Impact of PCR on the diagnosis and management of cutaneous Leishmaniasis from paraffin-embedded samples.

INTRODUCTION

Leishmaniasis is a group of diseases caused by Leishmania spp., transmitted by sandflies, in Europe and surrounding areas. The diagnosis of cutaneous Leishmaniasis (CL) presents challenges both in sample collection and in the accuracy of diagnostic techniques, which hinders its confirmation. The objective of this study is to determine the diagnostic performance of molecular techniques applied to formalinfixed, paraffin-embedded (FFPE) skin biopsy samples, and their value as a complementary tool in the diagnosis of CL, especially in patients for whom other clinical samples are unavailable.

METHODS

A retrospective descriptive study (January 2019-November 2025) was conducted at the Virgen de la Arrixaca University Hospital (Murcia, Spain) that included 77 paraffin-embedded samples.

RESULTS

25 samples (32.5%) were positive by Polymerase Chain Reaction, with a presumptive diagnosis of cutaneous leukemia (CL) by primary care in 11 samples, and a differential diagnosis with reactive inflammatory processes in 14 samples. 72% (18/25) had received inadequate prior treatment.

CONCLUSION

PCR in FFPE samples is an excellent complementary tool that improves the diagnosis of CL.