Spider bites: Difference between revisions

Latest revision as of 13:28, 29 May 2022

Background

Standard abscess are not typically due to spider bites and should not be diagnosed as such

Clinically important spider genera by geographic region

North America
- Loxosceles (e.g. brown recluse)
- Latrodectus (e.g. black widow)
- Tegenaria
South America
- Loxosceles
- Latrodectus
- Phoneutria (e.g. armed spider)
Africa
- Loxosceles
- Latrodectus
Europe
- Loxosceles
- Latrodectus
Australia
- Atrax (e.g. funnel-web spider)
- Hadronyche (e.g. funnel-web spider)
- Latrodectus
Asia
- Latrodectus
Other
- Tarantula spider bite

Visual Spider Identification

Tarantula
Black widow spider
Brown recluse
Armed spider (phoneutria nigreventer)
Funnel-web spider (Hadronyche versuta)

Clinical Features

History

Determine circumstances of bite to assess consistency with spider habitat and behavior
- Indoors vs outdoors
- Day vs night
- Geographic location (recent travel)
Appearance of the spider if seen
Dead spiders can be preserved in 70% EtOH and later identified by arachnologists or entomologist

Physical Exam

No pathognomonic signs proving lesion is a spider bite
Assess both bite site and for systemic signs
Bite Site
- Location
  - Spider bites more common when clothing is tight against skin
- Number of bites
  - Multiple bites suggest parasitic insect and not spider
- Appearance of bite
  - Erythema, pallor, hemorrhage, induration, tenderness, paresthesia, vesicles
Systemic findings
- Abnormal vital signs (tachycardia possible with black widow)
- Altered mental status
- Abdominal pain
- Diaphoresis
- Generalized rash
- Muscle fasciculations, spasm, or tenderness

Differential Diagnosis

Envenomations, bites and stings

Hymenoptera stings (bees, wasps, ants)
Mammalian bites
- Closed fist infection (Fight bite)
- Dog bite
Marine toxins and envenomations
- Toxins (ciguatera, neurotoxic shellfish poisoning, paralytic shellfish poisoning, scombroid, tetrodotoxin
- Stingers (stingray injury)
- Venomous fish (catfish, zebrafish, scorpion fish, stonefish, cone shells, lionfish, sea urchins)
- Nematocysts (coral reef, fire coral, box jellyfish, sea wasp, portuguese man-of-war, sea anemones)
- Phylum porifera (sponges)
- Bites (alligator/crocodile, octopus, shark)
Scorpion envenomation
Reptile envenomation
- Snake bites
  - Crotaline (Pit Vipers)
  - Elapidae (Coral Snakes)
- Lizard bites
Spider bites

Evaluation

Workup

Diagnosis

Typically a clinical diagnosis

Management

Clean area of bite
Tetanus prophylaxis
Analgesics
Hydration
Surgical follow up if indicated for debridement of necrotic area
Antivenin is indicated only for specific envenomation
No proven benefit for corticosteroids
No indication for antibiotics unless concern for cellulitis

Disposition

External Links

References

Boyer LV, Binford GJ, Degan JA. Spider Bites. In Auerbach PS, Cushing TA, Harris NS. Auerbach’s Wilderness Medicine. 7th ed. Philadelphia, PA: Elsevier; 2017: 993-1016.

Authors:

@@ Line 1: / Line 1: @@
-==Brown Recluse==
+==Background==
-===Clinical Features===
+*Standard [[abscess]] are not typically due to spider bites and should not be diagnosed as such
-#Bite is initially painless
-#Mild reaction
-##Most common
-##Mild erythematous lesion that later becomes firm and heals without scar
-#Severe reaction
-##Begins w/ mild-severe pain several hrs after bite accompanied by erythema and swelling
-##Hemorrhagic blister then forms surrounded by vasoconstriction-induced blanched skin
-##By day 3 or 4 hemorrhagic area may become ecchymotic
-###Leads to "red, white, and blue" sign (erythema, blanching, ecchymosis)
-##By end of first week ecchymotic area may become necrotic w/ eschar formation
-#Systemic effects
-##Rare
-##Occur predominantly in children 24-72hr after the bite
-###Include nausea/vomiting, fever, arthralgias, thrombocytopenia, rhabdo, renal failure
-===Treatment===
-#Local wound care
-#Abx are indicated only if signs of infection exist; secondary infections are uncommon
-== Black Widow ==
+===Clinically important spider genera by geographic region===
-=== Clinical Features ===
+* North America
-#Local
+** Loxosceles (e.g. [[brown recluse]])
-##Pinprick sensation; then increasing local pain that may spread to entire extremity
+** Latrodectus (e.g. [[black widow]])
-##Erythema appears 20-60 min after the bite
+** Tegenaria
-##Pain begins to abate after several hours and disappears by 2-3d
+* South America
-#Systemic
+** Loxosceles
-##Muscle cramp-like spasms in large muscle groups (although exam rarely reveals rigidity)
+** Latrodectus
-##Pain becomes generalized
+** [[Phoneutria]] (e.g. [[armed spider]])
-###Severe abdominal wall musculature pain and cramping
+* Africa
-##Headache, nausea/vomiting, diaphoresis, photophobia, dyspnea
+** Loxosceles
-##A-fib, myocarditis, priapism, and death are rare
+** Latrodectus
+* Europe
+** Loxosceles
+** Latrodectus
+* Australia
+** Atrax (e.g. [[funnel-web spider]])
+** Hadronyche (e.g. [[funnel-web spider]])
+** Latrodectus
+* Asia
+** Latrodectus
+*Other
+**[[Tarantula spider bite]]
-=== Treatment ===
+===Visual Spider Identification===
-#Pain and muscle spasms
+<gallery mode="packed">
-##Opiods and benzos
+File:Tarantula640px-Brachypelma smithi 2009 G03.jpg|[[Tarantula]]
-#Systemic illness
+File:Western Black Widow (Latrodectus hesperus).jpg|[[Black widow spider]]
-##Antivenom
+File:Brown Recluse.jpg|[[Brown recluse]]
-###Consider for:
+File:p nigreventer.jpeg|[[Armed spider]] (''phoneutria nigreventer'')
-####Children
+File:Funnel Web Spider.png|[[Funnel-web spider]] (Hadronyche versuta)
-####Pregnant women
+</gallery>
-####Elderly
-=== Disposition ===
+==Clinical Features==
-#Consider admission for:
+===History===
-##Symptoms of moderate envenomation
+* Determine circumstances of bite to assess consistency with spider habitat and behavior
-##Pregnant women
+** Indoors vs outdoors
-##Children
+** Day vs night
-##Pts w/ preexisting cardiovascular disease or HTN
+** Geographic location (recent travel)
+* Appearance of the spider if seen
+* Dead spiders can be preserved in 70% EtOH and later identified by arachnologists or entomologist
-==Tarantula==
+===Physical Exam===
-===Clinical Features===
+* No pathognomonic signs proving lesion is a spider bite
-#Abdominal hairs may be flicked a short distance when threatened
+* Assess both bite site and for systemic signs
-##Rarely penetrate human skin but can imbed deeply into conjunctiva and cornea
+* Bite Site
-#Bites can be painful but systemic symptoms other than fever are unusual
+** Location
+*** Spider bites more common when clothing is tight against skin
+** Number of bites
+*** Multiple bites suggest parasitic insect and not spider
+** Appearance of bite
+*** Erythema, pallor, hemorrhage, induration, tenderness, paresthesia, vesicles
+* Systemic findings
+** Abnormal vital signs ([[tachycardia]] possible with black widow)
+** [[Altered mental status]]
+** [[Abdominal pain]]
+** Diaphoresis
+** Generalized [[rash]]
+** Muscle fasciculations, spasm, or tenderness
+==Differential Diagnosis==
+{{Bites and stings DDX}}
+==Evaluation==
+===Workup===
+===Diagnosis===
+*Typically a clinical diagnosis
+==Management==
+* Clean area of bite
+* [[Tetanus prophylaxis]]
+* [[analgesia|Analgesics]]
+* Hydration
+* Surgical follow up if indicated for debridement of necrotic area
+* [[Antivenin]] is indicated only for specific envenomation
+* No proven benefit for [[corticosteroids]]
+* No indication for antibiotics unless concern for [[cellulitis]]
+==Disposition==
-===Management===
-#Red eye and pain after handling a tarantula necessitates an ocular exam
-##Hairs may be difficult to detect on slit lamp
-#Treatment is surgical removal of hairs and topical steroids
 ==See Also==
-[[Bites and Stings]]
+*[[Bites and Stings]]
+==External Links==
-==Source==
+==References==
-*Tintinalli
+<references/>
-*Rosen's
+* Boyer LV, Binford GJ, Degan JA. Spider Bites. In Auerbach PS, Cushing TA, Harris NS. Auerbach’s Wilderness Medicine. 7th ed. Philadelphia, PA: Elsevier; 2017: 993-1016.
-[[Category:Environ]]
+[[Category:Environmental]]
+[[Category:Toxicology]]