Wide dissemination of OXA-type carbapenemases in clinical Acinetobacter spp. isolates from South Korea

Carbapenem-resistant Acinetobacter spp. are being increasingly reported worldwide, including in South Korea, where we examined 144 representative isolates collected in a nationwide hospital survey in 2005. Metallo-β-lactamases were detected in only 19.4% of isolates, none of which were Acinetobacter baumannii, whereas 74.3% of isolates (mostly A. baumannii) expressed bla_OXA carbapenemase genes. Among the latter, 47 had bla_OXA-23-like genes and 56 had upregulated bla_OXA-51-like variants, including bla_OXA-66, _-83, _-109 and _-115; bla_OXA-115 was a novel variant, detected in two isolates. bla_OXA-72 (bla_OXA-40-like) was detected in only a single Acinetobacter baylyi isolate, whilst three Acinetobacter calcoaceticus isolates had both bla_VIM-2-like and bla_OXA-58 genes. Pulsed-field gel electrophoresis (PFGE) suggested the spread of A. baumannii clones with OXA carbapenemases within and between hospitals. In conclusion, the recent increase in imipenem-resistant Acinetobacter spp. from South Korea is mostly due to OXA-type carbapenemases.     

Intestinal parasitic infection

In general, gastrointestinal tract is the primary involvement site of parasites during their life cycle. In this article, we will describe amebiasis, ascariasis, and anisakiasis among the many common intestinal parasitic diseases. We will review the epidemiology, life cycles, clinical manifestations and complications, and illustrate detailed imaging findings of intestinal parasites. Recognizing features of parasitic infection is important to establish an early diagnosis that leads to prompt treatment and helps avoid unnecessary surgery.     

Preoperative Radiologic and Postoperative Pathologic Risk Factors for Early Intra-Hepatic Recurrence in Hepatocellular Carcinoma Patients Who Underwent Curative Resection

Purpose

The risk of hepatocellular carcinoma (HCC) recurrence must be considered ahead of surgery. This study was undertaken to identify pre-operative risk factors for early intrahepatic recurrence of HCC after curative resection in a large-scale.

Materials and Methods

We retrospectively reviewed the preoperative three-phase multi-detector CT (MDCT) and laboratory data for 240 HCC patients who underwent curative resection; tumor size, number, gross shape, capsule integrity, distinctiveness of tumor margin, portal vein thrombosis (PVT), alpha-fetoprotein level (AFP), and protein induced by vitamin K absence-II (PIVKA-II) levels were assessed. Surgical pathology was reviewed; tumor differentiation, capsule, necrosis, and micro-vessel invasion were recorded.

Results

HCC recurred in 61 patients within six months (early recurrence group), but not in 179 patients (control group). In univariate analysis, large tumor size (p = 0.018), shape (p = 0.028), poor capsule integrity (p = 0.046), elevated AFP (p = 0.015), and PIVKA-II (p = 0.008) were significant preoperative risk factors. Among the pathologic features, PVT (p = 0.023), Glisson''s capsule penetration (p = 0.033), microvascular invasion (p < 0.001), and poor differentiation (p = 0.001) showed statistical significance. In multivariate analysis, only the histopathologic parameters of microvascular invasion and poor differentiation achieved statistical significance.

Conclusion

Preoperative CT and laboratory parameters showed limited value, while the presence of microscopic vascular tumor invasion and poorly differentiated HCC correlated with higher risk of early recurrence after curative resection.     

The Inhibitory Effect of Quercetin-3-O-��-D-Glucuronopyranoside on Gastritis and Reflux Esophagitis in Rats

It was evaluated the inhibitory action of quercetin-3-O-β-D-glucuronopyranoside (QGC) on reflux esophagitis and gastritis in rats. QGC was isolated from the herba of Rumex Aquaticus. Reflux esophagitis or gastritis was induced surgically or by administering indomethacin, respectively. Oral QGC decreased ulcer index, injury area, gastric volume, and acid output and increased gastric pH as compared with quercetin. Furthermore, QGC significantly decreased gastric lesion sizes induced by exposing the gastric mucosa to indomethacin. Malondialdehyde levels were found to increase significantly after inducing reflux esophagitis, and were reduced by QGC, but not by quercetin or omeprazole. These results show that QGC can inhibit reflux esophagitis and gastritis in rats.     

Efficient differentiation of Mycobacterium abscessus complex isolates to the species level by a novel PCR-based variable-number tandem-repeat assay

A novel duplex PCR method based on variable-number tandem-repeat targets to discriminate among Mycobacterium abscessus complex isolates was developed and evaluated in 85 clinical isolates. The assay accuracy was confirmed by a multiple-target sequence analysis. The duplex PCR assay is a one-step, reliable, and accurate assay for discriminating M. abscessus species.     

Differentiation of Adrenal Adenoma and Nonadenoma in Unenhanced CT: New Optimal Threshold Value and the Usefulness of Size Criteria for Differentiation

Objective

To determine the optimal threshold for the attenuation values in unenhanced computed tomography (CT) and assess the value of the size criteria for differentiating between an adrenal adenoma and a nonadenoma.

Materials and Methods

The unenhanced CT images of 45 patients at our institution, who underwent a surgical resection of an adrenal masses between January 2001 and July 2005, were retrospectively reviewed. Forty-five adrenal masses included 25 cortical adenomas, 12 pheochromocytomas, three lymphomas, and five metastases confirmed by pathology were examined. The CT images were obtained at a slice thickness of 2 mm to 3 mm. The mAs were varied from 100 to 160 and 200 to 280, while the 120 KVp was maintained in all cases. The mean attenuation values of an adrenal adenoma and nonadenoma were compared using an unpaired t test. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy at thresholds of 10 HU, 20 HU, and 25 HU were compared. The diagnostic accuracy according to the size criteria from 2 cm to 6 cm was also compared.

Results

The twenty-five adenomas showed significantly lower (p < 0.05) attenuation values(mean ± SD; 16.3 ± 14.9) than the nonadenomas (38.1 ± 6.8). Nineteen (90%) of the 20 nonadenomas had attenuation values ranging from 30 to 50 HU. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing adenomas were 36%, 100%, 100%, 56%, and 64%, respectively, at a threshold of 10 HU; 60%, 100%, 100%, 67%, and 78%, respectively, at a threshold of 20 HU; and 72%, 95%, 95%, 73%, and 82%, respectively, at a threshold of 25 HU. The adenomas had a significantly (p < 0.05) smaller diameter (2.44 ± 1.24 cm) than the nonadenomas (5.09 ± 2.37 cm). The size criteria using a diameter of 4-6 cm showed a sensitivity > 90% but a specificity < 70%. Size criteria of 2 or 3 cm had a high specificity of 100% and 80% but a low sensitivity of 20% and 60%.

Conclusion

The threshold attenuation values of 20 or 25 HU in the unenhanced CT appear optimal for discriminating an adrenal adenoma from a nonadenoma. The size criteria are of little value in differentiating adrenal masses because of their low specificity or low sensitivity.