In Vitro Evaluation of the Susceptibility of Edwardsiella Ictaluri, Etiological Agent of Enteric Septicemia in Channel Catfish, Ictalurus Punctatus (Rafinesque), to Florfenicol

In vitro studies were conducted to assess the sensitivity of Edwardsiella ictaluri, the etiological agent of enteric septicemia of catfish (ESC), to the antibacterial drug florfenicol (FFC). Twelve different E. ictaluri isolates from cases submitted between 1994 and 1997 to the Thad Cochran National Warmwater Aqua-culture Center fish diagnostic laboratory (Stoneville, MS) were used for testing. These isolates originated from channel catfish ( Ictalurus punctatus) infected with E. ictaluri through natural outbreaks of ESC in the commercial catfish ponds in Mississippi. Seven hundred sixty-seven additional cultures of E. ictaluri were obtained from channel catfish infected experimentally with E. ictaluri. In some of these experimental infections, FFC was used for treatment. These cultures of E. ictaluri were identified by morphological and biochemical tests. Kirby-Bauer zones of inhibition (in mm) for FFC against E. ictaluri were determined using standard methods. The minimum inhibitory concentration (MIC) of FFC was determined for the natural outbreak E. ictaluri isolates and arbitrarily selected experimental cultures. The zones of inhibition for FFC tested with E. ictaluri ranged from 31 to 51 mm. The MIC for FFC tested with E. ictaluri was consistently 0.25 μg/ml. Edwardsiella ictaluri tested in these studies were highly sensitive to FFC in vitro.

Development of a total colonoscopy rat model with endoscopic submucosal injection of the cecal wall

BACKGROUND

Experimental models of colorectal tumor require either laparotomy for induction or anastomosis following resection. The long murine cecum avoids the need for an anastomosis, making the cecum the preferred site for induction. This study aimed to evaluate total colonoscopy with submucosal injection of cecal wall (TCWI) in rats in terms of failure rate (FR), complication rate (CR), and reproducibility (R).

METHODS

A bolus of bowel prep was given. Anesthesia was injected intraperitoneally. A video fiberscope (5.9 mm outer diameter, 180/90 degrees up/down bending, 100/100 degrees right/left bending, 103 cm working length, 120 degrees view field, and 2.0 mm channel) allowed for irrigation and suction. Saline 1 ml was injected in the cecal wall through a 4-mm-long, 23-gauge needle placed on a 3-mm wire, resulting in a blister. FR was a failure to reach and inject the cecum. Rats were allowed to recover. CR was measured at necropsy. R was assessed by comparing TCWI time, FR, and CR for three investigators. Sample size of 120 (type I error, 0.05; power, 80%) was based on a pilot study. Data are presented as median (range).

RESULTS

A total of two of 122 rats (1.6%) died after prep or anesthesia. Bowel prep resulted in 99.1% evacuation of solid feces. A total of 120 male Sprague-Dawley retired breeders weighing 592 g (range, 349-780) underwent TCWI. Scope depth was 28 cm (range, 20-36). Irrigating fluid was 290 ml (range, 100-600). TCWI time was 7 min (range, 4-28). FR was 4%. In three failed cases, the scope reached the ascending colon. CR was 2%. There were two perforations in the ascending colon. All three operators had similar TCWI time (p = 0.673), FR (p > 0.1), and CR (p > 0.1). A total of 98.3% of rats survived to planned sacrifice. At 48-h necropsy, the injection site was macroscopically identified in 118 rats.

CONCLUSIONS

A safe and reproducible TCWI rat model has been achieved, which may provide a valuable tool in the future for studies of solid colorectal tumors.

The presence of colorectal hepatic metastases does not preclude pulmonary metastasectomy

Hepatic metastases due to colorectal carcinoma have often been felt to preclude pulmonary metastasectomy. With the recent advances in surgical options, should patients with both liver and lung metastases be considered for surgical resection? The current study reviews the impact of such aggressive management on disease-free and overall survival (OS). The clinical course of 63 patients presenting with colorectal metastasis to the lung alone (group 1, n = 45) or combined hepatic and lung metastases (group 2, n = 18) were reviewed. All patients underwent complete resection of their lung metastases. Surgical control of hepatic tumor burden was achieved by tumor ablation, intra-arterial therapy, and/or resection. All patients in group 1 and group 2 were available for a mean follow-up of 27 and 24 months, respectively. The presence of hepatic metastases, the resectability of hepatic tumor burden, and the disease-free interval after pulmonary metastasectomy did not significantly influence survival. These findings demonstrate that aggressive surgical management of pulmonary metastases in the presence of liver metastases offers a similar benefit as compared to patients with pulmonary metastases alone. Therefore, hepatic metastatic disease does not preclude an attempt at pulmonary metastasectomy if hepatic metastases can be resected or remains responsive to therapy. Such an approach achieves comparable OS and mean survival when compared to pulmonary metastasectomy alone.

The Presence of Colorectal Hepatic Metastases Does Not Preclude Pulmonary Metastasectomy

Hepatic metastases due to colorectal carcinoma have often been felt to preclude pulmonary metastasectomy. With the recent advances in surgical options, should patients with both liver and lung metastases be considered for surgical resection? The current study reviews the impact of such aggressive management on disease-free and overall survival (OS). The clinical course of 63 patients presenting with colorectal metastasis to the lung alone (group 1, n = 45) or combined hepatic and lung metastases (group 2, n = 18) were reviewed. All patients underwent complete resection of their lung metastases. Surgical control of hepatic tumor burden was achieved by tumor ablation, intra-arterial therapy, and/or resection. All patients in group 1 and group 2 were available for a mean follow-up of 27 and 24 months, respectively. The presence of hepatic metastases, the resectability of hepatic tumor burden, and the disease-free interval after pulmonary metastasectomy did not significantly influence survival. These findings demonstrate that aggressive surgical management of pulmonary metastases in the presence of liver metastases offers a similar benefit as compared to patients with pulmonary metastases alone. Therefore, hepatic metastatic disease does not preclude an attempt at pulmonary metastasectomy if hepatic metastases can be resected or remains responsive to therapy. Such an approach achieves comparable OS and mean survival when compared to pulmonary metastasectomy alone.

Experience and technique of stapled mechanical cervical esophagogastric anastomosis

BACKGROUND

Anastomotic leak from cervical esophagogastric anastomoses is a serious problem after esophagectomy. We explored the efficacy of partial or total mechanical anastomoses accomplished with the endoscopic linear cutting and stapling device as an alternative to hand-sewn anastomotic techniques.

METHODS

During a 42-month period, 93 patients undergoing either transhiatal esophagectomy or a three-incisional approach to esophagectomy underwent either hand-sewn (n = 43), partial mechanical (n = 16), or totally mechanical (n = 34) cervical esophagogastric anastomoses. The occurrence of postoperative anastomotic leak and the development of postoperative anastomotic stricturing requiring dilation therapy were analyzed between these groups using chi2.

RESULTS

All patients survived esophagectomy and were available for postoperative follow-up. Anastomotic leak developed in 10 patients (23%) with hand-sewn, 1 patient (6%) with partial mechanical, and 1 patient (3%) with total mechanical anastomoses (p < 0.05). Anastomotic stricture development paralleled the occurrence of anastomotic leak rate with 25 patients (58%) with hand-sewn, 3 patients (19%) with partial mechanical, and 6 patients (18%) with total mechanical anastomoses experiencing strictures requiring dilation therapy (p < 0.05).

CONCLUSIONS

These results suggest that partial or mechanical cervical esophagogastric anastomoses created with the endoscopic stapling device may be superior to hand-sewn anastomotic techniques.

Video-assisted surgical management of achalasia of the esophagus

PURPOSE

Video-assisted surgical approaches to esophageal achalasia continue to be explored by many surgeons involved in the management of this motor disorder. We report our experience with thoracoscopic and laparoscopic esophagomyotomy to more clearly define the efficacy and safety of these approaches.

PATIENTS

Over 73 months, 58 patients with achalasia underwent thoracoscopic myotomy (n = 19) alone or laparoscopic myotomy (n = 39) with partial fundoplication (anterior = 15; posterior = 24). Mean age was 47.2 years and average length of symptoms was 60 months. Primary symptoms were as follows: dysphagia, 100%; pulmonary abnormalities, 22%; weight loss; 47%, and pain, 45%. Mean esophageal diameter was 6 cm and tortuosity was present in 16% (9/58) of patients. Prior management consisted of dilation (n = 47), botulinum toxin injection (n = 8), and prior myotomy (n = 1).

METHODS

In the operating room all patients underwent endoscopic examination and evacuation of retained esophageal contents. The esophagomyotomy was extended 4 cm superiorly and inferiorly to 1 cm beyond the lower esophageal sphincter. Thoracoscopic and laparoscopic procedures were completed in all patients without conversion to an open operation. Mean operative time was 183 minutes (+/-58.1) and hospital stay averaged 2.3 days (+/-0.8). There was no operative mortality. The 1 operative complication was a perforation that was identified during the operation and repaired thoracoscopically.

RESULTS

Symptoms improved in 97% of patients. Mean dysphagia scores (range 0-10) decreased from 9.8 +/- 1.6 before the operation to 2.0 +/- 1.5 after the operation (P <.001) at a mean follow-up of 6 months. Postoperative reflux symptoms developed in 5% (1/19) of the thoracoscopy group and 8% (4/39) of the laparoscopy group. Nine patients have persistent or recurrent dysphagia (16%). Seven patients have successfully undergone Savary dilation, and 2 required esophagectomy to manage recalcitrant dysphagia.

CONCLUSION

At this intermediate term analysis, video-assisted approaches for management of achalasia are a reasonable alternative to extended medical therapy or open operations.

Intraoperative 125I brachytherapy for high-risk stage I non-small cell lung carcinoma

PURPOSE

Preliminary assessment of feasibility, efficacy, acute and chronic side effects associated with permanent intraoperative placement of 125I vicryl mesh brachytherapy in a select group of high-risk Stage I NSCLC who have undergone video-assisted thoracoscopic resection (VATR).

METHODS AND MATERIALS

From January 8, 1997 to March 16, 1998, 23 patients with Stage I NSCLC at high risk for conventional surgery due to cardiopulmonary compromise underwent combined VATR and intraoperative placement of 125I seeds embedded in vicryl mesh. Seeds embedded in vicryl suture were attached with surgical clips to a sheet of vicryl mesh, and thoracoscopically inserted over the target area (tumor bed and staple line) with nonabsorbable suture or surgical clips. A total dose of 100-120 Gy prescribed to the periphery of the target area (defined as the staple line and tumor bed with a 1-cm margin) was delivered.

RESULTS

The mean target area covered was 48 cm2 (range 40-72) and mean total activity was 22 mCi (range 17.2-28.2). The median length of postoperative stay was 7 days. The median follow-up was 11 months (range 2-20). Postoperative CT scans of the chest revealed no dislodgement of the seeds and no local recurrence in any patient. Three patients developed distant metastasis (1 died 6 months postoperatively; the other 2 are currently alive with disease). One patient developed an ipsilateral recurrence in the right lower lobe after having had a right upper lobe resection. There were 3 postoperative deaths due to medical comorbid conditions or surgical complications (1 in the immediate postoperative period). Pulmonary function testing performed 3 months after implantation revealed no significant difference between preoperative and postoperative values: mean preoperative FVC was 2.3 L (range 1.31-3.0) and postoperative FVC was 2.2 L (range 1.1-3.9), p = 0.42; mean preoperative FEV1 was 1.2 L (range 0.71-2.2), and postoperative FEV1 was 1.5 L (range 0.8-2.9), p = 0.28.

CONCLUSION

Review of early data suggests that intraoperative 125I vicryl mesh brachytherapy in high-risk Stage I NSCLC is potentially effective and well tolerated, with no significant decline in measurable pulmonary function studies and no increase in postoperative complications. Longer follow-up is needed to determine ultimate local control and survival.

Hemitruncus presenting in an adult. A case report

Hemitruncus is a rare congenital anomaly in which one pulmonary artery branch, usually the right, arises from the ascending aorta just above the aortic sinuses, whereas the main pulmonary artery and the other pulmonary branch arise in their normal position. The authors present a case in which the patient was diagnosed as having hemitruncus as an adult, and to the best of their knowledge only 7 similar cases have been reported in the medical literature.