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PubMed1999

An overhead specimen handling system for variable workloads.

This unique overhead specimen handling system requires virtually no floor space and only a minimal amount of bench space. It uses state-of-the-art conveyors suspended near the ceiling to transport, log-in and sort blood specimens in standard specimen containers. Specimens placed into the system at bench-level bins are automatically singulated and loaded onto cleated conveyors and lifted to the main conveyor belt near the ceiling. The barcoded labels are then read as the containers are rotated under an optical scanner. The specimens are then diverted to the appropriate branch conveyor and lowered back to the bench level by cleated conveyors. The specimen handling system is rapid and accurate, requires no special containers, allows laboratorians to move unimpeded below it, and is inexpensive by automation standards. Studies show no adverse effect upon the specimens.

Automation↗

PubMed2003

The Cobas Amplicor MTB test for detection of Mycobacterium tuberculosis complex from respiratory and non-respiratory clinical specimens.

The Cobas Amplicor MTB test is a polymerase chain reaction (PCR) technique commonly used for direct detection of Mycobacterium tuberculosis in clinical samples. This assay is only validated for respiratory specimens, but many physicians also request PCR analyses for non-respiratory ones. 877 respiratory and 564 non-respiratory specimens were analysed by this test. Using culture results as standard, the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the PCR were, respectively, 97.9%, 100%, 100% and 94.4% for smear-positive respiratory specimens, 68.8%, 99.2%, 87.5% and 97.5% for smear-negative respiratory samples, 57.8%, 98.6%, 78.8% and 96.4% for all non-respiratory specimens, and 42.4%, 98.6%, 66.7% and 96.4% for smear-negative non-respiratory specimens. 154 cerebrospinal fluid samples were analysed and the sensitivity, specificity, PPV and NPV were 55.6%, 97.2%, 55.6% and 97.2%, respectively. These results indicate that the Cobas Amplicor MTB test enables detection of tuberculosis in respiratory specimens, but does not perform well enough in non-respiratory specimens. The method fails particularly in cases where a reliable and rapid test is urgently needed, e.g. in tuberculous meningitis.

Bacteriological Techniques↗

PubMed1998

Acceptability of low-volume, induced sputum specimens for diagnosis of Pneumocystis carinii pneumonia.

Two milliliters of induced sputum is the minimum volume recommended for microscopic examination for Pneumocystis carinii by direct fluorescent antibody (DFA) stain. Many specimens received in our laboratory do not meet this criterion. Rejection of these inadequate specimens increases cost and discomfort to the patient because additional specimens must be obtained. To determine whether volumes less than 2 mL were acceptable for microscopic analysis, we examined 177 consecutive induced sputum specimens submitted for P. carinii DFA stain. Eighty-four (47.4%) specimens were less (0.5-1.9 mL) than the 2-mL volume recommended by the manufacturer. Overall, 33 specimens were positive. The positivity rates for specimens 2 mL or more and less than 2 mL were 18% and 19%, respectively. Induced sputum volumes between 0.5 and 2 mL may be acceptable for DFA examination.

Fluorescent Antibody Technique, Direct↗

PubMed1980

A pitfall in hemoglobin electrophoresis. Artefactual minor unstable hemoglobin results from improper specimen handling.

Blood specimens are commonly mailed for the purpose of hemoglobin studies, such as identification of abnormal hemoglobins and measurement of hemoglobins A2 and F. In a period of a few months, the author examined eight specimens sent from a referring laboratory, in which cellulose acetate electrophoresis (p H 8.6) revealed a discrete minor band in a position approximately midway between the positions of hemoglobins A and S. For each specimen, tests for hemoglobin instability were positive. In one specimen, marked methemoglobinemia and sulfhemoglobinemia were also demonstrated. Further studies of fresh specimens obtained from the same subjects failed to demonstrate any hemoglobinopathy. The abnormal band in the original eight specimens was an artefact resulting from improper specimen handling--that is, unduly long transit times without refrigeration. The aftefactual band had electrophoretic mobility identical to that of methemoglobin derived from hemoglobin A.

Aged↗

PubMed1980

Evaluation of a pneumatic-tube system for delivery of blood specimens to the blood bank.

This study evaluated the suitability of delivering patient blood specimens to the blood bank by a hospital pneumatic-tube system. No significant discrepancies were found between duplicate pneumatic-tube and hand-carried specimens in ABO and Rh typing, Du and direct Coombs' testing, rouleaux formation, and antibody screening and identification. There were no significant differences in titers or scores of unexpected erythrocytic antibodies in duplicate pneumatic-tube and hand-carried specimens. No significant differences in antibody strength were detected between specimens from partially-filled and nearly full clot tubes delivered by pneumatic-tube. Our pneumatic-tube system may be safely used to transport patient blood specimens for routine type and crossmatch. Slight hemolysis in some pneumatic-tube specimens makes our pneumatic-tube system unsuitable for transporting blood specimens collected for evaluation of transfusion reactions.

Antibodies↗

PubMed2000

Morphine-3-D glucuronide stability in postmortem specimens exposed to bacterial enzymatic hydrolysis.

Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths.

Adolescent↗

PubMed1999

How adequate is adequate for the collection of endocervical specimens for Chlamydia trachomatis testing?

BACKGROUND: Endocervical specimen adequacy has been assessed by subjective criteria that are based on arbitrarily chosen thresholds for the presence of target cells observed on microscopic slide examinations. GOAL OF THIS STUDY: To assess the relationship of chlamydia test positivity to specimen adequacy with the use of a semi-quantitative cytologic staining method for assessing endocervical specimen collection cellularity. STUDY DESIGN: Endocervical specimens for chlamydia testing (PACE 2, GenProbe, San Diego, CA) and for a slide cytologic examination (n = 3,500) were collected in parallel. A semi-quantitative cytologic examination to determine a specimen adequacy (SA) score was performed for every chlamydia-positive result (n = 163) and approximately every fifth negative result (n = 626). The Chi-square test for linear trends was used to assess the relationship between SA scores and chlamydia positivity. The median SA scores for chlamydia-positive and negative slides were compared. RESULTS: The median SA scores for chlamydia-positive and -negative slides were 27 and 20, respectively (P < 0.001). Chlamydia positivity rates increased with increasing specimen adequacy scores (0-9, 2.7%; 10-19, 15.1%; 20-29, 24.8%; and 30-45, 31.3%; Chi-square for linear trend: P < 0.001). CONCLUSION: These results demonstrate a linear relationship between the numbers of cells observed on an endocervical smear and chlamydia positivity rather than the threshold concept in practice. The semiquantitative cytologic technique offers an objective method for further evaluating specimen adequacy for Chlamydia trachomatis testing.

Cervix Uteri↗

PubMed1997

Rapid detection of mycobacteria in clinical specimens by using the automated BACTEC 9000 MB system and comparison with radiometric and solid-culture systems.

Recovery rates of acid-fast bacilli (AFB) and the mean time to their detection from clinical specimens were determined by using the fluorescent BACTEC 9000 MB system. Data were compared to those assessed by the radiometric BACTEC 460 system and by cultivation on solid media. A total of 3,095 specimens were processed with N-acetyl-L-cysteine-NaOH by two laboratories. The contamination rates for the BACTEC 9000 MB system were 6.8% (center 1) and 9.8% (center 2). A total of 451 mycobacterial isolates were detected (Mycobacterium tuberculosis complex, n = 296; nontuberculous mycobacteria [NTM], n = 155). These isolates originated from 94 (20.8%) smear-positive and 357 (79.2%) smear-negative specimens. The BACTEC 9000 MB system was significantly better than solid media (P < 0.05) in detecting AFB, but it was less efficient than the radiometric system (P < 0.01). The BACTEC 9000 MB system plus solid media (combination A) recovered 393 (87.1%) of the isolates, while the BACTEC 460 system plus solid media (combination B) detected 430 (95.3%) of all AFB isolates. Between combination A and B there was no statistically significant difference for the detection of isolates from smear-positive specimens (P > 0.05), in contrast to the recovery of AFB from smear-negative specimens for M. tuberculosis complex, P < 0.05; for NTM, P < 0.01). The mean time to detection of M. tuberculosis complex was 12.2 days for smear-positive specimens and 18.1 days for smear-negative specimens with the BACTEC 9000 MB system; 9.3 and 15.6 days, respectively, with the BACTEC 460 system; and 21.2 and 28.4 days, respectively, with solid media. For NTM, the average detection times were 15.1, 17.3, and 31.3 days by the three methods, respectively. In conclusion, the BACTEC 9000 MB system is a rapid, less labor-intensive detection system which allows for higher levels of recovery of AFB than solid media. There is no risk of cross contamination, which is known to be the case for the BACTEC 460 system, and data management is greatly facilitated. As a whole, however, the BACTEC 9000 MB system should only be used in conjunction with solid media.

Bacteriological Techniques↗

PubMed1998

Novel method for processing respiratory specimens for detection of mycobacteria by using C18-carboxypropylbetaine: blinded study.

A novel method for processing respiratory specimens to improve culture and acid-fast staining of mycobacteria is introduced. This new method utilized N,N-dimethyl-N-(n-octadecyl)-N-(3-carboxypropyl)ammonium inner salt (Chemical Abstract Service no. 78195-27-4), also known as C18-carboxypropylbetaine (CB-18). In a blinded, five-center study, CB-18-based processing was compared to the standard method combining NALC and NaOH (NALC/NaOH). A total of 573 respiratory specimens were tested. Individual specimens were split approximately equally; the host institutions processed half of each specimen by the NALC/NaOH method, while the other half was processed with CB-18 at Quest Diagnostics--Baltimore. A total of 106 specimens were culture positive for acid-fast bacilli (AFB). Replacement of the primary decontamination agent with CB-18 caused changes in all diagnostic parameters. Aggregate culture sensitivity improved by approximately 43% (P < 0.01), and smear sensitivity improved by approximately 58% (P < 0.01). The sensitivity of smear relative to that of M. tuberculosis isolates exceeded 93% (P < 0.01) when specimens were processed with CB-18. The average times to a positive result were reduced by 7.3 days in liquid culture (P < 0.01) and 5.3 days on solid media (P < 0.05); however, the CB-18 method had a 20.8% contamination rate in liquid culture versus a rate of approximately 7.5% with NALC/NaOH processing. There were also unusual reductions in liquid culture sensitivity and smear specificity among CB-18-processed specimens. The characteristics of the latter parameters suggested that refinement of the CB-18 processing method should allow further improvements in culture sensitivity. This study showed that the CB-18 method has the potential to improve both smear and culture detection for these important human pathogens.

Bacteriological Techniques↗

PubMed2002

Detection of human papillomavirus DNA in urine specimens from human immunodeficiency virus-positive women.

Human immunodeficiency virus (HIV)-positive women may represent one of the fastest-growing populations at risk for acquiring cervical cancer and thus require frequent screening. The purpose of the present studies was to validate a PCR-based urine assay by comparing detection and genotyping of human papillomavirus (HPV) DNA in urine samples and matching cervical swab specimens of HIV-positive women. Despite a difference in amplifiability, the prevalence of any HPV genotype (58% for the cervical swab specimens and 48% for the urine specimens) was not significantly different in this population. The levels of concordance were 70, 71, and 78% for detection of any HPV type, any high-risk HPV type, or any low-risk HPV type in the two specimen types, respectively. While instances of discordant detection were greater for the cervical swab specimens than for the urine specimens, this was not statistically significant. The distributions of HPV genotypes were similar in the cervix and the urine for the majority of types examined. Importantly, detection of HPV DNA in urine was associated with an abnormal Papanicolaou smear to the same extent that detection of HPV DNA in a cervical swab specimen was. These data provide preliminary support for the proposal to use urine testing as a primary or secondary screening tool for cervical cancer in HIV-positive women or as an epidemiological tool. Additional studies with larger sample sizes must be conducted in order to further verify these findings.

Adult↗

PubMed2006

Comparison of physician- and self-collected genital specimens for detection of human papillomavirus in men.

There is currently no consensus regarding the most appropriate methods of sampling for the detection of genital human papillomavirus (HPV) in men. We employed a recently developed collection method involving abrasion and moistened swabbing of the genital skin surface for the detection of HPV in a cohort of 136 university-affiliated males in Hawaii. Genital specimens collected by physicians using this method were compared with self-collected specimens from the same individuals obtained 24 h later. Self-collected specimens yielded a greater proportion of sufficient specimens than physician-collected specimens. HPV detection was comparable in physician- and self-collected specimens; detection was highest in the penile shaft (51.2% and 51.5%, respectively, P = 0.96), followed by the scrotum (41.2% and 46.2%, P = 0.43), the glans/coronal sulcus (31.9% and 33.1%, P = 0.84), and the foreskin (33.3% and 28.6%, P = 0.74). Site-specific agreement in HPV detection between paired physician- and self-collected samples ranged from 67.2% (kappa = 0.34) for the penile shaft to 95.0% (kappa = 0.89) for the foreskin. There was a high degree of concordance in HPV genotypes in HPV-positive pairs. The most common type was HPV type 84, which comprised approximately 15% of the specimens. The emery paper-swab method offers an efficient sampling method for genital HPV DNA detection in men that could be used both within and outside of the clinical setting.

Adolescent↗

PubMed1988

Breast specimen radiography: evaluation of a compression device.

The irregular shape and uneven tissue thickness of excised breast specimens makes radiographic evaluation difficult, especially when calcifications are not present. Xeroradiographs before and after compression of 20 separate excised breast specimens were compared, and 17 of the same specimens were compared after compression combined with immersion in water. Specimen compression improved visibility of the lesion on average in 88% of cases, and visibility was equal in 12%. Combined compression/immersion further improved visibility of the lesion on average in 37% of cases. More significantly, evaluation of the compressed specimen led to a change in interpretation of the radiographs in 45% of cases. Compression of the specimen in specimen radiography is recommended in all cases in which pre-biopsy localization is performed.

Biopsy↗

PubMed1991

Evaluation of the float sign for determining adequacy of specimens obtained with transbronchial biopsy.

This study prospectively evaluated the alveolar content of transbronchial biopsy specimens based on whether or not they floated in formalin. One hundred biopsy specimens were obtained from 18 patients. Specimens with any alveoli were significantly more likely to float (45 of 61, 74%) than those with no alveolar tissue (15 of 39, 39%; p less than 0.001). The majority of diagnostic specimens were obtained in eight patients with sarcoidosis, where 47 biopsies were obtained. Fourteen of 19 specimens (74%) with noncaseating granulomas floated, whereas only 11 of 28 (39%; p less than 0.05) nondiagnostic specimens floated. The results of this study suggest that this simple bedside observation may serve to determine the adequacy of transbronchial biopsy specimens, particularly in sarcoidosis.

Biopsy↗

PubMed2006

The effect of specimen hemolysis on coagulation test results.

Hemolyzed specimens are rejected for coagulation testing based on concerns of artifactual interference. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and selected factor assay test results for consecutive pairs of hemolyzed and subsequently recollected (mean, 72 minutes later) nonhemolyzed patient specimens were compared. Specimens from healthy human subjects were subjected to mechanically induced hemolysis, and PT and aPTT results compared with concurrently drawn nonhemolyzed control samples. In 50 paired patient specimens, there were statistically significant differences in PT (15.8 +/- 8.4 vs 16.3 +/- 8.7 seconds, P < .01) and aPTT (31.6 +/- 18 vs 32.5 +/- 19 seconds, P < .01) between hemolyzed and nonhemolyzed specimens, respectively. Specimens from healthy subjects showed no difference in PT and a minor difference in aPTT. A policy of rejecting hemolyzed specimens for coagulation tests should be revisited because the observed difference, when present, is unlikely to be considered clinically meaningful.

Analysis of Variance↗

PubMed2004

Cost-effectiveness of immediate specimen adequacy assessment of thyroid fine-needle aspirations.

Pathologists and cytotechnologists often provide immediate specimen adequacy evaluation of thyroid fine-needle aspirations (FNAs) to ensure that diagnostic material is obtained. We assessed the cost-effectiveness of this practice. All patients who had a thyroid FNA specimen accessioned at the Beth Israel Deaconess Medical Center, Boston, MA, during a 6-month period were included and divided into 2 groups: (1) with or (2) without immediate adequacy assessment. Specimen adequacy from each group was compared. The time spent to perform the adequacy assessment was recorded. Compared with group 2, group 1 had more specimens with diagnostic cellular material (67.2% vs 47.0%) and fewer specimens with suboptimal (23.3% vs 38.1%) or nondiagnostic cellular material (9.5% vs 14.9%) (P = .002). At the time of adequacy assessment, 98% (60/61) of the adequate specimens were obtained with 3 or fewer passes. The improved rate of diagnostic material was achieved at a cost of 220 minutes of cytologists' time per additional diagnostic specimen compared with group 2. It may be most cost-effective to routinely obtain 3 passes and to perform immediate adequacy assessment under special circumstances such as repeated procedures.

Biopsy, Fine-Needle↗

PubMed1996

Cost-effectiveness of collecting routine cytologic specimens during fiberoptic bronchoscopy for endoscopically visible lung tumor.

STUDY OBJECTIVE: Fiberoptic bronchoscopy is the most common modality used to diagnose endobronchial carcinoma. Collection of brushing and washing specimens for cytology is common during bronchoscopy for endobronchial abnormality, but it is unknown if collection of these specimens is cost-effective. DESIGN: Retrospective review of a computerized database with cost-effectiveness analysis. SETTING: Tertiary care medical center. PATIENTS: Two hundred one patients undergoing bronchoscopy for endobronchial lung tumor. INTERVENTION: All patients in the study underwent fiberoptic bronchoscopy that included forceps biopsies, washings, and brushings. In addition to analyzing the sensitivity of forceps-biopsy, washings, and brushings at diagnosing malignancy, we analyzed the cost-effectiveness of three potential specimen collection strategies. These strategies were (1) collection of both washings and brushings in addition to forceps biopsy specimen, (2) collection of either washings or brushings in addition to forceps biopsy specimen, and (3) collection of forceps biopsy specimen only. MEASUREMENTS AND RESULTS: The sensitivity of bronchoscopy, including biopsy, washing, and brushing is 85.3% (95% confidence interval [CI], 80.1 to 90.5%). The sensitivity of forceps biopsy is 80.8% (95% CI, 75.0 to 86.6%). The addition of washings and brushings increases the sensitivity of bronchoscopy from 80.8 to 85.3% (McNemar's p = 0.01). Cost-effectiveness analysis reveals that forceps biopsy plus washing or brushing has a marginal cost-effectiveness ratio of $308 per reduced-quality day avoided compared with forceps alone. Adding an additional cytology specimen has a marginal cost-effectiveness ratio of $5,500 per reduced-quality day avoided. CONCLUSIONS: There is a modest but definite increase in the sensitivity of bronchoscopy in diagnosing endobronchial cancer with the addition of washings and brushings for cytology. Cost-effectiveness analysis reveals that collection of either washings or brushings is probably the best strategy.

Bronchoscopy↗

PubMed2006

Quality improvement to decrease specimen mislabeling in transfusion medicine.

CONTEXT: Proper specimen identification and labeling is a critical preanalytic step in pretransfusion compatibility testing. OBJECTIVE: To gather baseline data for specimen mislabeling, specifically targeting major mislabeling events, and to design and implement a plan of corrective action. DESIGN: All mislabeled specimens received by the transfusion service for a type and screen were recorded and classified into minor and major mislabeling categories. Major mislabeling events were tracked by origin of the specimen. Locations with a high proportion of major mislabeling were given timely feedback (within 1 week) of the events as they arose. SETTING: A university hospital. MAIN OUTCOME MEASURES: The incidence of major mislabeling. RESULTS: The incidence of mislabeling in the transfusion service was 0.5% (243/49 955) during 21 months of data collection. Of these mislabeling events, 47% were classified as major events (unlabeled, mismatched specimen/ requisition, ABO/Rh result on current specimen not matching historical record on file). The emergency department accounted for a high proportion of these major mislabeling events. After the intervention of providing weekly feedback to emergency department staff, their contribution to major mislabeling fell from 47% in 1 year (23/49) to 14% (4/29) in the subsequent 3 quarters. CONCLUSIONS: Collecting and trending data on mislabeled samples with timely feedback to patient care areas can change phlebotomy practice and reduce specimen mislabeling.

Blood Group Incompatibility↗

PubMed2006

Key issues in handling and reporting radical prostatectomy specimens.

CONTEXT: Patients with prostatic adenocarcinoma commonly undergo radical prostatectomy, and it is often difficult and time consuming to handle the resulting specimens and to report the findings. Pathologic information derived from the radical prostatectomy specimen is used for selecting adjuvant therapy, such as radiotherapy and hormone therapy, and for determining a patient's prognosis. The prostate specimen must be handled in a systematic fashion to derive the appropriate prognostic parameters. OBJECTIVE: To review the prognostic factors of relevance in classifying radical prostatectomy specimens, using the College of American Pathologists categorization system, including a detailed survey of the morphologic-based factors but excluding other factors such as DNA ploidy and novel phenotypic and genotypic markers. CONCLUSIONS: Gleason score, pathologic stage, and margin status are considered category 1 prognostic factors, which are of proven prognostic significance and are useful in patient management. Factors such as tumor volume (intraglandular extent) and tumor subtype are considered category 2 prognostic factors, which show significant promise but require validation in multivariate analysis. Lymphovascular space invasion is a promising category 3 prognostic factor that needs additional study. Perineural invasion is an almost ubiquitous finding in radical prostatectomy specimens and is considered a category 3 prognostic factor. After prognostic factors have been analyzed at the histologic level, it is critical to report the findings in a clear and unambiguous fashion. The synoptic style of reporting is ideal for describing complex cancer resection specimens. A synoptic report based on an evidence-based checklist, such as the one developed by the College of American Pathologists, effectively communicates complex cancer-related data, such as radical prostatectomy specimen findings. This information is used not only for individual case management with respect to treatment and prognostication but also for purposes such as education, research, quality monitoring, and system planning.

Adenocarcinoma↗