Spider bite envenomation in Al Baha Region, Saudi Arabia

Black widow spider bites experience from tertiary care center in Saudi Arabia

INTRODUCTION

Black widow spiders are one of the most poisonous species to humans; there are more than 30 species of widow spiders in the globe but good thing that not all of them are dangerous. Some of these spiders produce toxic venoms, which cause broad spectrum of clinical manifestations including skin lesions, neurotoxicity, cardiac toxicity and death in some occasions. In Saudi Arabia there were no much reports of black widow spider bites apart from the case series by BUCUR and his group in ALBAHA region.

SETTINGS

In 2 years period a total of 8 patients were presented to the emergency departments diagnosed to have black widow spider bites based on description by the patients.

RESULTS

100 % of the cohort were males, aged between 25-58 years. The time between bite and presentation to emergency room was one hour in average (30 min to 4 hours). 75% occured during summer season. All of them 100% had one bite only and reported the bite to be at nighttime in 75% of the times. The average pain score at presentation was 4 /10.100% of the bites were in the lower extremities and almost all progressed to have lower back pain. Three patients had gastrointestinal tract manifestation in form of abdominal cramps and nausea. One had bilateral ptosis, none of them had cardiac or pulmonary complications. The outcome was excellent in all patients and the average of hospital stay was 2.5 days (1-5).

Reversible Myocarditis and Pericarditis after Black Widow Spider Bite or Kounis Syndrome?

Clinical manifestation of black widow spider bite is variable and occasionally leads to death in rural areas. Cases of myocarditis and pericarditis after black widow spider bite are rare and the associated prognostic significance is unknown. Kounis syndrome has been defined as an acute coronary syndrome in the setting of allergic or hypersensitivity and anaphylactic or anaphylactoid insults that manifests as vasospastic angina or acute myocardial infarction or stent thrombosis. Allergic myocarditis is caused by myocardial inflammation triggered by infectious pathogens, toxic, ischemic, or mechanical injuries, such as drug-related inflammation and other immune reactions. A 15-year-old child was admitted to the emergency department with pulmonary edema after spider bite. ST segment depression on ECG, elevated cardiac enzymes and global left ventricular hypokinesia (with ejection fraction of 22%), and local pericardial effusion findings confirmed the diagnosis of myopericarditis. After heart failure and pulmonary edema oriented medical therapy, clinical status improved. Patient showed a progressive improvement and LV functions returned to normal on the sixth day. Myopericarditis complicating spider bite is rare and sometimes fatal. The mechanism is not clearly known. Alpha-latrotoxin of the black widow spider is mostly convicted in these cases. But allergy or hypersensitivity may play a role in myocardial damage.

Reversible myocarditis after black widow spider envenomation

Black widow spiders can cause variable clinical scenarios from local damage to very serious conditions including death. Acute myocardial damage is rarely observed and its prognostic significance is not known. We report a rare case of a 35-year-old man who developed an acute myocarditis with cardiogenic pulmonary edema requiring mechanical ventilation caused by black widow spider's envenomation. The patient was previously healthy. The clinical course was associated with systemic and cardiovascular complaints. His electrocardiogram revealed ST-segment elevation with T-wave amplitude. The plasma concentrations of cardiac enzymes were elevated. His first echocardiography showed hypokinesis of the left ventricle (left ventricle ejection fraction 48%). Magnetic resonance imaging showed also focal myocardial injury of the LV. There was progressive improvement in cardiac traces, biochemical and echocardiographical values (second left ventricle ejection fraction increased to 50%). Myocardial involvement after a spider bite is rare and can cause death. The exact mechanism of this myocarditis is unknown. We report a rare case of acute myocarditis with cardiogenic pulmonary edema requiring mechanical ventilation caused by black widow spider's envenomation. We objectively documented progressive clinical and electrical improvement.