Insect bite-like reaction in patients with hematologic malignant neoplasms

Area of Science:

• Dermatology
• Hematology
• Oncology

Background:

• Exaggerated reactions to insect bites are rarely reported in patients with chronic lymphocytic leukemia (CLL).
• Skin lesions typically manifest months to years post-leukemia diagnosis, independent of disease status or treatment.
• This phenomenon is also observed in other hematologic malignancies.

Purpose of the Study:

• To describe the clinical presentation and characteristics of insect bite-like reactions in patients with hematologic disorders.
• To investigate the potential association between these reactions and the underlying hematologic malignancy.
• To explore the diagnostic and prognostic implications of this phenomenon.

Main Methods:

• Case series describing 8 patients with various hematologic disorders experiencing insect bite-like reactions.
• Clinical and histological evaluation of skin lesions.
• Review of patient history, disease course, and treatment response.
• Polymerase chain reaction (PCR) used in one case to detect leukemic cells.

Main Results:

• Patients presented with lesions clinically and histologically resembling insect bites, but without a history of actual insect assault.
• In two cases, the rash preceded the diagnosis of a hematologic malignancy.
• Lesions were persistent, lasting months to years, and resistant to most treatments except systemic corticosteroids.
• Three patients with CLL showed a poorer prognosis than anticipated; leukemic cells were found in the infiltrate of one patient via PCR.

Conclusions:

• Insect bite-like reactions are uncommon, troublesome, and difficult to treat in patients with hematologic malignancies.
• The reaction can occur before the hematologic disorder is diagnosed, necessitating careful evaluation.
• Immunodeficiency is a potential factor in pathogenesis, but further research is needed to clarify the exact mechanisms and prognostic significance.