Current knowledge for the microbiological diagnosis of Tropheryma whipplei infection

ABSTRACT Introduction Whipple's disease is a rare clinical entity that is usually fatal if left untreated.Tropheryma whippleiwas first cultured 20 years ago, and has led to the development of diagnostic tools that have greatly improved knowledge of the disease. T. whipplei is actually more common than initially described with the description of common asymptomatic carriage. Areas covered We reviewed current knowledge of microbiological diagnosis and summarized the diagnostic strategy ofT. whipplei infection. Articles were selected from Medline and Google scholar using the keywords ‘Tropheryma whipplei’ OR ‘Whipple’s disease’ AND ‘diagnosis’. Expert opinion Definitive diagnosis of Whipple’s disease is challenging and continues to be based on immunohistochemical analysis or PAS staining combined with positive qPCR on duodenal biopsy. Initially, screening forT. whipplei was recommended on stool and saliva which are associated with a high positive predictive value of Whipple’s disease. However, given the presence of a large number of asymptomatic carriers, the specificity of a positive qPCR on these samples is likely to have decreased and their interests should be reevaluated. The development of new noninvasive tests may be useful for the diagnosis of Whipple’s disease and qPCR performed on urine could be a promising alternative.