Podoconiosis: Clinical spectrum and microscopic presentations

BackgroundPodoconiosis is a skin Neglected Tropical Disease (skin NTD) that causes lymphoedema, and affects barefooted subsistence farmers in some tropical countries. The clinical presentation and histopathologic correlates of podoconiosis have been understudied. Here, we systematically document the clinical and histopathologic spectrum of podoconiosis. MethodsThis is a cross-sectional study in Durbete, Ethiopia from February 2018 to October 2019. Dermatologists performed a patient history, physical examination, filariasis test strip, and skin biopsy for histopathologic examination. The results were summarised and a descriptive statistical analysis and Wilcoxon rank sum test with continuity correction was done. ResultsWe recruited 289 patients for the study, 178 (61.6%) had stage 1 or 2 podoconiosis, and 111(38.4%) stage 3 to 5 podoconiosis. 188 (64.1%) had a family history of podoconiosis. In 251 (86.9%) patients, both legs were affected by podoconiosis and in 38 (13.1%) only one leg was affected. 220 (77.5%) patients had warty lesions, 114 (39.4%) had nodules. The median number of episodes of Acute Dermato-Lymphangio-Adenitis (ADLA) reported by the patients in the last three months was 2 (interquartile range (IQR) 1-4). Increased episodes of ADLA were significantly associated with stage 3-5 podoconiosis (P = 0.002), while burning pain in the feet was more common in stage 1 or 2 podoconiosis. Stage 3-5 disease was histopathologically characterised by epidermal and dermal thickening, verrucous acanthosis, inflammatory cell infiltrates (predominantly lymphoplasmacytic), dilated and ectatic and a reduced number of lymphatic vessels, eccrine ductal hyperplasia, and sclerosis such as thickened collagen bundles. ConclusionWe provide a detailed description of the different clinical patterns, associated clinical findings and the histopathologic spectrum of podoconiosis at different stages of the disease. Our observations should serve as a guide to classifying patients with podoconiosis for prognostic assessment and treatment decision. Author summaryPodoconiosis is a skin Neglected Tropical Disease (skin NTD) that causes swelling of the lower extremities. The disease affects barefooted subsistence farmers in some tropical countries. It is caused by destruction of the lymphatic system in the legs, which is critical for the transportation of body fluids. Podoconiosis is physically disabling with significant psycho-social impact.In Ethiopia alone more than 1.5 million people are affected by podoconiosis. The past 50 to 60 years generated substantial evidence on the disease distribution, genetic influence, psycho-social impact and clinical management. Yet, systematic information about the various clinical manifestations and histopathologic features of podoconiosis is sparse. We therefore recorded in 289 podoconiosis patients their history, and disease-related findings of the lower extremities. We also took blood and tissue samples for laboratory examination. In summary, this study provides a description of the different clinical manifestations and microscopic tissue findings of various podoconiosis stages from mild to advance. Our observations are a guide to classifying patients with podoconiosis, based on clinical and microscopic tissue definitions. Classification can help in patient management, therapeutic follow-up, prioritisation of resources, epidemiological surveillance and future research to improve the quality of life of patients with podoconiosis.

Automated summary

This study provides a detailed description of the clinical and histopathologic spectrum of podoconiosis at different stages of the disease. The observations can serve as a guide for classifying patients with podoconiosis for prognostic assessment and treatment decision.