Clinical characteristics and analysis of prognostic factors in methicillin-resistant Staphylococcus aureus endocarditis: A retrospective multicenter study in Japan.

BACKGROUND: Infective endocarditis (IE) caused by MRSA (methicillin-resistant Staphylococcus aureus) is associated with a high mortality rate. This study aimed to elucidate the characteristics of patients with MRSA-IE in Japan and identify the factors associated with prognosis. METHODS: This retrospective study included patients with a confirmed diagnosis of IE caused by MRSA, between January 2015 and April 2019. RESULTS: A total of 65 patients from 19 centers were included, with a mean age of 67 years and 26 % were female. Fifty percent of the patients with IE were had nosocomial infections and 25 % had prosthetic valve involvement. The most common comorbidities were hemodialysis (20 %) and diabetes (20 %). Congestive heart failure was present in 86 % of patients (NYHA class I, II: 48 %; III, IV: 38 %). The 30-day and in-hospital mortality rates were 29 % and 46 %, respectively. Multi-organ failure was the primary cause of death, accounting for 43 % of all causes of death. Prognostic factors for in-hospital mortality were age, disseminated intravascular coagulation, daptomycin and/or linezolid as initial antibiotic therapy, and surgery. Surgical treatment was associated with a lower mortality rate (odds ratio [OR], 0.026; 95 % confidence interval [CI], 0.002-0.382; p = 0.008 for 30-day mortality and OR, 0.130; 95 % CI; 0.029-0.584; p = 0.008 for in-hospital mortality). CONCLUSION: Mortality due to MRSA-IE remains high. Surgical treatment is a significant prognostic predictor of MRSA-IE.

Timing of re-dosing based on population pharmacokinetic-pharmacodynamics target attainment analysis of cefmetazole in subjects undergoing lower gastrointestinal surgery.

INTRODUCTION: This study was conducted to evaluate the population pharmacokinetics of prophylactic cefmetazole sodium (CMZ) based on the serum concentrations and establish a pharmacodynamics target concentration exceeding the minimum inhibitory concentration (MIC) to design the re-dosing interval. METHODS: Serum (n = 362) samples from 107 individuals were analyzed using a nonlinear mixed-effects model. The pharmacodynamics index obtained was regarded as the probability of maintaining CMZ serum trough exceeding the minimal inhibitory concentration (MIC) of 2 mg/L. This MIC was chosen to account for methicillin-susceptible Staphylococcus aureus (MSSA), E. coli, and Klebsiella pneumoniae RESULTS: The final population pharmacokinetic model was a two-compartment model with linear elimination. Creatinine clearance and body weight were identified as significant covariates influencing the central clearance and volume of distribution in the central compartment. The probability of achieving serum concentrations exceeding the MIC90 for MSSA, E. coli, and Klebsiella pneumoniae for a 1 g dose with a 10 min intravenous infusion was above 90% except for good renal function (CLcr â‰§ 95 mL/min) at 2 h after the initial dose. For patients with good renal function (CLcr â‰§ 95 mL/min), a CMZ of 2 g re-dosing interval seemed necessary to meet the achievement probability. In patients with impaired renal function (CLcr ≤20 mL/min), the probability of achievement exceeded 90% even when the dosing interval was extended to 8 h. CONCLUSIONS: We evaluated re-dosing intervals based on the population pharmacokinetics. Re-dosing intervals should be determined based on renal function.

Association of serum and fat tissue antibiotic concentrations with surgical site infections in lower gastrointestinal surgery.

BACKGROUND: During surgery, the effectiveness of perioperative prophylactic antibiotic administration against surgical site infections is inferred from serum concentrations and not from tissues where local infections occur. This study aimed to measure the serum and tissue concentrations of cefmetazole in colorectal surgery cases to clarify whether there is an association between the incidence of surgical site infections and antibiotic concentrations. METHODS: This prospective cohort study was performed at a single tertiary care center. The data of 105 patients who underwent colorectal surgery between October 2017 and September 2019 were evaluated. The primary outcome was the incidence of surgical site infections. Univariate analysis was performed to investigate the association between surgical site infections, perioperative factors, and the serum and tissue concentrations of cefmetazole. RESULTS: The incidence of surgical site infections was 13/105 (12.4%). Cefmetazole concentrations were measured at initial incision (serum; 101 vs 93.1 mg/L, P = .75, subcutaneous fat tissue; 2.8 vs 3.7 mg/g, P = .15), intestinal resection (serum; 35.1 vs 36.7 mg/L, P = .63, mesenteric adipose tissue; 1.3 vs 1.7 mg/g, P = .55), and at skin closure (serum; 34.5 vs 44.8 mg/L, P = .18, subcutaneous fat tissue; 1.0 vs 2.2 mg/g, P = .09). In univariate analysis with P ≤ .10, cefmetazole concentration in subcutaneous fat tissue at skin closure was found to be a significant risk factor for surgical site infections. Age, additional intraoperative administration of cefmetazole, and creatinine clearance were also significant risk factors for the occurrence of surgical site infections. CONCLUSION: Low subcutaneous fat cefmetazole concentrations at skin closure during gastrointestinal operations may also be involved in the occurrence of surgical site infections.

Risk Factors for Wound Infection After Laparoscopic Surgery for Colon Cancer.

OBJECTIVE: To clarify risk factors for wound infection after laparoscopic surgery for colon cancer. SUBJECTS AND METHODS: The study group comprised 1144 patients. Univariate and multivariate analyses were performed to assess the following 14 postoperative risk factors for wound infection. RESULTS: Univariate analysis showed that the following 4 risk factors were related to wound infection: tumor location right-sided colon cancer, a preoperative serum albumin level of ≤2.5 g/dL, anastomotic technique [functional end-to-end anastomosis (FEEA)], and sutures used at the time of wound closure non-polydioxanone sutures (PDS)-Plus. Multivariate analysis indicated that 3 factors were independent risk factors for wound infection: a preoperative serum albumin level of ≤2.5 g/dL, FEEA, and the use of non-PDS-Plus sutures wound closure. CONCLUSIONS: Risk factors for wound infection after laparoscopic surgery for colon cancer were a preoperative serum albumin level of ≤2.5 g/dL, FEEA, and the use of non-PDS-Plus sutures.

Risk factors for perineal wound infection after abdominoperineal resection of advanced lower rectal cancer.

PURPOSE: Abdominoperineal resection (APR) of advanced lower rectal cancer carries a high incidence of perineal wound infection. The aim of this study was to retrospectively evaluate risk factors for perineal wound infection after APR. METHODS: The study group comprised 154 patients who underwent APR for advanced lower rectal cancer in our department from January 1990 through December 2012. The following 15 variables were studied as potential risk factors for perineal wound infection: sex, age, body-mass index, American Society of Anesthesiologists score, diabetes mellitus, preoperative albumin level, preoperative hemoglobin level, neoadjuvant chemoradiotherapy(NCRT), surgical procedure (open surgery vs. laparoscopic surgery), operation time, bleeding volume, intraoperative transfusion, tumor diameter, invasion depth, and histopathological stage. RESULTS: Among the 154 patients, 30 (19%) had perineal wound infection. Univariate analysis showed that a hemoglobin level of ≤11 g/dL (p = 0.001) and NCRT (p = 0.001) were significantly related to perineal wound infection. On multivariate analysis including the preoperative albumin level (≤3.5 g/dL) in addition to the above 2 variables, neoadjuvant chemoradiotherapy (NCRT) was the only independent risk factor for perineal wound infection. Perineal wound infection developed in 31% of patients who received NCRT, as compared with 10% of patients who did not receive NCRT. The relative risk of perineal infection in the former group was 4.092 as compared with the latter group (p = 0.0002). CONCLUSIONS: NCRT is a risk factor for perineal wound infection after APR in patients with advanced lower rectal cancer.

Risk Factors for Surgical Site Infection after Laparoscopic Surgery for Colon Cancer.

BACKGROUND: Surgical site infection (SSI) occurring as a complication after laparoscopic surgery for colon cancer causes patients pain and psychological stress, prolongs the hospital stay, and increases healthcare costs. The present study was designed to clarify the incidence of, and risk factors for, SSI after surgery for colon cancer. METHODS: The study group comprised 670 patients (370 male and 300 female; mean age, 67 y) who underwent laparoscopic surgery for colon cancer in our hospital from January 2010 through April 2015. Univariate and multivariable analyses were performed for 13 risk factors potentially related to post-operative SSI, including gender, age, body mass index, diabetes mellitus, American Society of Anesthesiologists (ASA) score, tumor location, pre-operative hemoglobin concentration, pre-operative serum albumin concentration, operation time, bleeding volume, tumor diameter, pathological stage, and type of sutures used for surgical site closure. RESULTS: Surgical site infection occurred in 27 (4%) of the 670 patients. There was no surgery-related death. Univariate analysis of risk factors for SSI showed that the incidence of SSI was substantially lower in patients in whom Triclosan-coated PDS Plus(®) sutures were used for surgical site closure (1.8%, seven of 382 patients) than in those in whom Triclosan-uncoated PDS-II(™) sutures were used (6.9%, 20 of 288 patients; p = 0.0017). The incidence of SSI was substantially greater in patients who had diabetes mellitus (9.3%, seven of 75 patients) than in those who did not (3.4%, 20 of 595 patients; p = 0.0154). On multivariable analysis, only the non-use of triclosan-coated PDS Plus sutures was substantially related to SSI, with an odds ratio of 3.322 (p = 0.021) as compared with the use of triclosan-coated PDS Plus sutures. CONCLUSIONS: To prevent SSI after laparoscopic surgery for colon cancer, triclosan-coated PDS Plus sutures should be used for abdominal closure.

Definite infective endocarditis: clinical and microbiological features of 155 episodes in one Japanese university hospital.

BACKGROUND/PURPOSE: To evaluate the epidemiology, clinical features, and microbiological features (including antibiotic susceptibility) of infective endocarditis (IE) at Kitasato University Hospital, Japan. METHODS: We retrospectively analyzed 153 patients (155 episodes) with definite IE according to the Duke criteria, who presented over a 17-year period. The minimum inhibitory concentrations of antibiotics for cultured causative microorganisms were also examined. RESULTS: Viridans group streptococci were the most common pathogens (36.8%, 57 episodes), followed by Staphylococcus aureus [21.3%, 33 episodes, including 10 episodes due to methicillin-resistant S. aureus (MRSA)]. Thirty-nine of the 40 strains of viridans streptococci were fully susceptible to penicillin. Comparison of IE due to methicillin-sensitive S. aureus (MSSA) and MRSA showed that the latter had a higher mortality rate (34.8%, 8/23 vs. 70.0%, 7/10). Compared with MSSA, IE caused by MRSA was significantly more likely to be related to nosocomial infection (10/10, p < 0.001), hemodialysis (4/10, 40.0%, p = 0.005), and surgery or intravascular catheter insertion (8/10, 80.0%, p = 0.007). There was a significantly higher mortality rate in non-operated (15/43, 34.9%) than in operated (2/21, 9.5%) (p < 0.001) elderly patients. In 92/155 episodes (59.4%), antibiotics were given before blood cultures were obtained. Culture-negative IE occurred in 20.7% (19/92) of patients on antibiotics versus 6.3% (4/63) of those not on antibiotics (p = 0.02). Of 155 episodes of IE, 34 (21.9%) were fatal and staphylococcal had significantly higher mortality than streptococcal IE [(19/40, 47.5%) vs. (7/72, 9.7%); p < 0.001]. CONCLUSION: The most frequently isolated pathogens were viridans group streptococci, which differed from other recent studies. In the present study, no penicillin-resistant strains were detected and there was a higher mortality rate for IE caused by MRSA than MSSA. IE should be considered in MRSA patients with the following risk factors: nosocomial infection, hemodialysis, and surgery or intravascular catheter insertion.

[A case of Münchausen syndrome with recurrent bacteremia and PR3-ANCA positivity].

A 29-year-old woman chiropractor with repeated episodes of bacteremia and positive for cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) and antiproteinase-3 (PR3) antibody had an 11-year history of asthma and repeated hospitalization. While hospitalized she developed a spiking nocturnal fever with chills and erythema of the lower leg. Her fever resolved spontaneously, but corticosteroid therapy and antibiotics did not effectively reduce her symptoms. Plain X-ray film and CT showed pulmonary changes, and lung biopsy granulomas without vasculitis. Immunological studies showed a positive PR3-ANCA (c-ANCA) test, and skin biopsy of the crural erythema showed foreign body granuloma. Multiple blood cultures were positive for several strains of bacteria, including Fusobacterium necrophurum, Mycobacterium fortuitum, and Clostridium species. When placed in a single room and monitored, she did not develop new fever or erythema. Because self-injury was assumed, she was diagnosed as having Münchausen syndrome. This is, to our knowledge, the first report of Münchausen syndrome with PR3-ANCA positivity. In patients with repeated infections, the possibility of self-injury, the development of PR3-ANCA positivity, and pulmonary granuloma with a disease profile similar to vasculitis syndrome should be considered in the definitive diagnosis.

[A case report: Bilharzial schistosomiasis in the urinary bladder presented with gross hematuria].

A 31-year-old Japanese man who had been in Africa for two years presented with gross hematuria. He had been swimming in Lake Malawi during this period. Urinary specimen consisted of hematuria and pyuria. Cystoscopy showed tumors resembling Bilharzial tubercles located in the trigone, left lateral and posterior wall and dome. Further urine examination demonstrated eggs of schistosome haematobium. The patient was highly suspected of having Bilharzial schistosomiasis in the urinary bladder. Transurethral resection of bladder tumors was performed for diagnosis. Pathological examination revealed granuloma with many eggs of schistosome haematobium. He was diagnosed with Bilharzial schistosomiasis and was treated with 3,600 mg of praziquantel daily for two days. There have been no signs of recurrence during the one-year follow up except for excretion of degenerated eggs of schistosome haematobium in the urine specimens.