Diagnostic Performance of Schistosoma Real-Time PCR in Urine Samples from Kenyan Children Infected with Schistosoma haematobium: Day-to-day Variation and Follow-up after Praziquantel Treatment

Autor: Eric A. T. Brienen, Birgitte J. Vennervald, Govert J. van Dam, David Shaproski, Lisette van Lieshout, Anthony I. Kahama, Natalie V. S. Vinkeles Melchers
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Male
Epidemiology
Physiology
Urine
Global Health
Praziquantel
law.invention
Schistosomiasis haematobia
law
Medicine and Health Sciences
Schistosomiasis
Public and Occupational Health
Child
Polymerase chain reaction
Schistosoma haematobium
Anthelmintics
Microscopy
biology
lcsh:Public aspects of medicine
Real-time polymerase chain reaction
Infectious Diseases
Helminth Infections
Female
Drug Monitoring
medicine.drug
Research Article
Neglected Tropical Diseases
lcsh:Arctic medicine. Tropical medicine
Adolescent
lcsh:RC955-962
Real-Time Polymerase Chain Reaction
Sensitivity and Specificity
Infectious Disease Epidemiology
Diagnostic Medicine
Predictive Value of Tests
parasitic diseases
DNA
Ribosomal Spacer

medicine
Parasitic Diseases
Animals
Humans
Schistosoma
Retrospective Studies
Public Health
Environmental and Occupational Health

lcsh:RA1-1270
biology.organism_classification
medicine.disease
Tropical Diseases
Kenya
Parasitology
Immunology
Zdroj: PLoS Neglected Tropical Diseases, 8(4)
PLoS Neglected Tropical Diseases
Vinkeles Melchers, N V S, van Dam, G J, Shaproski, D, Kahama, A I, Brienen, E A T, Vennervald, B J & van Lieshout, L 2014, ' Diagnostic performance of Schistosoma real-time PCR in urine samples from Kenyan children infected with Schistosoma haematobium : day-to-day variation and follow-up after praziquantel treatment ', P L o S Neglected Tropical Diseases
, vol. 8, no. 4, e2807 . https://doi.org/10.1371/journal.pntd.0002807
PLoS Neglected Tropical Diseases, Vol 8, Iss 4, p e2807 (2014)
DOI: 10.1371/journal.pntd.0002807
Popis: Background In an effort to enhance accuracy of diagnosis of Schistosoma haematobium, this study explores day-to-day variability and diagnostic performance of real-time PCR for detection and quantification of Schistosoma DNA compared to other diagnostic tools in an endemic area before and after treatment. Methodology Previously collected urine samples (N = 390) from 114 preselected proven parasitological and/or clinical S. haematobium positive Kenyan schoolchildren were analyzed by a Schistosoma internal transcribed spacer-based real-time PCR after 14 years of storage. Pre-treatment day-to-day fluctuations of PCR and microscopy over three consecutive days were measured for 24 children using intra-class correlation coefficient. A combined ‘gold standard’ (PCR and/or microscopy positive) was used to measure sensitivity and negative predictive value (NPV) of several diagnostic tools at baseline, two and 18 months post-treatment with praziquantel. Principal Findings All 24 repeatedly tested children were PCR-positive over three days with little daily variation in median Ct-values, while 83.3% were found to be egg-positive for S. haematobium at day 1 and 75.0% at day 2 and 3 pre-treatment, signifying daily fluctuations in microscopy diagnosis. Of all 114 preselected schoolchildren, repeated microscopic measurements were required to detect 96.5% versus 100% of positive pre-treatment cases by single PCR. At two months post-treatment, microscopy and PCR detected 22.8% versus 69.3% positive children, respectively. Based on the ‘gold standard’, PCR showed high sensitivity (>92%) as compared to >31% sensitivity for microscopy, both pre- and post-treatment. Conclusions/Significance Detection and quantification of Schistosoma DNA in urine by real-time PCR was shown to be a powerful and specific diagnostic tool for detection of S. haematobium infections, with less day-to-day variation and higher sensitivity compared to microscopy. The superior performance of PCR before, and two and 18 months post-treatment provides a compelling argument for PCR as an accurate and reproducible tool for monitoring treatment efficacy.
Author Summary Schistosoma haematobium is a blood fluke that causes severe urogenital pathology and affects millions of people, mainly in sub-Sahara Africa. Current diagnosis is based on microscopic examination of urine samples, but this method is not only observer dependent, but also known for its low sensitivity and high day-to-day variability. Accurate diagnosis is important to assess community levels of infections for consideration of deworming campaigns, and to monitor treatment efficacy. We evaluated a real-time polymerase chain reaction (PCR) assay for specific detection and quantification of Schistosoma DNA in urine samples from 114 preselected S. haematobium infected schoolchildren of endemic coastal Kenya and compared the outcome to several other diagnostic methods. Three urine samples collected over three subsequent days from 24 participants were used for Analyzing day-to-day fluctuations in egg counts and Schistosoma DNA levels. Urine was also tested two and 18 months after praziquantel treatment. Compared to microscopy, we observed less day-to-day fluctuations and higher sensitivity with real-time PCR, in particular when tested two months after therapy. Real-time PCR is therefore useful for more accurate identification of S. haematobium, especially in monitoring control interventions.
Databáze: OpenAIRE