Case reports

Australia
Pseudechis australis (Mulga snake)
Balmain and McClelland 1982: 1 Pseudechis sp. bite; identification: most probably P. australis (ELISA).
Rowlands et al. 1969: 1 P. australis bite; identification: morphological.
Vines 1978: 1 P. australis bite; identification: morphological.
White 1987b: 2 Pseudechis sp. bite; identification: ELISA and ?morphological.
White 1992: 14 P. australis bites; identification: positive. Systemic envenoming 11/14, 4 cases were severe.

Pseudechis colletti
White 1992:  1 P. colletti bite; identification: positive.

Pseudechis guttatus (Blue-bellied black snake, Spotted black snake)
Sutherland 1983
White 1992: 1 P. guttatus bite; identification: positive.

Pseudechis porphyriacus (Red-bellied black snake)
Sutherland 1983: 5 bites that were attributed to P. porphyriacus; identification: no information on criteria.
White 1992: 15 P. porphyriacus bites; identification: positive 13/15. Systemic envenoming 9/15, no cases were severe.

Papua New Guinea
Pseudechis papuanus
Campbell 1967: 13 bites that were attributed to P. papuanus; identification: morphological (2/13 according to information in Campbell 1967 and pers. comm. 1992, cited in Lalloo et al. 1994).
Lalloo et al. 1994: 9 bites; identification: ELISA. Clinical signs of envenoming 7/9.

Signs & symptoms

Autopharmacological effects

Pseudechis australis
Signs of systemic envenoming 11/14; of these patients, nausea 9/11, vomiting 6/11, abdominal pain 6/11, headache 8/11, collapse shortly after the bite 1/11 (White 1992).

Pseudechis papuanus
Vomiting 2/9, abdominal pain 5/9 (Lalloo et al. 1994).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15; of these patients, nausea 7/9, vomiting 7/9, abdominal pain 7/9, headache 1/9, collapse shortly after the bite 2/9 (White 1992).

Local effects

Pseudechis australis
Signs of systemic envenoming 11/14; of these patients, local pain 11/11, local swelling 8/11, in some cases so extensive that half of the affected extremity was swollen, local erythema or bleeding into the skin 2/11 (White 1992). Local swelling extending to the axilla (Rowlands et al. 1969). Local swelling extending as far as the chest wall. Necrosis of the area around the bite; the patient had applied a tight tourniquet (Vines 1978).

Pseudechis colletti
Only local effects (White 1992).

Pseudechis guttatus
Only local effects (White 1992).

Pseudechis papuanus
Minimal local pain (bite marks barely visible), painful local lymph nodes 4/9, regional lymph nodes painful on palpation 6/9 (Lalloo et al. 1994).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15; of these patients, local pain 8/9, local swelling 7/9, local erythema or bleeding into the skin 4/9 (White 1992).

Haemostatic effects

Pseudechis australis
See Laboratory and physical investigations.

Pseudechis papuanus
Bleeding from the nose or mouth 2/9, bloody sputum 1/9, nosebleeds 1/9 (Lalloo et al. 1994).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15, of these 0/9 had signs of a haemostatic defect (White 1992).

Neurological effects

Pseudechis australis
Signs of systemic envenoming 11/14, of these 0/11 had signs of paralysis (White 1992).

Pseudechis papuanus
Ptosis 5/9, diplopia 1/9, ophthalmoplegia 5/9, dysphagia 3/9, dysarthria 3/9, difficulty in opening the mouth 1/9, slurred speech 4/9, diminished hand grip strength 1/9, respiratory disturbances 1/9 (Lalloo et al. 1994).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15, of these 0/9 had signs of paralysis (White 1992).

Muscular effects

Pseudechis australis
Signs of systemic envenoming 11/14, of these 4/11 had signs of rhabdomyolysis (White 1992).

Marked generalised rhabdomyolysis (autopsy finding) (Rowlands et al. 1969).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15, of these 0/9 had signs of rhabdomyolysis (White 1992).

Cardiac effects

Pseudechis australis
Myocardial necrosis (autopsy finding) (Rowlands et al. 1969).

Renal effects

Pseudechis australis
Signs of systemic envenoming 11/14, of these 0/11 had signs of renal impairment (White 1992).

Pseudechis porphyriacus
Signs of systemic envenoming 9/15, of these 0/9 had signs of renal impairment (White 1992).

Morbidity

Pseudechis australis
Possible necrosis (Vines 1978).

Case fatality rate

Pseudechis australis
Fatality with marked systemic rhabdomyolysis and myocardial necrosis (Rowlands et al. 1969).

Laboratory and physical investigations

1. Haemostasis
Type of haemostatic defect
The haemostatic effects of the venom of the Australian Pseudechis sp. are poorly documented. P. australis venom appears to contain anti-coagulative but no pro-coagulative components. Pseudechis porphyriacus venom appears not to cause any coagulation defects in humans.

In contrast, Pseudechis papuanus causes marked haemostatic defects, including spontaneous haemorrhage. The venom has a haemorrhagic effect, and has a mildly pro-coagulative as well as an antithrombocytic and anti-coagulative effect (Kamiguti et al. 1994, Lalloo et al. 1994).

Haemostatic parameters

2. Creatinine phosphokinase
Maximum 13,758 U/l on day 3 (White 1987b).

3. ELISA

See above.

Treatment (symptomatic)

Pseudechis papuanus
Intubation and artificial respiration 1/9 (Lalloo et al. 1994).

Treatment (specific)

Antivenoms
Pseudechis australis
Black snake antivenom, CSL, Parkville, Australia (Sutherland 1983).

Pseudechis papuanus
Polyvalent antivenom (Australia-New Guinea, Commonwealth Serum Laboratories, Melbourne, Australia) 5/7. In comparison to cases of taipan envenoming, the neurotoxic symptoms appeared to be less marked and to respond better to antivenom treatment (Lalloo et al. 1994). Although P. papuanus venom is no longer used for the production of CSL antivenom (Theakston and Warrell 1991), the CSL polyvalent antivenom (Australia-Papua New Guinea) nonetheless appears to be effective in animal experiments (Kamiguti et al. 1994).

Pseudechis porphyriacus
Tiger snake antivenom, CSL, Parkville, Australia (Sutherland 1983).