First report on clinical diversity within classical cutaneous Leishmaniasis: parasite or host related?

Abstract

Introduction: We have previously reported a changing micro-profile within classical cutaneous leishmaniasis (CCL) and presence of different epidemiological foci in Northern (NR) and Southern regions (SR) in Sri Lanka. Current project aimed at further examining the nature of clinical diversity of CCL. Methods: Patients with laboratory confirmed CCL (n=550) from NR or SR were evaluated. Results: Rate and course of lesion progression were different in the two foci. NR reported a slow progression in lesion development with low tendency for lesion ulceration, enlargement and multiplication while SR reported a rapid progression. At a given duration, most lesions started ulceration in SR [early lesions (≤3 months): 55.6% and late lesions (>3 months): 56.9%] than in NR (early: 29.8%, late: 37.7%). Also, enlarged lesions (>2 cm) were markedly higher in SR (early: 42.7%, late: 50.0%) than in NR (early: 21.1%, late: 34.9%). Only a small proportion of lesions showed multiplication (>1 lesions) both in SR (early: 5.8%, late: 6.9%) and NR (early: 26.3%, late: 28.3%). This study shows evidence for wider individual variation in the pattern of progression of a skin lesion. All different types, sizes and both single and multiple lesions were seen at any given duration. Parasitic or a host aetiology could explain observed differences. In addition, laboratory detection rate declined significantly when lesions multiplied and enlarged. Conclusions: These findings need to be considered in clinical screening in each region and for disease control efforts. Small, papular, non-painful and non-tender lesions can often remain unnoticed while being parasite reservoirs in a community. Awareness is important in these regions. Study also provided indicating evidence for an underlying parasitic or a host aetiology. These findings can now be applied in patient care, epidemiological work and in further studies.