The diagnosis of ventilator-associated pneumonia: a comparison of histologic, microbiologic, and clinical criteria

STUDY OBJECTIVE: To evaluate histologic, microbiological, and clinical criteria in the recognition of ventilator-associated pneumonia (VAP) in patients who died while mechanically ventilated. METHODS: The study group consisted of 39 patients who died after a mean of 14 days of mechanical ventilation. Postmortem fiberoptic bronchoscopy (FOB) and open lung biopsy were performed with collection of specimens initiated <1 h after death. The microbiological specimens included suction catheter aspirate of tracheal secretions, FOB-guided protected specimen brush (PSB) of tracheal secretions, blindly placed PSB in a distal airway, FOB-guided PSB in a distal airway, and FOB-guided BAL fluid (BALF) in a distal airway. Qualitative bacteriologic study was performed on all specimens, and quantitative bacteriologic study was performed on all but the suction catheter aspirate of the trachea. A biopsy specimen of peripheral lung parenchyma from the same region sampled by FOB was sent for quantitative culture and histologic analysis. The BALF was analyzed for cell population and percent of neutrophils containing intracellular organisms. The clinical criteria selected for comparison with histologic and microbiological results included a temperature > or =38.5 degrees C during the 48 h prior to death, a WBC count > or =15,000/mm3 in the 48 h prior to death, presence of a bacterial or fungal pathogen on the last sputum culture, radiographic worsening in the week prior to death, and worsening gas exchange defined as a 15% decrease in the PaO2/fraction of inspired oxygen ratio in the 72 h prior to death. RESULTS: None of the quantitative cultures had a reliable positive predictive value for histologic pneumonia. None of the five clinical criteria tested showed agreement with the presence or absence of histologic pneumonia. There was a significant correlation between qualitative and quantitative microbiological results from the distal airway/FOB-guided PSB, distal airway/BALF, and quantitative culture of the lung parenchyma. Also, suction catheter aspirate of the trachea had a sensitivity of 87% in recognizing the bacterial species simultaneously present in lung parenchyma. None of the patients with histologic pneumonia had <50% neutrophils in the BALF. CONCLUSIONS: Neither the bacterial, density from the four airway quantitative cultures, nor the bacterial density from quantitative culture of lung parenchyma accurately separated the histologic pneumonia and nonpneumonia groups. No clinical criteria or combination of clinical criteria correlated with the presence or absence of histologic pneumonia. A BALF with <50% neutrophils had a 100% negative predictive value for histologic pneumonia. A BALF quantitative culture had a sensitivity of 63%, specificity of 96%, and positive predictive value of 91% in recognizing sterile lung parenchyma. Thus, BALF may have a role in excluding pneumonia/infection in the ventilated patient. Antibiotic choice for the empiric therapy of VAP can be accurately guided by the microbial population recognized through culture of a tracheal suction catheter aspirate.     

Maintenance hemodialysis in IgD- lambda -type multiple myeloma associated with severe renal failure

Mechanically ventilated patients, especially those with thorax trauma, suffer commonly from nosocomial pneumonia. In these patients, conventional diagnostic criteria for bacterial pneumonia may not be completely reliable, as an accurate interpretation of the chest radiograph is too difficult. The invasive means for the diagnosis of pneumonia (protected specimen brush, bronchoalveolar lavage), require 24-48 hours to obtain the results of cultures. Therefore no information is available to guide the initial choice of antimicrobial therapy. For some authors, the quantification of intracellular bacteria, present in cytocentrifuged preparations made from lavage fluid, may provide rapid identification of patients with pneumonia. We evaluated the benefit of this type of analysis in thorax trauma patients. In 36 patients, 48 samples were taken. With a threshold value of 10% of cells containing intracellular organisms, microscopic examination had a sensitivity and a specificity of 83%. We conclude that this technique may be useful for the early diagnosis of nosocomial pneumonia in ventilated thorax trauma patients.     

Evaluation of sequential thallium and gallium scans of the chest in AIDS patients

With decreasing incidence of pneumocystis carinii pneumonia (PCP) in AIDS as a result of prophylactic regimens, there is a higher incidence of tuberculosis (TB), mycobacterium avii complex (MAC), kaposi sarcoma and malignant lymphoma. There is a need for differentiating these various pathological entities. The purpose of this study was for a retrospective evaluation of sequential thallium and gallium scans in AIDS patients for differentiating intrathoracic kaposi sarcoma from malignant lymphoma and opportunistic infections. METHODS: A total of 181 patients had both studies completed between March 1992 and May 1994. The final diagnosis was verified only in 83 patients. Results were correlated with the CD4 counts, bronchoscopic and chest radiograph findings. RESULTS: In patients with pulmonary kaposi sarcoma and no opportunistic infections (19 patients), a thallium-positive, gallium-negative pattern was detected in 17 patients with a sensitivity of 89%. In the presence of kaposi sarcoma plus opportunistic infections, this pattern was only detected in 7 of 19 patients (sensitivity dropped to 37%). In 45 patients with opportunistic infections and no kaposi sarcoma, only two false-positive findings were found in patients with cytomegalic virus pneumonia for a specificity of 96%. For the whole group of 83 patients, sensitivity was 63%; specificity 95%; positive predictive value 92%; accuracy 81%; and negative predictive value 75%. CONCLUSION: A thallium-positive, gallium-negative pattern in AIDS patients has a high specificity for the diagnosis of kaposi sarcoma, however, the sensitivity dropped from 89% to 37% in the presence of opportunistic infections.     

Intraoperative and postoperative use of mitomycin-C in the treatment of primary pterygium

OBJECTIVE: This study was conducted to determine the reliability of detecting features and making diagnoses of lower respiratory infections from chest radiograms in young infants. METHODS: Forty chest radiograms of infants younger than 6 months of age admitted with lower respiratory tract infection to a tertiary care pediatric hospital were independently reviewed on two separate occasions by three pediatric radiologists blinded to the patients' clinical diagnoses. For each radiograph the radiologists noted whether a feature was present, absent or equivocal on a standardized form. The features examined were hyperinflation, peribronchial thickening, perihilar linear opacities, atelectasis and consolidation. On the same form each radiologist indicated whether the radiograph was normal or showed airways and/or airspace disease. Within and between observer agreement were calculated by the average weighted kappa statistic. RESULTS: Within observer agreement for the radiologic features of hyperinflation, peribronchial wall thickening, perihilar linear opacities, atelectasis and consolidation were 0.85, 0.76, 0.87, 0.86 and 0.91, respectively. The between observer kappa results for these features were 0.83, 0.55, 0.82, 0.78 and 0.79, respectively. The within and between observer kappa statistics for interpretation of the radiographic features were best for airspace disease (within, 0.92; between, 0.91), and lower for normal (within, 0.80; between, 0.66) radiogram and for airways disease (within, 0.68; between, 0.48). The presence of consolidation was highly correlated with a diagnosis of airspace disease by all three radiologists. CONCLUSIONS: Clinicians basing the diagnosis of lower respiratory infections in young infants on radiographic diagnosis should be aware that there is variation in intraobserver and interobserver agreement among radiologists on the radiographic features used for diagnosis. There is also variation in how specific radiologic features are used in interpreting the radiogram. However, the cardial finding of consolidation for the diagnosis of pneumonia appears to be highly reliable.     

Accuracy of auscultation in the detection of haemopneumothorax

OBJECTIVE: To assess the accuracy of auscultation in the detection of haemopneumothorax. DESIGN: Prospective study. SETTING: University hospital, Taiwan. PATIENTS: 148 patients with chest injuries admitted between July 1994 and August 1996. MAIN OUTCOME MEASURES: Correlation between the results of auscultation and radiographic findings in 148 patients with injuries to the chest. 83 (56%) had internal injuries, of whom 38 had pneumothoraces, 24 haemothoraces, and 21 haemopneumothoraces. RESULTS: Auscultation had a sensitivity of 84%, a specificity of 97%, an accuracy of 89% and a positive predictive value of 97% in the detection of these injuries. CONCLUSIONS: Auscultation is not as accurate as chest radiography. Chest tubes can be inserted before chest radiography in patients in whom auscultation has indicated an injury. A chest radiograph is essential in those patients with normal breath sounds to exclude a haemopneumothorax that had been missed by auscultation.     

Regional cardiac sympathetic nerve dysfunction and the diagnostic efficacy of metaiodobenzylguanidine tomography in stable coronary artery disease

The present study endeavors to correlate regional myocardial sympathetic nerve dysfunction with reversible and persistent perfusion abnormalities and depressed regional wall motion, and to determine the diagnostic efficacy of radio-iodinated metaiodobenzylguanidine (MIBG) tomography for detecting coronary artery disease. In 28 consecutive patients with stable coronary artery disease and 7 patients with atypical chest pain but no coronary stenosis, regional MIBG uptake was semiquantitatively evaluated in 13 left ventricular segments early (30 minutes) and late (4 hours) after injection. Regional MIBG uptake was reduced in 68 of 90 segments (76%) showing reversible perfusion abnormality and 72 of 81 segments (89%) showing persistent abnormality 4 hours after injection. Although the sensitivity and negative predictive values of late MIBG scanning for detecting myocardial perfusion abnormalities were relatively high (82% and 85%, respectively), the specificity, positive predictive value, and kappa value were low (63%, 57%, and 0.41, respectively). Right coronary lesions were detected by late MIBG scanning with a high sensitivity (85%) but a low specificity (41%). Conversely, the sensitivities for detecting lesions in the other 2 major left coronary arteries were low (55%). The overall diagnostic accuracy of late MIBG scanning was 66% and the positive and negative predictive values and kappa value were low; 60%, 70%, and 0.31, respectively. Similarly, regional sympathetic dysfunction was observed in 42 of 49 asynergic segments (86%) on late MIBG scans, of which 32 segments were viable and 10 nonviable; but the low specificity (73%) and positive predictive value (44%) reduced the kappa value (0.43). Thus, regional cardiac sympathetic innervation is impaired in ischemic, asynergic but noninfarcted myocardium as well as in myocardium which is infarcted or has a persistent perfusion abnormality. The diagnostic efficacy of MIBG tomography to detect coronary artery disease, however, is limited probably because of nonspecific reductions of MIBG uptake in the inferior and posterolateral regions.     

An analysis of interleukin-8, interleukin-6 and C-reactive protein serum concentrations to predict fever, gram-negative bacteremia and complicated infection in neutropenic cancer patients

A prospective study was performed to assess the potential value of interleukin (IL)-8, IL-6, and C-reactive protein (CRP) serum levels to predict fever, gram-negative bacteremia and complicated infection in neutropenic patients with cancer. Serum samples were obtained three times a week during 208 neutropenic episodes following cytotoxic chemotherapy. Fever of any cause developed during 104 out of 191 evaluable episodes. Serum levels of neither cytokine nor CRP were predictive of fever within more than 24 h before its onset. Unlike CRP, both IL-6 and IL-8 serum levels were significantly different between microbiologically documented infections and unexplained fevers. The highest values of IL-6 and IL-8 were observed in episodes of gram-negative bacteremia. Using receiver-operating-characteristic curves, the analysis of cytokine levels measured around the onset of fever indicated that IL-8 is potentially useful for predicting gram-negative bacteremia, with a high negative predictive value of > 90% and a moderate positive predictive value of 50% (sensitivity, 70%; specificity, 91%). In patients with persistent fever, predictions of further clinical complications, defined as prolonged fever of more than 7 days' duration, pneumonia, shock and/or death due to infection, were best predicted by IL-6. With an IL-6 cutoff value of 250 pg/ml in samples obtained 8 to 32 h after onset of fever, the positive predictive value was 92%, the negative predictive value 91% (sensitivity, 85%; specificity, 95%). The positive predictive value of IL-6 in samples obtained another 24 h later from patients still febrile remained > 90%, but the negative predictive value dropped to 47%. In any of the analyses, the predictive values of CRP levels were poor and inferior to either cytokine. These findings may have clinical value in identifying subgroups of patients requiring different therapeutic approaches.     

Subcortical vascular dementia: survey of treatment patterns and research considerations

OBJECTIVE: The purpose of this study was to evaluate retrospectively the efficacy of a proposed panel of three cardiac markers (myoglobin, creatine kinase-MB mass [CK-MB], and cardiac troponin I) in the diagnosis of acute myocardial infarction (AMI) in patients with atraumatic chest pain. DESIGN: A total of 110 patients admitted for the evaluation of atraumatic chest pain were examined. Forty-one of these patients were diagnosed with AMI. RESULTS: Five of the 41 patients with AMI had abnormally elevated myoglobin levels, whereas values of CK-MB and/or cardiac troponin I remained negative. Creatine kinase-MB mass alone had a sensitivity of 92.7%, a specificity of 89.9%, a positive predictive value of 84.4%, and a negative predictive value of 95.0% for the diagnosis of AMI. Cardiac troponin I alone had a sensitivity of 90.2%, a specificity of 95.7%, a positive predictive value of 92.5%, and a negative predictive value of 94.3% for the diagnosis of AMI. Cardiac troponin I is a more specific marker for the diagnosis of AMI than CK-MB, particularly in patients with chronic renal failure who are evaluated for chest pain. The combination of CK-MB and cardiac troponin I increased the sensitivity to 100% and the negative predictive value to 100% and had a specificity of 88.4% and a positive predictive value of 83.7%. The panel was diagnostic for all patients with AMI within 12 hours after admission. CONCLUSIONS: Our preliminary results indicate that this panel is highly effective for evaluation of AMI in patients with atraumatic chest pain. Elevated myoglobin levels were useful in detecting patients at high risk for AMI who initially were not detected with other markers. The combination of CK-MB and cardiac troponin I provided much higher sensitivity and had a much higher negative predictive value for the evaluation of AMI than cardiac troponin I or CK-MB alone. The 100% negative predictive value is particularly important because it indicates that patients with negative CK-MB and cardiac troponin I values 12 hours after admission have a negligible likelihood of AMI.     

Autonomous cell death of mouse male germ cells during fetal and postnatal period

OBJECTIVE: To determine the utility of CT-determined main pulmonary artery diameter (MPAD) for predicting pulmonary hypertension (PH) in patients with parenchymal lung disease. DESIGN: Retrospective review of right-heart hemodynamic data and chest CT scans in 45 patients. SETTING: Tertiary-referral teaching hospital and VA hospital. PATIENTS: Between October 1990 and December 1995, 36 patients referred for evaluation of parenchymal lung disease or possible pulmonary vascular disease were found to have PH, as defined by mean pulmonary artery pressure (mPAP) > or =20 mm Hg. Nine control patients (mPAP <20 mm Hg) were also identified (4 from hospital records search, 5 after evaluation for possible PH). RESULTS: CT-determined MPAD was 35+/-6 mm in patients with PH and 27+/-2 mm in control subjects. In our group of patients, MPAD > or =29 mm had a sensitivity of 87%, specificity of 89%, positive predictive value (PPV) of 0.97, and positive likelihood ratio (LR) of 7.91 for predicting PH; in the subgroup of patients with parenchymal lung disease (n=28, PH and control subjects), MPAD > or =29 mm had a sensitivity of 84%, specificity of 75%, PPV of 0.95, and positive LR of 3.36 for predicting PH. The most specific findings for the presence of PH were both MPAD > or =29 mm and segmental artery-to-bronchus ratio > 1:1 in three or four lobes (specificity, 100%). There was no linear correlation between the degree of PH and MPAD (r=0.124). CONCLUSIONS: CT-determined MPAD has excellent diagnostic value for detection of PH in patients with advanced lung disease. Therefore, standard chest CT scans can be used to screen for PH as a cause of exertional limitation in patients with parenchymal lung disease. Because CT is commonly used to evaluate parenchymal lung disease, this information is readily available.     

A new bronchoscopic technique for the diagnosis of bacterial pneumonia in HIV-positive patients

The aim of the present study was to evaluate in HIV-positive patients with bacterial pneumonia, the diagnostic value of a new endoscopic technique that uses a single catheter to perform a telescopic plugged catheter (TPC) followed by a modified protected bronchoalveolar lavage (mpBAL). Fifty-eight HIV-positive patients with respiratory infection were included in the study. Samples from TPC and mpBAL were cultured quantitatively. Standard bronchoalveolar lavage was performed to rule out opportunistic infections. According to the clinical and microbiological results, patients were classified in the study group (27 with bacterial pneumonia) or the control group (31 without bacterial pneumonia). Sensitivity of TPC was 56% [95% confidence intervals (CI) 37-75%] and its specificity was 100%; these figures were 56% (CI, 37-75%) and 94% (CI, 86-100%) for mpBAL. When both techniques were assessed together, sensitivity increased to 70% (CI, 53-87%). The use of a single catheter reduced the cost of the originally described pBAL procedure by approximately 50%. The use of a single catheter to perform a TPC followed by a mpBAL can improve the diagnostic yield in HIV-positive patients with bacterial pneumonia, and reduces its cost.     

Early diagnosis of ventilator-associated pneumonia. Is it possible to define a cutoff value of infected cells in BAL fluid?

STUDY OBJECTIVE: To assess the usefulness of quantification of infected cells (ICs) in BAL fluid for the diagnosis of ventilator-associated pneumonia (VAP). DESIGN: A prospective study. SETTING: A medico-surgical ICU in a tertiary health-care institution. PATIENTS: One hundred thirty-two patients (mean age, 52 +/- 19 years). The suspicion of nosocomial pneumonia was strong in these patients: all had fever (> or = 38.5 degrees C), purulent tracheal aspirates, leukocytosis (> or = 10,000 cells per cubic millimeter), and new or persistent radiographic lung infiltrates. INTERVENTIONS: One hundred sixty-three samples (BAL and protected specimen brushes [PSB]) were obtained. RESULTS: VAP was present in 56 cases. The diagnosis was excluded in the remaining 107 cases. The IC count was performed on 100 cells in BAL fluid. The percentage of IC was significantly higher (12.6 +/- 12.4 vs 1.14 +/- 3.39; p < 0.0001) in patients with pneumonia: the area under the receiver operating characteristic (ROC) curve was 0.888 and a threshold of 2% of IC corresponded to a sensitivity of 84%, a specificity of 80%, a positive predictive value of 69%, and a negative predictive value of 90%. CONCLUSIONS: It is possible to define a threshold of IC in BAL fluid with a good reliability by using an ROC curve. This technique is useful for the early diagnosis (< 2 h) of nosocomial bacterial pneumonia in mechanically ventilated patients and allows a rapid and appropriate treatment of most of the patients with suspected VAP.     

Relationship between abnormalities on high-resolution CT and pulmonary function in systemic sclerosis

STUDY OBJECTIVES: To determine the predictive value of abnormalities on high-resolution CT (HRCT) on pulmonary disease in systemic sclerosis. PATIENTS: Fifty-two patients suffering from systemic sclerosis. DESIGN: Pulmonary disease was defined by pulmonary function test abnormalities, ie, total lung capacity (TLC) <80% of predicted value and/or diffusion of carbon monoxide (DLCO) <75% of predicted value, without any pulmonary event other than systemic sclerosis in the medical history. Patients were divided in two groups, group A with pulmonary disease (29 patients) and group B without pulmonary disease (23 patients). HRCT abnormalities were scored on whole lungs. A decision matrix was constructed to determine sensitivity, specificity, positive and negative predictive values, and false-positive and false-negative rates. A receiver operating characteristic curve was constructed to determine the best compromise between sensitivity and specificity. RESULTS: HRCT total scores were higher in group A (9.0+/-4.3) than in group B (5.0+/-2.8) (p < 0.001) and they correlated with TLC (r =-0.39, p < 0.005) and DLCO (r = -0.50, p < 0.0002). An HRCT score of 7 corresponded to the best compromise between sensitivity (0.60) and specificity (0.83), with a positive predictive value of 0.82. Taking into account a value of 10 for the HRCT score increased specificity to 1 but decreased sensitivity to 0.41. CONCLUSION: A minimum score of 7 would be required to consider HRCT abnormalities in systemic sclerosis as predictive of pulmonary disease. An HRCT score of 10 makes it possible to establish the diagnosis of lung involvement severe enough to impair pulmonary function.     

Granulomatous hypophysitis caused by a ruptured intrasellar Rathke''s cleft cyst: report of a case and review of the literature

STUDY OBJECTIVES: To determine the clinical significance of Candida sp isolated from bronchoscopic samples in patients with suspected pneumonia. DESIGN: A retrospective chart review was performed in all nonneutropenic adult patients with Candida sp isolates from respiratory secretions obtained by bronchoscopy over a 5-year period (1991 to 1995). Potential risk factors, therapeutic decisions, and outcome were recorded. Microbiological findings, chest radiograph reports, and pathologic material were reviewed. Isolates were classified as definite, probable, or indeterminate contamination, or as definite pulmonary candidiasis, on the basis of histologic findings, therapeutic decisions, and outcome. SETTING: A 600-bed teaching hospital with 16 beds in a medical-surgical ICU. PATIENTS: Thirty-seven consecutive patients with positive cultures for Candida sp from respiratory samples obtained by bronchoscopy were evaluated. Thirty-two of these 37 patients (86.5%) received antibiotic therapy prior to sampling, and 23 (62.2%) were intubated. RESULTS: Contamination was classified as definite in 3 patients (8.1%) and probable in 30 others (81.0%). Contamination was indeterminate in two cases (5.4%). Two additional patients (5.4%) received antifungal agents for systemic candidiasis. No cases of pulmonary candidiasis could be demonstrated, although 24 of 28 patients showed protected specimen brush cultures > or = 10(3) cfu/mL. CONCLUSIONS: Nonneutropenic patients with isolation of Candida sp from bronchoscopic samples, even in high concentrations, are unlikely to have invasive candidiasis. Indication for initiation of antifungal therapy should be based on histologic evidence or identification from sterile specimens.     

Homeless children

The aim of the study was to evaluate the applicability to urine samples of the Amplified Mycobacterium tuberculosis Direct Detection Test (AMTD), which is currently used to identify this organism in respiratory specimens within a few hours. The study was performed on 95 patients, comprising 35 subjects with a high index of suspicion for active tuberculosis of the urinary tract and 60 subjects with evidence of non-mycobacterial disease. One urine specimen from each subject was examined by microscopy, culture and AMTD. AMTD was positive in 38 specimens and negative in 57. Assuming culture as the reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 91.93%, 86.84% and 100%, respectively. Reassessing the discrepancies between AMTD and culture by review of patients' charts, the sensitivity, specificity, positive predictive value and negative predictive value of AMTD were 100%, 93.44%, 89.47% and 100%. The results of the study as well as the characteristics of AMTD encourage its use for the rapid recognition of urinary tract tuberculosis, although its findings should be interpreted cautiously when the clinical picture is not consistent with an active tuberculosis.     

Evaluation of a new urease reagent strip for detection of Helicobacter pylori in gastric biopsy specimens

OBJECTIVES: Determine sensitivity and specificity of a new urease reagent strip (URS) test for detection of Helicobacter pylori in gastric biopsy specimens. METHODS: Six paired biopsy specimens were obtained from the greater curvature of the distal antrum, the lesser curvature near the incisura, and the corpus along the greater curvature during 66 procedures on 59 patients with endoscopic findings of gastric antral mucosal erythema or erosions, or gastric or duodenal ulcers. One biopsy from each site was tested with the URS. The second was evaluated with histology. A final antral biopsy was evaluated with a urea/gel test. RESULTS: Twenty-eight of the 66 cases were histologically positive, with H. pylori observed in at least one of the three biopsy sites. The URS test correctly identified all 28. Of 193 individual biopsy specimens, 78 were positive for H. pylori. The URS correctly identified 77. Sensitivity was 0.99, specificity 0.95, positive predictive value 0.93, negative predictive value 0.99, and kappa 0.92. Average time to positive was 20 min. Twenty-seven antral biopsies were histologically positive for H. pylori. The URS test correctly identified all 27, whereas the urea/gel test correctly identified 21. For antral sites, URS sensitivity was 1.00 and specificity 0.95 versus urea/gel test sensitivity of 0.75 and specificity of 1.00. CONCLUSIONS: In this sample, the URS test is as accurate as histology in diagnosing H. pylori infections, and it provides results in less time and at a lower cost than histology.     

Luminol-enhanced, whole blood chemiluminescence of human neutrophils evaluated by means of an automated, computer-assisted, and high-sensitivity luminescence analyzer

To evaluate the usefulness of two standardized commercially available amplification assays for the detection of Mycobacterium tuberculosis: Amplicor test (Roche) and MTD-Amplified direct test (Gen-Probe) a total of 281 respiratory specimens from 198 patients with symptoms of pulmonary diseases were examined and compared with conventional methods. Fifty-seven specimens were positive and 218 negative by both amplification assays. Three specimens were reactive by Amplicor only, and three by MTD only. In comparison with culture, the sensitivity, specificity, positive predictive value and negative predictive value were 96.0, 94.8, 80.0, and 99.1%, respectively, for the Amplicor test; the corresponding values were 94.0, 94.4, 78.3, and 98.6%, respectively, for the MTD. However, when 28 specimens from 14 patients on antituberculous therapy were excluded the improvement in PPV and specificity of both assays was obtained. In conclusion, both commercially available amplification tests are almost equally sensitive and specific and are suitable for the implementation in daily routine work in the specialized clinical laboratories.     

The role of transvaginal ultrasonography and outpatient diagnostic hysteroscopy in the evaluation of patients with menorrhagia

To verify the reliability of transvaginal ultrasonography in diagnosing intrauterine disease and in evaluating the operability of submucous myomas and to determine the feasibility, acceptability and validity of hysteroscopy for menorrhagia, we performed a prospective 5 year study on 793 women of mean age +/- SD of 41.5 +/- 7.8 years. All the patients referred for excessive menstrual bleeding with uterine volume <12 week pregnancy who underwent complete physical examination, transvaginal ultrasonography and outpatient hysteroscopy with endometrial biopsy were included in the study. Outpatient hysteroscopy was not completed due to intolerance or was unsatisfactory due to excessive bleeding in 23 cases (2.9%). Only 28 women (3.5%) declared they would have refused the procedure had they imagined the pain involved. One case of pelvic infection was observed. Compared with hysteroscopy, transvaginal ultrasonography had 96% sensitivity, 86% specificity, 91% positive predictive value and 94% negative predictive value in the diagnosis of intrauterine abnormality. The sensitivity, specificity, positive and negative predictive values of ultrasonography in identifying submucous myomas operable hysteroscopically (intramural extension <50%) were respectively 80, 69, 83 and 65% with a k index of agreement between ultrasonography and hysteroscopy of 0.48. Thus, considering the good specificity and high negative predictive value, transvaginal ultrasonography may be suggested as the initial investigation in menorrhagic patients, limiting hysteroscopy to cases with positive or doubtful sonographic findings.     

Involvement of dental occlusion and trigeminal neuralgia: a clinical report

Over a 12-month period 501 children (age range 11 months to 15 years) underwent surgery for a possible middle ear effusion. All had tympanometry performed within 2 h of surgery. The results of tympanometry were correlated with the surgical findings in 955 ears. A type-B tympanogram has a high sensitivity (0.91) in predicting middle ear effusion with good specificity (0.79). A type-A tympanogram has a very high specificity (0.99) in predicting a dry middle ear but low sensitivity (0.34). Both the positive (0.91) and negative (0.84) predictive values of a type-A tympanogram are high. The addition of a type-C tympanogram increases the sensitivity of predicting a dry middle ear to 0.79. The positive predictive value of a peaked (type-A or -C) tympanogram is 0.71 and should be considered strong evidence that the middle ear is dry. Tympanometry is the best clinical test for the presence or absence of a middle ear effusion, and on the basis of preoperative tympanometry alone the need for surgery should be carefully reassessed.     

Rapid diagnosis of tuberculosis using the amplification method

BACKGROUND: Amplification methods identify Microbacterium tuberculosis on the basis of genus- or species-specific sequence of bases in nucleic acids which they replete exponentially. The objective of the work was comparison of results of biological samples by the method Gen-Probe Mycobacterium tuberculosis Direct Test (MTD) using amplification of ribosomal RNA and BK by microscopy and cultivation, assessment of standard indicators of their efficiency of the method and analysis of diverging results. METHODS AND RESULTS: During the period between April 19, 1994 and October 19, 1995 a total of 650 specimens from 316 patients examined for suspected tuberculosis were processed. After decontamination the specimens were divided into two portions and examined by the Gen-Probe MTD and by classical BK microscopy and cultivation. 95 specimens were Gen-Probe MTD positive. As compared with BK cultivation the sensitivity of Gen-Probe MTD is 94.7%, the specificity 93.1%, the positive predictive value 56.8% and the negative predictive value 99.5%. Falsely positive were the specimens from 33 patients, most frequently with a diagnosis of tumours, non-specific bronchopneumonias and interstitial pulmonary fibroses. CONCLUSIONS: Gen-Probe MTD is a rapid examination with an equal or higher sensitivity than BK cultivation. The disadvantage is a somewhat lower specificity and higher cost.     

Usefulness of angiotensin converting enzyme inhibitors in the diagnosis of renovascular hypertension. III. Evaluation of the validity of the captopril test and the reno-scintigraphic captopril test in the diagnosis of renovascular hypertension according to accepted criteria

The aim of the study was to evaluate diagnostic validity of captopril test and scintigraphic test before and after captopril for the detection of renovascular hypertension (RVH) according to applied criteria. Employing blood pressure response to captopril as a criteria sensitivity was 37.0%, specificity 92.1%, positive predictive value 75.0% and negative predictive value 70.2% in the captopril test. Applying plasma renin activity (PRA) response to captopril as a criteria sensitivity was 92.5%, specificity 100%, positive predictive value 100% and negative predictive value 96.0% in the same test. Renin captopril test has excellent sensitivity and positive predictive value, is easy to perform and inexpensive and therefore may be a useful screening test for RVH in unselected population. With the own criteria used, captopril renoscintigraphy detected RVH with 87.5% sensitivity, 91.7% specificity, 87.5% positive predictive value and 91.7% negative predictive value. Captopril renoscintigraphy is an accurate diagnostic test for the identification of RVH in a clinically selected high-risk population. Common evaluation of both tests does not improve their accuracy in diagnosis of RVH.