Sir,
Amyloidosis with skin involvement can be classified as localized cutaneous amyloidosis and cutaneous manifestation of systemic amyloidosis. Systemic amyloidosis can be presented as Primary systemic amyloidosis or amyloid light-chain (AL) amyloidosis due to plasma cell dyscrasias and Secondary systemic amyloidosis or AA (amyloid A protein) amyloidosis due to chronic inflammatory diseases. In AL amyloidosis, mostly lambda light chain immunoglobulin accumulates. Skin manifestations are generally located on periorbital area, neck and skin folds. Waxy papules and plaques, yellowish nodules and purpura, and ecchymosis can be seen due to amyloid accumulation in vessel walls.[1,2] A 68-year-old male patient presented with a striking yellowish colour change in his skin for 1 year. He had hypertension, gout and benign prostate hyperplasia in his medical history. A dermatologist had made a diagnosis of carotenemia (xanthoderma) and advised the patient to avoid excessive consumption of carotene-rich foods 1 year ago. Dermatologic examination revealed bilaterally localized purpuric yellow plaques on his neck, periorbital, axillary and inguinal regions [Figure 1a and b]. On dermoscopy, yellowish, whitish and purplish-red homogeneous areas were seen [Figure 2a and b]. A cutaneous biopsy was performed with a pre-diagnosis of systemic amyloidosis, carotenemia, xanthoma and dermatomyositis. Jaundice was easily excluded due to normal serum bilirubin levels. Histopathological examination revealed eosinophilic amorphous material at the dermis and at the vessel walls. This amorphous material which was positive with Congo red stain and under polarization light exhibiting apple green birefringence was found to be amyloid. Amyloid deposits were also seen at the peri-adnexal area, and it was negative with serum A amyloid and positive with C4d immunohistochemically [Figure 3a–f]. Proteinuria was detected as 4.41 g in 24-h urine examination. Serum kappa and lambda light chains were increased with levels 22.5 mg/L and 350 mg/L, respectively. The patient was referred to the haematology department, and the diagnosis of multiple myeloma was made with bone marrow aspiration and biopsy.
Figure 1.
(a and b) Petechia, purpura and yellowish discolouration over periorbital and axillary region
Figure 2.
(a and b) Homogeneous purplish-red, yellowish and whitish areas were seen on dermoscopy
Figure 3.
(a to f) Amyloid deposits at the dermis and at the vessel walls (a: H and E × 40, b: H and E ×100, c–d: Congo red and polarization × 100, e–f: thioflavin T and fluorescence ×100)
The initial manifestation of AL amyloidosis in this patient was yellow discolouration of the skin, and unfortunately, the diagnosis of amyloidosis could not be made before 1 year. The aetiology of AL amyloidosis in this patient was multiple myeloma. Plasma cells produce the accumulated light chain immunoglobulins and their fragments. In AL amyloidosis besides skin, many organs such as kidneys, heart, peripheral nerves and liver can be affected. While skin involvement is very rare in AA amyloidosis, skin findings can be seen up to 20–40% in AL amyloidosis.[3] Dermoscopic findings in cutaneous involvement of AL amyloidosis were reported as yellowish surface,[4,5] pinpoint petechia,[4] homogeneous purpuric surface, yellow areas and white scar-like area.[5] We also observed purplish-red petechial, yellowish and whitish areas on dermoscopy. Cutaneous findings in AL amyloidosis with dermoscopic features are rarely reported in the literature. Dermoscopy aids when cutaneous involvement of systemic amyloidosis is slight and raises the suspicion for systemic amyloidosis to canalize the clinician for biopsy.
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References
- 1.Groves RW. Amyloidosis. In: Bolognia JL, Schaffer JV, Cerroni L, editors. Dermatology. 4th ed. Elsevier; 2018. pp. 754–63. [Google Scholar]
- 2.Gontijo JRV, Pinto JM, Paula MC. Case for diagnosis. Systemic light chain amyloidosis with cutaneous involvement. An Bras Dermatol. 2017;92:731–2. doi: 10.1590/abd1806-4841.20176958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Vyas K, Morgaonkar M, Gupta S, Jain SK. Primary systemic amyloidosis with unusual dermatological manifestations: A rare case report. Indian J Dermatol. 2016;61:216–8. doi: 10.4103/0019-5154.177767. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Hu SC, Chen GS, Yang SF, Wu CY. Dermoscopy as a diagnostic aid in a case of systemic amyloidosis with initial presentation in skin. J Dermatol. 2015;42:1201–2. doi: 10.1111/1346-8138.13103. [DOI] [PubMed] [Google Scholar]
- 5.Jung JH, Kwon DI, Seong SH, Lee KH, Suh KS, Jang MS, et al. Usefulness of dermoscopy in identifying amyloid purpura. J Dermatol. 2021;48:e260–2. doi: 10.1111/1346-8138.15854. [DOI] [PubMed] [Google Scholar]
