case_images: PMC11039820_01
case_images: Hyperpigmentation of head, face, neck, upper limbs and lower limbs.
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case_images: f1
case_images: Our physical examination revealed excessive skin pigmentation in many parts of the body, especially in the head and face, neck, upper limbs and lower limbs ( Figure 1 ).
case_images: (A) OCT results of the right eye; (B)  OCT results of the left eye.
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case_images: f2
case_images: Therefore, we performed optical coherence tomography (OCT) ( Figure 2 ) and fundus screening ( Figures 3A-D ) on the patient. The macular morphology was irregular, and the thickness of the macular fovea was significantly thinner ( Figure 2A ). However, the results of OCT of the left eye did not show any significant abnormality ( Figure 2B ).
case_images: (A)  Right anterior segment findings; (B) Right eye fundus screening results; (C) Left anterior segment findings; (D) Left eye fundus screening results.
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case_images: f3
case_images: Therefore, we performed optical coherence tomography (OCT) ( Figure 2 ) and fundus screening ( Figures 3A-D ) on the patient.
case_images: (A) HE staining; (B) Fontana-Masson staining; (C) Prussian blue staining; (D) silver hexamine staining.
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case_images: HE staining ( Figure 4A ) showed excessive keratinization of the epidermal mesh basket, a significant increase in melanin in the basal layer, sparse lymphocyte and tissue cell infiltration around the blood vessels in the superficial dermis, and a few melanocytes and melanin granules were seen locally, considering drug-induced pigmentation. Fontana-Masson staining ( Figure 4B ) showed a significant increase in melanin in the basal layer of the epidermis and a few melanin granules in the superficial dermis. Figures 4C, D ). Five items of direct immunofluorescence ( Figure 5 ) C3, IgG, IgM, IgA and Fib were all negative.
case_images: Direct immunofluorescence staining.
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case_images: f5
case_images: Figures 4C, D ). Five items of direct immunofluorescence ( Figure 5 ) C3, IgG, IgM, IgA and Fib were all negative.