Performance of Gram staining on blood cultures flagged negative by an automated blood culture system.

Blood is one of the most important specimens sent to a microbiology laboratory for culture. Most blood cultures are incubated for 5-7 days, except in cases where there is a suspicion of infection caused by microorganisms that proliferate slowly, or infections expressed by a small number of bacteria in the bloodstream. Therefore, at the end of incubation, misidentification of positive cultures and false-negative results are a real possibility. The aim of this work was to perform a confirmation by Gram staining of the lack of any microorganisms in blood cultures that were identified as negative by the BACTEC™ FX system at the end of incubation. All bottles defined as negative by the BACTEC FX system were Gram-stained using an automatic device and inoculated on solid growth media. In our work, 15 cultures that were defined as negative by the BACTEC FX system at the end of the incubation were found to contain microorganisms when Gram-stained. The main characteristic of most bacteria and fungi growing in the culture bottles that were defined as negative was slow growth. This finding raises a problematic issue concerning the need to perform Gram staining of all blood cultures, which could overload the routine laboratory work, especially laboratories serving large medical centers and receiving a large number of blood cultures.

BACTEC FX system as a tool for culturing gastric biopsies and Helicobacter pylori diagnosis.

Helicobacter pylori infection represents a key factor in the etiology of various gastrointestinal diseases. There are several acceptable methods to identify this microorganism. Some are invasive and some are noninvasive. This study demonstrates the use of BACTEC FX system for the growth and diagnosis of H. pylori isolated from gastric biopsy specimens, cut and placed in blood culture bottles, with subsequent incubation in the apparatus. Twenty-five positive and 15 negative biopsy samples tested using the quick urease technique, CUTest, were collected from 40 patients with confirmed chronic gastric inflammation. The biopsy samples were manually cut using a sterile scalpel and placed in tubes containing 5 ml of fetal bovine serum. The resulting suspensions were transferred using a syringe into anaerobic blood culture bottles. These bottles were incubated at 35 °C for a period of 7 days in the BACTEC FX system. All biopsy samples that reacted positive to the CUTest and one biopsy sample that reacted negative to the CUTest were confirmed as positive by the BACTEC FX system. In addition, there was a correlation between the positive culture and histology examination results. The use of BACTEC FX system significantly shortens the time needed for culturing, which makes the system more efficient in the identification of H. pylori. It should be emphasized that performing microbial culture testing has a significant role in monitoring antibiotic resistance, which cannot be done using other existing methods for H. pylori diagnosis.

Peroral transgastric endoscopic primary repair of a ventral hernia in a porcine model.

BACKGROUND AND STUDY AIMS: Multiple studies have demonstrated the feasibility of peroral transgastric endoscopic procedures in animal models. The aim of the study was to evaluate the feasibility of a peroral transgastric endoscopic approach to repair abdominal wall hernias. PATIENTS AND METHODS: We performed acute experiments under general anesthesia with endotracheal intubation using 50-kg pigs. Following peroral intubation an incision of the gastric wall was made and the endoscope was advanced into the peritoneal cavity. An internal anterior abdominal wall incision was performed with a needle knife to create an animal model of a ventral hernia. After hernia creation an endoscopic suturing device was used for primary repair of the hernia. After completion of the hernia repair the endoscope was withdrawn into the stomach and the gastric wall incision was closed with endoscopic clips. Then the animals were killed for necropsy. RESULTS: Two acute experiments were performed. Incision of the gastric wall was easily achieved with a needle knife and a pull-type sphincterotome. A large (3 x 2 cm) defect of the abdominal wall (ventral hernia model) was closed with five or six sutures using the endoscopic suturing device. Postmortem examination revealed complete closure of the hernia without any complications. CONCLUSIONS: Transgastric endoscopic primary repair of ventral hernias in a porcine model is feasible and may be technically simpler than laparoscopic surgery.

Hybrid minimally invasive surgery--a bridge between laparoscopic and translumenal surgery.

BACKGROUND: The peroral transluminal approach to the peritoneal cavity appears safe, feasible, and may further reduce the invasiveness of surgery. However, flexible endoscopes have multiple limitations inside the peritoneal cavity, which can potentially be overcome by blending the use of both a laparoscope and a flexible upper endoscope--a hybrid approach. The goal of the present study was to evaluate a hybrid minimally invasive technique for cholecystectomy in a porcine model. METHODS: Hybrid cholecystectomies were performed in acute experiments on 50-kg pigs under general anesthesia. Pneumoperitoneum was created with a Veress needle, and a laparoscopic 10-mm port was inserted. Under laparoscopic observation, the gastric wall incision was done with an endoscopic needle-knife and sphincterotome, and the upper endoscope was advanced into the peritoneal cavity. A laparoscopic 10-mm port was inserted into the right upper quadrant of the abdomen for gallbladder traction to facilitate exposure of the cystic duct and artery. Via the biopsy channel of the flexible endoscope, and using a knife with an isolated tip, a needle knife, and clips, both the cystic duct and artery were identified, clipped, and transected. The gallbladder itself was then dissected and retracted through the mouth, and the gastric wall incision was closed with endoscopic clips. RESULTS: Five hybrid cholecystectomies were performed without complications. The laparoscopic port enabled a stable pneumoperitoneum, good traction and counter-traction, and improved spatial orientation and visualization. Necropsy did not reveal any intraperitoneal complications. CONCLUSIONS: The hybrid approach increases safety of initial gastric puncture and gastric wall incision, improves orientation and navigation of the flexible endoscope inside the peritoneal cavity, simplifies peroral transgastric cholecystectomy, and could be used to decrease invasiveness of laparoscopic surgery and to facilitate development and clinical introduction of transgastric endoscopic procedures. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00464-007-9329-2) contains supplementary material, which is available to authorized users.