Risk factors for surgical site infection after gastric surgery: a multicentre case-control study.

BACKGROUND: Surgical site infection (SSI) is a potentially morbid and costly complication of surgery. We conducted a multicentre case-control study to determine the risk factors for SSI in patients undergoing gastric surgery and to establish strategies to reduce the risk of SSI. METHODS: Between January 2007 and December 2008, 121 patients who developed an SSI after gastric surgery were matched with controls who had undergone surgery on the dates closest to those of the cases, at 13 centres in Korea. RESULTS: The results of multivariate analyses showed that the independent risk factors for SSI after gastric surgery were older age (p = 0.016), higher body mass index (BMI) (p = 0.033), male gender (p = 0.047), and longer duration of prophylactic antibiotic use (p < 0.001). CONCLUSION: Older age, higher BMI, male gender, and longer duration of prophylactic antibiotic use were independently associated with significant increases in the risk of SSI. Additional prospective randomized studies are required to confirm these results.

The characteristics of metallo-ß-lactamase-producing gram-negative bacilli isolated from sputum and urine: a single center experience in Korea.

Metallo-ß-lactamase (MBL) production usually results in high-level resistance to most ß-lactams, and a rapid spread of MBL producing major gram-negative pathogens is a matter of particular concern worldwide. However, clinical data are scarce and most studies compared MBL producer (MP) with MBL non-producer (MNP) strains which included carbapenem susceptible isolates. Therefore, we collected clinical data of patients in whom imipenem-nonsusceptible Pseudomonas aeruginosa (PA) and Acinetobacter baumannii (AB) were isolated from sputum or urine, and investigated MBL production and the risk factors related with MBL acquisition. The antimicrobial susceptibility patterns were also compared between MPs and imipenem-nonsusceptible MNPs (INMNP). Among the 176 imipenem-nonsusceptible isolates, 12 MPs (6.8%) were identified. There was no identifiable risk factor that contributed to the acquisition of MPs when compared to INMNPs, and case-fatalities were not different between the two groups. The percentage of susceptible isolates was higher among MPs for piperacilin/tazobactam and fluoroquinolones while that of ceftazidime was higher in INMNPs (p < 0.05). As regards to aztreonam, which has been known to be a uniquely stable ß-lactam against MBLs, susceptibility was preserved in only two isolates (16.7%) among MPs, and was not higher than that of INMNPs (23.2%). In conclusion, the contribution of MBLs to imipenem non-susceptibility in PA/ABs isolated from sputum and urine was relatively limited, and there was no significant risk factor associated with acquisition of MPs compared with INMNPs. However, limited susceptibility to aztreonam implies that MPs may hold additional resistance mechanisms, such as extended spectrum ß-lactamases, AmpC ß-lactamases, or other non-enzymatic mechanisms.

Disseminated Mycobacterium kansasii infection associated with skin lesions: a case report and comprehensive review of the literature.

Mycobacteruim kansasii occasionally causes disseminated infection with poor outcome in immunocompromised patients. We report the first case of disseminated M. kansasii infection associated with multiple skin lesions in a 48-yr-old male with myelodysplastic syndrome. The patient continuously had taken glucocorticoid during 21 months and had multiple skin lesions developed before 9 months without complete resolution until admission. Skin and mediastinoscopic paratracheal lymph node (LN) biopsies showed necrotizing granuloma with many acid-fast bacilli. M. kansasii was cultured from skin, sputum, and paratracheal LNs. The patient had been treated successfully with isoniazid, rifampin, ethmabutol, and clarithromycin, but died due to small bowel obstruction. Our case emphasizes that chronic skin lesions can lead to severe, disseminated M. kansasii infection in an immunocompromised patient. All available cases of disseminated M. kansasii infection in non HIV-infected patients reported since 1953 are comprehensively reviewed.

Blood stream infections by Candida glabrata and Candida krusei: a single-center experience.

BACKGROUND/AIMS: The increasing incidence of Candida glabrata and Candida krusei infections is a significant problem because they are generally more resistant to fluconazole. We compared the risk factors associated with C. glabrata and C. krusei fungemia with Candida albicans fungemia and examined the clinical manifestations and prognostic factors associated with candidemia. METHODS: We retrospectively reviewed demographic data, risk factors, clinical manifestations, and outcomes associated with C. glabrata and C. krusei fungemia at a tertiary-care teaching hospital during a 10-years period from 1997 to 2006. RESULTS: During the study period, there were 497 fungemia episodes. C. glabrata fungemia accounted for 23 episodes and C. krusei fungemia accounted for 8. Complete medical records were available for 27 of these episodes and form the basis of this study. Compared to 54 episodes of C. albicans fungemia, renal insufficiency and prior fluconazole prophylaxis were associated with development of C. glabrata or C. krusei fungemia. The overall mortality was 67%. The fungemia-related mortality of C. glabrata and C. krusei was higher than that of C. albicans (52 vs. 26%, p=0.021). Empirical antifungal therapy did not decrease the crude mortality. Multiple logistic regression analysis showed that high APACHE II scores, catheter maintenance, and shock were independently associated with an increased risk of death. CONCLUSIONS: Renal insufficiency and prior fluconazole prophylaxis were associated with the development of C. glabrata or C. krusei fungemia. Fungemia-related mortality of C. glabrata or C. krusei was higher than that of C. albicans. Outcomes appeared to be related to catheter removal, APACHE II scores, and shock.

Diagnosis and species identification of mycobacterial infections by polymerase chain reaction-restriction fragment length polymorphism analysis of sterile body fluids.

BACKGROUND/AIMS: The development of effective, accurate, and rapid diagnostic methods for Mycobacterium infection and mycobacterial species identification is required. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) is an easy, rapid and inexpensive technique for identifying Mycobacterium spp. METHODS: We performed PCR-RFLP to detect and identify Mycobacterium spp. from 10 sterile body fluids, including ascites, cerebrospinal fluid, pleural fluid, synovial fluid, and peritoneal dialysis fluid. Clinical samples were collected from patients with diagnoses of definite, probable or suspected mycobacterial infection. The conserved RNA polymerase genes of Mycobacterium spp. were amplified by PCR. RESULTS: The amplified 360-bp region of rpoB was digested with the restriction enzyme MspI or HaeIII. The PCR-RFLP results for the clinical samples were identical to those for M. tuberculosis, M. fortuitum, M. intracellulare, and M. avium. In addition, the results of the PCR-RFLP were identical to those obtained by DNA sequencing. CONCLUSIONS: PCR-RFLP analysis of sterile body fluids may be a useful method for the diagnosis of mycobacterial infections and for the differentiation of mycobacterial species.

Factors associated with HIV-1 proviral DNA loads in patients with undetectable plasma RNA load.

To evaluate factors associated with human immunodeficiency virus type 1 (HIV-1) proviral DNA load, we conducted a cross-sectional study of 36 chronically HIV-1-infected individuals with undetectable plasma viral RNA. We used real-time polymerase chain reaction to determine the number of HIV-1 proviral DNA copies per 10(6) peripheral blood mononuclear cells. The mean level of plasma viral RNA when the CD4+ T cell count was above 500 cells/microL without highly active antiretroviral therapy (HAART) was significantly associated with proviral DNA load at the time of undetectable plasma HIV RNA with HAART. Strategies to reduce the level of plasma viral RNA when patients' CD4+ T cell counts are above 500 cells/microL without HAART could help reduce HIV-1 proviral DNA load.

Two cases of multidrug-resistant human immunodeficiency virus infection treated with atazanavir and lopinavir/ritonavir combination therapy.

The combination of atazanavir (ATV) and lopinavir/ritonavir (LPV/RTV) with nucleoside reverse transcriptase inhibitors (NRTI) has been used as a salvage regimen for human immunodeficiency virus (HIV)-positive patients. In this paper, we discuss two cases of HIV-positive patients who had long histories of virological failure following a heavy treatment of antiretroviral drugs, but then achieved virological suppression with double-boosted protease inhibitor (PI) regimens. In patients with multiple genotypic resistance to PIs and NRTIs, virological suppression can be achieved with a combination of ATV plus LPV/RTV with an NRTI backbone. The two cases in this report suggest that a combination of ATV plus LPV/RTV could be a useful salvage regimen for the subset of HIV-positive patients with limited treatment options.

LPS-induced vascular endothelial growth factor expression in rat lung pericytes.

Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor. Recent studies have shown that the VEGF levels increase in several cell types, for example, macrophages and smooth muscle cells after LPS stimulation, suggesting that it is important in the initiation and development of sepsis. In particular, LPS-regulated contractility in lung pericytes may play an important role in mediating pulmonary microvascular fluid hemodynamics during sepsis. This study investigated the production of VEGF by rat lung pericytes in response to LPS. LPS was found to enhance VEGF mRNA expression in a concentration-dependent manner peaking 2 h after stimulation in pericytes. Vascular endothelial growth factor protein levels in conditioned medium and in cell lysate also increased on increasing LPS and peaked after 24 to 48 h. LPS also significantly augmented iNOS expression in lung pericytes within 6 h. However, iNOS mRNA induction occurred later than LPS-induced VEGF mRNA increases. Interestingly, attempted inhibition with nuclear factor-kappaB or tyrosine kinase did not suppress LPS-induced augmented VEGF mRNA expression in lung pericytes, although both inhibitors markedly inhibited LPS-induced iNOS mRNA expression. SB203580, a p38 MAP kinase inhibitor, repressed LPS-induced VEGF mRNA expression. Furthermore, LPS stimulated a rapid and sustained phosphorylation of p38 MAP kinase. These results show that pericytes produce VEGF in response to LPS stimulation, and that this may be partly mediated by the p38 MAP kinase pathway. More research should be done to establish the regulation of capillary hemodynamics and identify mechanisms of their regulation.

Risk factors and outcomes of bloodstream infections with metallo-beta-lactamase-producing Acinetobacter.

The spread of Gram-negative bacilli with acquired metallo-beta-lactamase (MBL) threatens the successful treatment of major nosocomial infections. The objective of this study was to evaluate the differences in the clinical characteristics of bacteremia caused by MBL-producing Acinetobacter species and MBL non-producing isolates. Two retrospective case-control studies were conducted using data on patients with Acinetobacter bacteremia, who were admitted between January 2001 and December 2005 at a 1500-bed, tertiary-care teaching hospital. Case group 1 (n=27) included patients from whom imipenem-resistant Acinetobacter was isolated in blood culture, and case group 2 (n=7) consisted of those patients from group 1 who yielded MBL-producing isolates. The control group (n=41) included patients from whom carbapenem-susceptible Acinetobacter isolates were isolated in blood culture. Multivariate analysis revealed that the independent risk factors for imipenem-resistant Acinetobacter bacteremia were neutropenia and prolonged use of carbapenem. The independent risk factors for MBL-producing Acinetobacter bacteremia were neutropenia and prolonged use of cephalosporins. The results of this study suggest that a prolonged use of cephalosporins may be associated with MBL-producing Acinetobacter bacteremia.

A case of lactic acidosis caused by stavudine in an AIDS patient.

Nucleoside reverse transcriptase inhibitors (NRTIs), which are used for the treatment of human immunodeficiency virus (HIV) infection have been associated with a wide spectrum of clinical manifestations, including hepatic steatosis, lipodystrophy, myopathy, and lactic acidosis. Such adverse effects are postulated to result from the inhibition of mitochondrial DNA gamma polymerase, which causes the depletion of mitochondrial DNA and eventual the disruption of oxidative phosphorylation. Although cases of severe decompensated lactic acidosis are rare, this syndrome is associated with a high mortality rate. We report upon the first Korean case, of severe lactic acidosis in an acquired immunodeficiency syndrome (AIDS) patient receiving stavudine, an anti-HIV drug.

[A case of Crohn's disease with iliac arterio-enteric fistulae].

Arterioenteric fistula is rare but can cause life-threatening bleeding. A case of Crohn's disease with severe gastrointestinal hemorrhage caused by iliac arterioenteric fistula is presented. A 36-year-old male with Crohn's disease was admitted because of massive lower gastrointestinal bleeding, which required transfusion of 16 units of packed RBCs over 2 days. Radioisotope RBC scan revealed intestinal bleeding directly from the right iliac artery. Emergent operation confirmed iliac arterioenteric fistulae with active bleeding, There was no further intestinal bleeding after surgery. Remission had been maintained for 3 years with mesalazine.