A Case Report of Lichen Amyloidosis

Lichen amyloidosis (LA) is a primary localized cutaneous amyloidosis that closely resembles other chronic dermatological disorders, potentially delaying diagnosis.We report the case of a 60-year-old man with hypertension and chronic kidney disease who was admitted in 2020 with left leg pain and swelling.Investigations ruled out deep vein thrombosis, while CT revealed diffuse subcutaneous edema.Cellulitis was suspected, and the patient was subsequently discharged with analgesia and outpatient follow-up with vascular surgery and dermatology.From 2021 onward, his symptoms were attributed to stasis eczema and lymphedema.Clinical examination revealed multiple hyperpigmented papules on the left lower limb, with additional involvement of the upper back, trunk, and arms.Laboratory investigations showed an eosinophil count of 20.2%, baseline creatinine levels, and normal electrolyte and liver function tests.Due to persistent symptoms, a skin biopsy was obtained from a lesion on the lower back.Histopathological examination revealed hyperkeratosis, acanthosis, elongated rete ridges, increased melanin deposition, and superficial perivascular lymphohistiocytic infiltrates with melanophages.Amyloid globules within the widened papillary dermis stained positively with Congo red, confirming the diagnosis of LA.This case highlights how LA may be misdiagnosed as stasis eczema or lymphedema for years.LA should be considered in patients presenting with persistent hyperpigmentation and papular eruptions involving the lower limbs.