# Vascular insufficiency in the extremities following jellyfish-sting envenomation in Malaysia

## TL;DR

Jellyfish stings in Malaysia can cause delayed blood vessel problems in children, which can be treated with a drug called iloprost to prevent serious complications.

## Contribution

This study is the first to document and analyze delayed arterial vasospasm from jellyfish stings in Malaysia and evaluate iloprost treatment effectiveness.

## Key findings

- Four cases of vascular insufficiency were identified in children aged 7–12 years following jellyfish stings in coastal Penang.
- Intravenous iloprost improved perfusion in all cases with minimal adverse effects and no deaths.
- Three patients fully recovered, while one had residual scarring and contracture.

## Abstract

Vascular insufficiency is an uncommon but potentially limb-threatening complication of jellyfish envenomation, with limited documentation in Southeast Asia. This study characterizes its epidemiology, clinical course, and response to targeted vasodilator therapy in Malaysia.

A retrospective cohort review was conducted for confirmed jellyfish-sting cases complicated by vascular insufficiency reported to the Remote Envenomation Consultancy Services (RECS) from 2017 to 2022. Demographic, geographic, clinical, and management data were extracted from RECS consultation logs. Serial Doppler ultrasound findings and treatment responses were analysed descriptively.

Among 105 jellyfish sting consultations, four (3.8 %) cases of vascular insufficiency were identified, all occurring in coastal Penang and affecting children aged 7–12 years. All primary stings involved the upper limbs; two had concurrent lower limb lesions. The onset of peripheral numbness and cyanosis occurred on day three post-sting. Doppler ultrasonography revealed subcutaneous oedema, reduced arterial calibre, and diminished flow velocities consistent with arterial vasospasm. All patients received intravenous iloprost (0.5–2 ng/kg/min) with gradual tapering, guided by clinical and Doppler parameters. Rapid improvement in perfusion was documented in all cases, with minimal adverse effects (vomiting, dyspnoea, haematuria). Hospitalization lasted 12–32 days. Three patients achieved full functional recovery; one had residual scarring and contracture. No deaths occurred.

Delayed-onset arterial vasospasm can complicate paediatric jellyfish stings, particularly in the upper limb. Early recognition of evolving ischemic signs and timely initiation of iloprost with structured tapering may avert tissue loss. Broader drug availability and standardized treatment algorithms are needed to optimize outcomes in resource-limited coastal settings.

Image 1

•Jellyfish sting envenoming can cause delayed-onset vasospasm in children.•Serial monitoring for pain, discoloration, swelling, and numbness is vital.•Intravenous iloprost effectively reverses limb ischemia from jellyfish envenomation.•Gradual iloprost tapering with Doppler Ultrasonography minimizes rebound vasospasm.

Jellyfish sting envenoming can cause delayed-onset vasospasm in children.

Serial monitoring for pain, discoloration, swelling, and numbness is vital.

Intravenous iloprost effectively reverses limb ischemia from jellyfish envenomation.

Gradual iloprost tapering with Doppler Ultrasonography minimizes rebound vasospasm.