Scorpion Envenomation Workup
- Author: David Cheng, MD; Chief Editor: Joe Alcock, MD, MS more...
Scorpion envenomation cases vary from those requiring no laboratory tests to scenarios requiring extensive hematologic, electrolyte, and respiratory analysis.
Obtain a CBC count, as Hemiscorpius lepturus has been shown to cause severe hemolysis. In addition, marked leukocytosis suggests induction of a venom-mediated systemic inflammatory response‒like syndrome.
Electrolyte evaluation is warranted in patients with venom-induced salivation, vomiting, and diarrhea.
Coagulation parameters should be measured for venom-induced defibrination because, at high concentrations, the venom is an anticoagulant. Defibrination syndrome has been reported following Mesobuthus tamulus stings.
Glucose levels should be measured to evaluate for hyperglycemia from liver and pancreas dysfunction.
Troponin and NT-proBNP elevation suggests myocarditis.
Creatine kinase and urinalysis help evaluate for venom-induced excessive motor rhabdomyolysis. Renal failure may occur secondary to hemoglobinuria from hemolysis (after H lepturus sting) or myoglobinuria from rhabdomyolysis
Obtain amylase/lipase values to assess for pancreatitis, which is common, from Tityus trinitatis stings.
Patients may have increased aspartate aminotransferase and alanine aminotransferase levels from venom-induced liver cell destruction.
Increased catecholamine, aldosterone, renin angiotensin, and antidiuretic hormone levels are detected a few hours after the sting. The increased levels persist for 6 hours, after which a gradual decline occurs.
Interleukin (IL)–1 levels are elevated in all envenomations.
High levels of IL-6, interferon-gamma, and granulocyte-macrophage colony-stimulating factor are present in severe envenomations.
Radiolabeled antibodies or immunoenzymatic assays help quantify the serum venom level because an association exists between the clinical signs of envenomation and this level.
Obtain arterial blood gas (ABG) measurements as indicated for respiratory distress or to determine acid/base status.
Obtain a chest radiograph in cases of respiratory difficulty. Unilateral pulmonary edema may be seen on chest x-ray films because of the venom effect on pulmonary vascular permeability.
Echocardiography is more sensitive than electrocardiography and creatine kinase assays for assessing myocardial compromise after a scorpion sting. Findings show a diffuse global biventricular hypokinesis with a decreased left and right ventricular ejection fraction of approximately 0.14-0.38. This dysfunction can appear just a few hours after the sting and usually normalizes within 4-8 days. Serial echocardiography findings show that the return of left ventricular function to a normal state correlates to clinical cardiorespiratory improvement.
Color-flow Doppler study findings show mitral incompetence, probably secondary to venom-induced dilated cardiomyopathy.
Myocardial perfusion scintigraphy can also be used to investigate the contractility and perfusion of the cardiac tissue.
Arterial blood gas determinations show a decrease in arterial oxygenation tension and an increase in PCO2 within 15 minutes of the envenomation, findings consistent with mild metabolic acidosis.
Pulmonary artery catheterization findings may include the following:
Elevated systemic vascular resistance occurs up to 4 times the normal level, with elevated mean arterial pressure (MAP) of 203 mm Hg.
Left ventricular failure produces a MAP of 57-69 mm Hg.
Biventricular failure produces a MAP of 47 mm Hg.
Low cardiac index occurs with elevated filling pressures.
Perform serial spirometry measurements to help detect impending venom-induced diaphragmatic failure.
Electrocardiography, if indicated, should be performed. ECG changes persist for 10-12 days before normalizing. ECG changes are observed in 63% of children who have been envenomated. Rhythm disturbances are not dose-dependent but are related to the venom composition. Note the following:
First-degree block - 10.2%
Bundle-branch block - 12.8%
Ventricular repolarization abnormalities - 15%
T-wave inversion - 39%
ST changes - 39%
QTc prolongation - 53%
Sinus tachycardia - Most common rhythm
A possible sequence of ECG changes has been noted. This sequence starts with bizarre, broad-notched, biphasic, peaked T waves with a beat-to-beat variation. This bizarre T wave is followed by the appearance of tiny Q waves and then atrioventricular dissociation with an accelerated junctional rhythm.
Cerebrospinal fluid pleocytosis is evident on spinal tap studies.
The local sting site shows mixed inflammatory cell infiltrates with eosinophils scattered among collagen bundles in an edematous dermis. Myocardial changes, which are most prominent at the papillary muscle and subendocardial region, include focal myocardial necrosis; myofibril destruction, especially at the I band; fine fatty deposits in the cardiac muscle fibers; interstitial edema; and increased cellularity, mainly lymphocytes and monocytes. Changes resemble interstitial hypoxia-induced myocarditis caused by large doses of catecholamines.
Khatony A, Abdi A, Fatahpour T, Towhidi F. The epidemiology of scorpion stings in tropical areas of Kermanshah province, Iran, during 2008 and 2009. J Venom Anim Toxins Incl Trop Dis. 2015. 21:45. [Medline].
Queiroz AM, Sampaio VS, Mendonça I, Fé NF, Sachett J, Ferreira LC, et al. Severity of Scorpion Stings in the Western Brazilian Amazon: A Case-Control Study. PLoS One. 2015. 10 (6):e0128819. [Medline].
Chippaux JP, Goyffon M. Epidemiology of scorpionism: a global appraisal. Acta Trop. 2008 Aug. 107 (2):71-9. [Medline].
van der Meijden A, Coelho P, Rasko M. Variability in venom volume, flow rate and duration in defensive stings of five scorpion species. Toxicon. 2015 Jun 15. 100:60-6. [Medline].
Mowry JB, Spyker DA, Brooks DE, McMillan N, Schauben JL. 2014 Annual Report of the American Association of Poison Control Centers' National Poison Data System (NPDS): 32nd Annual Report. Clin Toxicol (Phila). 2015 Dec. 53 (10):962-1147. [Medline].
Jahan S, Mohammed Al Saigul A, Abdul Rahim Hamed S. Scorpion stings in Qassim, Saudi Arabia--a 5-year surveillance report. Toxicon. 2007 Aug. 50(2):302-5. [Medline].
Shahbazzadeh D, Amirkhani A, Djadid ND, Bigdeli S, Akbari A, Ahari H. Epidemiological and clinical survey of scorpionism in Khuzestan province, Iran. Toxicon. 2009 Mar 15. 53(4):454-9. [Medline].
Dehghankhalili M, Mobaraki H, Akbarzadeh A, Yazdani R, Nazemi A, Ghaffarpasand F, et al. Clinical and Laboratory Characteristics of Pediatric Scorpion Stings: A Report From Southern Iran. Pediatr Emerg Care. 2015 Nov 2. [Medline].
Bosnak M, Ece A, Yolbas I, Bosnak V, Kaplan M, Gurkan F. Scorpion sting envenomation in children in southeast Turkey. Wilderness Environ Med. 2009 Summer. 20(2):118-24. [Medline].
Ulug M, Yaman Y, Yapici F, Can-Ulug N. Scorpion envenomation in children: an analysis of 99 cases. Turk J Pediatr. 2012 Mar-Apr. 54(2):119-27. [Medline].
Langley RL, Morrow WE. Deaths resulting from animal attacks in the United States. Wilderness Environ Med. 1997 Feb. 8(1):8-16. [Medline].
Boyer L, Heubner K, McNally J, Buchanan P. Death from Centruroides scorpion sting allergy [abstract]. J Toxicol Clin Toxicol. 2001. 39:561-562.
Bawaskar HS, Bawaskar PH. Scorpion sting: update. J Assoc Physicians India. 2012 Jan. 60:46-55. [Medline].
Skolnik AB, Ewald MB. Pediatric scorpion envenomation in the United States: morbidity, mortality, and therapeutic innovations. Pediatr Emerg Care. 2013 Jan. 29(1):98-103; quiz 104-5. [Medline].
Bouaziz M, Bahloul M, Kallel H, Samet M, Ksibi H, Dammak H, et al. Epidemiological, clinical characteristics and outcome of severe scorpion envenomation in South Tunisia: multivariate analysis of 951 cases. Toxicon. 2008 Dec 15. 52(8):918-26. [Medline].
Prasad R, Mishra OP, Pandey N, Singh TB. Scorpion sting envenomation in children: factors affecting the outcome. Indian J Pediatr. 2011 May. 78(5):544-8. [Medline].
Guerra CM, Carvalho LF, Colosimo EA, Freire HB. Analysis of variables related to fatal outcomes of scorpion envenomation in children and adolescents in the state of Minas Gerais, Brazil, from 2001 to 2005. J Pediatr (Rio J). 2008 Nov-Dec. 84(6):509-15. [Medline].
Parma JA, Palladino CM. [Scorpion envenomation in Argentina]. Arch Argent Pediatr. 2010 Apr. 108(2):161-7. [Medline].
Freire-Maia L, Pinto GI, Franco I. Mechanism of the cardiovascular effects produced by purified scorpion toxin in the rat. J Pharmacol Exp Ther. 1974 Jan. 188(1):207-13. [Medline].
Pinto MC, Borboleta LR, Melo MB, Labarrére CR, Melo MM. Tityus fasciolatus envenomation induced cardio-respiratory alterations in rats. Toxicon. 2010 Jun 1. 55(6):1132-7. [Medline].
Bahloul M, Chaari A, Dammak H, Samet M, Chtara K, Chelly H, et al. Pulmonary edema following scorpion envenomation: mechanisms, clinical manifestations, diagnosis and treatment. Int J Cardiol. 2013 Jan 10. 162(2):86-91. [Medline].
Bawaskar HS. Diagnostic cardiac premonitory signs and symptoms of red scorpion sting. Lancet. 1982 Mar 6. 1(8271):552-4. [Medline].
Kaplanoglu M, Helvaci MR. Scorpion stings in pregnant women: an analysis of 11 cases and review of literature. Clin Exp Obstet Gynecol. 2015. 42 (2):228-30. [Medline].
Figueiredo AB, Cupo P, Pintya AO, Caligaris F, Marin-Neto JA, Hering SE. [Assessment of myocardial perfusion and function in victims of scorpion envenomation using gated-SPECT]. Arq Bras Cardiol. 2010 Apr. 94(4):444-51. [Medline].
Nouira S, Boukef R, Nciri N, Haguiga H, Elatrous S, Besbes L, et al. A clinical score predicting the need for hospitalization in scorpion envenomation. Am J Emerg Med. 2007 May. 25 (4):414-9. [Medline].
Aksel G, Güler S, Doğan NÖ, Çorbacioğlu ŞK. A randomized trial comparing intravenous paracetamol, topical lidocaine, and ice application for treatment of pain associated with scorpion stings. Hum Exp Toxicol. 2015 Jun. 34 (6):662-7. [Medline].
Chippaux JP. Emerging options for the management of scorpion stings. Drug Des Devel Ther. 2012. 6:165-73. [Medline].
Natu VS, Kamerkar SB, Geeta K, Vidya K, Natu V, Sane S, et al. Efficacy of anti-scorpion venom serum over prazosin in the management of severe scorpion envenomation. J Postgrad Med. 2010 Oct-Dec. 56(4):275-80. [Medline].
Bawaskar HS, Bawaskar PH. Efficacy and safety of scorpion antivenom plus prazosin compared with prazosin alone for venomous scorpion (Mesobuthus tamulus) sting: randomised open label clinical trial. BMJ. 2011 Jan 5. 342:c7136. [Medline]. [Full Text].
Kumar CM, Prasad SV. Echocardiologic evaluation and follow-up of cardiovascular complications in children with scorpion sting in coastal South India. Indian J Crit Care Med. 2015 Jan. 19 (1):42-6. [Medline].
Kumar PM, Krishnamurthy S, Srinivasaraghavan R, Mahadevan S, Harichandrakumar KT. Predictors of Myocardial Dysfunction in Children with Indian Red Scorpion (Mesobuthus tamulus) Sting Envenomation. Indian Pediatr. 2015 Apr. 52 (4):297-301. [Medline].
Tan HH, Mong R. Scorpion stings presenting to an emergency department in Singapore with special reference to Isometrus maculatus. Wilderness Environ Med. 2013 Mar. 24(1):42-7. [Medline].
Abroug F, Souheil E, Ouanes I, Dachraoui F, Fekih-Hassen M, Ouanes Besbes L. Scorpion-related cardiomyopathy: Clinical characteristics, pathophysiology, and treatment. Clin Toxicol (Phila). 2015 Jul. 53 (6):511-8. [Medline].
Sundararaman T, Olithselvan M, Sethuraman KR, Narayan KA. Scorpion envenomation as a risk factor for development of dilated cardiomyopathy. J Assoc Physicians India. 1999 Nov. 47(11):1047-50. [Medline].
Bhoite RR, Bhoite GR, Bagdure DN, Bawaskar HS. Anaphylaxis to scorpion antivenin and its management following envenomation by Indian red scorpion, Mesobuthus tamulus. Indian J Crit Care Med. 2015 Sep. 19 (9):547-9. [Medline].
Gupta BD, Parakh M, Purohit A. Management of scorpion sting: prazosin or dobutamine. J Trop Pediatr. 2010 Apr. 56(2):115-8. [Medline].
Patil SN. A retrospective analysis of a rural set up experience with special reference to dobutamine in prazosin-resistant scorpion sting cases. J Assoc Physicians India. 2009 Apr. 57:301-4. [Medline].
Centruroides (Scorpion) Immune F(ab’)2 (Equine). Prescribing information. Accessed August 9, 2011. [Full Text].