerebral tuberculoma was complicated with tuberculous meningitis. Of these cases of meningitis, three cases showing disturbance of consciousness died, but no cases of death was found in cases by the screening. The length of time from the onset of symptoms to the diagnosis of tuberculosis was long in many of the cases complicated with tuberculosis of CNS compared with the cases without such a complication. In the cases of miliary tuberculosis, the rate of complication with tuberculosis of CNS is high, and the possibility of patients developing serious symptoms suddenly even when they were asymptomatic at the time of diagnosis and the paradoxical expansion that becomes intensified after initiation of treatment have been reported. Therefore, it is necessary to make a close checkup of CNS when the diagnosis of miliary tuberculosis has been made.

[Frequency of complication of diabetes mellitus in pulmonary tuberculosis].

The frequency of complication of diabetes mellitus in patients with pulmonary tuberculosis is high, and the presence of diabetes mellitus plays an important role in the development of pulmonary tuberculosis. We studied the frequency of complication of diabetes mellitus by year, sex and age among patients with pulmonary tuberculosis who were discharged from our hospital during a period of 12 years from 1987 to 1998. The number of diabetic cases in patients with pulmonary tuberculosis was 588, namely 14.1% out of 4169 patients during the 12 years from 1987 to 1998. The frequency of complication of diabetes in every four years period showed an increasing trend; 144 cases (11.8%) out of 1225 cases from 1987 to 1990, 208 cases (14.5%) out of 1434 cases from 1991 to 1994, and 236 cases (15.6%) out of 1510 cases from 1995 to 1998. By sex, the frequency of complication with diabetes mellitus in male was about twice that of female, with 501 cases (16.0%) out of 3127 cases in male and 87 cases (8.3%) out of 1042 cases in female. By age, the frequency of complication of diabetes mellitus showed a peak in the 40s and 50s in male, being 21.3% and 23.4% respectively. In female, it showed a peak in the 60s, being 18.5%. In conclusion, in the 12 years the frequency of complication of diabetes mellitus in tuberculosis cases has been increasing, and the presence of diabetes mellitus has been playing more important role in the development of pulmonary tuberculosis.

[A case of pulmonary tuberculosis with acute renal failure caused by readministration of rifampicin].

We report a case of pulmonary tuberculosis with acute renal failure caused by readministration of Rifampicin (RFP). A 73 year-old man was admitted to a certain hospital complaining with dyspnea on exertion. As his sputum smear was positive for acid-fast bacilli, he was transferred to our hospital for the isolation and treatment. He was diagnosed as lung tuberculosis and was administrated RFP, Isoniazid (INH) and Ethambutol (EB). On the 20th day after the initiation of treatment, the administration of drugs were suspended, because of liver dysfunction. After recovery of liver dysfunction, we have readministered antituberculous drugs, starting with EB, then INH, and finally RFP. On the 22nd day after the readministration of RFP, acute renal failure was observed. All medications were suspended and we started treatment with hydration and furosemide. His renal function recovered after 7 weeks. Histopathological examination of the kidney revealed interstitial infiltration and tubular nephritis. According to the histopathological examination and the clinical course, we concluded acute renal failure was induced by the readministration of RFP. This case suggests that we have to pay attention to renal side effect of RFP in the course of readministration.

[Investigation of pulmonary hemodynamics and chest X-ray findings in hypercapnic patients with pulmonary tuberculosis sequelae].

We investigated pulmonary hemodynamics and chest X-ray findings to explore pathophysiological significance of chronic hypercapnia in patients with pulmonary tuberculosis sequelae. One hundred and seven patients underwent examinations of blood gases and right cardiac catheterization. The patients were divided into two groups, according to arterial carbon dioxide tension under room air breathing (PaCO2). Group I (n = 35) was defined as 45 Torr or lower of PaCO2, and Group II (n = 72) was the hypercapnic group whose PaCO2 was over 45 Torr. In addition, spirometry was done in 34 patients of Group I and 68 of Group II. First, the values of blood gases, spirometry and pulmonary hemodynamics were compared between the two groups. Secondly, between 22 of Group I and 50 of Group II, the values of pulmonary arteriolar resistance (PAR) before and after 100% oxygen breathing for 10 minutes were compared. These comparisons were made by exploratory data analysis. Lastly, we described in all cases with five items of chest X-ray findings and the extent of each finding we had defined. The items were emphysematous change; fibrosis, bronchiectasis, and/or cavity (hereafter abbreviated as "fibrosis"); lung resection and/or atelectasis; pleural thickening; and thoracoplasty. We explored the items of X-ray findings which may relate to hypercapnia by ridit (abbreviation for "relative to an identified distribution") analysis. The results were as follows. (1) Hypercapnic patients tended to have severer restrictive ventilatory impairment and hypoxemia. Under an even level of arterial oxygen tension (PaO2), tissue oxygenation was not poorer in Group II than in Group I. (2) Hypercapnic patients tended to have more unfavorable pulmonary hemodynamics. More than half of them had pulmonary hypertension defined as 20 mmHg or higher of pulmonary artery mean pressure (PAm). Under an even level of PaO2, PAm was higher in Group II. Although 34 patients of Group II showed PaO2 over 60 Torr, 23 of them had pulmonary hypertension. (3) PAR after oxygen breathing was more likely to decrease in Group II than in Group I. (4) As any mean ridit was standardized and adjusted to 0.5 in Group I, the maximum was the mean ridit of "pleural thickening" (= 0.67), next "fibrosis" (= 0.65) in Group II. The above two items of X-ray findings, in which each mean ridit was higher than in any other item, were more influential on hypercapnia. We conclude as follows. (1) Pulmonary hypertension is severer in hypercapnic patients with pulmonary tuberculosis sequelae; it may be mainly attributable to hypoxic pulmonary vasoconstriction. (2) An important cause of chronic hypercapnia may be pathological changes such as "pleural thickening" and "fibrosis" seen on the radiogram.

[Outbreak of multidrug-resistant Mycobacterium tuberculosis infection in the middle and advanced age].

We experienced a small outbreak of multidrug-resistant Mycobacterium tuberculosis infection (MDR-TB) among persons of in the middle and advanced age. The index case was 48-year-old man, and had complained productive cough since January 1996. He visited a doctor due to his symptom, and chest X-ray revealed cavitary lesion and sputum smear was positive for tubercle bacilli. He could not continue his admission because of his absence without leave and drinking, he was discharged on Day 54. The drug resistance was observed for INH (0.1 microgram/ml), RFP, and SM. Later, case 2, 52-year-old male, and case 3, 43-year-old-male, who were companions in mah-jongg with the index case, were diagnosed as pulmonary tuberculosis. The analysis of restriction fragment length polymorphism (RFLP) was done on 3 strains, and all showed the same pattern. Among other companions in mah-jongg with the index case, case 4, 28-year-old male, was treated as MDR-TB, and the drug resistance pattern was the same to that of the index case, but the details were unknown. Case 5, 65-year-old male, was diagnosed as drug sensitive pulmonary tuberculosis, thus he might incidentally suffer from pulmonary tuberculosis at the same time. Case 6, 46-year-old male, who had been treated for alcoholic liver cirrhosis, was introduced to our hospital as his sputum smear was positive, and the drug resistance pattern was observed similar to that of the index case. All the companions in mah-jongg suffered from MDR-TB except case 5. The RFLP analysis showed that the index case, case 2, and case 3 were caused by the same strain of M. tuberculosis. The drug resistance pattern of, case 4 and case 6 was the same to that of the index case. Based on these findings, it is highly suspected that this small outbreak was originated from the index case.

[Tuberculosis microepidemic in a commuter bus].

A tuberculosis microepidemic in a commuter bus was reported. Index patient was a 22-year-old woman who was an employee of an electronic company. An abnormal shadow was found on her chest roentgenogram during an annual medical check-up in June, 1996. As her sputum smear was Gaffky 6, she was admitted to our hospital for medication. Extraordinary examinations including PPD skin test and chest X-ray were carried out on 49 employees of the company in October, 1996. As the result of these examinations, the distribution of maximum diameters of erythema in PPD skin test showed bimodal distribution, and tuberculosis was discovered in two patients by Chest X-ray examination. Moreover, preventive administration of Isonicotinic acid hydrazide (INH) was indicated for 3 employees based on very strong skin reaction to PPD. These five employees were working separately from the index patient and had little contact with the patient in the work places, but using a same commuter bus. Therefore, we strongly suspect that they were infected from the index patient not in the work place but in the commuter bus. The air-conditioning of the bus used a closed recirculation system, hence insufficient ventilation in the bus contributed to the spread of tuberculosis infection.

[A case of pulmonary tuberculosis case with pancytopenia accompanied to bone marrow gelatinous transformation].

A 45-year-old man did not visit a doctor in spite of his complains, cough and sputum lasting, for six months, and he finally could not eat without beer, and as a result, he lost his body weight and currently 52 kg. He became unconsciousness, was carried to a hospital, and was referred to our hospital. His sputum examination for acid fast bacilli was smear positive, Gaffky 6, for M. tuberculosis. His chest roentogenogram revealed large cavitary lesions in bilateral lung fields. On blood examination, WBC was 1100/microL, RBC was 256 x 10(4)/microL, and PLT was 13.4 x 10(4)/microL. Total protein was 4.7 g/dl, albumin was 1.9 mg/dl, and total cholesterol was 65 mg/dl. We tried to aspirate bone marrow from his sternum, but it was impossible. Hence we did biopsy of his ilium. The pathology of his bone marrow revealed gelatinous transformation. It was thought that the marked delay in visiting a doctor caused general consumption and loss of apetite, thus led to gelatinous transformation and finally pancytopenia.

Loss of heterozygosity of 14q32 in colorectal carcinoma.

Previous allelotyping studies on colorectal carcinoma suggest that loss of heterozygosity (LOH) on chromosome 14q may be a common genetic alteration in this tumor type. The purpose of this study was to determine precise frequency of LOH at 14q32 region in colorectal carcinomas and to define a minimal region of LOH. LOH at 14q32 in 66 primary colorectal carcinomas were analyzed by polymerase chain reaction-based deletion mapping using six highly polymorphic microsatellites. The average rate of informative data was 68.2% in all cases of colorectal carcinoma analyzed. The average rate of LOH at 14q32 was 44.1%, with the highest frequency of 50.0% at D14S267 locus in the informative cases. The minimal region of LOH was defined by markers D14S65 and D14S250 at 14q32. The present data provide useful information for the isolation of tumor suppressor genes from this region.

[Investigation of pulmonary hemodynamics and chest X-ray findings in patients with pulmonary tuberculosis sequelae and obstructive ventilatory impairment].

We investigated pulmonary hemodynamics and chest X-ray findings to explore significance of obstructive ventilatory impairment in patients with pulmonary tuberculosis sequelae. One hundred and two patients underwent examinations of blood gases, spirometry, and right cardiac catheterization. The patients were divided into two groups, according to forced expiratory volume in one second as the percentage of forced vital capacity (FVC), which was expressed as FEV1%. Group A (n = 38) had FEV1% of 55% or lower and Group B (n = 64), FEV1% above 55%. First, the values of blood gases and hemodynamics were compared between the two groups, regarding the percent predicted value of FVC as a covariate. Secondly, between 26 of Group A and 42 of Group B, the change of pulmonary arteriolar resistance (PAR) before and after 100% oxygen breathing for 10 minutes was compared. These comparisons were made by exploratory data analysis. Lastly, we described every case with five items of chest X-ray findings and the extent of each finding we had defined. The items were emphysematous change; fibrosis, bronchiectasis and/or cavity; pulmonary resection and/or atelectasis; pleural thickening; and thoracoplasty. We explored X-ray findings influenced on airway obstruction by ridit (abbreviation for "relative to an identified distribution") analysis, taking smoking status into consideration. The results were as follows. (1) The patients of Group A tended to show severer hypoxemia and tissue hypoxia than the patients of Group B. (2) The patients of Group A tended to show worse values of pulmonary hemodynamics than the patients of Group B. Under an even level of the arterial oxygen tension that was 60 Torr or lower, pulmonary artery mean pressure was higher in Group A than in Group B. (3) PAR after oxygen breathing was less likely to decrease in Group A than in Group B. (4) As any mean ridit was standardized and adjusted to 0.5 in Group B, every mean ridit of "emphysematous change" in Group A was the largest-0.63 in non-smokers, 0.74 in ex-smokers and 0.70 in current smokers. Therefore, "emphysematous change" was more influenced on airway obstruction than any other finding because of the largest mean ridit. We conclude as follows. Pulmonary hypertension is more serious in patients suffering from severe airway obstruction with pulmonary tuberculosis sequelae, and it may be attributable to reduction in capacity of anatomical pulmonary vascular bed rather than hypoxic pulmonary vasoconstriction. Pathological changes such as "emphysematous change" on the radiograph might be considered as an important cause of obstructive ventilatory impairment.

[An outbreak of Mycobacterium tuberculosis infection among young adults in close contact].

We experienced an outbreak of tuberculosis among young adults in close contact. The index case (case 1) was 22-year-old builder and was symptomatic for 9 months before diagnosis as pulmonary tuberculosis (PTB). His sputum smear was positive for tubercle bacilli. On immediate family contacts examination carried out at our hospital, his brother and sister (case 3, case 4) were detected as having PTB. His mother (case 5) and father (case 6) were later detected as having PTB by their symptomatic visits after some months, as tuberculin test as not done at first examination. Case 7 was 19-year-old-man, and was undiagnosed for 5 months. His sputum smear was positive. Immediately, contacts examination for case 7 as carried out at our hospital, and his colleague (case 8) was detected as having PTB. By interview with the case 7, it was found that the case 1 and the case 7 were close friends and spent long time together. Case 10 was 30-year-old builder, and he was accidentally referred to our hospital and was diagnosed as PTB. By the interview with the case 10, it was found that the case 1 and case 10 were members of builders group. This fact was informed to the F health center, and contacts examination for other members of the group were carried out by the F health center, and two young men were detected as having PTB. Analysis of restriction fragment length polymorphism (RFLP) showed that the case 1, the case 5, the case 7, and the case 10 were caused by the same strain of M. tuberculosis. Based on these findings, it is highly suspected that this outbreak was origined from the case 1, and 13 developed tuberculosis and 13 were primarily infected among contacts. The characteristics of this outbreak was that the family and contacts examination were enforced and most of the cases were detected at our hospital. If the outbreak of tuberculosis highly suspected, physicians should actively cooperate with health centers for contacts examination.