- D3.548 - Refractory and persistent pruritus in an atopic patient: A red flag for underlying malignancy?

Background: Chronic pruritus is a common reason for referral to Allergy clinics and is frequently attributed to atopic or dermatological conditions. However, persistent generalised pruritus without clear cutaneous findings may represent the first manifestation of systemic disease, including malignancy.

Case Presentation: A 36-year-old man with a history of intermittent mild allergic rhinoconjunctivitis (grass, olive and plane tree pollen) and dermographism was referred for evaluation of chronic intractable pruritus and mild eosinophilia. Since January 2024, he reported daily generalised pruritus, involving scalp and palmoplantar areas, severe enough to disturb sleep. Only excoriations were observed; no primary inflammatory skin lesions were identified, apart from a transient self-limited salmon-coloured macular rash months earlier.

He denied fever, respiratory or gastrointestinal symptoms, arthralgia or night sweats, but reported unintentional weight loss of 7–8 kg over 12 months.

Laboratory tests showed eosinophilia (peak 1,200/µL), polyclonal hypergammaglobulinaemia (elevated IgG, IgM and markedly raised IgE), and later elevated LDH (451 U/L) and CRP (13.6 mg/L). Autoimmune screening (ANA, ENA, ANCA), complement levels and parasitological studies were negative.

Chest X-ray revealed mediastinal widening. Thoracic CT demonstrated bulky anterior mediastinal lymphadenopathy (85 × 55 × 135 mm). Biopsy confirmed classical Hodgkin lymphoma, nodular sclerosis subtype. PET-CT showed supradiaphragmatic hypermetabolic adenopathy consistent with stage IIB bulky disease. Treatment consisted of 17 cycles of chemotherapy: initially with ABVD (Adriamycin, Bleomycin, Vinblastine, Dacarbazine), followed by AVD (without Bleomycin), achieving complete metabolic response. Pruritus resolved completely, and inflammatory markers normalized.

Conclusions: This case highlights that pruritus may precede the diagnosis of Hodgkin lymphoma by many months and may initially be misattributed to atopy. The absence of primary skin lesions, presence of eosinophilia and polyclonal hypergammaglobulinaemia as immunological clues, and unexplained weight loss should prompt investigation beyond allergic causes. In Allergy practice, chronic generalised pruritus that is sleep-disturbing, persistent, and biologically unexplained must raise suspicion of systemic autoimmune or malignant disease. Early recognition of these red flags may significantly reduce diagnostic delay and improve outcomes.