case_images: PMC11045939_01
case_images: Clinical presentation of the patient. (A, B) infiltrated dark red plaques distributed across the right lower extremity, overlaying discrete circular superficial ulcers characterized by a lack of exudation.
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case_images: f1
case_images: Upon physical examination, the clinical presentation revealed dark red plaques distributed across the right lower extremity, overlaying discrete circular superficial ulcers characterized by a lack of exudation ( Figure 1 ).
case_images: Histopathological features of the biopsy. (A, B) the presence of necrotizing granulomas with variable lymphocytic infiltration, as demonstrated by hematoxylin-eosin staining. (C-F) Immunohistochemical staining showed a significant proportion of the infiltrating cells located at the granuloma center exhibited CD68 positivity, indicative of macrophages. Surrounding these macrophages were T lymphocytes, notably positive for both CD4 and CD8.[original magnification x40 in A, x200 in B, and x40 for all images in (C-F)].
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case_images: PMC11045939_01_fimmu-15-1366840-g002.jpg
case_images: f2
case_images: The overall granulomatous patterns exhibited a palisaded, sarcoidal, and suppurative nature with caseation ( Figures 2A, B ). Immunohistochemistry results indicated that the predominant infiltrating cells within the granuloma were CD4+/CD8+ positive lymphocytes and CD68+/CD163+ macrophages ( Figures 2C-F ).
case_images: The metagenomic next-generation sequencing (mNGS) test result. The metagenomic next-generation sequencing (mNGS) test identified a total of 368 reads corresponding to rubella virus, with a coverage of 61.9033%.
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case_images: f3
case_images: The test identified a total of 368 reads corresponding to rubella virus, with a coverage of 61.9033% ( Figure 3 ).
case_images: The Whole Exome Sequencing Testing result. The Whole Exome Sequencing Testing reveals a homozygous mutation NM_000593.5:c.1151C>G (p.Ser384*) located in TAP1.
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case_images: PMC11045939_01_fimmu-15-1366840-g004.jpg
case_images: f4
case_images: Given the possibility of an underlying immunodeficiency, Whole Exome Sequencing was undertaken, revealing a homozygous mutation NM_000593.5:c.1 151C>G (p.Ser384*) located in TAP1 ( Figure 4 ;  Supplementary Data 1 ), which was verified by Sanger Sequencing.