Clinical utility of the polymerase chain reaction in the diagnosis of extrapulmonary tuberculosis

This study examines the diagnostic utility of the polymerase chain reaction (PCR) in 156 patients (five human immunodeficiency virus (HIV) seropositive) suspected of extrapulmonary tuberculosis. The results of PCR in 226 samples from 11 different sites were compared with the results of microscopy and culture. Positive culture results were predicted in 86% of samples by PCR but in only 31% by microscopy. Specificity of PCR was 92%. In cases with culture-proven tuberculosis, PCR identified all 11 microscopy positive cases and 19 of 24 (79%) of the microscopy-negative cases. In four patients, PCR excluded the diagnosis of tuberculosis in microscopy-positive samples, which were later shown to contain mycobacteria other than Mycobacterium tuberculosis or laboratory contaminants. In 20 patients (microscopy, PCR and culture negative) a trial of antituberculous drugs was given, but patients showed no improvement and treatment was stopped. In 17 patients, all culture negative (in nine PCR was positive, three of whom also had positive microscopy) the diagnosis was probable tuberculosis based on clinical findings and response to treatment. This polymerase chain reaction has a much higher sensitivity than microscopy and can facilitate therapeutic decisions for those with suspected extrapulmonary tuberculosis.     

Coexisting extrapulmonary tuberculosis and malignancy

Electron paramagnetic resonance spectroscopy (EPR) was used to study synthetic hydroxyapatite and approximately 1, 2, and 6% synthetic carbonated apatites, deorganified dentine, and enamel. The carbonated apatites were synthesized by hydrolysis of dicalcium phosphate. Comparisons were made with spectra from enamel and deorganified dentine. Microwave power saturation and dose responses were determined for the synthetic materials. The Marquardt version of the Levenberg decomposition method was used to extract individual signals from the apatite data. Two samples of dentine were irradiated with 25 and 100 Gy, respectively, from a 60Co source. The first sample was then deorganified at 200 degreesC using the Soxhlet extraction technique. A third sample was irradiated with 100 Gy after deorganification. The resulting EPR spectra were then compared. It was determined that the dosimetric signal of 2% synthetic carbonated apatite was approximately the same as that of enamel. It was also verified that the dosimetric signal saturates at about 2% in synthetic carbonated apatites. The study established that the precenters responsible for the dosimetric signal (g perpendicular = 2.0018, g parallel = 1.9985) are preferentially concentrated in the surface-accessible region of the mineral component, as shown by the approximately 80% attenuation of the dosimetric signal in dentine following deorganification. The precenters responsible are not destroyed by the deorganification since the magnitude of the dosimetric signal from the dentine specimen irradiated following deorganification was approximately twice that of the comparable untreated, irradiated sample. Finally, the dose response of 2 and 6% synthetic carbonated apatites was determined.     

Differential diagnosis of pulmonary tuberculosis

Differential diagnosis of pulmonary tuberculosis is discussed. Chest X-ray findings of pulmonary tuberculosis may be greatly varied, because tuberculosis may cause three different lesions: an exudative lesion, a proliferative lesion, and a fibrotic lesion, and because it may invade all the structure. Thus, the differential diagnosis of pulmonary tuberculosis includes very many diseases. The most important differential diagnosis of nodule is tuberculoma and lung cancer. The clue of the diagnosis is the feature of the nodule and surrounding structure, such as pleural indentation, or knotching. There is, however, the limitation of the diagnosis by imaging: some tuberculoma may show the identical feature with the pulmonary adenocarcinoma. It is important to gather the pathological or bacteriological evidences by means of suitable procedures.     

Current problems of extrapulmonary tuberculosis

The small intestine vagotomy influence on gastric secretion function, stimulated by pentagastrin and carbachol, was investigated while chronic experiment on dogs with gastric fundal and duodenal fistulas. The comparative analysis of influence of extragastric selective proximal, selective distal, selective and truncal vagotomy on gastric secretion in various terms after operative intervention was also conducted. In 6 months after conduction of various kinds of vagotomy the reduction of hydrochloric acid secretion, stimulated by pentagastrin, was noted.     

Serodiagnosis of extrapulmonary tuberculosis by ELISA

This study aims at evaluating the specificity and sensitivity of ELISA test in detection of Mycobacterial Antibodies using A60 antigen. Sera from 100 clinically suspected cases of extrapulmonary tuberculosis were studied along with 10 sputum positive cases 25 age and sex matched healthy control. Overall positivity of the test was 80.00 per cent with 100 percent sensitivity and 92 per cent specificity. The present study recommends ELISA as an adjunct to other investigative procedures.     

Imaging approach to the diagnosis of pulmonary sequestration

PURPOSE: To describe the characteristic features of pulmonary sequestration (PS), to evaluate the usefulness of various imaging modalities, and to find a rational approach to accurate diagnosis. MATERIAL AND METHODS: Twenty-four patients with PS proved by operation and pathology were reviewed retrospectively. Plain chest films were done in all patients, bronchography in 3, sonography in 14, CT in 6 (including CT angiography in 1 case), MR in 8 (including MR angiography in 1 case) and aortography in 12 (including DSA in 1 case). RESULTS: Plain chest films demonstrated a solid mass in 14 patients and a cystic mass in 10. Bronchograms showed displacement of adjacent bronchi with no filling of contrast medium within the lesion in 2 cases, while another case had a blind intermediate portion of the right bronchus (hypoplasia of middle and lower lobes associated with extralobar sequestration). Sonography demonstrated a solid lung mass in 12 cases and a solid mass with cystic areas in 2, and detected vessel-like structures within the mass or in its surroundings in 12. Doppler analysis showed arterial spectral wave confirming a feeding artery. CT revealed a solid mass in all patients, a mass with low density area in 4, and emphysema surrounding the mass in 3. MR imaging depicted anomalous arteries in all patients and venous drainage in 4 cases. Aortography demonstrated anomalous systemic arterial supply to the PS in all patients. In this series, 21 cases (87.5%) were correctly diagnosed preoperatively by the imaging modalities. CONCLUSION: Plain chest films can provide a diagnostic clue to PS. Sonography, CT and MR are helpful for showing arterial blood supply and for making a definite diagnosis. We recommend a rational imaging approach for the diagnosis of PS.     

Current concept in the diagnosis and treatment of childhood pulmonary tuberculosis

In India, an estimated 80% of children are infected with tubercle bacillus by 10 years of age. Elimination of tuberculosis depends on finding all infectious patients and providing them with curative chemotherapy. Pulmonary tuberculosis--the most common form in children--is diagnosed when a child presents with fever, prolonged cough, weight loss, recurrent wheezing, or chest infection; the chest x-ray is suggestive of tuberculosis; and three or more of the following conditions exist: 1) Mantoux test result of 10 mm or more, 2) tuberculosis lymphadenitis by fine needle aspiration cytology, 3) grade III malnutrition, 4) no BCG vaccination, 5) positive family history of tuberculosis, and 6) recent history of pertussis or measles. Recommended, for children with pulmonary tuberculosis, is a regimen of isoniazid, rifampicin, and pyrazinamide daily for 2 months, followed by the first two drugs daily for an additional 4 months. The poor tuberculosis cure rates in most developing countries reflect patient non-compliance with treatment regimens.     

Slide agglutination test for the diagnosis of pulmonary and extra-pulmonary tuberculosis

Nasal polyposis can be defined as a chronic inflammatory disease of the paranasal sinus mucosa, leading to a protrusion of benign edematous polyps from the meatus into the nasal cavities. Nasal polyps are histologically characterized by massive edema and accumulation of eosinophils. IgE-mediated allergy seems to play only a minor role in eosinophil accumulation, leaving the place for a new concept of non-allergic rhinitis with eosinophilia. The central question still remains, however, why eosinophils accumulate into nasal polyposis tissue. Some initial data show that tissue structural cells, i.e. epithelial cells or fibroblasts, could produce cytokines (GM-CSF) and play a role in eosinophil accumulation (micro-environmental theory). However, further studies showed, that GM-CSF was mainly produced by eosinophils themselves (autocrine theory), leading to the hypothesis of an intrinsic eosinophilic inflammatory process. Eosinophils may contribute to nasal polyp formation and growth not only through inflammation but also by exerting their effects on extracellular matrix including stimulation of collagen synthesis. Another feature associated with nasal polyposis is aspirin sensitivity. Some preliminary data indicate that eosinophils could also be involved in aspirin-sensitivity mechanisms.     

Clinical efficacy of the amplified Mycobacterium tuberculosis direct test for the diagnosis of pulmonary tuberculosis

The amplified Mycobacterium tuberculosis direct test (MTD) is a rapid diagnostic test based on a nucleic acid amplification technique, which can be used directly on processed clinical specimens. We evaluated the clinical utility of the MTD for diagnosing pulmonary tuberculosis by comparing the sensitivity and specificity of the test with acid-fast smear, mycobacterial culture, and clinical evaluation. The study included 844 respiratory tract specimens from 421 patients, which were submitted to the microbiology laboratory of our urban teaching hospital over a 6-mo period. Compared with culture, MTD had a sensitivity of 93.6% and specificity of 97.8%. MTD was more sensitive in detecting pulmonary tuberculosis in patients with previously undiagnosed disease (74.7%) than in those with established disease receiving chemotherapy (29.2%), and in smear-positive (95.5%) than in smear-negative (70.0%) disease. There were two false positive MTD results in patients with nontuberculous mycobacteria, for a specificity in this population of 97.3%. We conclude that MTD, when used in conjunction with routine smear and culture, is a useful rapid diagnostic test for suspected pulmonary tuberculosis.     

Value of examining multiple sputum specimens in the diagnosis of pulmonary tuberculosis

To objectively assess the value of examining multiple sputum specimens in maximizing the sensitivity of detection of Mycobacterium tuberculosis, we retrospectively reviewed the acid-fast bacillus smear and culture results of patients diagnosed with culture-proven pulmonary tuberculosis (TB) at Hennepin County Medical Center between 1986 and 1996. Two hundred and forty six persons were diagnosed with pulmonary TB in the time period analyzed. In 93% of these cases (229 of 246) the laboratory diagnosis was made by detection of M. tuberculosis in sputum specimens; however, only 52% (120 of 229) of these patients had at least three sputum specimens submitted to the laboratory at the time of diagnosis. Of the patients from whom at least three specimens were collected, 47% (56 of 120) had at least one smear-positive specimen; the third or later specimen submitted was the first smear-positive specimen for 13% (7 of 56) of these persons but was the first culture-positive specimen for only 7% (4 of 56). Of the 64 patients with smear-negative specimens, for only 5% (3 of 64) was the third or subsequent specimen submitted the first from which M. tuberculosis was recovered. This data indicates that, in our institution, the overwhelming majority of culture-proven pulmonary TB cases are diagnosed from the first or second sputum specimen submitted to the laboratory and that only rarely is a third specimen of diagnostic value.     

Epidemiology of extrapulmonary tuberculosis among persons with AIDS in the United States

We compared the antihypertensive efficacy of once-daily amlodipine (AM) versus nitrendipine (NTR) by 24-h ambulatory blood pressure monitoring (24-h ABPM) in 32 patients with mild to moderate essential hypertension (EH). After a 2-week single-blind, placebo run-in period, patients were randomized in a double-blind, parallel fashion: 14 received AM 5 mg and 18 NTR 10 mg. After 2 weeks, dose was adjusted if necessary (AM 10 mg or NTR 20 mg) and continued for another 6-week period. At the end of the placebo period and during the last week of treatment, patients underwent 24-h ABPM. Initial office BP mean values were similar in both groups (169.8 +/- 14/102.5 +/- 6 vs. 167.1 +/- 14/98.7 +/- 5 mm Hg, respectively, p = NS). A comparable decrease in office mean values of systolic BP (SBP, -22.3 +/- 13 vs. -19.1 +/- 16 mm Hg) and diastolic BP (DBP, -12.0 +/- 5 vs. -8.1 +/- 8 mm Hg) was observed. Nevertheless, 24-h ABPM mean values differed significantly between patients treated with AM or NTR with regard to 24-h SBP (120.0 +/- 10 vs. 132.5 +/- 1 mm Hg, p = 0.01). Moreover, the average decrease in 24-h SBP (-19.3 +/- 6 vs. -5.2 +/- 11 mm Hg, p = 0.0036) and 24-h DBP (-10.7 +/- 4 vs. -3.7 +/- 6 mm Hg, p = 0.0047) was higher in the AM group, with no changes in 24-h heart rate (HR). At equivalent once-daily dosage, AM was more effective than NTR in decreasing BP assessed by 24-h ABPM.     

Postural reactions of the circulatory system in patients with extrapulmonary tuberculosis]

The main cause of occurrence of postural reactions in patients with extrapulmonary tuberculosis is a deficit of blood circulatory volume as well as cerebrospinal disturbances and "harmful" peculiarities of the operative posture. An increase of the circulatory volume by infusion of 0.5-1.0 litres of plasma substituting substances prior to patient's being rendered the operative posture liquidates, to a great extent, postural reactions of the circulatory system.     

Limits of commercial molecular tests for diagnosis of pulmonary tuberculosis

Several studies report high specificity, but variable sensitivity, of Amplified Mycobacterium tuberculosis Direct Test (AMTDT, Gen-Probe) based on ribosomal ribonucleic acid (rRNA) amplification and Amplicor Mycobacterium tuberculosis test (Amplicor, Roche) based on deoxyribonucleic acid (DNA) amplification for diagnosis of pulmonary tuberculosis. We have retrospectively evaluated these assays on selected acid-fast bacilli (AFB)-positive and -negative smear specimens and compared the results obtained from nucleic acid amplification with those of AFB staining of semi-quantitative cultures as determined by radiometric Bactec and L?wenstein-Jensen cultures. In comparison to cultures, Amplicor and AMTDT assays exhibited identical overall sensitivities of 80%, while the staining had a lower sensitivity of 62%. The sensitivities of Amplicor and AMTDT were 98% and 100%, respectively, for the AFB-positive specimens, and 50 and 46%, respectively for the AFB-negative specimens in comparison to cultures. The sensitivities of both assays appeared similar, and were directly related to the number of bacilli in the specimens studied. The low sensitivity (50%) for smear-negative specimens showed that current amplification assays may be unsuitable to replace cultures for diagnosis of tuberculosis. The decision to perform these molecular techniques should result from close co-operation between clinicians and microbiologists, taking into account the sensitivity results reported here, as well as the expense of the assays.     

A study on the relapse and its potential causes in pulmonary tuberculosis

A retrospective cohort study was conducted to acquire the general picture of relapse in pulmonary tuberculosis in China and to clarify the relationship between potential causes and relapse rate. All data were collected from 4,797 initial sputum-positive cases. Results showed: (1) Bacteriological relapse rate within two years after chemotherapy was 4.6%. (2) Cumulative relapse rates within half a year and a year only accounted for respectively 28% and 43% of that within two years after chemotherapy. (3) Patients over 60 years old, with drug-resistant bacilli, with long excretion of bacilli, or with residual cavity(ies) or bacterial-negative conversion of less than 3 months at the end of treatment, were the high risk population of relapse.     

Significance of prosectorship and autopsies archives in the study of pulmonary tuberculosis pathology

The study revealed the pathomorphology of pulmonary tuberculosis by using abundant retrospective materials from the prosectorship's archives (1061 autopsies), which referred to individuals who had died from pulmonary tuberculosis in the pretreatment and treatment periods. The comparative analysis of autopsies in the populational context is an important method of this new medical line of pathoanatomical investigations.