| Summary: | Early diagnosis of snake envenomation is essential, especially neurotoxicity and myotoxicity. We investigated the diagnostic value of serum phospholipase (PLA<sub>2</sub>) in Australian snakebites. In total, 115 envenomated and 80 non-envenomated patients were recruited over 2 years, in which an early blood sample was available pre-antivenom. Serum samples were analyzed for secretory PLA<sub>2</sub> activity using a Cayman sPLA<sub>2</sub> assay kit (#765001 Cayman Chemical Company, Ann Arbor MI, USA). Venom concentrations were measured for snake identification using venom-specific enzyme immunoassay. The most common snakes were <i>Pseudonaja</i> spp. (33), <i>Notechis scutatus</i> (24), <i>Pseudechis porphyriacus</i> (19) and <i>Tropidechis carinatus</i> (17). There was a significant difference in median PLA<sub>2</sub> activity between non-envenomated (9 nmol/min/mL; IQR: 7–11) and envenomated patients (19 nmol/min/mL; IQR: 10–66, <i>p</i> < 0.0001) but <i>Pseudonaja</i> spp. were not different to non-envenomated. There was a significant correlation between venom concentrations and PLA<sub>2</sub> activity (r = 0.71; <i>p</i> < 0.0001). PLA<sub>2</sub> activity was predictive for envenomation; area under the receiver-operating-characteristic curve (AUC-ROC), 0.79 (95% confidence intervals [95%CI]: 0.72–0.85), which improved with brown snakes excluded, AUC-ROC, 0.88 (95%CI: 0.82–0.94). A cut-point of 16 nmol/min/mL gives a sensitivity of 72% and specificity of 100% for Australian snakes, excluding <i>Pseudonaja</i>. PLA<sub>2</sub> activity was a good early predictor of envenomation in most Australian elapid bites. A bedside PLA<sub>2</sub> activity test has potential utility for early case identification but may not be useful for excluding envenomation.
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