[Persistent scabietic nodules with cutaneous lymphoplasia]

Area of Science:

• Dermatology
• Immunology
• Pathology

Background:

• Scabious nodules, persistent lesions following scabies infestation, present diagnostic challenges.
• Distinguishing between benign lymphoid hyperplasia and malignant lymphoma in these nodules is crucial.

Observation:

• Two patients with year-long post-scabious nodules exhibited histological lymphoid hyperplasia, initially raising suspicion of lymphoma.
• Literature review identified six cases of pseudolymphomatous scabious nodules, with only one showing lymphoid follicle formation.

Findings:

• Persistent scabious nodules can display "Darier's sign" due to increased mast cells, potentially causing pruritus.
• Histological analysis is key to differentiating cutaneous lymphoplasia from lymphoma.
• Other conditions like lymphadenosis benigna cutis, dermatofibroma, and urticaria pigmentosa should be considered in differential diagnosis.

Implications:

• Cutaneous lymphoplasia in persistent scabious nodules suggests a significant role for immunological factors in scabies.
• Accurate diagnosis is essential for appropriate patient management and treatment.
• Further research into the immunological mechanisms underlying scabies complications is warranted.