Low Sensitivity of a Nested Polymerase Chain Reaction in Oropharyngeal Washings for the Diagnosis of Pneumocystis Pneumonia in HIV-Infected Patients

CHEST Journal ◽  
2005 ◽  
Vol 128 (1) ◽  
pp. 167-171 ◽  
Author(s):  
Kennedy Nyamande ◽  
Umesh G. Lalloo ◽  
Dennis York ◽  
Mogambal Naidoo ◽  
Elvis M. Irusen ◽  
...  
2013 ◽  
Vol 18 (3) ◽  
Author(s):  
Martha Grecca ◽  
Vanete Thomaz-Soccol ◽  
Magda C Costa Ribeiro ◽  
Jessé Henrique Truppel ◽  
Juliana Tracz Pereira ◽  
...  

The present study was carried out with the aim of assess the occurrence of Cryptosporidium sp. infection in dogs and cats in Curitiba and its metropolitan area, state of Paraná, Brazil. Techniques employed to detect the protozoan in fecal samples were: staining by Ziehl-Neelsen for oocysts search and nested polymerase chain reaction (nPCR) targeting the 18SSU rDNA gene. To attempt the proposed aim, 91 feces samples of dogs and 25 of cats were collected and analyzed. Ziehl-Neelsen technique was unable to detect any oocyst in both groups analyzed, showing a very low sensitivity. Results of nPCR showed an infection rate of 13.2% (12/91) and 4% (1/25) in dogs and cats respectively.  The implications of these epidemiological data are discussed in this work.


2006 ◽  
Vol 52 (8) ◽  
pp. 747-752 ◽  
Author(s):  
Sandra Denize Dorneles Jouglard ◽  
Simone Simionatto ◽  
Fabiana Kommling Seixas ◽  
Fernanda Lima Nassi ◽  
Odir Antônio Dellagostin

Leptospirosis is a widespread zoonosis caused by pathogenic members of the genus Leptospira that has a great impact on human and veterinary public health. Early diagnosis of leptospirosis is important because severe lepto spiral infection can have a fulminant course. The available serological techniques for the diagnosis of leptospirosis have low sensitivity during the early stage of the disease. Efforts are being made to develop simpler, effective, efficient, and inexpensive diagnostic methods. In this work, we first evaluate a polymerase chain reaction (PCR) based method for diagnosis of leptospirosis. Primers were designed to amplify a 264 bp region within the lipL32 gene that is conserved among pathogenic Leptospira and absent in nonpathogenic species. The sensitivity and specificity of the assay were evaluated using 7 saprophytic serovars, 37 pathogenic serovars, and 15 other microorganisms. The method was very specific for pathogenic serovars, however, it lacked sensitivity. To enhance the sensitivity, another primer pair was designed to amplify a 183 bp region within the 264 bp region of the lipL32 gene and was used in a nested PCR assay. This approach was much more sensitive than conventional PCR.Key words: leptospirosis, diagnosis, nested PCR, lipL32.


2014 ◽  
Vol 104 (3) ◽  
pp. 233-237 ◽  
Author(s):  
María José Iglesias Sánchez ◽  
Ana María Pérez Pico ◽  
Félix Marcos Tejedor ◽  
María Jesús Iglesias Sánchez ◽  
Raquel Mayordomo Acevedo

Background Dermatomycoses are a group of pathologic abnormalities frequently seen in clinical practice, and their prevalence has increased in recent decades. Diagnostic confirmation of mycotic infection in nails is essential because there are several pathologic conditions with similar clinical manifestations. The classical method for confirming the presence of fungus in nail is microbiological culture and the identification of morphological structures by microscopy. Methods We devised a nested polymerase chain reaction (PCR) that amplifies specific DNA sequences of dermatophyte fungus that is notably faster than the 3 to 4 weeks that the traditional procedure takes. We compared this new technique and the conventional plate culture method in 225 nail samples. The results were subjected to statistical analysis. Results We found concordance in 78.2% of the samples analyzed by the two methods and increased sensitivity when simultaneously using the two methods to analyze clinical samples. Now we can confirm the presence of dermatophyte fungus in most of the positive samples in just 24 hours, and we have to wait for the result of culture only in negative PCR cases. Conclusions Although this PCR cannot, at present, substitute for the traditional culture method in the detection of dermatophyte infection of the nails, it can be used as a complementary technique because its main advantage lies in the significant reduction of time used for diagnosis, in addition to higher sensitivity.


1992 ◽  
Vol 37 (4) ◽  
pp. 310-314 ◽  
Author(s):  
Richard Sallie ◽  
Anne Rayner ◽  
Bernard Portmann ◽  
A. L. W. F. Eddleston ◽  
Roger Williams

2004 ◽  
Vol 50 (6) ◽  
pp. 415-421 ◽  
Author(s):  
J Guan ◽  
J L Spencer ◽  
M Sampath ◽  
J Devenish

The fate of the genetically modified (GM) Pseudomonas chlororaphis strain 3732 RN-L11 and its transgene (lacZ insert) during composting of chicken manure was studied using plate count and nested polymerase chain reaction (PCR) methods. The detection sensitivity of the nested PCR method was 165 copies of the modified gene per gram of moist compost or soil. Compost microcosms consisted of a 100-g mixture of chicken manure and peat, whereas soil microcosms were 100-g samples of sandy clay loam. Each microcosm was inoculated with 4 × 1010CFU of P. chlororaphis RN-L11. In controlled temperature studies, neither P. chlororaphis RN-L11 nor its transgene could be detected in compost microcosms after incubation temperature was elevated to 45 °C or above for one or more days. In contrast, in the compost microcosms incubated at 23 °C, the target organism was not detected by the plate count method after 6 days, but its transgene was detectable for at least 45 days. In compost bins, the target organism was not recovered from compost microcosms or soil microcosms at different levels in the bins for 29 days. However, the transgene was detected in 8 of the 9 soil microcosms and in only 1 of the 9 compost microcosms. The compost microcosm in which transgene was detected was at the lower level of the bin where temperatures remained below 45 °C. The findings indicated that composting of organic wastes could be used to reduce or degrade heat sensitive GM microorganisms and their transgenes.Key words: composting, genetically modified Pseudomonas strain, transgene, polymerase chain reaction.


2008 ◽  
Vol 23 (3) ◽  
pp. 243-245 ◽  
Author(s):  
Divya Mahajan ◽  
Anju Jain ◽  
Varsha Singh ◽  
A. K. Jain ◽  
G. R. K. Rao ◽  
...  

2018 ◽  
Vol 47 (1) ◽  
pp. 146-149 ◽  
Author(s):  
Ayeley A. K. Okine ◽  
Seth Chapman ◽  
Roger A. Hostutler ◽  
Robert Livingston

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