The pathogenesis of granulomatous rosacea (GR), the only variant of rosacea, is unclear. To investigate the differences between GR and non-granulomatous rosacea (NGR) in clinical characteristics, histopathological changes and gene expression for the purpose of providing new ideas on the pathogenesis of rosacea. A total of 30 GR and 60 NGR patients were included. Their clinical and histopathological information was collected retrospectively, and the characteristics of immune cell infiltration were investigated by multiple immunohistochemical staining. RNA sequencing and transcriptome analysis were performed on three pairs of skin samples from GR and NGR patients, respectively. Then, the expressions of candidate genes that were potentially associated with granuloma formation were verified by immunohistochemical staining. It was found that GR patients were more prone to the occurrence of rosacea in the forehead, periocular and perioral skin (p = 0.001, p < 0.001, p = 0.001), and presented more severe papules and pustules when compared with NGR patients (p = 0.032). For histopathological features, the inflammatory cells primarily infiltrated around hair follicles in the GR group and around blood vessels in the NGR group. In addition, the neutrophils were richer (p = 0.036) and the expression levels of CD4+ , CD8+ and CD68+ cells were higher (p = 0.047, p < 0.001, p < 0.001) in the GR group than in the NGR group. In addition, the GR group had apparent collagen hyperplasia (p = 0.026). A total of 420 differentially expressed genes (DEGs) were detected, and bioinformatics analysis showed that the DEGs were enriched in neutrophil activation, adaptive immune response and other biological processes. Lastly, the candidate genes related to neutrophil activation and collagen hyperplasia, i.e., Cathepsin S (CTSS), Cathepsin Z (CTSZ) and matrix metalloproteinases 9 (MMP9), were confirmed to be highly expressed in the GR group. The clinical and histopathological features of GR exhibited a very diverse pattern compared with NGR, and the underlying mechanisms may be related to neutrophil activation and collagen hyperplasia.

Here, we report a case of rubella virus-induced granulomatous dermatitis in a young girl with immunodeficiency caused by DCLRE1C gene mutations. The patient was a 6-year-old girl who presented with multiple erythematous plaques on the face and limbs. Biopsies of the lesions revealed tuberculoid necrotizing granulomas. No pathogens could be identified on extensive special stains, tissue cultures, or PCR-based microbiology assays. Metagenomic next-generation sequencing analysis revealed the rubella virus. Underlying atypical severe combined immunodeficiency was recognized based on the patient\'s history of repetitive infections since birth, low T-cell, B-cell, and NK cell counts, and abnormal immunoglobulins and complements. Whole-exome sequencing revealed the genetic abnormality of the atypical severe combined immunodeficiency (SCID), and compound heterozygous mutations of the DCLRE1C gene were detected. This report highlights the diagnostic values of metagenomic next-generation sequencing in identifying rare pathogens causing cutaneous granulomas in patients with atypical SCID.

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare chronic inflammatory disorder of unknown etiology that most commonly presents as painless lymphadenopathy or subcutaneous masses in the head and neck region. The pathogenesis of the disease is not yet clear. The differential diagnosis is determined using characteristic histological features, such as significant vascular proliferation, lymphocytes and eosinophil inflammation in the dermis. Here is presented the case of a patient with a solitary nodule of ALHE masquerading as pyogenic granuloma (PG). A 47 year-old male patient was admitted with an isolated lump on the right side of the back, which had been present for ~6 months; the nodule appeared to have characteristics of PG and was ~1.8×1.0 cm2 in diameter. To the best of our knowledge, this is the first case report regarding ALHE arising in the back. The present report discusses the manifestation, histopathological features and treatment of the case.

OBJECTIVE: We report the case of a 59-year-old male patient who presented with space-occupying lesions in the pancreas and liver suggestive of metastatic pancreatic cancer.
METHODS: Whole-body F-18 fluorodeoxyglucose (FDG) PET/CT imaging and enhanced CT imaging of the lesions were performed in addition to abdominal ultrasound, ERCP, and MRCP. Tumor markers, including CA199 and AFP, were also evaluated.
RESULTS: PET/CT imaging showed a soft tissue mass with indistinct boundaries in the head of the pancreas with a maximum SUV of 4.39. A less dense shadow was also found in the left lobe of the liver with an indistinct boundary and a maximum SUV of 4.13. Enhanced CT revealed an enhancing mass in the head of the pancreas on arterial phase imaging as well as a mildly enhancing focus in the left lobe of the liver. The patient was diagnosed with a space-occupying lesion of the uncinate process of the pancreas suggestive of pancreatic cancer with metastasis to the liver. However, serum tumor markers were normal. Postoperative pathology was consistent with chronic pancreatitis and old hepatic schistosomiasis associated with granulomatous inflammation of the liver.
CONCLUSIONS: This case of mass-forming pancreatitis and granulomatous inflammation in old hepatic schistosomiasis mimicked metastatic pancreatic cancer on PET/CT. Such false positive lesions have not been reported before, and further exploration and investigation are needed.

Mycosis fungoides (MF) represents the most common type of cutaneous lymphoma. The diagnosis of MF may occasionally be challenging, particularly for variants of MF such as folliculotropic MF, syringotropic MF and granulomatous MF. Herein, we describe a case of MF in which syringotropism and a prominent granulomatous reaction were noted around the affected eccrine gland. This case represents a rare example of MF with multiple unusual histopathological features, including syringotropism, a granulomatous reaction and a reactive B-cell proliferation.