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Objectives: Cryptococcal meningoencephalitis is the most common fungal infection of the central nervous system diagnosed by cerebrospinal fluid cytology (CSF) studies. Existing literature suggests that routine CSF cytomorphologic evaluations are exquisitely specific; however, less is known about their sensitivity., Methods: An electronic record review of the cytopathology and microbiology files was conducted for the 21-year interval from January 1, 1995, through December 31, 2015., Results: In 21 years, 12,584 CSF samples were processed in the laboratory. Of these, 24 (0.2%) were reported positive for cryptococcal organisms by light microscopy, and 129 CSF fungal cultures were positive for Cryptococcus species. All cotested specimens with positive cytology results were positive on culture (15 specimens, 100% specificity). Twenty-four samples with positive culture results were negative by CSF cytology (sensitivity 39%)., Conclusions: When culture is used as a gold standard, CSF cytology is 100% specific and 39% sensitive, with a positive predictive value of 100% and a negative predictive value of 99.8%.

Objectives: Clinical Laboratory Improvement Amendments of 1988 (CLIA '88) regulations specify that at least 10% of negative Papanicolaou (Pap) slides be rescreened as a quality control (QC) measure. With incorporation of human papillomavirus (HPV) DNA testing into screening guidelines for women aged 30 years or older, a population of patients exists who are HPV positive as well as negative for intraepithelial lesion or malignancy (NILM)., Methods: In this 9-month retrospective review with follow-up, 26,501 women 30 years of age and older underwent liquid-based Pap screening with concomitant high-risk HPV DNA testing at CellNetix Pathology and Laboratories, Seattle, WA. Of these women, 1,096 (4.1%) were originally interpreted by cytotechnologists as NILM with HPV DNA positivity., Results: On rescreening, 13.9% (152/1,096) of patients were upgraded to atypical squamous cells and higher, with 2.8% being upgraded to low-grade squamous intraepithelial lesion (LSIL) and higher. Historical routine QC measures from the same period showed that 0.3% of cases were upgraded to LSIL and higher, representing a statistically significant increase in the detection of cases with LSIL and higher (χ(2) two-tailed P < .0001)., Conclusions: Focused rescreening of this enriched subpopulation of patients who are NILM and high-risk HPV DNA positive enhances QC. An inherent potential bias in study design is recognized because results of DNA testing were, by definition, known at the time of rescreening result interpretations.

The American Society for Colposcopy and Cervical Pathology (ASCCP) has proposed high-risk human papillomavirus (HPV) testing as the "preferred" triage for women with atypical squamous cells of undetermined significance. We studied 401 atypical squamous cells of undetermined significance liquid-based cervicovaginal cytology split samples for HPV by chromogenic in situ hybridization (CISH) and by Hybrid Capture (HC) II (Digene, Gaithersburg, MD); 202 underwent HC II followed by CISH, and 199 underwent CISH followed by HC II. Of 401 vials, 101 (25.2%) were positive for HPV by 1 or more methods. HC II labeled 83 of 401 (20.7%) samples as positive, while 38 of 401 (9.5%) were positive by CISH. Positive attributes of CISH include the provision of a cytomorphologic link in assessing HPV positivity and comparative ease of use in laboratories without trained molecular diagnosticians. Greater efficacy and quantitative design are advantages of HC II. Comparing data by sequence of testing showed a lower likelihood of positive test results on the second ancillary test than on the first ancillary test, regardless of age or testing method (odds ratio, second/first = 0.58; P = .003). This finding suggests that liquid-based cervicovaginal cytology samples are not homogeneous throughout. Correlative studies with histology and polymerase chain reaction may clarify predictive values for both methods.

Follow-up of Papanicolaou (Pap) tests diagnosed as atypical squamous cells of undetermined significance (ASCUS) or atypical glandular cells of undetermined significance (AGUS) by a cytotechnologist and downgraded to benign by a pathologist has not been measured. Squamous intraepithelial lesion (SIL) follow-up rates were obtained for Pap tests diagnosed as ASCUS (288) or AGUS (94) and downgraded to benign and for Pap tests diagnosed as repair (231). Statistically significant associations were seen between 7 cytotechnologists and between 7 pathologists and ASCUS, AGUS, downgraded ASCUS, and downgraded AGUS rates. The percentage of downgraded ASCUS cases compared with all ASCUS cases per pathologist ranged from 4.8% to 43.7%. Statistically significant associations between pathologists and SIL follow-up rates for downgraded ASCUS diagnoses were seen. The SIL follow-up rate for repair (7.9%) was similar to that for a downgraded ASCUS (11.0%) or AGUS (7.3%). The parameters of downgraded ASCU and AGUS Pap test interpretations are good quality indicators of individual performance and overall laboratory quality.

The use of cytohistologic discrepancies to investigate and reduce error seldom is studied. All gynecologic discrepancies (n = 283; 0.87% and 7.37% of all cytologic and histologic cases, respectively) and nongynecologic discrepancies (n = 146; 2.26% and 0.44% of all cytologic and histologic cases, respectively) for 26 months were classified as sampling or interpretive. Specimen type and pathologist discrepancy percentages, effect of discrepancies on patient outcome, and interobserver agreement of discrepancies were evaluated. Discrepancies were interpretive in 67% and 34% of gynecologic and nongynecologic cases, respectively. Statistically significant associations were seen between individual pathologist and discrepancy percentages. Breast (1.2%) and bronchial (0.8%) cytologic diagnoses had the highest discrepancy percentages. The kappa scores ranged from 0.02 to 0.45 for pairwise agreement of discrepant cases. Of nongynecologic interpretive discrepancies available for review, 63% (27/43) and 14% (6/43) were of no or minor clinical significance, respectively. Cytohistologic correlation is a useful tool to monitor performance and to identify specimen types prone to error.

One blinded observer (C.D.S.) retrospectively reviewed 76 previously diagnosed and biopsy-confirmed malignant bronchial brush and wash specimens, 46 non-small cell and 30 small cell carcinomas, obtained from 55 patients. Each case was scored for the presence or absence of 36 standard criteria (architectural, cytoplasmic, and nuclear). Logistic regression analysis was used to determine which criteria were most useful for separating small cell from non-small cell lesions. Although no single criterion displayed 100% sensitivity and specificity for small cell cancer, univariate statistical analysis indicated that 3 individual criteria (nuclear molding, finely granular or "salt and pepper" chromatin, and scant delicate cytoplasm) were more than 90% sensitive and specific in cases of small cell carcinoma. The presence of nuclear molding alone provided the best fit for the logistic regression model. When nuclear molding was present, the odds of a small cell diagnosis increased more than 300-fold. Nuclear molding, finely granular or salt and pepper chromatin, and scant, delicate cytoplasm are the 3 most sensitive and specific cytomorphologic features traditionally used to separate small cell from non-small cell carcinoma. Nuclear molding alone represents the most significant cytomorphologic feature for distinguishing between these malignant lesions.

Enriched broth medium is routinely used as a supplement for agar plate culture of cerebrospinal fluid (CSF). To assess the clinical utility of broth cultures, 151 consecutive CSF bacterial and fungal isolates obtained from 91 patients were retrospectively reviewed for the effect of results on treatment. Treatment decisions associated with individual CSF specimens for which isolates were recovered from thioglycollate broth only were compared with the treatment decisions associated with CSF specimens for which isolates were recovered by agar plate culture. Treatment was defined as initiation of or change in antimicrobial therapy based on the reporting of CSF culture isolates. Thirty-six (24%) of the 151 isolates were recovered in broth only. Three (8%) of these 36 isolates (from 34 patients) resulted in treatment with antimicrobial agents; however, 2 of the 3 treated isolates (Candida tropicalis, Proteus mirabilis) were recovered from a second CSF specimen in agar plate culture within 24 hours. Thus, only a single isolate (3%; Staphylococcus epidermidis) was treated based solely on a positive broth culture result. In contrast, 60 (52%) of the 115 isolates recovered in agar plate culture from 23 (40%) of 57 patients were treated (staphylococci, 28; gram-negative bacilli, 14; Cryptococcus neoformans, 10; Streptococcus pneumoniae, 3; Streptococcus sanguis, 1; other, 4). We conclude that treatment with antimicrobial agents based on isolates recovered from CSF specimens in broth culture alone is infrequent and infer from the data that the use of CSF broth cultures contributes little to treatment decisions.