Castleman disease with peripheral polyneuropathy: a case report

Abstract

Case Presentation: A 35-year-old female patient was referred to the neurology outpatient department for evaluation of peripheral polyneuropathy in May 2024 and was immediately admitted to the intensive care unit due to sepsis. Three years prior to her referral, she developed sudden, symmetrical, distal paraparesis in her legs, followed by paresthesia. Electroneuromyography performed in 2022 showed severe sensory-motor polyneuropathy with axonal and demyelinating components in the lower limbs. From February to October 2023, the patient was treated at another health-care institution with 7 cycles of methylpredinisolone 1g for 5 days, interspersed with physiotherapy sessions, achieving partial improvement in the deficits. A few months later, there was an insidious and progressive sensory-motor worsening, also affecting the upper limbs. Electroneuromyography had the same pattern as the previous one in January 2024. The patient presented with consumptive syndrome, cutaneous hyperpigmentation, hypothyroidism, thrombocytosis, hepatosplenomegaly, ascites and non-specific vertebral intraosseous lesions. Hematological investigation revealed several lymph nodes with suspicious characteristics in both axillary regions, as well as aberrant plasma cells, but did not detect a monoclonal peak. Screening was negative for autoimmune, metabolic and infectious causes, including HIV in the blood and cerebrospinal fluid. Human herpes virus 8 was not tested due to limitation of available resources. In May 2024 the patient presented with a gradual, bilateral reduction in visual acuity combined with recurrent intracranial hypertension, despite several lumbar punctures. Due to worsening multisystemic involvement, with panserositis refractory to clinical treatment and a new septic condition, the patient did not have perfomance status for surgical approach or chemotherapy treatment and died days after the result of a cervical lymph node biopsy confirming Castleman's disease with a hyaline-vascular pattern. Discussion: Castleman's disease is a rare lymphoproliferative disorder with four subtypes, therefore, has a variable clinical presentation and prognosis. Around 4,300-5,200 new cases are reported in the United States, of which 2,000 are multicentric (associated or not with human herpes virus). It is also included on the criteria for POEMS Syndrome, making diagnosis even harder due to the similarities of this illness and the multicentric Castleman disease subtype. Final Comments: This case reinforces the diagnostic challenges associated with Castleman disease, particularly when presenting with progressive peripheral polyneuropathy and multisystem involvement. It also highlights the importance of early diagnosis in diseases with heterogeneous clinical presentations.