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Scorpion envenomation
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Scorpion envenomationAntonio Soutoacasouto@bol.com.brMédico coordenadorUnidade de Medicina Intensiva PediátricaUnidade de Medicina Intensiva Neonatal Hospital Padre Albino
Professor de Pediatria nível II Faculdades Integradas Padre AlbinoCatanduva / SP
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Important public health hazard in tropical andsub-tropical regions
The annual number of scorpion stings cases exceeds 1.23million, of which over 32250 may be fatal
Brazil:
•8.000 /year•3 /100.000 habitants•50% Minas Gerais e São Paulo
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
•60s and 70s, cases fatality rate of up to 30%
•Since the advent of vasodilators prazosin, captopril, nifedipine, sodium nitroprusside, hydrazine, scorpionantivenom and intensive care management the fatality is dropped to <2-4%.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
•Tityus serrulatus scorpion venom has shown to bemore deleterious to children than to adults
•This effect is suggested to be body weight dependent. •The children would have higher venom concentration in their body liquids.•More severe systemic symptoms, including higherlethality.
•Buthidae species can result a life threatening systemiceffects
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
T. serrulatus T. bahiensis
T. stigmurus T. obscurusT. metuendus
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Familia Buthidae (Hemiscorpius Lepturus)
Genero•Buthus (Mediterranean Spain to the Middle East)•Parabuthus (western and southern Africa)•Hottentotta (South Africa to south east Asia)•Leiurus (northern Africa and middle East)•Androctonus (northern Africa to southeast Asia)•Centruroides (southern united states, Mexico, central America and Caribbean)•Mesobuthus (through out the Asia)
Tityus (central America, south America and the Caribbean)
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
•Arthropods in the class Arachnid•Viviparous and cannibalistic
Scorpion have been able to survive in heat, drought, freezing conditions for weeks, desert condition andstarvation for months and total immersion of water for days.
Survival independent of ecologicalcondition
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Scorpion Venom
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Scorpion Venom
Cocktail•Low molecular weight basic proteins, neurotoxins, nucleotides, aminoacids, oligopeptides, cardipotoxins, nephrotoxin, hemolytic toxins, phosphodiesterase, phospholipase A, hyaluroinidase.
•Acetylcholineesterase, glycosaminoglycans, histamine, serotonin. 5-hydroxyptamine and proteins that inhibitprotease, angiotensinase and succinate –dehydrogenese, ribonuclease, 5- nucleotidase.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Scorpion Venom
The lethality varies with species
•Venom almost complete absorption would occur in 7-8 hours•70% of maximum concentration in the blood within 15 minutes•Half life of intravenously injected venom is between 4 to 7 minutes•Takes 4.2 to 13.4 hours for elimination from blood.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Regulating venom ejections
This ability explains the variation ofintensity of symptoms and existence of
“dry” sting without envenoming.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Scorpion Venom
Neurotoxins
Highly lethal than neurotoxin of snake venom.The LD50 of some neurotoxins 10 fold more potent thancyanide
Act mainly on excitable cells of nerves and musclesIntense and persistent depolarization of autonomic nerveswith massive release of autonomic neuromuscular neurotransmitter.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
“autonomic storm”
Clinical laboratory data reportingincreased catecholamine metabolite excretion
and elevated plasma renin and aldosteroneare consistent with the stimulatory effects
of the venom on the autonomic nervous system.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Clinical effects•depends upon the species of scorpion•dose of venom injected
Severity•Age•Time between sting and hospitalization•Children with 3.9-10% fatality irrespective of intensive care management from Israel, Turkey and India
Clinically “autonomic storm”releasing massive amounts of catecholamines
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Transient parasympathetic stimulation
vomiting, profuse sweating, ropy salivation, bradycardia, ventricular pre mature contraction, priapism in male, hypotension
Prolonged sympathetic stimulation
cold extremities, hypertension, tachycardia, pulmonary edema and shock
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Clinical manifestations/ severity 4 grades
Grade 1: severe excruciating local pain radiating along with corresponding dermatomes, mild local oedema, without systemic involvement.
Grade 2: signs and symptoms of autonomic storm characterized by acetyl choline excess or parasympathetic stimulation and sympathetic stimulation
Grade 3: cold extremities, tachycardia, hypotension or hypertension withpulmonary edema (Respiratory rate > 24 per minute, basal rales or crackles in lungs).
Grade 4: tachycardia, hypotension with or without pulmonaryedema with warm extremities (warm shock).
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Sixteen scientists (Algeria, Argentina, Bolivia, Egypt,
India, Israel, Mexico, Morocco, Saudi Arabia, Tunis ia and Turkey).
2009 consensus was reached
Class I : Local manifestations
Class II : Systemic involvement
Class III : Cardiogenic failure, hypotension, ventri culararrhythmia, bradycardia, cardiovascular collapse, Respiratory failure- cyanosis, dyspnoea, pulmonary edema, neurological failure
Glasgow score < 6 (in absence of sedation), paralysis.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Local Manifestations
•Soon after sting •Severe radiating pain
•Inconsolable, incessant crying in a child due to pain there is transient tachycardia, rise in blood pressure, mild sweating but extremities are warm.
Severe pain without systemic involvement suggestive of benign or dry sting by venomous species.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Systemic Manifestations
Vomiting : due to autonomic storm often is due to serotonic content of venom
Profuse sweating : sweat literally flows all over body Clinically it is called “skin diarrhea”, persist for 3-17 hours.
Salivation : Thick ropy salivation due to stimulationof bronchial mucus glands, contributing factors for respiratory failure, occurs soon after sting and it persists for 2-4 hours.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Priapism : seen in almost all victims of pediatric age
Priapism is diagnostic of venomous envenomingbut its absence or disappearance did not correlate the outcome. It persists for 5-16 hours.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Vomiting, sweating, salivation, priapism a diagnostic cardiac signs and symptoms of
scorpion sting suggestive of free circulating venom in the blood,
can be accessible to antivenin therapy.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Cardiovascular system mostly affected by venomoussting. Clinical manifestations depends upon the durationof envenoming.
Hypertension, cardiac arrhythmias, tachybradycardia, pulmonary edema, hypotension and shock are not the different syndromes but of one process of ongoing autonomic storm.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
The American Journal of Cardiology, 67:7; 655-657
Tityus serrulatus
The cardiovascular manifestations
Arterial hypertension or hypotension, heart failure, pulmonary edema, shock and electrocardiographic changes.
“acute myocardial infarction-likepattern.”
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Tityus serrulatus
The cardiovascular manifestations
Myocardial damage and depressed left ventricular systolic function.
Pulmonary edema attributed to left ventricular failure or to increased pulmonary vascular permeability.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Hypertension :
Hyper-renemia and sympathetic stimulation rapid and significant increase level of epinephrine, norepinephrine, endothelin, atrial nitriuretic peptide.
Accumulation of angiotensin II accelerate the myocardial injury and oxygen demand.
Alpha receptors stimulation.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Hypertension :
45-70% within 30 minutes to 8 hours with Bradycardia
Main complaints are headache, chest discomfort, suffocation and per oral parasthesia.
Children look agitated confused and have propped up eyes, oculogyric phenomenon, puffy face, decreased level of consciousness and convulsions;
If untreated the hypertensive effect is long lasting and result in development of myocardial failure and pulmonary dema
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Tachycardia :
Raised level of circulating catecholamines by toxin on beta adrenergic receptors
5-20% after 6-7 hours supraventricular tachycardia (heart rate 110-240 per minute)
Sudden onset of tachycardia occurs in a recovering hospitalized patient
Impaired left ventricular filling, reduction in cardiac out put due to mark tachycardia particularly in children result in delirium and convulsion due to anoxia to the brain
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Hypotension :
Hypovolemia and cardiac arrhythmias.
Reduction in systemic vascular resistance a hypokineticphase accompanied by raised heart rate, hypotensionwith shock reflecting an alter left ventricular contractility.
Depletion of catecholamines from nerve terminals because of autonomic storm.
Venom inhibits kinase II enzyme and lead to accumulation of bradykinin a neuromuscular agent incriminated for development of pulmonary edema and hypotension
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Pulmonary edema
Develop within 30 minutes with severe hypertension and may develop after 36 hours of sting with hypotension and tachycardia.
Acute onset of tachydyspnoea, tachycardia, summation gallop, systolic murmur, cold extremities, sudden onset of intractable cough, bilateral moist rales and low volume fast thready pulse.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Management
Fluid loss
vomiting, sweating and salivationcorrect the fluid balance
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Management
Scorpion antivenom (SAV) :Without skin test,Administered as early as possible and through venousroute
•SAV is specific treatment of scorpion sting’s therapy•Randomized controlled trials •Antivenom resolved the neurological manifestations within four hours. •SAV reduced the levels of circulating unbound venom.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Management
Prazosin
Alpha receptors stimulation plays an important role in thepathogenesis of scorpion sting.
Phosphodisterase inhibitor, it reduces preload and leftventricular impedance without raising heart rate.
Prazosin is a physiological antidote to scorpion venomactions
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Management
Angiotensin converting enzyme inhibitor captoprilimproves the pulmonary edema and cardiogenic shockdue to scorpion sting.
Victims who presented in hypokinetic phase due to bothventricular dysfunction, clinically characterized byhypotension, shock, tachycardia, delirium with or withoutpulmonary edema and warm extremities,
Dobutamine infusion 5-20 microgram /kg/min.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Management
Nitroglycerine (NTG) drip 0.5 to 5 microgram /kg/min byimproving heart dysfunction and reduction in pulmonarycongestion.
Venodilator action of NTG reduces the preload of theheart and it improves the intrapulmonary shunting andalso relaxes the epicardial coronary arteries and its collaterals.
Amiodarone improves the survival by reduction ofserum nor-epinephrine level in four children with scorpionsting
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
antivenin therapyantivenin therapy
4-5 ampoules (moderate)
8-10 ampoules (severe)
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
•Tityus species of scorpions are endemic to SouthAmerica, particularly Brazil. An F(ab)2 for Tityusserrulatus antivenom is available from Fundação Ezequiel Dias (FUNED), in Belo Horizonte,Brazil.
•T. serrulatus envenomation treated with antivenom, vomiting and local pain decreased within 1 hour, andcardiorespiratory manifestations disappeared within 6 to 24 hours in all patients except the 2/18 who presentedwith acute lung injury. 16/18 patients recoveredcompletely by 24 hours.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Antivenom therapy must be applied as soon as possibleafter envenoming.
Antivenom preparations•higher purity, greater potency and minimal (or absent) side-efects
•widely shared among clinicians in charge of scorpionenvenoming, that antivenom therapy is the most efectivespecific treatment of severe cases.
Its use is still justified on the basis of observations bothempiric clinical and in experimental models.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
�������� KeepKeep in in youryour mindmind : : whenwhen in a in a endemicendemicregionregion , , wewe mustmust allwaysallways thinkthink aboutaboutscorpionscorpion envenomationenvenomation whenwhen wewe havehave a a childchild cryingcrying , , vomitingvomiting , , withwith profuse sweating, salivation andand arterial arterial hypertensionhypertension withoutwithout a cause.a cause.
Dr. Antonio Souto acasouto@terra.com.br 2013
UTI Pediátrica & Neonatal Hospital Padre Albino
Thank you!
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