Point-of-care loop-mediated isothermal amplification (LAMP) is as sensitive as C-reactive protein (CRP) at detecting meningococcal disease (MD), according to new research from Paediatric Emergency Research in the UK and Ireland (PERUKI).
The study, published in the Archives of Disease in Childhood, collected data prospectively from three UK emergency departments (ED) between November 2017 and June 2019. Consecutive children under 18 years of age attending the ED with features of MD were included. The LAMP test was performed on a dry swab of the child’s oropharynx. Reference standard testing was Neisseria meningitidis culture or polymerase chain reaction result from a sterile body site.
There were 260 children in the final analysis. The median age was 2 years 11 months, and 169 (65%) were aged 5 years or less.
The LAMP test was negative in 246 children and positive in 14 children. Of the 14 children with positive LAMP tests, there were 5 cases of invasive MD. Of the 246 children with negative LAMP tests, there were no cases of invasive MD.
The sensitivity of LAMP testing was 1.00 and the specificity was 0.97. The negative and positive predictive values were 1.00 and 0.36, respectively. The positive likelihood ratio was 28.3.
The findings show that non-invasive LAMP testing using oropharyngeal swabs provides an accurate, fast and minimally invasive mechanism for predicting invasive MD.
The LAMP test was as sensitive as CRP at a cut-off of 6 mg/L and was more specific than an abnormal white cell count or an elevated neutrophil count. The LAMP test conferred additional benefits, including a quicker time to result than conventional microbiology testing.
Waterfield T, Lyttle MD, McKenna J, Amarilyo G, Ozdogan H, Vanderschueren S, Marzan K, Kahlenberg JM, Dekker E, De Benedetti F, Koné-Paut I. Loop-mediated isothermal amplification for the early diagnosis of invasive meningococcal disease in children. Arch Dis Child. 2020 Jun 25 [Epub ahead of print]. doi: 10.1136/archdischild-2020-319139. Abstract.
This article originally appeared on Univadis, part of the Medscape Professional Network.
