Leech-bite induced anaphylaxis with or without Hymenoptera venom sensitization
Wanandy T, Bradley I, Tovar Lopez CD, Cotton BTB, Handley SA, Mulcahy EM, Adriana Le TT, Lau WY (2024) · The Journal of Allergy and Clinical Immunology: In Practice · n=0
Study Profile
- Design
- case series with immunologic characterization of patients presenting with leech-bite-induced anaphylaxis with and without concurrent Hymenoptera (bee/wasp) venom sensitization (Department of Clinical Immunology and Allergy, incorporating the Jack Jumper Allergy Program, Royal Hobart Hospital, Hobart, Tasmania, Australia)
- Sample size (n)
- 0
- Intervention
- Clinical immunologic characterization including serum tryptase, specific IgE measurements, and component-resolved diagnostics in patients presenting with anaphylaxis after leech bite; cross-reactivity with Hymenoptera venom allergens evaluated
- Comparator
- Comparison of leech-bite anaphylaxis patients with and without Hymenoptera venom sensitization (within-cohort allergy phenotype analysis)
- Primary endpoint
- Identification of leech-bite-specific anaphylaxis cases and characterization of cross-reactivity patterns with Hymenoptera venom allergens
- Primary result
- Documented Australian clinical experience of anaphylaxis following leech bites in environmental (non-medical) exposures, with characterization of specific IgE patterns and cross-reactivity with Hymenoptera venom in a subset of patients; abstract emphasizes the need for clinical recognition of leech-bite anaphylaxis as a distinct entity requiring allergy workup
- Follow-up duration
- duration of immunologic workup plus subsequent specialty follow-up (variable)
- PMID
- 39067855
Key Findings
- Australian case series adding to the global literature on leech-bite-induced anaphylaxis
- Documents immunologic cross-reactivity between leech salivary allergens and Hymenoptera venom in a subset of patients
- Highlights need for pre-therapy allergy history screening in patients receiving medical leech therapy
- Reinforces that leech-bite anaphylaxis is a real (though rare) clinical entity requiring specialty allergy workup
- Adds Tasmanian/Australian geographic representation to the leech-allergy safety literature
Limitations
- Small case series — incidence rates cannot be estimated from these data
- Mostly environmental (non-medical-leech) exposures — direct relevance to K040187 medical leech therapy is contextual
- Specific allergens identified by molecular methods only — clinical risk stratification still evolving
- No standardized desensitization protocol described
- Selection bias — dramatic anaphylaxis cases over-represented
Clinical Implications
Wanandy 2024 reinforces that leech-bite-induced anaphylaxis is a recognized clinical entity with documented cross-reactivity to Hymenoptera venom in a subset of patients. For US clinicians administering K040187-cleared medical leech therapy, the trial supports routine pre-therapy allergy history screening (including history of bee/wasp sting reactions), readiness to recognize and manage anaphylaxis, and appropriate consultation with allergy/immunology specialists for high-risk patients. The trial complements the broader leech-allergy literature (Li 2025, Tas 2025 Kounis syndrome) and underpins ASH's standing safety guidance that leech therapy requires clinician supervision and appropriate emergency response capability.