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Diagnostic method for differentiating external hydrocephalus from simple subdural hygroma.

OBJECT: The various terms used to describe subdural fluid collection--"external hydrocephalus", "subdural hygroma", "subdural effusion", "benign subdural collection", and "extraventricular obstructive hydrocephalus"-reflect the confusion surrounding the diagnoses of these diseases. Differentiating external hydrocephalus from simple subdural hygroma may be difficult, but the former appears to be a distinct clinical entity separate from the latter. In this report, the authors present a diagnostic method for differentiating external hydrocephalus from simple subdural hygroma, based on their clinical experience in treating subdural fluid collection after mild head trauma. METHODS: Twenty patients with subdural fluid collection after mild head trauma were included in this study. Ventricle size was measured using a modified frontal horn index (mFHI); that is, the largest width of the frontal horns divided by the bicortical distance in the same plane, instead of the inner table distance. Bur hole trephination was performed on the appearance of a subdural fluid collection thicker than 15 mm on computed tomography (CT), persistent (longer than 4 weeks) or increasing in size, and accompanied by neurological symptoms (confusion or memory impairment). During the procedure, subdural pressure was measured using a manometer before opening the dura mater. Subdural pressure varied among the patients, ranging from 3 to 27.5 cm H2O. Four patients with a subdural pressure greater than 15 cm H2O had hydrocephalus after surgery (p < 0.05). Hydrocephalus developed in a pediatric patient (2 years old) with a subdural pressure of 12 cm H2O. All of the patients in whom hydrocephalus developed after bur hole trephination had had enlarged ventricles (mFHI > 33%) on preoperative CT scans. CONCLUSIONS: Monitoring subdural pressure may be a valuable tool for differentiating subdural hygroma from external hydrocephalus in patients with mild head trauma. Additionally, the mFHI reflects the nature of the subdural collection more accurately than the standard frontal horn index.

Adolescent↗

[Diagnostic methods of central nervous system changes in SLE patients].

Systemic lupus erythematosus is an autoimmune, multiorgan disease, in the course of which central nervous system (CNS) disturbances are usually observed. Pathomechanism of CNS changes is complex and not fully investigated. Neuropathological alterations are often not characteristic, usually caused by vasculopathy, infarction, hemorrhages or infection. Vascular changes are generally disseminated and develop in different time period, sometimes they precede clinical symptoms. Currently applied diagnostic methods and their usefulness in diagnosis of CNS involvement in lupus patients, especially single photon emission computed tomography (SPECT), are presented.

Brain↗

[Bronchial hyperreactivity. II. Diagnostic methods].

Bronchial hyperreactivity is studied for the evaluation of airways' response to stimuli that provoke bronchoconstriction in hyperreactive subjects. Exercise is often used, especially in children. This method in simple, sufficiently tolerated and reproducible. The inhalation of ultrasonically-nebulized distilled water is a simple, reproducible and rapid to perform in the majority of adult patients test; in childhood it is poorly inquired. Pharmacological tests (with histamine or methacholine) have a greater sensitivity and reproducibility. Aspecific bronchoprovocation with methacholine is a diagnostic method that allows the diagnosis of bronchial hyperreactivity in asymptomatic subjects with asthma, recurrent cough and recurrent bronchopneumonia.

Adrenergic beta-Antagonists↗

[Obstructive defecation. Diagnostic methods and treatment].

Obstructive defecation is observed in approximately half of all patients with functional constipation. Functional constipation has been related to alterations in intestinal motility (slow transit constipation) and to pelvic floor disorders leading to obstructive defecation associated with anatomical alterations of the pelvic floor (rectocele, posterior perineal hernia, enterocele and sigmoidocele, internal rectal intussusception, occult mucosal prolapse, solitary rectal ulcer and descending perineum syndrome), or obstructive defecation without anatomical alterations (pelvic floor dyssynergy or anismus). The diagnostic methods used (history and physical examination, colonic transit time, balloon expulsion test, proctography, anorectal manometry and electromyography) are reviewed. Conservative medical treatment and the indications for surgical treatment and its results are also discussed.

Constipation↗

Bordetella pertussis in the aetiology of chronic cough in adults. Diagnostic methods and clinic.

Cough is one of the most common complaints causing patients to seek medical attention, and chronic cough, defined as a cough period of at least three weeks, accounts for more than a third of referrals to a chest physician. Cough is an important factor in the spread and survival of microorganisms, but until recently little attention has been given to Bordetella pertussis (B. pertussis) in patients with chronic cough. This review summarizes the B. pertussis diagnostic methods--culture--polymerase chain reaction (PCR), and serology--and surveys the literature on B. pertussis and chronic cough in adults. There is growing evidence that B. pertussis is an important cause of persistent cough in adults; thus prevalence of pertusssis of 12.4-26% has been reported in studies from US, Australia and Germany. Recently we found evidence of pertussis as the cause of chronic cough in 16% of otherwise healthy adults in Denmark. Therefore, patients with chronic cough should be examined for B. pertussis infection. The demonstration of B. pertussis in an adult patient with chronic cough has two advantages: 1) the patient can be reassured that symptoms will disappear spontaneously, why more or less invasive examinations and empirical therapeutic trials can be omitted, 2) the source of infection can be eradicated, and contact persons, particularly non vaccinated infants in whom pertussis might be very severe, can be treated in order to avoid or attenuate clinical symptoms.

Adult↗

[Identification of species of Cyclospora isolates from patients by the PCR-based diagnostic methods].

Cyclospora cayetanensis is an intestinal coccidian parasite and known as a human pathogen causing watery diarrhea. Recently, Cyclospora organisms, morphologically indistinguishable from C. cayetanensis, were detected from the several species of primates, and three new species named, C. cercopitheci, C. colobi, and C. papionis, have been proposed to the isolates on the basis of the genetic differences. The infectivity of these species to humans is strictly unknown, and there is a possibility of infection with not only C. cayetanensis but also the species from primates among patients. Therefore, it is necessary for the accurate diagnosis of Cyclospora infection to distinguish among the Cyclospora species. In the present study, we identified species of Cyclospora isolates from patients by the PCR-based diagnostic method. Since the sequence of Cyclospora 18S ribosomal RNA gene generated with the primary pair CYC1 FE and CYC4RB is found to be variable among Cyclospora species, we applied the PCR-direct sequencing using above primers to identify species of the isolates. Consequently, the diagnostic fragment was amplified by the PCR in all isolates, and the sequence of the PCR product obtained from each isolate was completely identical to that of C. cayetanensis. Therefore, we identified the isolates from patients as C. cayetanensis. On the basis of the results obtained in the present study, it is supposed that the PCR-direct sequencing using the primer pair CYC1FE and CYC4RB is a useful tool for the distinction among Cyclospora species.

Animals↗

The diagnostic and predictive value of cerebrospinal fluid lactate in children with meningitis. Its relation to current diagnostic methods.

One hundred and thirty-three children with suspected meningitis aged from 11 days to 16 years were investigated with routine cerebrospinal fluid (CSF) laboratory methods: microscopy of a Gram-stained smear, bacterial culture, determination of leukocytes, lactate, and the CSF/blood glucose ratio. On the basis of bacterial cultures and clinical course, the children were classified into three groups: bacterial meningitis (n = 18), aseptic meningitis (n = 28), and a control group (n = 87). The main intention was to study the relation between current diagnostic methods and lactate. CSF lactate levels and cell counts, related significantly (p less than 0.01) better to the presence of bacterial meningitis than CSF/blood glucose ratios. Lactate levels exceed 2.4 mmol/l in all children with bacterial meningitis, but in none of the control group. Of 28 children with aseptic meningitis 3 had lactate in the range 2.5-2.7 mmol/l, while the others had values of 2.4 mmol/l or less. We consider CSF lactate to be the best predictor in the clinical decision to institute antibiotic treatment of children with suspected bacterial meningitis.

Adolescent↗

A novel diagnostic method for human immunodeficiency virus type-1 in plasma by near-infrared spectroscopy.

Presently, the diagnosis of virus infections is based mainly on serological assays. Although polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) have been increasingly used for the diagnosis of such viral infections, the risk of transfusion-transmitted blood-borne viruses remains. Furthermore, PCR and ELISA are expensive and time-consuming, and sometimes cause falsepositive or false-negative results. Therefore, a rapid, accurate and cost-effective diagnostic procedure is needed. We subjected plasma from individuals infected with human immunodeficiency virus type-1 (HIV-1), the causative agent of acquired immune deficiency syndrome (AIDS), as well as plasma from uninfected individuals as a control to near-infrared (NIR) spectroscopy, which may provide a rapid diagnostic method for HIV-1 infection without using any reagent. NIR spectra in the 600-1,000 nm region for plasma from pre-serologically HIV-1-infected individuals and healthy donors were subjected to partial least squares (PLS) regression analysis and leave-out cross-validation to develop a multivariate model to estimate the concentration of HIV-1. Simultaneously, the same plasma samples were examined for HIV-1 p24 by ELISA. The results obtained by the NIR spectroscopy model for HIV-1 yielded a good correlation with those obtained by the reference method (HIV-1 p24 ELISA). These results suggest that NIR spectroscopy using plasma could provide a rapid, accurate, cost-effective tool for large-scale diagnosis of HIV-1 infection.

Antigens, Viral↗

Polymerase chain reaction in cutaneous tuberculosis: is it a reliable diagnostic method in paraffin-embedded tissues?

BACKGROUND: Most cutaneous tuberculosis lesions contain few bacilli, so identification of Mycobacterium tuberculosis in conventional laboratory tests is difficult. In vitro amplification of specific DNA sequences using polymerase chain reaction (PCR) has become a valuable tool in the rapid detection of slow-growing organisms like M. tuberculosis. AIM: To investigate the presence of M. tuberculosis DNA in cutaneous tuberculosis. METHODS: Twenty-two archival biopsy specimens diagnosed as cutaneous tuberculosis were investigated for the presence of M. tuberculosis DNA by PCR. Normal skin samples of 29 healthy patients were used as a control. RESULTS: Amplification of the M. tuberculosis DNA was observed in one of the cutaneous tuberculosis specimens and in a healthy control. CONCLUSION: Although PCR is a rapid diagnostic method, fixation procedures may decrease its sensitivity.

Adolescent↗

A bridged diagnostic method for the monitoring of polymorphic discrete-event systems.

Diagnosis of discrete-event systems (DESs) is a challenging problem that has been tackled both by automatic control and artificial intelligence communities. The relevant approaches share similarities, including modeling by automata, compositional modeling, and model-based reasoning. This paper aims to bridge two complementary approaches from these communities, namely, the diagnoser approach and the active system approach, respectively. The more significant shortcomings of such approaches are, on the one side, the need for the generation of the global system model and, on the other, the lack of monitoring capabilities. The former makes the application of the diagnoser approach prohibitive in real contexts, where the system model is too large to be generated, even offline. The latter requires the completion of the system observation before starting the diagnostic task, thereby, making the monitoring of the system. impossible. The bridged diagnostic method subsumes, to a large extent on the peculiarities of the two approaches and is capable of coping with an extended class of DESs that integrate both synchronous and asynchronous behavior. The bridge is built by extending the active system approach by means of several enhanced techniques, which eventually, allow the efficient monitoring of polymorphic DESs. Upon the occurrence of each system message, two pieces of diagnostic information are generated, namely, the snapshot and historic diagnostic sets. While the former accounts for the faults pertinent to the newly generated message only, the latter is based on the whole sequence of messages yielded by the system during operation.

Algorithms↗

The diagnosis of urinary tract infections among pregnant women in rural Tanzania; prevalences and correspondence between different diagnostic methods.

BACKGROUND: To assess the prevalence of dysuria, dipsticks positive on nitrite and leukocyte esterase and positive Uricult dip slides among pregnant women in rural Tanzania. METHODS: 3,715 pregnant women were examined for dysuria and had their urine tested with nitrite and leukocyte esterase dipsticks and Uricult dipslides, at their first antenatal visit in 1995-96. RESULTS: The prevalences of positive symptoms and tests were as follows: dysuria 32%, nitrite 40.3%, leukocyte esterase 65.6%, and Uricult dip slides 16.4%. A general log-linear model where all four variables were analyzed simultaneously showed poor correspondence between the diagnostic methods. Odds ratio with 95% confidence intervals were as follows: dysuria vs. nitrite [1.6 (1.4 1.8)]. dysuria vs. leukocyte esterase [1.2 (1.0-1.4)], nitrite vs. leukocyte esterase [4.2 (3.6-4.9)], and leukocyte esterase vs. Uricult [1.4 (1.1-1.7)]. Dysuria and nitrite were not associated with Uricult dipslide. CONCLUSION: A high prevalence of positive tests, but a poor correspondence between the methods was found, emphasizing the need for more attention to the problem of urinary tract infections among pregnant women in developing countries, and the need for better screening tests for urinary tract infections in these countries.

Adolescent↗

Ductus arteriosus aneurysm imaging using modern diagnostic methods.

An aneurysm of the ductus arteriosus carries a high risk of rupture. The radiologic findings are described, based on a review of the literature, and on our experience of 5 patients, successfully diagnosed and treated. A left-sided mediastinal mass is always present, obscured only if the aneurysm has already ruptured. Although the lesion seems to be congenital, conventional radiology sometimes demonstrates wall calcifications. Ultrasonography is well suited to demonstrate the vascular nature of the mass, but interpretation may be difficult because of intervening air-containing lung parenchyma. CT, especially using dynamic scanning with contrast enhancement, is an excellent noninvasive diagnostic method. Angiography is frequently necessary to demonstrate patency or occlusion of the aortic and pulmonary ends of the ductus. The differential diagnosis must include a large number of mediastinal tumors. A temporary widening of the ductus in the newborn is common and must be differentiated from a true aneurysm. Surgical treatment today is usually successful.

Aneurysm↗

Mammography is an objective diagnostic method.

Six hundred mammograms from 307 consecutive symptomatic patients with a firm retrospective diagnosis were evaluated blindly and independently by two observers. Each observer identified 43 of 47 tumors (91 per cent) with predictive values of 0.63 and 0.68, respectively, for the positive statement, and 0.98 for the negative statement. The overall interobserver agreement with respect to malignancy was 94 per cent (Kappa 0.84) and concerning the diagnosis of simple cysts 91 per cent (Kappa 0.60). The frequency of subclinical cancer demonstrated by mammography in this material was higher than the prevalence of mammary carcinoma found by screening of risk group populations. Thus, mammography remains an objective and reproducible diagnostic method with distinct complementary value to clinical examination. By utilizing certain mammographic criteria for benign lesions it may be possible to reduce the number of biopsies presently performed on the basis of unspecific palpatory findings.

Adolescent↗

Anorectal Manometry as a diagnostic method in the neonatal period.

Presented are the results of manometric investigation of 63 neonates. The method was correct in 92% of all cases at first investigation, and if delay was justifiable on clinical grounds, this figure rose to 98%. Most problems in diagnosis using this method were related to abnormal smooth muscle contractility, which is regarded as being the most important single factor to determine. In patients in whom contractility was abnormal, sepsis, hypoxia, and hypothermia were associated with the generally poor clinical condition. The return of normal contractility paralleled the improvement in the patient's general clinical condition. Neither the maturity nor the size of the patient was felt to be a factor influencing the success or failure of manometry as a diagnostic method.

Anal Canal↗

Pinworm prevalence in California elementary school children, and diagnostic methods.

The pinworm prevalence among 302 children tested in 1980 in five Southern California elementary schools was determined to be 11.6%. The range was 7.3-15.4%. In a 1982 study involving 158 children in six schools, the prevalence was 21.6% (range 11.1-38.9%). The results of these studies are compared with those of a similar prevalence study done in the same area and in some of the same schools during the 5-year period 1960-1964. The prevalence for the earlier period, involving 700 children in six schools, was 34.6%, and ranged from 29.2-43.0%. A new, flexible, plastic pinworm slide was used in the 1980 and the 1982 studies. In the 1982 study, this diagnostic method was evaluated and compared for efficiency and use against the standard cellulose tape/glass slide. The two are equally effective in picking up eggs, and in reading quality. The plastic slide is easier to use and does not break.

California↗

[Positron emission tomography in neuroscience. An integrative part of clinical diagnostic methods and experimental research].

The role of molecular neuroimaging techniques is increasing in the understanding of pathophysiological mechanism of diseases. To date, positron emission tomography is the most powerful tool for the non-invasive study of biochemical and molecular processes in humans and animals in vivo. With the development in radiochemistry and tracer technology, a variety of endogenously expressed and exogenously introduced genes can be analyzed by PET. This opens up the exciting and rapidly field of molecular imaging, aiming at the non-invasive localisation of a biological process of interest in normal and diseased cells in animal models and humans in vivo. Besides its usefulness for basic research positron emission tomography has been proven to be superior to conventional diagnostic methods in several clinical indications. This is illustrated by detection of biological or anatomic changes that cannot be demonstrated by computed tomography or magnetic resonance imaging, as well as even before symptoms are expressed. The present review summarizes the clinical use of positron emission tomography in neuroscience that has helped elucidate the pathophysiology of a number of diseases and has suggested strategies in the treatment of these patients. Special reference is given to the neurovascular, neurodegenerative and neurooncological disease.

Animals↗

A simple diagnostic method for the differentiation of Tamm-Horsfall glycoproteins from healthy probands and those from recurrent calcium oxalate renal stone formers.

Tamm-Horsfall glycoproteins (THPs)* from healthy probands, and those from a majority of recurrent calcium oxalate renal stone formers, reveal different properties when analyzed using isoelectric focusing. The pl-values of THPs from healthy probands are approximately 3.5 while THPs from recurrent renal stone formers have pl-values between 4.5 and 6. The two groups of THPs exhibit completely different protein patterns in IEF. This proves the structural difference of these THPs. The differences in IEF analysis allow the differentiation between THPs from healthy probands and those from recurrent calcium oxalate stone formers. These differences could possibly be used as a simple diagnostic method for the recognition of recurrent calcium oxalate renal stone formers.

Biomarkers↗

Subclavian-axillary venous thrombosis: role of noninvasive diagnostic methods.

The diagnosis of primary subclavian axillary venous thrombosis (SAVT) was evaluated in eight patients to compare the accuracy of clinical diagnosis and noninvasive vascular evaluation with phlebography. Clinical evaluation led to three misdiagnoses: lymphedema (1), and inflammatory breast carcinoma (2). Doppler ultrasound detection of venous flow performed on three patients detected SAVT in only one. Plethysmography also performed on three patients led to unquestionable diagnosis in only one. Plethysmography also performed on three patients led to unquestionable diagnosis in only one. Phlebography positively identified SAVT in all patients and showed bilateral disease in one. Two patients had pulmonary embolism, and in one, permanent sequelae developed, thus emphasizing the necessity for energetic treatment of SAVT. Because of the risks of therapy and the inaccuracy of other diagnostic methods, SAVT should be positively identified by phlebography if anticoagulation is considered. Doppler and plethysmography are useful to rule out concomitant leg phlebothrombosis, to evaluate the arterial sector, and to document venous hemodynamic recovery after SAVT.

Adolescent↗