Usefulness of Blood Cultures and Radiologic Imaging Studies in the Management of Patients with Community-Acquired Acute Pyelonephritis.

BACKGROUND: The objective of this study was to examine the usefulness of blood cultures and radiologic imaging studies for developing therapeutic strategies in community-acquired acute pyelonephritis (CA-APN) patients. MATERIALS AND METHODS: We prospectively collected the clinical data of CA-APN patients who visited 11 hospitals from March 2010 to February 2011. RESULTS: Positive urine and blood cultures were obtained in 69.3% (568/820) and 42.7% (277/648), respectively, of a total of 827 CA-APN patients. Blood culture identified the urinary pathogen in 60 of 645 (9.3%) patients for whom both urine and blood cultures were performed; the organisms isolated from urine were inconsistent with those from blood in 11 and only blood cultures were positive in 49 patients. Final clinical failure was more common in the bacteremic patients than the non-bacteremic ones (8.0% vs. 2.7%, P = 0.003), as was hospital mortality (3.6% vs. 0.3%, P = 0.003). Likewise, durations of hospitalization and fever were significantly longer. Bacteremia was independent risk factor for mortality (OR 9.290, 1.145-75.392, P = 0.037). With regard to radiologic studies, the detection rate of APN was 84.4% (445/527) by abdominal computed tomography and 40% (72/180) by abdominal ultrasonography. Eighty-one of 683 patients (11.9%) were found to have renal abscess, perinephric abscess, urolithiasis, hydronephorosis/hydroureter or emphysematous cystitis, which could potentially impact on clinical management. Patients with Pitt score ≥ 1, flank pain or azotemia were significantly more likely to have such structural abnormalities. CONCLUSION: Blood cultures are clinically useful for diagnosis of CA-APN, and bacteremia is predictive factor for hospital mortality. Early radiologic imaging studies should be considered for CA-APN patients with Pitt scores ≥1, flank pain or azotemia.

Epidemiology and clinical features of post-transplant bloodstream infection: an analysis of 222 consecutive liver transplant recipients.

BACKGROUND: Bloodstream infection (BSI) is a significant cause of morbidity and mortality in liver transplant (LT) recipients. This study aimed to investigate the epidemiology and clinical features of post-transplant BSI in LT recipients. MATERIALS AND METHODS: The microbiology, frequency, and outcome of post-transplant BSI in the first year after LT were retrospectively analyzed in 222 consecutive patients who had received liver transplants at a single center between 2005 and 2011. The risk factors for post-transplant BSI and death were evaluated. RESULTS: During a 1-year period after LT, 112 episodes of BSI occurred in 64 of the 222 patients (28.8%). A total of 135 microorganisms were isolated from 112 BSI episodes including 18 polymicrobial episodes. The median time to BSI onset ranged from 8 days for Klebsiella pneumoniae to 101 days for enterococci, and the overall median for all microorganisms was 28 days. The most frequent pathogens were Enterobacteriaceae members (32.5%), enterococci (17.8%), yeasts (14.0%), Staphylococcus aureus (10.3%), and Acinetobacter baumannii (10.3%); most of them showed resistance to major antibiotics. The major sources of BSI were biliary tract (36.2%), abdominal and/or wound (28.1%), and intravascular catheter (18.5%) infections. The independent risk factors for post-transplant BSI were biliary complications (odds ratio [OR]: 2.91, 95% confidence interval [CI]: 1.29 to 6.59, P = 0.010) and longer hospitalization in the intensive care unit (OR: 1.04, 95% CI: 1.00 to 1.08, P < 0.001) after LT. BSI was an independent risk factor for death (hazard ratio [HR]: 3.92, 95% CI: 2.22 to 6.91, P < 0.001), with a poorer survival rate observed in patients with BSI than in those without BSI (1-year survival rate: 60.0% versus 89.5%, respectively, P < 0.001) after LT. The strongest predictors for death in patients with BSI were hepatocellular carcinoma (HR: 3.82, 95% CI: 1.57 to 9.32, P = 0.003), candidemia (HR: 3.71, 95% CI: 1.58 to 8.71, P = 0.003), polymicrobial bacteremia (HR: 3.18, 95% CI: 1.39 to 7.28, P = 0.006), and post-transplant hemodialysis (HR: 2.44, 95% CI: 1.02 to 5.84, P = 0.044). CONCLUSIONS: BSI was a frequent post-transplant complication, and most of the causative pathogens were multi-drug resistant. Biliary complications and BSIs resulting from biliary infection are major problems for LT recipients. The prevention of BSI and biliary complications is critical in improving prognosis in liver transplant recipients.

Incidence and risk factors for surgical site infection after gastric surgery: a multicenter prospective cohort study.

BACKGROUND: Surgical site infection (SSI) is a potentially morbid and costly complication of surgery. While gastrointestinal surgery is relatively common in Korea, few studies have evaluated SSI in the context of gastric surgery. Thus, we performed a prospective cohort study to determine the incidence and risk factors of SSI in Korean patients undergoing gastric surgery. MATERIALS AND METHODS: A prospective cohort study of 2,091 patients who underwent gastric surgery was performed in 10 hospitals with more than 500 beds (nine tertiary hospitals and one secondary hospital). Patients were recruited from an SSI surveillance program between June 1, 2010, and August 31, 2011 and followed up for 1 month after the operation. The criteria used to define SSI and a patient's risk index category were established according to the Centers for Disease Control and Prevention and the National Nosocomial Infection Surveillance System. We collected demographic data and potential perioperative risk factors including type and duration of the operation and physical status score in patients who developed SSIs based on a previous study protocol. RESULTS: A total of 71 SSIs (3.3%) were identified, with hospital rates varying from 0.0 - 15.7%. The results of multivariate analyses indicated that prolonged operation time (P = 0.002), use of a razor for preoperative hair removal (P = 0.010), and absence of laminar flow in the operating room (P = 0.024) were independent risk factors for SSI after gastric surgery. CONCLUSIONS: Longer operation times, razor use, and absence of laminar flow in operating rooms were independently associated with significant increased SSI risk after gastric surgery.

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 clinical significance of concurrent Staphylococcus aureus bacteriuria in patients with S. aureus bacteremia.

OBJECTIVE: To investigate the clinical significance of Staphylococcus aureus bacteriuria (SABU) in patients with S. aureus bacteremia (SAB). METHODS: We reviewed clinical data for 203 patients with SAB from January 2006 to July 2007 in a tertiary care hospital. In all patients, blood and urine cultures were performed concurrently. Among these cases, we compared clinical data between patients with and without SABU. To rule out mere colonization of S. aureus through indwelling urinary catheters (IDUC), we excluded patients using IDUC and then repeated the analyses. RESULTS: Concurrent SABU was observed in 31 of 203 patients (15.3%). In patients without an IDUC, 25 of 128 (19.5%) were positive for SABU. Concurrent SABU was associated with methicillin-susceptible, community-onset SAB, urinary tract obstruction/surgery, urinary tract infection, and vertebral osteomyelitis in patients with SAB. In patients without an IDUC, methicillin-susceptible SAB, urinary tract obstruction, urinary tract infection, and vertebral osteomyelitis were associated with concurrent SABU. Finally, concurrent SABU was not associated with the severity and fatality of SAB. CONCLUSION: We found that SABU was not a result of colonization via IDUC, but instead is a frequent concomitant of SAB. In septic conditions, especially without IDUC, SABU may indicate SAB with foci of infection in the urinary tract or the vertebral column.