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N Siafakas

Publications and source records attributed to N Siafakas.

34 records · Page 2Linked to original sources
PubMed1997

Diagnostic value of ferritin, haptoglobin, alpha 1-antitrypsin, lactate dehydrogenase and complement factors C3 and C4 in pleural effusion differentiation.

Searching to define diagnostic criteria for malignant and non-malignant pleural effusions, the differential diagnostic value of ferritin (FRT), haptoglobin (Hp), alpha 1-antitrypsin (alpha 1-AT), lactate dehydrogenase (LDH) and complement factors C3 and C4 were investigated prospectively in 100 consecutive patients with pleural effusions of various aetiologies. Pleural effusion FRT, C3 and C4 concentrations were found to be useful in differentiating exudates from transudates, so that transudates practically could be excluded in pleural effusion: serum FRT ratio lower than 0.5 and/or in pleural effusion values for C3 and C4 higher than 300 mg dl-1 and 70 mg dl-1, respectively. A pleural effusion: serum C3 ratio greater than 2 is seen only in malignant effusions. No discriminative pleural: serum ratio could be found in FRT and C4 values capable of differentiating malignant from non-malignant effusions. Pleural effusion alpha 1-AT and LDH values were elevated in exudates, as compared with transudates, and had an excellent sensitivity and predictive value, but low specificity, in differentiating malignant from non-malignant effusions. Finally, the sensitivity, specificity and positive predictive value of pleural effusion Hp concentrations were lower than those of FRT and complement factors C3 and C4, respectively.

Adult↗
PubMed1996

Natural history of patients with pulmonary metastases from uterine cancer.

BACKGROUND: Endometrial cancer is the most common female genital cancer and approximately 90% of the cases are diagnosed while they are still confined to the uterus. However, the natural history and treated course after the development of pulmonary metastasis (PM) have not been studied systematically in a large series of patients. METHODS: Between 1962 and 1992, 100 patients (6%) with PM were identified by computerized search of the medical records from 1.665 patients admitted to our hospitals with the diagnosis of uterine cancer. The median age of the patients was 65.5 years (range: 42-87 yrs). The usual histologic types of the uterine neoplasms were 59 adenocarcinomas (59%), 21 sarcomas, and 14 adenosquamous carcinomas. Of the 83 patients with reported tumor grade, 11 had Grade 1 tumor, 12 Grade II, and 60 Grade III. RESULTS: Lung metastases were found at the time of diagnosis of the primary tumor in 22 patients. Hemoptysis was the first symptom of 3 of the 22; the majority had no respiratory symptoms. In the remaining 78 patients with PM appearing after primary therapy, the mean interval time between primary diagnosis and PM was 29.4 months, whereas between PM and death was 15.7 months. Of all patients with lung metastases, 75% did not survive 1 year; however 6% survived more than 5 years after diagnosis of metastatic disease. Patients with isolated PM had prolonged survival (36.1 mos, P=0.001), whether treated medically or with pulmonary resection. Progestin therapy was given to 39 patients, with complete response consisting of radiographic resolution of all disease in 6 patients (15%) and prolonged stabilization in an additional 5 (13%). The histologic grade of the primary tumor was predictive of clinical response to progestine therapy. CONCLUSIONS: Asymptomatic pulmonary metastases represent a common site of extra pelvic spread of disease. The majority of patients with PM (75%) do not survive 1 year. Low grade uterine tumors are more likely to respond to progestin therapy and do so for extended periods of time.

Adenocarcinoma↗
PubMed1996

Intrapleural urokinase in the treatment of complicated parapneumonic pleural effusions and empyema.

Intrapleural urokinase has not been evaluated systemically in terms of efficacy, safety, and cost of treatment in a large series of patients with complicated (parapneumonic) pleural effusions (CPE) and pleural empyemas (PE). Furthermore, the optimal dose and duration of treatment is not known. Twenty consecutive patients with multiloculated parapneumonic effusions (13 with CPE and 7 with PE), in whom a single chest tube failed to drain the fluid, were studied prospectively. The age of the patients ranged 15-92 yrs (median 51 yrs). Urokinase was administered intrapleurally, in a low single daily dose of 50,000 U in 100 mL normal saline via the chest tube. Previous intrapleural instillation of 100 mL normal saline failed to promote drainage in all patients. Urokinase enhanced drainage in all patients. Clinical and radiological improvement was noted in all but one patient. The mean (SD) volume of fluid significantly increased in the first 24 h post-urokinase (p<0.001). The number of urokinase instillations ranged 3-7 (median 5). Radiological evaluation showed excellent improvement in 13 of the 20 (65%) patients. Urokinase was well-tolerated in all patients. The clinical course of patients was uneventful at a mean follow-up of 15 months (range 6-30 months) later. Mean total cost of treatment was $530 +/- 34.6. Our results show that intrapleural instillation of small doses of urokinase is a cost-effective and safe mode of treatment of complicated pleural effusions and pleural empyema and could be the fibrinolytic of choice.

Adolescent↗
PubMed1995

The Tay-Sachs disease prevention program in Australia: Sydney pilot study.

OBJECTIVES: To determine the frequency of heterozygous carriers of the Tay-Sachs disease gene in an asymptomatic Ashkenazi Jewish population and to compare the acceptability of different community testing strategies. DESIGN: Pilot survey of carrier rates and community attitudes. SETTING: Sydney, February 1993 to November 1994. PARTICIPANTS: 147 self- or medically referred people of Ashkenazi Jewish origin were tested. Jewish religious, medical and community organisations and leaders were consulted. OUTCOMES: Prevalence of HEXA mutations, client and community preference for different testing and reporting strategies. RESULTS: Frequency of heterozygous carriers was 1 in 18, with a relative frequency of the three major allelic variants similar to that in overseas studies. Most subjects were medically referred and preferred individual reporting of their carrier status. Community representatives had serious reservations about this strategy and few orthodox Jews participated in the study. An alternative strategy was developed for future testing. CONCLUSIONS: Frequency of heterozygous carriers of the Tay-Sachs disease gene was higher than found among Ashkenazi Jews in other countries, possibly because of ascertainment bias. A testing strategy with medical referral and individual reporting of carrier status may not be appropriate for all the community at risk and a modified strategy is necessary.

Genetic Testing↗
PubMed1995

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.

Adolescent↗
PubMed1995

Probability and characteristics of human immunodeficiency virus infection in male Greek military personnel with tuberculosis.

The probability of an AIDS patient being infected with tuberculosis (TB) has been studied in different populations and found to be increased by as much as 500 times, but the reverse, i.e. the probability of a patient with TB being infected with HIV, has not been studied. The aim of this study was to investigate the hypothesis of greater HIV seropositivity and altered immune status, as indicated by CD4+ T-lymphocyte counts, in TB patients. We prospectively studied 162 males, aged 18-30 years, hospitalized for active, proven TB. Serum for HIV antibodies was tested twice by ELISA and confirmed by the Western blot technique. The control group consisted of 145,000 blood donor volunteers serving in the army, aged 18-30 years. The number of CD4+ T lymphocytes was also measured in the patients and the control group. We found that the rate of HIV seropositivity in TB patients was 2.4% (4 of 162), while it was 0.214% in the control group (p < 0.0001). Using the Bayes' theorem we found that the probability of a TB patient being infected with HIV was 9.1%, approximately 150 times higher than the expected rate in the matched control group (p < 0.0001). The number of CD4+ T lymphocytes was significantly lower in pulmonary and extrapulmonary TB patients than in the control group, taking into account the HIV status (p < 0.001). Our results suggest that there is a 150 times greater probability of a TB patient being infected with HIV. CD4+ T lymphocytes are significantly lower in all groups of TB patients.

AIDS-Related Opportunistic Infections↗
PubMed1995

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.

Adolescent↗
PubMed1994

Role of streptokinase in the treatment of acute loculated parapneumonic pleural effusions and empyema.

BACKGROUND: Intrapleural administration of streptokinase has been shown in a few small series to be effective treatment for complicated parapneumonic effusions and pleural empyemas, but techniques of instillation of streptokinase differ. The role of streptokinase in promoting drainage was investigated prospectively in a larger series of patients with complicated parapneumonic effusions and pleural empyemas. METHODS: Twenty consecutive patients with parapneumonic effusions, 15 with complicated parapneumonic effusions and five with pleural empyemas, drawn from 160 patients presenting with pleural effusions were studied. The age of the patients ranged from 15 to 92 years. Initial thoracocentesis showed mean (SD) values of pH 7.1 (0.15), glucose 45.9 (17.5) mg/dl, white blood cell count 12,000 (6627)/mm3. Streptokinase was administered intrapleurally in a single daily dose of 250,000 units in 100 ml normal saline via the chest tube once the drainage was < 100 ml/24 hours. Patients were treated for 3-10 (mean 6) days. RESULTS: Following administration of streptokinase a clinical and radiological improvement was noted in all but one patient who died on the fourth day of hospitalisation due to widespread adenocarcinoma. Another patient with clinical but minimal radiological improvement underwent thoracotomy, but a clear pleural space with only fibrotic changes was found. The mean (SD) volume of fluid drained 24 hours before streptokinase was 42.5 (39) ml, which increased in the first 24 hours after streptokinase to 334 (130) ml. Radiological evaluation showed an excellent improvement in 14 of the 20 patients, a moderate improvement in three, and minimal improvement in the remaining three patients. One patient developed a high fever as an adverse reaction to streptokinase. All 19 patients who completed the treatment were well at follow up 6-30 months (mean 15 months) later. CONCLUSIONS: Intrapleural instillation of streptokinase is an effective and safe mode of treatment for complicated parapneumonic effusions and pleural empyemas and alleviates the need for thoracotomy.

Adolescent↗
PubMed1992

The role of inexperience in measuring tuberculin skin reaction (Mantoux test) by the pen or palpation technique.

We have shown previously that experienced readers can use the palpation or pen method for reading the Mantoux tuberculin skin test with accuracy. In order to investigate if the inexperienced reader can use both methods with the same degree of accuracy, we performed Mantoux tests in 539 healthy subjects, aged 20-57 years (mean 33 years), using the PPD-RT 23 in dose 2 I.U. (1/5000). In random order and a double-blind fashion, an experienced and an inexperienced reader measured the induration after 48 h by the palpation method initially and then by the pen method, without knowing the identity of the subject. Results of the study did not show any significant difference in any range of measurements by the two readers, using either the pen or palpation method (P greater than 0.1). A highly statistically significant linear relationship was found between the measurements by the pen method used by experienced and inexperienced readers (r = 0.823, P less than 0.0001) and between the palpation measurements by the two readers (r = 0.939, P less than 0.0001). We conclude that the effects of an inexperienced examiner in the measurement of of tuberculin skin induration are minimal. Inexperienced readers can use the pen method as accurately as the traditional palpation method.

Adult↗
PubMed1991

Palpation vs pen method for the measurement of skin tuberculin reaction (Mantoux test).

In order to test the degree of concordance between ballpoint pen and palpation methods of measuring the skin induration after a Mantoux tuberculin test, we conducted a prospective, double-blind study. We performed a Mantoux skin test in 1,340 healthy subjects, aged 18 to 25 years, using the tuberculin PPD-RT 23, dose 2 IU, (1/5,000), of the Pasteur Institute, equivalent to 5 TU PPD-S. The same experienced reader, who was able to see only the site of the test (forearm), measured the induration after 48 hours by the palpation method, initially, and by the pen method later the same day, without knowing the identity of the examined person. Results of the study did not show any significant difference in any range of the measurements (p greater than 0.1) by the two methods. We conclude that the pen method is as reliable as the traditional palpation method. The sensitivity and the specificity of the two methods are comparable. Even though our study was not designed to investigate the effects with an inexperienced examiner, given the simplicity of the pen method, it could be the method of choice, especially for less experienced examiners.

Adolescent↗
PubMedDate not supplied

Effect of different levels of pressure support and proportional assist ventilation on breathing pattern, work of breathing and gas exchange in mechanically ventilated hypercapnic COPD patients with acute respiratory failure.

BACKGROUND: Proportional assist ventilation (PAV) has been shown to maintain better patient-ventilator synchrony than pressure support ventilation (PSV); however, its clinical advantage regarding invasive ventilation of COPD patients has not been clarified. OBJECTIVES: To compare the effect of PAV and PSV on respiratory parameters of hypercapnic COPD patients with acute respiratory failure (ARF). METHODS: Nine intubated hypercapnic COPD patients were placed on the PAV or PSV mode in random sequence. For each mode, four levels (L1-L4) of support were applied. At each level, blood gases, flow, tidal volume (VT), airway pressure (Paw), esophageal pressure (Pes) (n = 7), patient respiratory rate (fp), ventilator rate (fv), missing efforts (ME = fp - fv) were measured. RESULTS: We found increases in ME with increasing levels of PSV but not with PAV. PO2 and VT increased whereas PCO2 decreased significantly with increasing levels of PSV (p < 0.05). With PAV, PCO2 decreased and VT increased significantly only at L4 whereas PO2 increased from L1 to L4. Runaways were observed at L3 and L4 of PAV. The pressure-time product (PTP) was determined for effective and missing breaths. The mean total PTP per minute (of effective plus missing breaths) was 160 +/- 57 cm H2O/s.min in PSV and 194 +/- 60 cm H2O/s.min in PAV. CONCLUSION: We conclude that in COPD patients with hypercapnic ARF, with increasing support, PSV causes the appearance of ME whereas PAV develops runaway phenomena, due to the different patient-ventilator interaction; however, these do not limit the improvement of blood gases with the application of both methods.

Acute Disease↗
PubMedDate not supplied

Patterns of pulmonary metastasis from uterine cancer.

BACKGROUND: Endometrial cancer is the most common female genital cancer and approximately 90% of the cases are diagnosed while they are still confined to the uterus. However, the frequency and the pattern of pulmonary metastasis (PM) have not been studied systematically. PATIENTS AND METHODS: From 1962 to 1989, 90 patients wit PM were identified by computerized search of the medical records of the 1,550 (5.8%) patients admitted to the Massachusetts General Hospital with the diagnosis of uterine cancer. The median age of the patients was 67 years (range from 42 to 88 years). The histology of the uterine neoplasms included 53 adenocarcinomas (59%), 19 sarcomas (21%), 12 adenosqamous carcinomas (13.5%), 4 adenoacanthomas (4.5%), and 2 clear cell adenocarcinomas (2%). Chest radiographs were retrospectively reviewed by two experienced readers. RESULTS: Lung metastases were found at the time of diagnosis of the primary tumor in 20 patients (22%). The usual pattern of PM involved multiple pulmonary nodules in 65 patients (72%); solitary pulmonary nodules were found in 16 (18%), mass lesion in 10 (11%), lymphangitic spread in 3, and pleural effusion in 6 (6.7%). Cavitation and tracheal metastasis were observed in one case each. CONCLUSION: Pulmonary metastases represent a common site of extrapelvic spread of disease for the small number of patients with advanced or recurrent endometrial carcinoma. The usual type of PM is multiple bilateral nodules.

Adult↗