Hospital outbreak of Carbapenem-resistant acinetobacter baumannii in the context of local facility transmission.

Carbapenem-resistant Acinetobacter baumannii are of increasing concern in the health care setting. We describe a cluster of 9 cases in hospitalized patients over a 3-month period that reflected ongoing community transmission from high-risk facilities. Robust surveillance and knowledge of local epidemiology are critical to mitigating onward transmission in the health care setting.

Does the ThinPrep Imaging System increase the detection of high-risk HPV-positive ASC-US and AGUS? The Women and Infants Hospital experience with over 200,000 cervical cytology cases.

BACKGROUND: Published reports have demonstrated that introduction of the ThinPrep Imaging System (Imager) to the cytology screening services has increased the detection rate of high-grade squamous intraepithelial lesions (HSILs). In accordance with recent clinical treatment guidelines, patients with atypical squamous or glandular cells of undetermined significance (ASC-US or AGUS) are often tested for high-risk HPV infection using the Hybrid Capture HPV DNA test. We took the opportunity to investigate whether the Imager had resulted in any significant differences in our diagnostic categories, as well as whether the Imager increased the detection of high-risk HPV-DNA-positive (HRHPV+) ASC-US or AGUS. MATERIALS AND METHODS: Cytology cases with the diagnosis of ASC-US and AGUS were retrieved from the archival files of our institution during periods of 11 months prior to and 11 months after the introduction of the Imager. The total number of cases in each category was correlated with results of reflex high-risk HPV DNA testing when the latter were available. All AGUS diagnoses were correlated with subsequent biopsy follow-up. Statistical analyses were performed using the chi-Square test with Yate's Correction and Fisher's Exact test. RESULTS: A total of 108,371 and 104,555 of ThinPrep Pap Test (TPPT) cases were reviewed during 11 months pre- and post-imager introduction. The ASC-US rate was 5.4% in the pre-Imager and 5.3% in the post-Imager period. The HPV reflex test was 38% and 34% positive respectively in the pre- and post-Imager period (P>0.124). Similarly, 0.14% and 0.12% AGUS were found in the pre- and post-Imager period. The positive HPV reflex test was 14% versus 23% (P = 0.1690). The abnormal biopsy follow-up rate in the AGUS category was increased from 20.9% in the pre-Imager period to 31% in the post-Imager period (P = 0.1471). The ASCUS/SIL ratios were 1.9 and 1.6 respectively. CONCLUSIONS: The ASC-US and AGUS rates did not change statistically before and after the introduction of the Imager in our cytology laboratory. Although use of the Imager did not increase detection of HPV+ ASC-US, it did appear to increase the detection rate of HPV+ AGUS and subsequent abnormal biopsy follow-up rates in all categories. However, the increase in the detection rate did not reach the point of statistical significance.

ASC:SIL ratio following implementation of the 2001 Bethesda System.

The 2001 Bethesda system (TBS 2001) eliminated the "satisfactory but limited by" category, benign cellular changes (BCC), and the designations "favor benign" (ASC-B) and "favor low grade" (ASC-L) for atypical squamous cells. We compared the unsatisfactory rate and atypical squamous cells:squamous intraepithelial lesions (ASC:SIL) ratio pre- and postimplementation of TBS 2001 to see if there was an increase in unsatisfactory specimens, ASC rate, and altered ASC:SIL ratio. Pap Tests (569,726) reviewed at the Cytopathology Laboratory of Women and Infants Hospital from 1998-2002 were included. TBS 1991 terminology was used through December 31, 2001. Conversion to TBS 2001 took place on January 1, 2002. The average ASC:SIL ratios pre- and postimplementation of TBS 2001 were 1.52:1 and 1.42:1, respectively. The rates of unsatisfactory specimens and ASC remained unchanged. Conversion to TBS 2001 did not adversely affect the ASC:SIL ratio or the detection rates of abnormalities of Pap tests.

Utility of ProExC and IMP3 immunocytochemical staining in atypical glandular cells of undetermined significance in liquid-based cervical cytology.

The diagnosis of atypical glandular cells of undetermined significance (AGUS) in liquid-based cervical cytology specimens shows significant underlying pathology in only 30% of cases, while the remaining cases are found to be benign (reactive, reparative/metaplastic). Previous studies have reported positive ProExC and IMP3 staining in neoplastic glandular lesions of the uterine cervix and corpus. We present our experience with the utility of these markers in the evaluation of AGUS cases in liquid-based cervical cytology. The case cohort included 34 cases diagnosed as AGUS. ProExC and IMP3 immunocytochemical (ICC) stains were performed on ThinPrep® slides and the results correlated with subsequent biopsy findings. Positive expression was classified as strong diffuse nuclear immunostaining for ProExC and granular cytoplasmic for IMP3. The presence of AGUS cells on the ICC stained slides was confirmed in all cases. IMP3 was positive in 80% of glandular neoplasms and negative in 93% non-glandular lesions/cases negative for squamous intraepithelial lesion (SIL). ProExC was positive in 60% of glandular neoplasms and negative in 83% non-glandular lesions/cases negative for SIL. When used as a panel (ProExC + IMP3), at least one stain was positive in 100% of glandular neoplasm cases and they were both negative in 83% of non-glandular lesions/cases negative for SIL. Based on this study, both ProExC and IMP3, when used as an immuno panel, can predict the presence of glandular lesions on subsequent biopsies and can serve as an aid in the diagnosis and management of AGUS cases.

Utility of the Thin Prep Imaging System® in the detection of squamous intraepithelial abnormalities on retrospective evaluation: can we trust the imager?

Prospective studies analyzing the ThinPrep Imaging System (TIS) have demonstrated a significant decrease in screening time and detection rates comparable or better than manual screening. We retrospectively analyzed the accuracy of the TIS in detecting cervical abnormalities. Our study included all new HSIL diagnoses in 2007 with previous negative (NIL) pap tests screened with TIS. The original 22 fields of view (FOV) were reviewed by 2 blinded screeners followed by manual screening of all slides. Any ASC-US or above was considered "abnormal." Of a total of 111,080 pap tests performed in 2007, 180 were reported as HSIL. Of these, 45 cases had a previous NIL pap diagnosed within the last year, screened with TIS. Following re-examination of the NIL pap, 31 diagnoses remained unchanged and 9 were reclassified as abnormal on the basis of cells present within the original FOV. When manually reviewed, all nine cases were confirmed as abnormal. Four cases were reclassified as abnormal on the basis of the manual screen (abnormal cells absent in the FOV). The sensitivity of TIS for the detection of abnormality was 99.95% (false-negative rate FNR: 0.05%) and the sensitivity for detection of HSIL was 99.07% (FNR: 0.92%). When analyzing the cytotechnologist interpretation of the FOV, the sensitivity for detection of abnormality and HSIL was 99.89% (FNR: 0.1%), and 99.53% (FNR: 0.4%), respectively. On retrospective analysis based on newly diagnosed HSIL cases, the sensitivity of TIS was comparable to that of manual screening with a slightly decreased rate of false negatives.