A cross-sectional study of the histopathology and immunology of alopecia areata: Unearthing the role of the Janus kinase–signal transducer and activator of transcription pathway

Background: Alopecia areata is an autoimmune disease that occurs as a result of the loss of the inherent immune privilege of the hair follicle. It has been recently demonstrated that the interferon-γ/interleukin-15 feedback loop that signals via the Janus kinase–signal transducer and activator of transcription pathway is critical to the breakdown of this immune privilege. Aims: To evaluate the immunological distribution of CD4+ T-cells, CD8+ T-cells, phosphorylated signal transducer and activator of transcription 1 and study its relation with the clinical and histopathological findings of the disease. Materials and Methods: A total of 30 patients of alopecia areata were included in the study. Following a detailed history and clinical examination, a scalp biopsy was performed. Histopathology was studied and immunohistochemistry was done to demonstrate the positivity and distribution of CD4+ T-cells, CD8+ T-cells and phosphorylated signal transducer and activator of transcription 1. Results: The follicular count, number of anagen and terminal hair were found to be decreased, whereas the catagen, telogen and vellus hair were found to be increased in number. A peribulbar CD4+ T-cell infiltrate was seen in 70% cases, whereas a CD8+ T-cell infiltrate was seen in 83.3% cases. An intrabulbar CD4+ T-cell infiltrate was seen in 26.7% cases, whereas a CD8+ T-cell infiltrate was seen in 70% cases. Among the 25 hair follicles dermal papilla identified, 36.8% cases were found to be positive for phospho-signal transducer and activation of transcription-1. Limitations: The drawbacks of our study included a small sample size and the use of only vertical sectioning for the scalp biopsy samples. Conclusion: Phosphorylated signal transducer and activator of transcription 1 positivity as an indicator of signalling via the Janus kinase-1/2 pathway was seen in 36.8% of our cases highlighting the integral role of this pathway in the pathogenesis of alopecia areata.

A case of primary rectal non-Hodgkin's lymphoma treated with chemotherapy.

Primary rectal non-Hodgkin's lymphoma is a rare disease. Surgery has been proposed as the primary treatment modality for colorectal lymphomas. We report a case of rectal non-Hodgkin's lymphoma (B cell large cell type, Ann Arbor Stage 1E) who responded completely to systemic chemotherapy.

Bilateral ocular scrofuloderma with orbital tuberculosis.

Ocular scrofuloderma with orbital tuberculosis is a rarely described presentation of childhood tuberculosis. Bilateral involvement has not been reported earlier in the medical literature. Here is reported a 3-year-old boy who presented with bilateral infraorbital swellings of tubercular etiology. Computed tomography (CT) scan of the upper face revealed enhancing soft tissue lesions in both the lower lids of the eyes, with extraconal extension into the orbits and with erosion of the right zygomatic bone. Tubercular etiology was confirmed by the Ziehl Neelsen staining of the aspirate from the lesion, which was positive for acid-fast bacilli and growth of Mycobacterium tuberculosis in the aspirate culture. The patient showed marked improvement of his lesions on anti-tubercular treatment.