Primary localized cutaneous amyloidosis: a clinicopathologic study from Saudi Arabia

Area of Science:

• Dermatology
• Pathology
• Medical Research

Background:

• Primary localized cutaneous amyloidosis (PLCA) involves amyloid deposition in normal-appearing skin without systemic involvement.
• Certain ethnic groups exhibit a predisposition to PLCA.
• The study aimed to assess PLCA occurrence and review clinico-pathologic findings.

Purpose of the Study:

• To determine the incidence of PLCA in a hospital setting.
• To analyze the clinical and pathological features of confirmed PLCA cases.
• To review diagnostic criteria and differentiating features between subtypes.

Main Methods:

• Retrospective analysis of patient records and skin biopsy paraffin sections.
• Inclusion of cases clinically diagnosed as cutaneous amyloidosis from 1987-1995.
• Histological confirmation of amyloid deposits in skin biopsies.

Main Results:

• 21 out of 42 suspected cases were confirmed as PLCA (0.15% of 920 biopsied patients).
• Lichen amyloidosis (LA) accounted for 11 cases, and macular amyloidosis (MA) for 10 cases.
• Epidermal changes were key histological differentiators between LA and MA; women predominated in MA.

Conclusions:

• PLCA is a rare, chronic, progressive skin condition in adults.
• Prevalence in this Saudi Arabian tertiary care hospital dermatology clinic was 0.15%.
• Histological examination, potentially including sequential biopsies, is crucial for diagnosis.