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PubMed1990

Monitoring rejection after heart transplantation: cytoimmunological monitoring on blood cells and quantitative birefringence measurements on endomyocardial biopsy specimens.

Cytoimmunological monitoring and quantitative birefringence measurements were used as potential aids in diagnosing acute rejection after heart transplantation instead of histopathological assessment of the endomyocardial biopsy specimen alone. Cytoimmunological monitoring was based on morphological inspection and quantitation of mononuclear cells, particularly activated lymphoid cells. Quantitative birefringence measurements comprise a variable for myocyte contractile function. Its read out is the ratio of the degree of birefringence before contraction to that after. Cytoimmunological monitoring indicated significantly higher concentrations of activated lymphocytes in moderate or severe acute rejection, and quantitative birefringence measurements indicated decreased myocyte function during severe and resolved or resolving rejection. Cytoimmunological monitoring and quantitative birefringence measurements were diagnostically most useful in terms of sensitivity, specificity, and predictive value, when only data gathered before the first episode of acute rejection were considered. For cytoimmunological monitoring, diagnostic relevance was optimal when the data were expressed as relative proportions of activated lymphocytes. The quantitative birefringence measurements correlated best with analysis of the endomyocardial biopsy specimen when a cut off value of 1.25 was used. When both methods for diagnosing acute rejection were analysed together, no improvement in sensitivity (value 0.44) was found, but the specificity increased to 0.98 and the predictive value to about 0.80. It is concluded that cytoimmunological monitoring is a useful, non-invasive additional method for diagnosing the first period of acute rejection after heart transplantation and that quantitative birefringence measurements give valuable information on the extent of myocyte damage.

Birefringence↗
PubMed1992

Detection of hepatitis B pre-core mutant by allele specific polymerase chain reaction.

AIM: Development of a specific polymerase chain reaction (PCR) assay for detection of the pre-core, stop codon, mutant of hepatitis B virus (HBV). METHODS: PCR primers, specific at the 3'-end for nucleotide 1896 of either the pre-core, stop codon, mutant or wild type HBV, were synthesised using published sequence data. Positive control templates for both types of virus were synthesised by the PCR, incorporating sequences specific for each virus type at the appropriate position. These templates were used to optimise the specificity of the procedure. Formalin fixed, paraffin wax embedded human tissue from acute or fulminant HBV hepatitis from Hong Kong or Oxford was then investigated for presence of mutant or wild type virus. The HBV DNA was amplified from this tissue using a two step procedure, with an initial amplification phase followed by a second diagnostic phase on optimally diluted target DNA. RESULTS: Specific detection of mutant or wild type HBV was achieved. An important factor in determining specificity was the temperature of annealing, 70 degrees C proving to be highly specific. To overcome the inherent variation of target copy number in clinical samples and to provide an intrinsic positive control, it was important to generate and standardise the amount of target HBV used for the specific PCR. Two cases of fulminant hepatitis and four cases of acute hepatitis from Hong Kong, and one case of fulminant hepatitis from Oxford, contained only wild type HBV, with no evidence of a mutant virus. CONCLUSION: This method can be applied to FFPE tissues. It is rapid, non-radioactive, and specific for the stop codon mutation at nucleotide 1896 of HBV. Preliminary investigation of a small number of cases of fulminant hepatitis from Oxford and Hong Kong showed only wild type virus. The result differs from results published from Japan and Israel.

Alleles↗
PubMedDate not supplied

Artifacts in CT: recognition and avoidance.

Artifacts can seriously degrade the quality of computed tomographic (CT) images, sometimes to the point of making them diagnostically unusable. To optimize image quality, it is necessary to understand why artifacts occur and how they can be prevented or suppressed. CT artifacts originate from a range of sources. Physics-based artifacts result from the physical processes involved in the acquisition of CT data. Patient-based artifacts are caused by such factors as patient movement or the presence of metallic materials in or on the patient. Scanner-based artifacts result from imperfections in scanner function. Helical and multisection technique artifacts are produced by the image reconstruction process. Design features incorporated into modern CT scanners minimize some types of artifacts, and some can be partially corrected by the scanner software. However, in many instances, careful patient positioning and optimum selection of scanning parameters are the most important factors in avoiding CT artifacts.

Artifacts↗
PubMed2004

Quantitative detection of circulating tumor cells in cutaneous and ocular melanoma and quality assessment by real-time reverse transcriptase-polymerase chain reaction.

PURPOSE: Inconsistent reports on the detection of melanoma cells in peripheral blood by reverse transcriptase-PCR (RT-PCR) have resulted in uncertainty on the prognostic value of circulating melanoma cells. EXPERIMENTAL DESIGN: We developed real-time RT-PCR assays for quantitation of tyrosinase, MelanA/MART1, and gp100 and for porphobilinogen deaminase housekeeping gene. Melanoma tissue (n = 18), peripheral blood samples from healthy donors (n = 21), and patients with cutaneous (n = 122) and uveal (n = 64) melanoma from our institution were analyzed. For quality control, an additional 251 samples from ongoing multicenter studies were compared with in-house samples. RESULTS: Tyrosinase was not detected in healthy donor blood samples. For the two other markers, cutoff values had to be defined to distinct patient samples from controls. Patients with stage IV uveal and cutaneous melanoma expressed all three markers more frequently and at higher levels in peripheral blood as compared with earlier stages. The variation of expression was 4 logs and correlated with tumor load and serum lactate dehydrogenase. In 2 of 3 uveal melanoma patients, detection of circulating tumor cells preceded the development of liver metastases. The diagnostic sensitivity was optimal in blood samples containing >0.1pg/ microl porphobilinogen deaminase (95.7% of in-house samples and 57.4% of multicenter samples). CONCLUSIONS: Real-time RT-PCR is able to quantitatively define the quality of a sample and provides quantitative data for melanoma markers. Disparities in the results of previous studies may be attributable to undetected differences in sample quality. The prognostic relevance of this assay is currently under evaluation in several prospective randomized trials.

Antigens, Neoplasm↗
PubMed2000

The value of urodynamics in laser prostatectomy.

OBJECTIVE: To present the results of laser prostatectomy on urodynamic parameters, and to address the role of pressure/flow studies as diagnostic tools for optimal selection of candidates for this treatment modality. MATERIAL AND METHODS: The world literature, available on Medline, presenting urodynamic parameters in patients subjected to laser prostatectomy was studied. We compared the data of different series, and when it was feasible from intrinsic features of a particular study, urodynamic results were plotted on the ICS Provisional Nomogram. RESULTS: A general shift to a less obstructive status has been documented in all series, using different methods of data interpretation. No clear differences, in terms of elimination of obstruction, could be detected among different types of laser. Plotting the data on the ICS Provisional Nomogram, most series slide from the obstructed to the unobstructed zone. The observation that clearly obstructed groups accomplish the most impressive results, further emphasizes the value of urodynamics in the initial evaluation of benign prostatic hyperplasia patients by assisting in the appropriate choice of the therapeutic modality. CONCLUSIONS: Using the objective parameters of infravesical obstruction, laser prostatectomy has proved an effective treatment of benign prostatic hyperplasia. The role of pressure/flow studies in patient selection is justified, as this investigation permits identification of those cases who are going to have a direct benefit from a desobstructive procedure.

Humans↗
PubMedDate not supplied

The psychology of good judgment: frequency formats and simple algorithms.

Mind and environment evolve in tandem--almost a platitude. Much of judgment and decision making research, however, has compared cognition to standard statistical models, rather than to how well it is adapted to its environment. The author argues two points. First, cognitive algorithms are tuned to certain information formats, most likely to those that humans have encountered during their evolutionary history. In particular, Bayesian computations are simpler when the information is in a frequency format than when it is in a probability format. The author investigates whether frequency formats can make physicians reason more often the Bayesian way. Second cognitive algorithms need to operate under constraints of limited time, knowledge, and computational power, and they need to exploit the structures of their environments. The author describes a fast and frugal algorithm. Take The Best, that violates standard principles of rational inference but can be as accurate as sophisticated "optimal" models for diagnostic inference.

Algorithms↗
PubMed2003

Placental 11 beta-hydroxysteroid dehydrogenase-2 and fetal cortisol/cortisone shuttle in small preterm infants.

Glucocorticoids rate among the most controversial topics in today's perinatology and neonatology. Many sick preterm infants exhibit signs of adrenal insufficiency, the etiology, diagnostic criteria, and optimal treatment of which are under debate. Moreover, most of these infants are exposed to pharmacological glucocorticoid doses both in utero and after birth. In face of this, surprisingly little is known about the physiological glucocorticoid exposure before early preterm birth. This exposure is highly variable and mainly regulated by the placental enzyme 11 beta-hydroxysteroid dehydrogenase-2 (11 beta-HSD2), which converts excess cortisol (F) to inactive cortisone (E). Impaired activity of this enzyme is common in intrauterine growth restriction and preeclampsia, conditions frequently associated with early preterm birth. To identify clinical determinants associated with decreased placental 11 beta-HSD2 function, we studied 107 small preterm infants [mean birth weight, 1067 g (range, 395-2453 g); gestational age, 28.2 wk (range, 22.4-32.0 wk)] by determining their placental 11 beta-HSD2 activity rate (per milligram protein) and total activity (per placenta) as well as cord vein F and E concentrations. An E/(E+ F) ratio expresses the overall balance of the F/E shuttle. There were positive correlations between relative birth weight and placental 11 beta-HSD2 activity rate (r = 0.30; P = 0.002) and total activity (r = 0.56; P < 0.0001) as well as E/(E+ F) ratio (r = 0.27; P = 0.01) and E concentration (r = 0.32; P = 0.003). Infants with increased umbilical artery resistance had lower total placental 11 beta-HSD2 activity (P = 0.02), E/(E+ F) ratio (P = 0.04), and E concentration (P = 0.0002). Gestational age was inversely associated with placental 11 beta-HSD2 activity rate (r = -0.25; P = 0.009). We conclude that, in small preterm infants, reduced placental 11 beta-HSD2 function is associated with low relative birth weight and severe fetal distress. Whether these conditions are associated with early postnatal adrenal insufficiency or long-term cardiovascular risk remains an important issue for further study.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1997

Strategies for suppression, containment, and eradication of resurgent tuberculosis.

This review provides strategies for the suppression, containment, and eventual eradication of resurgent tuberculosis. Some ethnic minority communities are at greatest risk because of the prevalence of human immunodeficiency virus/acquired immunodeficiency syndrome, poverty and malnutrition, congregate living situations, aberrant lifestyles, illegal immigration, and underemployment among these populations. Proposed strategies include the education of the population at risk as well as health care providers to permit the optimization of preventive, diagnostic, and therapeutic technologies. Also necessary is the development of effective, safe, newer medications to enhance patient compliance and decrease drug resistance. Strategic planning embraces national socioeconomic policy to permit adequate resources to combat poverty and malnutrition, to rebuild the infrastructure of the public health system, and to improve access to health care among rural and urban dwellers. It is concluded that these efforts must continue to ensure the eradication of tuberculosis.

Adult↗
PubMed2006

Clinical genetic evaluation of the child with mental retardation or developmental delays.

This clinical report describes the clinical genetic evaluation of the child with developmental delays or mental retardation. The purpose of this report is to describe the optimal clinical genetics diagnostic evaluation to assist pediatricians in providing a medical home for children with developmental delays or mental retardation and their families. The literature supports the benefit of expert clinical judgment by a consulting clinical geneticist in the diagnostic evaluation. However, it is recognized that local factors may preclude this particular option. No single approach to the diagnostic process is supported by the literature. This report addresses the diagnostic importance of clinical history, 3-generation family history, dysmorphologic examination, neurologic examination, chromosome analysis (> or =650 bands), fragile X molecular genetic testing, fluorescence in situ hybridization studies for subtelomere chromosome rearrangements, molecular genetic testing for typical and atypical presentations of known syndromes, computed tomography and/or magnetic resonance brain imaging, and targeted studies for metabolic disorders.

Child↗
PubMed1988

Computer assessment of the intrapartum cardiotocogram. I. Methods of data reduction and diagnostic procedure.

To solve the problem of low predictive values in the visual assessment of the CTG, several computer programs have been designed. Only a few of those programs describe the CTG automatically and thus consistently. The aim of this study was to construct a diagnostic procedure for computer-aided automatic assessment of the CTG. A computer program quantified 17 variables of the CTG. Within a window of user-defined length, a second program calculated the number of measurements, the mean, the trend, and the coefficient of variation of each of the 17 variables, and produced a total of 56 distinct subvariables. A discriminant procedure was set up which could use any number and combination of the 56 subvariables to calculate the probability of a CTG derived from a compromised infant. The diagnostic procedure was optimized by "direct forward search" for the combination of subvariables discriminating best between normal and compromised infants. Using the last half hour of the first stage of labor, 50 CTGs entered the optimizing procedure. A combination of nine subvariables was found. In a separate paper its performance is compared with that of clinicians.

Cardiotocography↗
PubMed1983

A description of diagnostic strategies in jaundice.

Diagnostic strategies applied in 144 consecutive patients with jaundice were investigated. Diagnostic hypotheses formed on the basis of initial data--history, physical findings, and results of routine laboratory tests--enabled the clinician to adopt a single-target strategy in 75 patients and a multi-target strategy in 61 patients. Four patients died very early in the course of events and another four were excluded from analysis because they were judged not to benefit from further investigations. The single-target strategy, in which the clinician explored one diagnostic hypothesis only, often led to a short diagnostic process (mean, 11 days), and in 89% of the patients the clinician's hypothesis was correct. In the multi-target strategy several diagnostic hypotheses were evaluated. In these patients the correct diagnosis was included in the first set of hypotheses in 84%, and the mean duration of the diagnostic process was 25 days. Patients with cholestatic jaundice presented the most difficult diagnostic problem, and most of these were investigated by a multi-target strategy. The possibility of an extrahepatic obstruction often forced the clinician to use invasive procedures to rule out this diagnosis. Considerable time was spent in observing the clinical course and waiting for investigations to be carried out. To reduce the investigative cost, controlled studies of diagnostic value and optimal order of investigations are warranted.

Adult↗
PubMed1986

Serendipity in cholangiography.

Seventeen of 107 consecutive direct cholangiography demonstrated serendipitous and unusual but significant contrast collections. The indications for and routes of cholangiography, correlative imaging procedures and outcome were retrospectively analysed. There was 6 bilomas, 3 aberrant bile ducts, 3 hepatic and 3 subphrenic abscesses and 2 gastrobiliary fistulae. Other contrast deposits were intra, perivascular, paraductal, interstitial and gastric reflux. While cholangiography cannot be proposed as the primary imaging modality in any of the above entities, the described incidental but significant cholangiographic features should be recognised, to optimize the total diagnostic yield (particularly in centres in developing economies, where cross-sectional imagers are scarce), redirect diagnostic endeavours to the real source of patients' problems, and discriminate normal and procedure-related from concurrent pathological accumulations, which may require specific therapy.

Biliary Tract Diseases↗
PubMed2002

Evaluating the Impact of an Educational Program on Practice Patterns of Canadian Family Physicians Interested in Depression Treatment.

BACKGROUND: Depression is frequently unrecognized and undertreated. Therefore, there is a need to increase the knowledge and skills of primary care physicians regarding the diagnosis and treatment of depression. The aim of this study was to provide, and evaluate the impact of, a brief educational program with a number of practice tools and resources in order to improve family physicians' knowledge, diagnosis, and treatment of depression. METHODS: Two educational programs (general and enhanced) were delivered to family physicians interested in depression treatment. The enhanced program focused on more practical clinical issues such as use of diagnostic and symptom assessment tools, recommended dosing of citalopram, how to initiate and discontinue treatment, and relapse prevention. Physicians' knowledge of depression was assessed pretraining and posttraining. Chart audits were conducted for 6 months. Primary endpoints were recognition of depression and pharmacologic management (initial dose, maximum dose, length of treatment, adverse events, and concomitant psychotropic drugs). Secondary endpoints were patient satisfaction with treatment, compliance, withdrawal from the study, treatment outcome, use of adjunctive psychotherapy, and number of office visits. RESULTS: There was a global increase in physicians' knowledge of depression in the short term. Physicians in the enhanced group were more likely to use a symptom-based diagnostic checklist, record the diagnosis of depression, and prescribe the recommended initial dose of citalopram, and they referred less frequently for adjunctive psychotherapy. No difference between educational intervention groups was found in patient satisfaction, compliance, and treatment outcome. CONCLUSIONS: A well-designed brief, simple, and low-cost educational program can increase family physicians' knowledge of depression, improve their diagnostic skills, and optimize their treatment of depression.

Journal Article↗
PubMedDate not supplied

Acromegaly as an endocrine form of myopathy: case report and review of literature.

OBJECTIVE: To describe a case of muscle weakness in a patient with acromegaly and to review the pathophysiologic features of this disorder. METHODS: We present the clinical, laboratory, electromyographic, and muscle biopsy findings in our patient and review related reports in the literature. RESULTS: A 58-year-old woman with acromegaly presented with complaints of bilateral hip pain, weakness, and instability 8 months after transsphenoidal resection of a growth hormone (GH)-secreting pituitary macroadenoma. She had biochemically normal thyroid and adrenal function and no evidence of any neuropathy, inflammatory myopathy, or rheumatologic disorder to explain her symptoms. Investigations revealed increased levels of GH, insulin-like growth factor-I, serum creatine kinase (CK), and the MB fraction of CK, normal results of nerve conduction studies, and nonspecific findings on electromyography and muscle biopsy. A review of the literature revealed that although muscle weakness is a well-recognized feature of acromegaly, only a few cases similar to ours have been reported since acromegaly was first described in the late 1800s. Little is known about the natural history, best diagnostic approach, and optimal therapy for this debilitating complication. CONCLUSION: Muscle weakness in acromegaly is common and may result from a combination of the direct effect of GH excess on muscle and other metabolic derangements (hypothyroidism, hypoadrenalism, or diabetes). Mechanical factors may also contribute, such as joint laxity in conjunction with hypermobility. Affected patients may benefit from a reduction in GH levels and physiotherapy for adaptive training. Persistently increased serum CK levels in a patient with diabetes, for whom no other cause is found, should prompt an investigation for acromegaly. More research into this aspect of acromegaly is needed for enhancement of our understanding of, and therapy for, this debilitating condition.

Acromegaly↗
PubMed2004

[Reversible dementias, do they exist?].

Due to the increase of the life expectancy the prevalence of the patients with dementia in the services of Internal Medicine is very high (30% in the patients with more of 80 years old). The incidence of the potentially reversible dementias is very different in the publications consulted (10-30%). The objective of these study is to know the real incidence of these dementias and which is the best diagnostic protocol to optimize the resources. The conclusions obtained in the bibliographical review it is that the effect of this type of dementias is minor that the mentioned (1.5-3%).

Dementia↗
PubMed2000

[Sturge-Weber syndrome. The current neuroradiologic data].

Sturge-Weber syndrome (SWS) is a rare congenital sporadic disease with neuro-ocular and cutaneous vascular findings. Clinically, the full-blown condition consists of a facial port-wine stain (PWS) involving the V1 facial trigeminal skin area, alone or in combination with V2 and V3PWS, seizures and ocular abnormalities (glaucoma and choroidal angioma). Radiologically, a leptomeningeal (pial) capillary and venous malformation, mostly located in the parieto-occipital area, cerebral atrophy and calcifications are demonstrated. An ipsilateral enlarged choroid plexus may be an early anatomic symptom. Developmental venous anomalies (DVA) of the brain are sometimes associated. MR with gadolinium enhancement is the optimal neuro-diagnostic imaging technique for the screening of infants with an at-risk V1PWS, as well as for the follow-up of patients with evidence SWS. Accelerated myelination in the involved hemisphere may be an early diagnostic feature before 6 months of age. Later, hyperintensity of white matter on T2 is considered a symptom of gliosis. Clinically, progression of the diseases is associated with anatomic changes and correlates with the extent of the pial vascular anomaly, extent and severity of cerebral atrophy, and white matter abnormalities. A neonatal neuro-imaging work-up, using CT or MRI, may not demonstrate the pial anomaly and should be repeated after 6 to 12 months in an at-risk infant with V1PWS.

Brain↗
PubMed2001

Contrast-enhanced ultrasound Doppler examination of the retrobulbar arteries.

PURPOSE: To evaluate the diagnostic usefulness of an ultrasound contrast agent in examination of the retrobulbar arteries. MATERIAL AND METHODS: Ten healthy volunteers received a galactose-based echo-contrast medium (Levovist) by i.v. infusion. The ophthalmic, central retinal, the nasal and the temporal posterior ciliary arteries and the short ciliary arteries were studied in 19 eyes by color and spectral Doppler ultrasonography before and after contrast administration. Peak systolic and end diastolic velocities and spectral Doppler indices (pulsatility and resistive) were assessed. The quality of the spectral and color Doppler imaging of the arteries were visually graded on a 5-point scale. RESULTS: There were significant differences in pre- and post-contrast peak systolic velocities in the ophthalmic arteries (p<0.05), but not in the other retrobulbar arteries, or in any of the spectral Doppler indices. After contrast administration the mean spectral Doppler score for vessels poorly visualized before contrast increased from 2.2 (+/-0.4) to 3.1 (+/-0.9). The number of short ciliary arteries with sufficient spectral Doppler quality increased from 7 prior to contrast to 14 following contrast. Prior to the infusion of Levovist, 62 (73%) out of 85 retrobulbar arteries could be evaluated with a sufficient spectral Doppler quality. Following the administration of contrast 66 (78%) arteries had sufficient spectral Doppler quality. However, by combining the results of the pre- and post-contrast examinations, sufficient spectral Doppler quality was obtained in 77 (91%) of the 85 retrobulbar arteries. CONCLUSION: Contrast enhancement increased the number of detectable retrobulbar vessels. However, in the case of good quality pre-contrast imaging of the retrobulbar vessels, the use of Levovist did not add any substantial diagnostic information. The optimal spectral Doppler results were obtained when both pre- and post-contrast examinations were performed.

Adult↗
PubMed2001

[Thoracic outlet syndrome].

Thoracic outlet syndrome (TOS) is due to compression/irritation of brachial plexus elements ("neurogenic TOS") and/or subclavian vessels ("vascular TOS") in their passage from the cervical area toward the axilla. The usual site of entrapment is the interscalenic triangle. TOS is a highly controversial subject in regard to its incidence, diagnostic criteria and optimal treatment. Constitutional factors--osseous or more often fibromuscular--and external factors such as trauma predispose to the development of TOS. Various clinical pictures include pain in the cervical region and arm, paresthesias, aggravated by overhead positions of the arms, hand intrinsic muscle deficit/atrophy, easy fatiguability, paleness, coldness of hand. The clinical examination may be entirely normal or show cervical and scapular muscle spasm, tenderness of supraclavicular area, radial pulse attenuation upon positional maneuvers, sensory and/or motor deficit, usually of C8/T1 distribution. The diagnosis is based on clinical evaluation and absence of other relevant pathology. Sometimes TOS can enhance symptoms consecutive to cervical or supraclavicular lesions. Cervical spine and distal peripheral nerves are investigated by radiological and electrophysiological studies. Unless there is significant motor deficit or subclavian artery compression, the treatment should be kept conservative as long as possible, by adapted physical therapy. In case of neurological deficit or symptoms unresponsive to medical treatment, the patients will--like in other nerve entrapment syndromes--be helped by decompressive surgery, nowadays preferably performed via an anterior supraclavicular approach.

Brachial Plexus↗