Cerebral infarction after envenomation by viper

Cerebral venous sinus thrombosis following Russell's viper (Daboia russelii) envenomation: A case report and review of the literature

Snakebite is a life-threatening and often-neglected public health hazard with high chronic disability and mortality, mainly faced by rural communities in the tropics/subtropics. Stroke and neuromuscular paralysis are the most severe neurological complications. However, cerebral venous sinus thrombosis has rarely been reported among cerebrovascular complications. We report a previously healthy middle-aged Indian female who developed cerebral venous sinus thrombosis preceded by features of disseminated bleeding diathesis following Russell's viper bite. The cerebral venous sinus thrombosis was diagnosed by magnetic resonance imaging. The patient responded well to treatment with antivenom and subcutaneous enoxaparin and had no demonstrable neurological deficits at three months of follow-up.

Massive acute ischemic stroke after Bothrops spp. envenomation in southwestern Colombia: Case report and literature review

Bothrops spp. envenomation and its relationship with ischemic stroke has complex pathogenesis. Local effects such as edema, pain, redness, necrosis, and systemic manifestations like coagulation disorders, thrombosis, renal failure, and hemorrhage have been reported. Hemorrhagic stroke is a common neurological complication but ischemic stroke is poorly understood. We present here the case of a 50-year-old male with no comorbidities referred from a rural area in southwest Colombia with a Bothrops spp. snakebite on the left hand. On admission, the patient presented with a deterioration of consciousness and required mechanical ventilation assistance. The MRI showed multiple ischemic areas in the bilateral frontaltemporal and occipital regions. Two months later, the patient had a favorable resolution, although central paresis in the III and VI cranial nerves and positive Babinski's sign persisted. As already mentioned, the pathophysiology of ischemic stroke due to snakebite is complex but the procoagulant activity of the venom components, the hypovolemic shock, the endothelial damage, and the thromboinflammation can explain it, and although it rarely occurs, it should be considered as a complication of ophidian accidents caused by Bothrops spp.

Potential Role of Platelet-Activating C-Type Lectin-Like Proteins in Viper Envenomation Induced Thrombotic Microangiopathy Symptom

Envenomation by viperid snakes may lead to severe bleeding, consumption coagulopathy, and thrombotic microangiopathy symptoms. The exact etiology or toxins responsible for thrombotic microangiopathy symptoms after snake envenomation remain obscure. Snake C-type lectin-like proteins (snaclecs) are one of the main non-enzymatic protein constituents in viper venoms, of which a majority are considered as modulators of thrombosis and hemostasis. In this study, we demonstrated that two snaclecs (mucetin and stejnulxin), isolated and identified from Protobothrops mucrosquamatus and Trimeresurus stejnegeri venoms, directly induced platelet degranulation and clot-retraction in vitro, and microvascular thrombosis has been confirmed in various organs in vivo. These snaclecs reduced cerebral blood flow and impaired motor balance and spatial memories in mice, which partially represent the thrombotic microangiopathy symptoms in some snakebite patients. The functional blocking of these snaclecs with antibodies alleviated the viper venom induced platelet activation and thrombotic microangiopathy-like symptoms. Understanding the pathophysiology of thrombotic microangiopathy associated with snake envenoming may lead to emerging therapeutic strategies.

Novel Treatment Strategy for Patients with Venom-Induced Consumptive Coagulopathy from a Pit Viper Bite

Pit viper venom commonly causes venom-induced consumptive coagulopathy (VICC), which can be complicated by life-threatening hemorrhage. VICC has a complex pathophysiology affecting multiple steps of the coagulation pathway. Early detection of VICC is challenging because conventional blood tests such as prothrombin time (PT) and activated partial thromboplastin time (aPTT) are unreliable for early-stage monitoring of VICC progress. As the effects on the coagulation cascade may differ, even in the same species, the traditional coagulation pathways cannot fully explain the mechanisms involved in VICC or may be too slow to have any clinical utility. Antivenom should be promptly administered to neutralize the lethal toxins, although its efficacy remains controversial. Transfusion, including fresh frozen plasma, cryoprecipitate, and specific clotting factors, has also been performed in patients with bleeding. The effectiveness of viscoelastic monitoring in the treatment of VICC remains poorly understood. The development of VICC can be clarified using thromboelastography (TEG), which shows the procoagulant and anticoagulant effects of snake venom. Therefore, we believe that TEG may be able to be used to guide hemostatic resuscitation in victims of VICC. Here, we aim to discuss the advantages of TEG by comparing it with traditional coagulation tests and propose potential treatment options for VICC.

Snake C-Type Lectins Potentially Contribute to the Prey Immobilization in Protobothrops mucrosquamatus and Trimeresurus stejnegeri Venoms

Snake venoms contain components selected to immobilize prey. The venoms from Elapidae mainly contain neurotoxins, which are critical for rapid prey paralysis, while the venoms from Viperidae and Colubridae may contain fewer neurotoxins but are likely to induce circulatory disorders. Here, we show that the venoms from Protobothrops mucrosquamatus and Trimeresurus stejnegeri are comparable to those of Naja atra in prey immobilization. Further studies indicate that snake C-type lectin-like proteins (snaclecs), which are one of the main nonenzymatic components in viper venoms, are responsible for rapid prey immobilization. Snaclecs (mucetin and stejnulxin) from the venoms of P. mucrosquamatus and T. stejnegeri induce the aggregation of both mammalian platelets and avian thrombocytes, leading to acute cerebral ischemia, and reduced animal locomotor activity and exploration in the open field test. Viper venoms in the absence of snaclecs fail to aggregate platelets and thrombocytes, and thus show an attenuated ability to cause cerebral ischemia and immobilization of their prey. This work provides novel insights into the prey immobilization mechanism of Viperidae snakes and the understanding of viper envenomation-induced cerebral infarction.

Acute cerebral infarction following a Trimeresurus stejnegeri snakebite: A case report

RATIONALE

Acute cerebral infarction after snake bites is rare. The underlying mechanism causing the thrombotic process remains complex and unknown.

PATIENT CONCERNS

We herein describe a 49-year-old female who was bitten by a Trimeresurus stejnegeri. After 4 days of biting, she developed acute ischemic infarct.

DIAGNOSIS

The patient exhibited right side weakness and speech disturbances. Brain computed tomography (CT) scan showed no sign about cerebral hemorrhage symptoms, and brain magnetic resonance imaging (MRI) showed acute ischemic infarct in the left territory. The patient confirmed a diagnosis of acute cerebral infarction following a T. stejnegeri bite.

INTERVENTIONS

The patient received an injection of polyvalent anti-snake venom serum, neuroprotective therapy, and anti-platelet aggregate treatment.

OUTCOMES

At the 3-month follow-up visit, the patient's left lower extremity swelling disappeared, the right limb muscle strength recovered, and the modified Rankin scale (mRS) score was 4 points.

LESSONS

The patient was diagnosed with acute ischemic infarct interrelated to snake bite; further investigations were needed to ascertain mechanism. The clinicians should pay more attention to identify potential victims of neurologic complications, to reduce the mortality rate of snake bite.

Acute Reversible Ischemic Stroke after Snake Bite

Snake bite is very common in India. Ischemic stroke after snake bite has been described in the literature sparsely. Furthermore, the onset of stroke and its clinical reversibility is a rarity. Here, we present a case of snake bite with ischemic stroke which has clinically reversible outcome.

A rare case report of Russell’s viper snakebite with ischemic stroke

Ischemic stroke following snakebite is rare. We report a case of a 55-year-old male who developed headache with expressive aphasia following a Russell’s viper bite. Computed tomography scan of the brain revealed infarcts in bilateral frontal lobes. The possible mechanisms for cerebral infarction in this scenario are discussed, which include disseminated intravascular coagulation, toxin-induced vasculitis, and endothelial damage. In viper bites, whenever there is any central nervous system manifestations or deficits, immediate computed tomography scan of the brain should be taken to delineate the underlying pathology, whether hemorrhagic or ischemic, as treatments differ in both situations. Although ischemic stroke is rare in viper bites, if the treatment is started early, the neurological deficits can be minimized.

Brainstem ischemic stroke after to Bothrops atrox snakebite

We report case of a 48 years old woman bitten on her right foot by a Bothrops atrox viper. As a result, she developed a severe coagulopathy which improved with application of polyvalent antivenom. Four days after bite she suffered a devastating brainstem ischemic stroke. Possible pathogenetic mechanisms are discussed.

Posterior circulation ischemic stroke following Russell's viper envenomation

Ischemic stroke following viper bite is rare. We report a case of posterior circulation ischemic infarction following viper bite in a previously healthy woman. Soon after being bitten by the snake on the left leg, she developed local redness, echymosis and one hour later became drowsy. On examination she had skew deviation of eyes and down gaze preference, generalized hypotonia. A CT scan of brain showed infarcts in cerebellar hemispheres and occipital lobes on both sides and that was confirmed on magnetic resonance imaging of brain. Her coagulation profile was deranged. Most common and serious central nervous system complication following snake bite is intracranial hemorrhage. Ischemic stroke commonly involves anterior circulation. Bilateral cerebellar and occipital infraction is not yet reported in literature. Exact cause for the development of infarction is not clear. The possible mechanisms of infarction in this scenario are discussed. Patient was treated with anti-snake venom and showed a good recovery. Early imaging and early treatment with anti-snake venom is important for a favorable outcome.

Cerebellar infarct with neurogenic pulmonary edema following viper bite

Russell's viper (Daboia russelli) bites are well known to cause bleeding complications. However, thrombotic complications are rare. We present the case details of a female who was bitten by a Russell's viper (Daboia russelli) in her village. She then developed features of envenomation in the form of hemorrhagic episodes. She received 27 vials of polyvalent anti-snake venom to which the hemorrhagic complications responded. After about 48 h of the bite she developed features of cerebellar infarct along with pulmonary edema which was in all probability neurogenic in origin. She was managed with mechanical ventilation and extra ventricular drainage with good recovery. We discuss the likely pathogenesis of the infarct and pulmonary edema occurring in a patient with viper bite and other features of envenomation.

Acute ischemic stroke following Hump-nosed viper envenoming; first authenticated case

Hump-nosed pit viper (Genus Hypnale) is a medically important venomous snake in Sri Lanka and Southwestern India which causes significant morbidity and mortality. Envenoming of this snake results in hemostastic dysfunction, thrombotic microangiopathy, acute kidney injury and death. This case describes an authenticated first case of ischemic stroke in a 65 year old male following envenoming by H.hypnale in Sri Lanka.

Renal cortical necrosis, peripheral gangrene, perinephric and retroperitoneal haematoma in a patient with a viper bite

Snakebites are estimated to affect more than 2.5 million people annually, of whom more than 100,000 die. Viper bites cause various systemic symptoms such as: coagulopathy; haemolysis; acute renal failure; a generalized increase in capillary permeability; rhabdomyolysis; and neurotoxicity. Wide spectrums of vascular complications are seen. We report the case of a patient developing gangrenous changes in a lower limb along with the development of perinepheric and retroperitoneal haematoma with acute cortical necrosis of the kidneys.

Infant death after nose-horned viper (Vipera ammodytes ammodytes) bite in Croatia: A case report

A case of a 45-day-old male infant, bitten on the neck by nose-horned viper (Vipera ammodytes ammodytes), is reported. This episode occurred while the baby was on a picnic with his parents in a hill near a town in southern Croatia. In spite of immediate arrival at hospital, where antivenom was administrated and all the necessary treatment measures were carried out, the infant died 6 h following the bite. The cause of death was severe and progressive hyperkalaemia, massive intravascular haemolysis, severe coagulopathy and myocardial dysfunction.

Stroke in Latin America

Stroke is one of the leading causes of mortality in Latin America, with variable incidence and prevalence throughout the continent reflecting regional socioeconomic differences. In Latin America, uncontrolled hypertension is one of the major causes of stroke, but other modifiable risk factors also play a role, such as heavy alcohol consumption and smoking. Intracerebral hemorrhage and lacunar stroke are more frequent in Latin America than in North America and Europe. There are multiple causes of stroke that are endemic to Latin America, including neurocysticercosis, Chagas' disease, sickle cell anemia, malaria, hemorrhagic fever, and snake bites.

Snake venoms and coagulopathy

Snakebite affects around 2.5 million humans annually, with greater than 100,000 deaths. Coagulopathy is a significant cause of both morbidity and mortality in these patients, either directly, or indirectly. This paper reviews clinical aspects of snakebite coagulopathy, including types of coagulopathy (procoagulant, fibrinogen clotting, fibrinolytic, platelet-active, anticoagulant, thrombotic, haemorrhagic), diagnosis and treatment. Examples of clinical laboratory findings in selected types of snakebite coagulopathy are presented. Where available, antivenom is the most effective treatment, while standard treatments for other forms of coagulopathy, such as factor replacement therapy and heparin, are either ineffective or dangerous in snakebite coagulopathy, except in specific situations.

Multiple thrombotic occlusions of vessels after Russell's viper envenoming

Systemic bleeding due to consumption coagulopathy and thrombocytopenia due to activation of procoagulants is the leading manifestation and cause of death in Russell's viper systemic envenoming. Thrombotic occlusion of the blood vessels is rare in cases of snakebite. In this report, two adult patients with Russell's viper systemic envenoming presented multiple cerebral infarctions, digital gangrenes and ischaemic organs in addition to typical clinical manifestations of bleeding diathesis and renal involvement. Our findings in these two special cases suggest that the venom-induced coagulopathy and endothelium damage, predisposed by toxin-induced vasoconstriction, might be the possible mechanism of multiple thrombotic vascular occlusions in systemic envenoming of Formosan Russell's viper.

Fatal cerebral hemorrhage and acute renal failure after young Bothrops jararacussu snake bite

An unusual case of a patient developing severe coagulopathy disorder and a clinical picture of cerebral hemorrhage and acute renal failure after young Bothrops jararacussu snake bite is reported. The mechanisms of snake venom-induced injury are discussed and similar cases in literature are revised and compared. The use of bothropic-Crotalus antivenom in severe B. jararacussu envenomation is discussed.