Spread of virulent group A Streptococcus type emm59 from Montana to Wyoming, USA.

Full-genome sequencing showed that a recently emerged and hypervirulent clone of group A Streptococcus type emm59 active in Canada and parts of the United States has now caused severe invasive infections in rural northeastern Wyoming. Phylogenetic analysis of genome data indicated that the strain was likely introduced from Montana.

Evaluation of a silver nitrate endometrial ablation fluid delivery system as a chemical treatment for menorrhagia.

STUDY OBJECTIVE: To explore the safety, feasibility, and effectiveness of silver nitrate-dextran paste delivered through the cervix as a simple and inexpensive endometrial ablation therapy for menorrhagia. DESIGN: Safety, feasibility, and effectiveness trials (Canadian Task Force classification II-3). SETTING: The trials were performed at the Whittington Hospital in London. PATIENTS: Seven women were treated for menorrhagia after prehysterectomy trials on 10 patients. Studies were first performed on rats and rabbits and human uterine specimens. INTERVENTION: We dissolved 10 g 75% silver nitrate/25% potassium nitrate and 15 g dextran 70 in 10 mL distilled water and delivered this paste through the cervix with a pressure-controlled syringe under fluroscopic monitoring. We planned silver nitrate doses of 500 mg in a 50-kg woman to remain in the uterus for 8 minutes after injection and then to be neutralized with normal saline and washed out. In uterine specimens, 8-minute treatment produced local necrosis to 4 mm. LD50 (lethal dose, 50%) studies in rats and mice ranged from 1100 to 2000 mg/kg. Prehysterectomy trials on 10 patients to evaluate safety revealed no penetration into the tubes and normal complete blood count, renal, cardiac, and liver tests with plasma silver rising to 20 to 30 µmoles/L and returning to baseline after 4 weeks. Finally, 7 patients were treated and followed for 6 months. We followed blood values, complications, and degree of flow reduction. Six patients were well and discharged the same day; of those, all blood values were similar to the safety studies, 5 reported varying degrees of flow reduction, and 1 patient continued with menorrhagia. The seventh patient had passage of paste into the left fallopian tube and peritoneal cavity producing immediate pain. Laparoscopy showed several burns on the back of the uterus, sigmoid colon, and cul de sac. After neutralization with saline, she made a complete, uneventful recovery and became oligoamenorrheic. CONCLUSION: Silver nitrate could be a simple, inexpensive, safe, and potentially effective agent for endometrial ablation. However, to ensure safety, the fluid delivery system described herein must be abandoned. An alternative delivery system is needed, one which precisely controls the locus of caustic action, and further testing is required for effectiveness and safety.

The incidence of endometrial cancer after endometrial ablation in a low-risk population.

STUDY OBJECTIVE: To assess the incidence of endometrial cancer in 509 women who had undergone hysteroscopic endometrial ablation in two centers between 1978 and 1994. All patients had normal endometrial histology before ablation. DESIGN: Retrospective cohort study (Canadian Task Force classification II-2). SETTING: Teaching hospital-affiliated private practices. PATIENTS: Five hundred nine women with perimenopausal bleeding. INTERVENTION: The patients were contacted directly, by mail or phone, and asked if they had had a diagnosis or treatment for cancer or precancer of the endometrium. The list of unreachable patients was submitted to the National Death Index. After this, names and other pertinent data of the remaining patients were submitted to the Cancer Registries of the 50 states and Washington, DC. Forty-two patients were omitted from these searches due to insufficient information or because they were unreachable, and one excluded because of a diagnosis of Bloom's syndrome. The comparative incidence was obtained from the U.S. SEER data of age-specific rates of endometrial cancer published by the National Cancer Institute. MEASUREMENTS AND MAIN RESULTS: Fifty-one percent of the patients were contacted directly yielding one case of endometrial cancer. Eight patients had died, but none from endometrial cancer. One patient was located in the New Jersey Cancer Registry. A total of 5063 woman-years was identified with two cases of endometrial cancer. The expected incidence was 1.66 cases in an age-matched group with known length of follow-up from the U.S. SEER data. There is no significant difference between the two groups. CONCLUSION: The flaws in the databases include the lack of data on subsequent hysterectomy for benign disease in both the treated group and the SEER database. Low risk for endometrial cancer is narrowly defined to normal endometrium preablation. Nevertheless, the data give an approximation of the incidence for endometrial cancer, and should serve as a benchmark for prospective studies in patients undergoing endometrial ablation as well as a resource to counsel patients in the choice between ablation and hysterectomy.