Abstract | April 4, 2022
Unicentric Castleman Disease Associated with Covid-19 Pneumonia
- Discuss a potential mechanism for the development of Unicentric Castleman Disease in the context of a Covid-19 infection.
Introduction: Unicentric Castleman Disease (UCD) is a rare lymphoproliferative disorder with a poorly understood mechanism. However, Interleukin-6 (IL-6) has been shown to be upregulated in many cases. Covid-19 has demonstrated significant and sometimes fatal inflammation largely due to IL-6. It is possible that elevated IL-6 levels could create a lymphoproliferative environment amenable to UCD development. We report the first documented case of UCD in a patient with Covid-19 pneumonia and propose a possible IL-6 mediated mechanism.
Case Presentation: A 38-year-old female presented to the endocrinologist due to a reported adrenal incidentaloma. This was found on a CT chest 3 months prior while she had Covid-19 pneumonia. The physical exam was normal. The differential included endocrine tumor, rheumatologic process, and hematologic malignancy. A repeat CT showed a solid left retroperitoneal mass measuring 5.2 x 3.0 x 2.8 cm situated between the left kidney and adrenal gland with adjacent prominent periaortic lymph nodes.
A CT-guided biopsy revealed atypical lymphoid proliferation with prominent reactive germinal centers and expanded marginal zone and germinal center central venules suspicious for Castleman lymphadenopathy. There was a mixture of polyclonal B-cells and T-cells with intact overall immune architecture. Immunoglobulin heavy chain rearrangements showed polyclonal amplification products.
Exploratory laparotomy was performed with removal of a malignant appearing 5 cm left retroperitoneal mass. Pathology was consistent with atypical lymphoid proliferation concerning for Castleman’s disease. Second opinion was obtained and revealed increased IgG positive plasma cells suggesting early lymph node involvement by hyaline-vascular Castleman disease.
Final Diagnosis: After core needle and subsequent excisional biopsies, the diagnosis of Unicentric Castleman Disease was confirmed.
Outcome and Follow-Up: After excision of the pathologic lymph node, the patient remains asymptomatic and has returned to her normal life.
References and Resources:
- Fajgenbaum, D. Unicentric castleman disease. In: Freedman, S, Connor R, ed. UpToDate. Waltham, Mass. 2021.: UpToDate, 2021. https://www.uptodate.com/contents/unicentric-castlemandisease?search=castleman%20disease&source=search_result&selectedTitle=1~65&usage_type=default &display_rank=1. Accessed October 2, 2021.
- Rubin, Eric J., et al. “Interleukin-6 Receptor Inhibition in Covid-19 -Cooling the Inflammatory Soup.” New England Journal of Medicine, vol. 384, no. 16, 2021, pp. 1564–1565., https://doi.org/10.1056/nejme2103108.