Distinguishing coagulase-negative Staphylococcus bacteremia from contamination using blood-culture positive bottle detection pattern and time to positivity.

AIM: Detection of coagulase-negative Staphylococcus in blood culture may be a result of either bacteremia or contamination. This often leads to diagnostic uncertainly. Our objective was to develop a method for differentiating whether a coagulase-negative Staphylococcus sp. positive blood culture represents bacteremia or contamination based on positive bottle detection pattern and time to positivity (TTP). METHODS: This study included 155 and 51 adults with positive blood cultures for Staphylococcus epidermidis and Staphylococcus hominis, respectively, over a three-year period from 2016 to 2018. Positive blood culture cases were categorized as either bacteremia or contamination based on the clinically available information, and the detection pattern and TTP in each category were investigated. RESULTS: A total of 57, 92, and 6 S. epidermidis positive blood cultures were categorized as bacteremia, contamination, and undetermined, respectively, whereas 15 and 36 S. hominis positive blood cultures were categorized as bacteremia and contamination, respectively. For positive blood cultures categorized as bacteremia, all four bottles in two sets of blood cultures were positive in 47/47 S. epidermidis and 14/14 S. hominis, respectively, whereas either one bottle in each of two sets or three bottles in two sets were positive in 10/19 S. epidermidis and 1/4 S. hominis, respectively; most of those TTPs were <48 h. Among them, the TTP in catheter-related blood stream infection was <24 h. CONCLUSION: Although clinical assessment is crucial to differentiate between bacteremia and contamination, a combination of positive bottle detection pattern and TTP is a valuable diagnostic auxiliary tool.

Novel anti-reflux biliary metal stent with a distal tapered end for distal malignant biliary obstruction: a feasibility study.

Background and study aims We developed a self-expandable metallic stent (SEMS) with a distal tapered end to reproduce the physiological bile flow with a pressure gradient due to the difference in the diameter. We aimed to evaluate the safety and efficacy of the newly developed distal tapered covered metal stent (TMS) for distal malignant biliary obstruction (DMBO). Patients and methods This single-center, prospective, single-arm study was conducted in patients with DMBO. The primary endpoint was time to recurrent biliary obstruction (TRBO), and the secondary endpoints were the survival time and incidence of adverse events (AEs). Results Thirty-five patients (15 men, 20 women; median age, 81 years [range: 53-92]) were enrolled between December 2017 and December 2019. The primary diseases were pancreatic head cancer in 25 cases, bile duct cancer in eight cases, and ampullary cancer in two cases. TMS was successfully placed in all cases. Acute cholecystitis occurred as an early AE (within 30 days) in two cases (5.7 %). The median TRBO was 503 days, median survival time was 239 days. RBO was observed in 10 cases (28.6 %), and the causes were distal migration in six cases, proximal migration in two cases, biliary sludge in one case, and tumor overgrowth in one case. Conclusions Endoscopic placement of the newly developed TMS in patients with DMBO is technically feasible and safe, and the TRBO was remarkably long. The anti-reflux mechanism based on the difference in diameter may be effective, and a randomized controlled trial with a conventional SEMS is required.

Disseminated Bone Marrow Carcinomatosis Due to Malignant Melanoma of Unknown Primary Origin.

An 80-year-old woman was admitted to our hospital due to appetite loss and vomiting. A blood examination showed liver disorder with disseminated intravascular coagulation. All tumor markers and hepatitis virus markers were negative. Contrast-enhanced computed tomography did not show tumor lesions, bone lesions, lymphadenopathies, or thrombosis. A bone marrow biopsy revealed large, atypical cells with brown pigmentation and positive immunostaining for HMB-45, S100 proteins, and CD79a without myeloid or lymphoid markers. We experienced a case of disseminated carcinomatosis of the bone marrow due to malignant melanoma of unknown primary origin.

Chemotherapy with gemcitabine for unresectable intrahepatic cholangiocarcinoma in a patient undergoing maintenance hemodialysis.

A 56-year-old man with chronic renal failure due to diabetic nephropathy had received maintenance dialysis (every 4 h, three times/week). A hypoechoic tumor measuring 67 × 50 mm in the right lobe of the liver was discovered following routine abdominal ultrasonography. Dynamic computed tomography showed a low-density liver tumor, enlarged hilar lymph node, and a small nodule on the dorsal side of the lower lobe of the left lung. Histopathological examination of the liver tumor revealed intrahepatic cholangiocarcinoma. We developed a chemotherapy treatment plan with gemcitabine, which can be performed concurrently with hemodialysis. Gemcitabine (1000 mg/m2, three times/cycle) was administered on Friday afternoon, and hemodialysis was performed on Tuesday, Thursday, and Saturday. Anemia and hypotension occurred after gemcitabine administration. Therefore, the dose of darbepoetin alpha was increased, and packed red blood cells were transfused. The patient was treated with gemcitabine for approximately 5 and a half months until computed tomography findings showed progressive disease; the survival time after treatment start was 8 months. Chemotherapy using gemcitabine has not been established in dialysis patients and has little evidence. We report a case of unresectable intrahepatic cholangiocarcinoma that developed during maintenance dialysis and was treated using gemcitabine chemotherapy.