Time to Reconsidering the Potential Role of Leech Salivary Proteins in Medicine: Type-II Kounis Syndrome Triggered by Leech Bite
Tas S, Yildiz BS, Ersin A, Tas U (2025) · Pakistan Journal of Medical Sciences · n=1
Study Profile
- Design
- single case report of a 58-year-old male presenting with allergic myocardial infarction (Type-II Kounis syndrome) following a leech bite, with subsequent coronary angiography demonstrating 90% stenosis of the circumflex artery and successful stent placement (Department of Cardiology, Manisa Celal Bayar University, and Department of Cardiology, Izmir Demokrasi University, Turkey)
- Sample size (n)
- 1
- Intervention
- Description of acute Type-II Kounis syndrome (allergic myocardial infarction) presentation following a leech bite in a patient without prior allergic history; emergency management included cardiopulmonary resuscitation for 10 minutes, intravenous antihistamine, prednisolone, and adrenaline; intensive care monitoring; coronary angiography with stent implantation
- Comparator
- Not applicable - single-patient case report
- Primary endpoint
- Documentation of Kounis syndrome as a serious adverse event of leech bite exposure; identification of leech salivary proteins as a potential trigger of acute coronary syndrome via type I-II hypersensitivity mechanisms
- Primary result
- Successful resuscitation and revascularization with circumflex coronary artery stenting; patient stabilized; case demonstrates that leech bite can trigger Kounis syndrome with simultaneous anaphylaxis and acute coronary syndrome even in patients without prior allergy history; report calls for increased clinical awareness of this rare but potentially lethal complication
- Follow-up duration
- duration of inpatient stay plus post-discharge cardiology follow-up
- PMID
- 39867760
Key Findings
- First reported case in the cardiology literature of Type-II Kounis syndrome triggered by leech bite
- Demonstrates simultaneous allergic and ischemic pathways from leech salivary protein exposure
- Patient required 10 minutes of CPR and emergency cardiology intervention with stent placement
- Strongly reinforces the ASH not-for-home-use guidance and need for clinician supervision
- Calls for clinical awareness of Kounis syndrome in the differential for chest pain after leech exposure
Limitations
- Single case (n=1) - cannot establish incidence or risk factors
- Pre-existing coronary artery disease in the patient is a confounder
- Causation of acute coronary syndrome by leech allergic reaction inferred but not proven mechanistically
- No molecular allergen characterization reported
- Setting (environmental leech exposure, not medical therapy) — relevance to K040187 medical therapy is contextual
Clinical Implications
Tas 2025 documents the first cardiology-literature case of Type-II Kounis syndrome triggered by leech bite, demonstrating that leech salivary proteins can simultaneously trigger anaphylaxis and acute coronary syndrome. For US clinicians administering K040187-cleared medical leech therapy, the trial reinforces the necessity of pre-therapy allergy screening, cardiac risk assessment in elderly or coronary-disease patients, and readiness to manage anaphylaxis with concurrent acute coronary syndrome. The trial complements Wanandy 2024 (leech anaphylaxis with Hymenoptera cross-reactivity) and the broader allergy literature in framing the rare but serious cardiovascular allergic complications of leech exposure.