Evaluation of Real-time PCR and Gomori-Methenamine Silver Stain for Diagnosing of Pneumocystis Pneumonia / 现代检验医学杂志

Objective To compare real-time PCR and gomori-methenamine silver stain in the diagnosis of pneumocystis peumonia (PCP).Methods 2 525 unrepeated specimens from suspected PCP patient admitted in Peaking Union Medical College Hospital were collected in 2014.2 492 samples were detected by gomori-methenamine silver stain,33 samples were detected by real-time PCR,and 429 samples were detected by both methods at the meanwhile.With clinical diagnosis as reference standard,the sensitivity,specificity,positive predictive value and negative predictive value of the two methods were analysised.Results Positive rate of gomori-methenamine silver stain was 1.2 ％ (30/2 492).The first three specimen types were sputum,tracheal intubation suction and bronchoalveolar lavage fluid,the positive rate was 0.70 ％ (13/1 845),4.00％ (10/250) and 2.72％ (7/257) respectively.Positive rate of realtime PCR was 34.20％ (158/462),and the positive rate of sputum and bronchoalveolar lavage fluid was 30.61％ (105/343) and 44.54％ (53/119) respectively.The sensitivity were 13.97％ vs 72.07％,specificity were 100％ vs 94.24％,positive predictive value were 100％ vs 92.14％ and negative predictive value were 55.36％ vs 78.26％ for gomori-methenamine silver stain and real-time PCR respectively.All of which were statistically significant analysed by x2 test for paired data.The x2 value and P alue were x2 =68.625,P＜0.01;x2 =4.296,P＜0.05;x2 =6.380,P＜0.01 and x2 =11.873,P＜0.01.Conclusion The real-time PCR had higher sensitivity,fewer interference factors and more clinical diagnostic value,so clinicians should make more use of real-time PCR to diagnose PCP earlier.

Mosquitoes of Western Yunnan Province, China: seasonal abundance, diversity, and arbovirus associations.

OBJECTIVE: The western borderland between Yunnan Province, China, and Myanmar is characterized by a climate that facilitates year-round production of mosquitoes. Numerous mosquito-transmitted viruses, including Japanese encephalitis virus circulate in this area. This project was to describe seasonal patterns in mosquito species abundance and arbovirus activity in the mosquito populations. METHODS: Mosquitoes were collected in Mangshi and Ruili cities of Dehong Prefecture near the border of China and Burma in Yunnan Province, the Peoples Republic of China in 2010. We monitored mosquito species abundance for a 12-month period using ultraviolet light, carbon dioxide baited CDC light and gravid traps; and tested the captured mosquitoes for the presence of virus to evaluate mosquito-virus associations in rural/agricultural settings in the area. RESULTS: A total of 43 species of mosquitoes from seven genera were collected, including 15 Culex species, 15 Anopheles spp., four Aedes spp., three Armigeres spp., one Mimomyia spp., two Uranotaenia spp. and three Mansonia spp.. Species richness and diversity varied between Mangshi and Ruili. Culex tritaeniorhynchus, Culex quinquefasciatus, Anopheles sinensis and Anopheles peditaeniatus were the most abundant species in both sampling sites. Ultraviolet light traps collected more specimens than CDC light traps baited with dry ice, though both collected the same variety of mosquito species. The CDC gravid trap was the most effective trap for capture of Culex quinquefasciatus, a species underrepresented in light trap collections. A total of 26 virus strains were isolated, which included 13 strains of Japanese encephalitis virus, four strains of Getah virus, one strain of Oya virus, one strain from the orbivirus genus, and seven strains of Culex pipien pallens densovirus. CONCLUSIONS: The present study illustrates the value of monitoring mosquito populations and mosquito-transmitted viruses year-round in areas where the climate supports year-round adult mosquito activity.

[An outbreak of imported dengue fever from Myanmar to the border of China, with its viral molecular epidemiological features].

OBJECTIVE: To understand the epidemiologic characteristics of dengue fever, imported from Myanmar to the border of Yunnan province, China. Viral molecular epidemiologic features were also studied. METHODS: Questionnaires were used on each diagnosed, suspected dengue fever, case or unknown cases with fever when coming from Myanmar entering the port and hospitals in Ruili city of Yunnan province. Serum samples of these patients were collected to detect IgM antibody against dengue virus and RT-PCR assay. Homology and phylogenetic tree based on the whole nucleotide sequence of PrM-C and NS5 gene of dengue virus were further analyzed. RESULTS: A total of 103 sera were collected from patients at acute stage in Ruili city in July to November 2008. Among them, 49 cases were confirmed for dengue fever according to IgM and nucleic acid testings. Except one, other 48 cases were all imported into Ruili, from Myanmar. Of those, 18 patients were residents from Mujie city of Myanmar and hospitalized in Ruili and the rest 30 patients were Chinese citizens who had finished business and returned from Myanmar. Two isolates of serum samples from the imported cases were identified and both homology and phylogenetic analysis were performed, using the nucleotide sequences of PrM and NS5 genes. They were divided into dengue type 1 (RLB61) and dengue type 3 (RLC31) and were closer to the dengue virus strains isolated from Southeast Asia countries. CONCLUSION: It is confirmed that an epidemic of dengue fever which was imported from Myanmar to Ruili city of Yunnan province, China. Evidence also showed that both type I and III epidemic strains of dengue virus did exist in Mujie city of Myanmar in 2008.