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Can the cost savings of eliminating urine microscopy in biochemically negative urines be extended to the pediatric population?

The authors determined the value of performing urine microscopy on biochemically negative urine specimens in a pediatric population. Four reactions of the Chemstrip-9TM (Biodynamics, Inc., Indianapolis, IN) were used as biochemical indicators, namely, protein, occult blood, leukocyte esterase, and nitrite. Out of 1,016 urine specimens thus studied, 310 were true positive. Eleven specimens reacted biochemically in the absence of significant microscopic findings (false positive), 668 specimens were negative by the Chemstrip-9 and were either negative microscopically or had less than five white blood cells (WBCs) per high power field (HPF) and were considered true negatives. Twenty-seven specimens had negative biochemical indicators, in spite of positive microscopy; of these specimens, only seven had more than ten WBCs per HPF, 17 had five to ten WBCs per HPF, and three had five to ten red blood cells per HPF. The sensitivity of the four parameters for predicting significant microscopy of urinary sediment is 91% and the specificity is 98%. The predictive value of a negative result is 96.1%, and that of a positive result is 96.5%. The authors therefore conclude that urine microscopy is unnecessary in biochemically negative urine specimens from pediatric patients who are asymptomatic for urinary tract disease.

Child↗

X-ray microscopy of human spermatozoa shows change of mitochondrial morphology after capacitation.

Using X-ray microscopy two morphologically distinct states were observed of the human spermatozoan mitochondria: (i) compact and tightly wrapped around the axoneme, and (ii) morphologically transformed, i.e. with circular areas of high X-ray transmission, either loosely wrapped around the axoneme or distended. The spermatozoa were examined at two stages of their post-ejaculation maturation process, i.e. as present in fresh ejaculated semen and after in-vitro capacitation. X-ray microscopy allowed sample preparation that was as simple as for conventional light microscopy whilst giving high resolution (30 nm) imaging of samples in liquid media compatible with the requirements of live biological specimens. The specimens were not fixed, stained or metal coated. These features make X-ray microscopy useful in the study of cells, particularly cells in suspension. The relative frequencies of the two morphological states of the mitochondria in seminal plasma and after in-vitro capacitation were compared. In seminal plasma, almost all spermatozoa had compact and tightly wrapped mitochondria. After harvesting by swim-up technique, an increase in the morphologically transformed state had occurred. However, the greatest increase in the morphologically transformed state occurred when the sample had been incubated under capacitating conditions. In this case almost all spermatozoa had morphologically transformed mitochondria.

Humans↗

Embedment-free section electron microscopy.

Because of potential hindrance of clear viewing in epoxy sections of biological entities having an electron density similar to and lower than that of epoxy resin, the author has stressed that the embedment-free section electron microscopy is necessary for re-examination and/or clarification of biological specimen structures, and that the embedment-free electron microscopy is reliably done by using water-soluble polyethylene glycol (PEG) as a transient embedding media and by critical point-drying of embedment-free sections after de-embedment of PEG by immersion of semithin sections into water. With the embedment-free electron microscopy, the author has presented five major findings: the appearance of microtrabecular lattices with different compactnesses in various cells and in intracellular domains of a given cell, the faithful reproduction of microtrabecula-like strand lattices in vitro with increasing compactnesses from artificial protein solutions at correspondingly increasing concentrations, the appearance of more compact lattices from gelated gelatin than from solated gelatin at a given concentration in vitro, the changeability in compactnesses of the microtrabecular lattices by hyper- or hypotonic shock treatments of cells, and the confined appearance of an intracellular protein in the centripetal demilune of centrifuged ganglion cells which is occupied with the microtrabecular lattices of a substantial compactness. From these findings, several conclusions are drawn: individual strands themselves of the microtrabeculae are meaningless, the appearance of microtrabeculae represents the presence of proteins at a certain concentration, and it is therefore likely that the aqueous cytoplasm is equivalent to the aqueous solution. In addition, it is possible that the appearance of two contiguous lattice domains exhibiting different compactnesses in a given cell may represent the occurrence of a contiguity of sol to gel states of cytoplasmic domains. It is thus proposed that the localization and movement of intracellular organelles are controlled not only by the cytoskeletons but also by the concentration and sol/gel states of intracellular proteins. In addition, several potential usefulness of the embedment-free electron microscopy has also been demonstrated.

Cytoskeleton↗

"Virtual microscopy" and the internet as telepathology consultation tools: diagnostic accuracy in evaluating melanocytic skin lesions.

The Internet offers a widely available, inexpensive tool for telepathology consultations. It allows the transfer of image and text files through electronic mail (e-mail) or file transfer protocols (FTP), using a variety of microcomputer platforms. We studied the use of the Internet and "virtual microscopy" tools for the diagnosis of 35 skin biopsies, including a variety of benign and malignant melanocytic lesions. Digitized images from these lesions were obtained at 40x and 100x optical magnification, using a high resolution digital camera (Microlumina, Leaf Systems, Southborough, MA), a light microscope with a phototube adapter and a microcomputer with a Pentium 166 MHz microprocessor. Two to four images of each case were arranged on a "canvas" to represent the majority or an entire biopsy level, using Photoshop software (Adobe Systems Inc., San Jose, CA). The images were compressed using Joint Photographers Expert Group (JPEG) format. The images were then viewed on a computer video monitor in a manner that closely resembles light microscopy, including scrolling by using the "hand tool" of Photoshop and changing magnification digitally up to 4 times without visible image degradation. The image files, ranging in size from 700 kilobytes to 2.1 megabytes (average 1.6 megabytes) were attached to e-mail messages that contained clinical information, using standard Multipurpose Internet Mail Extension (MIME) protocols and sent through the Internet, for interpretation by a dermatopathologist. The consultant could open the images from the e-mail message, using Microsoft Outlook Express (Microsoft Corp., Redmond, WA) and Photoshop software, scroll them, change magnification and render a diagnosis in a manner that closely simulates light microscopy. One hundred percent concordance was obtained between the telepathology and traditional hematoxylin and eosin slide diagnoses. The Internet and relatively inexpensive "virtual microscopy" tools offer a novel technology for dermatopathology consultations. Potential applications of this technology to pathology and technical problems posed by the use of an open, widely distributed network to share sensitive medical information are discussed.

Biopsy↗

Visualization of human herpesvirus type 8 in Kaposi's sarcoma by light and transmission electron microscopy.

BACKGROUND: Human herpesvirus type 8 (HHV-8) has been associated with Kaposi's sarcoma, body cavity-based lymphoma (BCBL), and multicentric Castleman's disease through DNA, in situ hybridization, and serologic studies. HHV-8 has been visualized only in HHV-8-positive/Epstein-Barr virus (EBV)-negative/ cytomegalovirus (CMV)-negative BCBL cell lines, but not in HHV-8-positive/EBV-negative/ CMV-negative Kaposi's sarcoma lesions. DESIGN: Kaposi's sarcoma of the skin, lymph node, and spleen from three patients with AIDS were analysed for HHV-8, EBV and CMV DNA by polymerase chain reaction (PCR), for HHV-8 RNA (Tl.1 riboprobe) by in situ hybridization (ISH), for viral inclusions by light microscopy, and for herpesviruses by transmission electron microscopy (TEM). Sections were also labeled with Tl.1 counterstained with CD34, an endothelial cell marker. RESULTS: The skin lesion was DNA PCR-positive for HHV-8 and CMV (nested, but not single PCR), the lymph node was positive for HHV-8 and EBV, and the spleen was positive for only HHV-8. TEM revealed infection by a virus displaying the typical morphology and cytopathicity of herpesviruses. Hexagonal nucleocapsids and mature enveloped virions were present in vasoformative spindle cells and mononuclear cells, often resembling lymphocytes. Extrapolating from TEM to standard light microscopy on hematoxylin and eosin-stained paraffin sections, eosinophilic, targetoid intranuclear inclusions were identified within spindle cells which often lined vascular lumina. The Tl.1-riboprobe labeled CD34+ spindle cells containing intranuclear inclusions, as well as mononuclear cells within Kaposi's sarcoma and residual lymphoid tissue. CONCLUSION: The herpesvirus visualized in Kaposi's sarcoma lesions has morphologic and cytopathic features typical of human herpesviruses, productively infects vasoformative spindle cells and mononuclear cells, and is consistent with HHV-8. It can also form intranuclear inclusions that are identifiable by light microscopy in hematoxylin and eosin sections and by ISH.

Herpesvirus 8, Human↗

Characterization of fibrous retrocorneal membrane by confocal microscopy.

PURPOSE: To study the appearance of a fibrous retrocorneal membrane as seen by confocal microscopy. METHODS: A 67-year-old white woman with a history of multiple ocular surgeries, including repeated penetrating keratoplasties for aphakic bullous keratopathy, developed a retrocorneal membrane in the right eye. The membrane was first noticed 3 years after the last corneal transplant and remained stable subsequently. The patient was examined by in vivo white light tandem-scanning confocal microscopy. RESULTS: At the level of the retrocorneal membrane, confocal microscopy disclosed the presence of a hyperreflective fibrous-appearing layer. Normal endothelial cells could not be found. Anterior to the hyperreflective layer, activated keratocytes were identified. CONCLUSION: Confocal microscopy may allow noninvasive diagnosis of fibrous retrocorneal membrane. Additionally, our data suggest that the posterior keratocytes might play a role in the production and deposition of fibrous tissue.

Aged↗

Confocal microscopy in multiple myeloma crystalline keratopathy.

PURPOSE: To report confocal microscopy findings of a patient with multiple myeloma crystalline keratopathy and the response to treatment. METHODS: Confocal microscopy images of the cornea were taken OU and the corneal crystals analyzed using the Cell Counter software. RESULTS: Numerous hyperreflective globules 6-11 nm in size were located within the corneal epithelium and anterior stroma. These crystals obscured normal architectural detail of the cornea. After 6 months of chemotherapy, confocal microscopy was repeated and demonstrated decrease in the size and number of hyperreflective globules. CONCLUSION: Confocal microscopy can enable the clinician to monitor the clinical response of multiple myeloma crystalline keratopathy to chemotherapeutic agents.

Aged↗

A probe for specimen magnetic resonance microscopy.

One of the primary limits to spatial resolution in magnetic resonance (MR) microscopy is the limited signal. The purpose of this study is to build a radiofrequency (rf) probe for MR microscopy of fixed specimens at 300 MHz. The design criteria for the probe were (1) high sensitivity; (2) good rf homogeneity; (3) minimization of BO variations. All probes were Helmholtz pairs operating at 300 MHz. Coils were constructed from copper/Teflon/copper microwave substrate which eliminated susceptibility problems from solder and discrete capacitors. Signal-to-noise ratio (SNR) was compared with a conventional solenoid. Phantoms of agar gels and saline-filled tubes were used to characterize the SNR and homogeneity. SNR measurements of the coil pairs showed a marked improvement (up to 60%) over that of the reference solenoid. The region of homogeneity was defined as a 10% variation in signal intensity. This correlated with the coil's inner diameter. Graphs of SNR versus diameter, separation, and copper foil width allowed for optimization of the structure. Using this coil, MR microscopy is now possible on small, fixed specimens with pixels as small as 20 x 20 x 30 microns. Work is currently under way exploiting the SNR and homogeneity provided by this probe to determine the degree to which MR microscopy might add to the pathologists' diagnostic tools.

Copper↗

Electron microscopy in determining origin of metastatic adenocarcinomas.

Light microscopy has limited value in predicting where the primary site of a metastatic adenocarcinoma might be located. In our series, electron microscopy was useful in determining the primary site in approximately 85% of patients with a metastatic adenocarcinoma of unknown origin. This study is based on the ultrastructural examination of more than 100 such cases. In the remaining 15% of the cases, electron microscopy usually provided assistance in reducing the differential diagnosis to a minimum, usually to two possible primary sites. The majority of the metastatic adenocarcinomas showed rather specific ultrastructural features to suggest the site of origin. This application of electron microscopy has never been fully explored and has considerable clinical importance and economic impact in health care systems. An extensive work-up to determine the primary site, with its inconvenience to patient and family, as well as delay in adequate treatment, can be avoided with early diagnosis of the primary site.

Adenocarcinoma↗

Validity of urinalysis and microscopy for detecting urinary tract infection in the emergency department.

This study assessed the validity of standard urinalysis, urinalysis for leucocyte esterase and nitrites, and urgent microscopy in the diagnosis of urinary tract infection (UTI) in 60 female patients with a triage diagnosis of UTI. There were 24 (40%) proven UTIs after culture. Simple urinalysis was sensitive for UTI (95.8%) but the positive predictive value was only 45.1%. The addition of leucocyte esterase and nitrite urinalysis testing did not improve the sensitivity, but if both of these were positive the positive predictive value improved to 100%. Urgent microscopy alone was sensitive (100%) but non-specific (38.9%). The specificity of the diagnosis improved to 94.4% for organism counts of >or=10/microl and to 88.9% for leucocyte counts of >or=50/microl. The negative predictive value of no detectable leucocytes on microscopy was 94.7%. Screening for UTI in the emergency department (ED) population is improved by the addition of leucocyte esterase and nitrite test. A positive urinalysis test for leucocytes and nitrites, or urinalysis positive at levels of >or=500 leucocytes or >or=5 g/l protein should confirm a clinical diagnosis of UTI. Urgent urine microscopy should be performed only if the above criteria are not met yet a minimum of one urinalysis result is positive.

Adult↗

Evaluation of the corneal effects of topical ophthalmic fluoroquinolones using in vivo confocal microscopy.

PURPOSE: To compare the effects of several fluoroquinolone antibiotics on the corneal epithelium and stroma using in vivo confocal microscopy. METHODS: Five antibiotic solutions were evaluated: 1) 0.3% ofloxacin (Oflox) solution with 0.005% benzalkonium chloride (BAC); 2) 0.3% gatifloxacin (Gati) solution with 0.005% BAC; 3) 0.3% ciprofloxacin (Cipro) solution with 0.006% BAC; 4) 0.5% levofloxacin (Levo) with 0.005% BAC; and 5) 0.5% moxifloxacin (Moxi) solution with no BAC. Preservative-free artificial tears (Tears) were used as a control. New Zealand white rabbits were used for this study (six per solution group). Ten days prior to exposure to any solution, central corneal epithelial thickness and stromal thickness were measured using in vivo confocal microscopy through focusing. Images of the superficial epithelium were also acquired. Both eyes of each rabbit then received one drop of the assigned solution six times the first day and then four times per day for 6 days. On day 7, in vivo confocal microscopy was repeated. RESULTS: A significant decrease in epithelial thickness was induced by 7 days of exposure to Levo, Gati, Oflox, and Cipro (P < 0.05, two-way repeated-measures ANOVA, Tukey test). Tears and Moxi, which do not contain BAC, did not induce significant changes in epithelial thickness. No significant changes in stromal thickness were detected (P = 0.266), and no keratocyte activation was observed for any of the solutions evaluated. CONCLUSION: We have previously used confocal microscopy to establish a correlation between epithelial thinning (due to superficial cell loss) and slight ocular irritation. The results of this study suggest that Moxi induces less damage to the corneal epithelium than other antibiotic solutions, perhaps because it does not contain BAC.

Animals↗

Confocal microscopy and corneal sensitivity in a patient with corneal manifestations of Tangier disease.

PURPOSE: Tangier disease is an autosomal recessive disorder in which cholesterol-rich lipids are deposited at various tissues of the body including the cornea. In this case report, the corneal changes in a patient with Tangier disease are described. METHODS: A 72-year-old patient who was diagnosed with Tangier disease 25 years before received a complete eye examination including confocal microscopy and Cochet-Bonnet esthesiometry. RESULTS: Slit-lamp biomicroscopy and confocal microscopy showed bilateral corneal opacifications caused by lipid accumulation. Confocal microscopy showed that pathologic changes in the cornea in Tangier disease are limited to the stroma. Neither a reduced corneal sensation nor lid abnormalities as previously described in Tangier disease were found. CONCLUSION: Confocal microscopy helps to identify corneal changes in the stroma caused by Tangier disease easily missed in a slit-lamp examination. The ocular manifestations of Tangier disease do not necessarily include a reduced corneal sensitivity and lid abnormalities.

Aged↗

Quantitative anatomical differences in central corneal thickness values determined with scanning-slit corneal topography and noncontact specular microscopy.

PURPOSE: This study was designed to analyze the differences in central corneal thickness values determined with noncontact specular microscopy and scanning-slit corneal topography. The measurements were performed on the same eye. METHODS: We analyzed the central corneal thickness values of 93 patients (n = 93) by means of noncontact specular microscopy (Topcon SP-2000P noncontact specular microscope, Topcon Corp., Tokyo, Japan) and scanning-slit corneal topography (Orbscan Topography System II, Orbscan Inc., Salt Lake City, UT). One experienced physician performed 3 consecutive central corneal thickness measurements with both devices. RESULTS: The central corneal thickness values obtained by means of Orbscan pachymetry were 17 +/- 2.7 (range, 12-24) microm greater. A significant correlation was observed between scanning-slit corneal topography and noncontact specular microscopy (Pearson correlation coefficient, r = 0.976; P < 0.001). CONCLUSIONS: Researchers should know of the existence of this difference between noncontact specular microscopy and Orbscan pachymetry when interpreting central corneal thickness values.

Adult↗

In vivo confocal microscopy of normal conjunctiva and conjunctivitis.

PURPOSE: To analyze the appearance of normal conjunctiva and conjunctival inflammation by in vivo confocal microscopy. METHODS: Conjunctiva of 15 normal patients and 21 patients with conjunctivitis including bacterial, papillary, follicular, granulomatous, and cicatrizing disease were analyzed by the Heidelberg retina tomograph (HRTII)/Rostock cornea modul (RCM). RESULTS: Scans of normal bulbar and tarsal conjunctiva corresponded well to the established anatomy except for a prominent, thickened epithelial basement membrane observed by in vivo microscopy. Presumed goblet cells were visible throughout the conjunctival epithelium. Adenoid structures and hair follicles were discernible in the tarsal conjunctiva in vivo. Conjunctival perfusion could be observed directly. Acute and chronic inflammatory cells, conjunctival papillary, and follicular reactions, as well as conjunctival cicatrization, could be discriminated. In a patient with conjunctival granuloma, in vivo confocal microscopy disclosed suture material inside the lesion. CONCLUSION: Confocal microscopy using near-infrared laser light is a useful new tool in the analysis of conjunctival tissue in vivo. It is a valuable aid in the differential diagnosis of conjunctival inflammation and thus may guide therapeutical decisions.

Adult↗

In vivo confocal microscopy of failing and functioning filtering blebs: Results and clinical correlations.

PURPOSE: To correlate clinical filtering bleb function with characteristics as detected by in vivo confocal microscopy. METHODS: In a case-matched cross-sectional study, 52 eyes of 48 patients were examined 1 day to 12.8 years after primary trabeculectomy (mean 375 d). The patients were examined clinically and by in vivo confocal microscopy (Rostock Cornea Module/Heidelberg Retina Tomograph II, Heidelberg Engineering, Inc, Heidelberg, Germany). Nine early and 17 late functioning blebs were pair-matched with malfunctioning blebs. Stromal fiber patterns, the number of intraepithelial and stromal cystic spaces, and the amount of cellular infiltrates were evaluated. RESULTS: Four stromal patterns (trabecular, reticular, corrugated, compacted) invisible to slit-lamp biomicroscopy could be distinguished by in vivo confocal microscopy. The trabecular pattern occurred only in functioning blebs, particularly early postoperatively. Intraepithelial cystic spaces were associated with functioning late blebs, whereas they were equally distributed in early blebs. In contrast, stromal cystic spaces indicate function in early blebs, whereas in late blebs the number of these cavities was similar in both groups. The density of intraepithelial and stromal round cells was higher in functioning late blebs compared with malfunctioning late blebs. CONCLUSIONS: In vivo confocal microscopy allows to assess filtering bleb structures that are invisible biomicroscopically. Some morphologic features detected by this technique seem to indicate filtering bleb function and time after surgery. The predictive value of these features deserves further clarification in a prospective longitudinal study.

Aged↗

Endoscopic confocal fluorescence microscopy of normal and tumor bearing rat bladder.

PURPOSE: We evaluated the possibility of performing endoscopic fiber-optic confocal microscopy in a rat bladder model and we distinguished different cell types. MATERIAL AND METHODS: Rhodamine 123 (Molecular Probes, Eugene, Oregon) (100 microM) was instilled for 30 minutes in 5 tumor bearing rat bladders (AY27). Five normal rats served as controls. A Cell-viziotrade mark confocal microscopy fiber was placed transurethrally in contact with normal or transformed bladder wall. Frozen sections were obtained from the same spots and subjected to conventional fluorescence microscopy and anatomical-pathological analysis. RESULTS: The different cells types present in rat epithelium (umbrella, intermediate and basal cells) could easily be identified with the Cell-viziotrade mark device due to their differences in morphology and fluorescence intensity. Individual AY-27 cells could not be demarcated due to the strong fluorescence signal but the entire tumor appeared as a brightly homogenous fluorescent blot surrounded by small inflammatory cells. CONCLUSIONS: We report the feasibility of endoscopic, in vivo, fiber-optic confocal microscopy in the rat bladder. We distinguished tumors from normal epithelium and visualized the different epithelial cell types in nontransformed rat bladder epithelium.

Animals↗

Pulsed and scanned carbon dioxide laser resurfacing 2 years after treatment: comparison by means of scanning electron microscopy.

Studies have reported short-term and long-term (1-year) findings for laser skin resurfacing. Two of the most popular systems used for this procedure, the continuous-wave Sharplan 40C SilkTouch system and the pulsed Coherent 5000C UltraPulse system with a computer pattern generator, were previously compared for a range of follow-up times up to 1 year, using light microscopy and transmission electron microscopy. This study analyzed the 2-year morphological differences using scanning electron microscopy. Tissue samples were obtained from 10 patients (age range, 50 to 72 years; skin types II and III) who had undergone laser resurfacing 2 years previously. One half of the face of each patient had been treated with the continuous-wave system and the other half with the pulsed system. The samples were subjected to scanning electron microscopy. On the continuous-wave-treated side, significantly better dermal collagen organization was observed at 2 years, with plump-appearing fibers that were closely knit to form a compact structure. On the side treated with the pulsed system, the collagen fibers in the papillary dermis were more loosely arranged and appeared drier. In both the continuous-wave-treated and pulsed-treated areas, the epidermis appeared healthy and exhibited some signs of age-related deterioration, with slightly flatter plaques and somewhat more flaking keratin on the pulsed-treated side. Probably because of the greater degree of residual thermal damage associated with the continuous-wave system, at 2 years after treatment there was more prolific synthesis and better orientation of collagen fibers, which were maintained for longer times, compared with the pulsed-treated specimens.

Aged↗

Double immunofluorescence microscopy: a method for localizing immune deposits in skin diseases associated with linear basement membrane zone immunofluorescence.

Direct immunofluorescence microscopy has shown that a linear pattern of immunoglobulin and/or complement deposition at the cutaneous basement membrane zone is a characteristic feature in a number of acquired bullous diseases and is occasionally observed in systemic lupus erythematosus. Immunoelectron microscopy has shown the linear pattern of immunofluorescence may be produced by immune deposits located either above the basal lamina (in the lamina lucida) or below the basal lamina (in the upper dermis). Distinguishing between these sites of immune reactant deposition may be of value in differential diagnosis. In this study we report a double immunofluorescent method by which skin biopsies with linear IgG immunofluorescence due to deposits above the basal lamina (bullous pemphigoid) could be distinguished from biopsies with deposits beneath the basal lamina (bullous systemic lupus erythematosus and epidermolysis bullosa acquisita). When skin sections were treated sequentially with rhodamine-labeled anti-human IgG followed by fluorescein-labeled antilamina lucida (pemphigoid) antibody and examined by fluorescence microscopy, the following results were obtained. In biopsies with IgG deposits in the lamina lucida, a single green fluorescent band was observed. In tissues with subbasal lamina deposits, either parallel and contiguous bands of green and yellow-orange fluorescence or a single band of yellow-orange fluorescence was observed. The method is simpler, quicker, and less expensive than immunoelectron microscopy and should be a useful technique for evaluating skin diseases with linear immunofluorescence at the basement membrane zone.

Basement Membrane↗