Malignant ureteral obstruction: experience and comparative analysis of metallic versus ordinary polymer ureteral stents.

BACKGROUND: To study the outcome and experience of using metallic stents in treating patients with malignant ureteral obstruction (MUO). METHODS: Seventy-six patients with MUO were assigned to the metallic stent group (MSG) or the ordinary polymer stent group (OPSG) according to the different materials. The success rate of the operation, duration of operation, patency rate serum creatinine values ,postoperative complications and QOL scores were compared between the two groups. RESULTS: In the OPSG and MSG, the success rates of the operation were 95.5% and 96.9%, respectively, and the durations of the operation were 20.6 ± 2.2 min and 50.9 ± 10.3 min (P < 0.01), respectively. There was no significant difference between the groups in serum creatinine values at 3 days after the operation (P > 0.05); however, the creatinine values at 3 days after the operation decreased significantly compared with those before the operation (P < 0.01). In the OPSG, there was no significant difference in creatinine values between 3 days and 6 months after operation, while the creatinine values 1 year after operation were increased significantly compared to those at 3 days after the operation (P < 0.05). In the MSG, there was no significant difference among creatinine values at different intervals (P > 0.05). The total rate of post-procedural complication was lower in the MSG than that in the OPSG(P < 0.05). There was no significant difference in the QOL score between the two groups before the operation (P > 0.05); however, the QOL scores at 6 months and 1 year after the operation were higher in the MSG than that in the OPSG(P < 0.05). In the MSG, there was no significant difference in the QOL score between preoperation and 6 months after surgery. Similarly, there was also no difference in the QOL score between 6 months after surgery and 1 year after surgery(P > 0.05). On the contrary, the differences of QOL score in the OPSG group were much significant between disparate time intervals (P < 0.05). CONCLUSIONS: For patients with MUO who require long-term retention of the stent, metallic stents with longer indwelling time are superior to ordinary polymeric stents.

[Study on the natural foci of Marmota himalayana plague in Sichuan province].

OBJECTIVE: To explore the existence of natural foci on Marmota himalayana plague in Sichuan province and to provide basis for prevention and control of the disease. METHODS: Both epidemiological investigation and laboratory tests were used to provide the host animal and fleas of the vectors with Yersinia pestis carriers. RESULTS: 30 species of animals were found to belong to 10 orders. Ochotona curzoniae and M. himalayana were the most common ones while 7 species of the fleas belonged to 7 genera and 3 families. M. himalayana was the main reservoirs while Callopsylla dolabris and Oropsylla silantiewi served as vectors. The 13 Y. pestis were identified from 43 Marmota samples. 8 samples were identified under IHA, with the highest titer of herding-dogs serum as 1:10,240. 19 samples were F1 antigen positive using RIHA and the highest titer of M. himalayana serum was 1:409,600. The major foci was 4545 km2, distributed at Dege county in Sichuan province. CONCLUSION: We have confirmed the existence of natural foci on M. himalayana plague in Sichuan province.