The evaluation of IgG4 and IgG expression in cutaneous Rosai-Dorfman disease

Abstract Objective The authors investigated the expression of IgG4 and IgG in cutaneous Rosai-Dorfman Disease (CRDD) to further improve the understanding of this disease. Methods The authors retrospectively reviewed the clinicopathological features of 23 CRDD patients. The authors diagnosed CRDD by the presence of emperipolesis and immunohistochemical (IHC) staining of histiocytes consisting of S-100(+)/CD68(+)/CD1a(-) cells. The expressions of IgG and IgG4 in cutaneous specimens were assessed by IHC (EnVision) and quantitatively calculated by a medical image analysis system. Results All 23 patients, including 14 males and 9 females, were confirmed to have CRDD. Their ages ranged from 17 to 68 years (mean 47.91 ± 14.16). The most frequently affected skin regions were the face, followed by the trunk, ears, neck, limbs, and genitals. In 16 of these cases, the disease presented as a single lesion. IHC staining of sections showed that IgG was positive (≥ 10 cells/High-Power Field [HPF]) in 22 cases, while IgG4 was positive (≥ 10 cells/HPF) in 18 cases. Moreover, the IgG4/IgG proportion ranged from 1.7% to 85.7% (mean 29.50 ± 24.67%, median 18.4%) in the 18 cases. Study limitations In the majority of studies, as well as in the current study, the design. RDD is a rare disease, so the sample size is small. In the next studies to come, the authors will expand the sample for multi-center verification and in-depth study. Conclusion The positive rates of IgG4 and IgG and the IgG4/IgG ratio assessed through IHC staining may be important in understanding the pathogenesis of CRDD.

Vulvar ulcerative cutaneous tuberculosis secondary to genital tract tuberculosis

Abstract Tuberculosis is a chronic infectious disease that gradually poses a certain threat to public health and economic growth. Tuberculosis typically affects the lungs, pleura, and lymph nodes and rarely the skin. Cutaneous tuberculosis manifesting as ulcerated lesions is also rare and often misdiagnosed and missed by clinicians. Here, the authors report a 29-year-old female patient presenting a vulvar ulcer for 10 months, accompanied by irregular menstruation and increased vaginal secretions. After a skin biopsy and endometrial PCR testing, it was finally diagnosed as vulvar ulcerative cutaneous tuberculosis secondary to genital tuberculosis. Antituberculosis treatment was effective. Cutaneous tuberculosis is called a great imitator. In order to facilitate the diagnosis and treatment of tuberculosis by clinicians, the authors systematically reviewed this disease as well.