Cellulitis caused by Aeromonas bites that lead to an allergic reaction
Case report published in Case Reports in Infectious Diseases (2022)
Abstract
The allergic reaction due to leech bites is frequently reported due to complications of leech therapy and also unwanted leech infestation. Regularly, the urticarial papules are common, and itching lasts less than 24 h. In the case of leech biting, dermal infection could be caused by leech gut bacterial flora such as Aeromonas spp and histamine from leech saliva. In this case report, a 30-year-old diabetic woman, who works in the field of leech breeding, was bitten by Hirudo orientalis during breeding. Her clinical signs were inflammation, swelling, pain, and redness in the back of her left hand. A microbiological examination revealed that the isolated leech was infected with Aeromona hydrophila. The risk of death due to anaphylactic shock and sepsis is high in some cases of underlying diabetes and immunocompromised individuals. The study pointed out the hazards of leech bites and proposed preventative measures such as using gloves and boots for farm workers.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Case of cellulitis from Aeromonas leech-bite infection complicated by allergic reaction, requiring combined antibiotics and antihistamines.
Why This Matters for Hirudotherapy
This case report describes a 30-year-old diabetic woman working in leech breeding who was bitten by Hirudo orientalis and developed inflammation, swelling, pain, and redness of the hand, with Aeromonas hydrophila isolated from the leech; the authors note that leech-bite reactions range from short-lived urticarial papules to dermal infection from gut flora such as Aeromonas and histamine from leech saliva, and warn that anaphylaxis and sepsis risk is elevated in diabetic or immunocompromised individuals. This is directly relevant to hirudotherapy safety: Aeromonas is the well-recognized leech-gut commensal behind post-leeching infection, reinforcing why infection surveillance, antibiotic prophylaxis considerations, and protective measures matter, especially in higher-risk patients. The caveat is that this is a single case report in an occupational (breeding) bite context rather than controlled therapeutic application, so it illustrates a hazard and preventive lessons (gloves, boots) rather than quantifying infection risk in clinical leech therapy.
Citation
Cellulitis caused by Aeromonas bites that lead to an allergic reaction.
Najjari M et al. · Case reports in infectious diseases, 2022
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