Spider bites: Difference between revisions

 
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==Types==
==Background==
*[[Brown recluse spider bite]]
*Standard [[abscess]] are not typically due to spider bites and should not be diagnosed as such
*[[Black widow spider bite]]
*[[Tarantula spider bite]]


===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===
<gallery mode="packed">
<gallery mode="packed">
File:Tarantula640px-Brachypelma smithi 2009 G03.jpg|[[Tarantula]]
File:Tarantula640px-Brachypelma smithi 2009 G03.jpg|[[Tarantula]]
File:Western Black Widow (Latrodectus hesperus).jpg|[[Black widow spider]]
File:Western Black Widow (Latrodectus hesperus).jpg|[[Black widow spider]]
File:Brown Recluse.jpg|[[Brown recluse]]
File:Brown Recluse.jpg|[[Brown recluse]]
File:p nigreventer.jpeg|[[Armed spider]] (''phoneutria nigreventer'')
File:Funnel Web Spider.png|[[Funnel-web spider]] (Hadronyche versuta)
</gallery>
</gallery>
==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==
==Differential Diagnosis==
{{Bites and stings DDX}}
{{Bites and stings DDX}}


==Review Questions==
==Evaluation==
<quiz display=simple>
===Workup===
{Environmental emergencies question – Regarding black widow and brown recluse spider envenomations, which of the following is FALSE?
 
|type="()"}
===Diagnosis===
-Black widow spiders (BWS) are found in the temperate regions of six continents and are widespread through North America, including the western United States (California included).
*Typically a clinical diagnosis
-Signs and symptoms associated with BWS (e.g. diffuse pain, muscle cramps, tachycardia, and hypertension) usually develop begin within 30 to 120 minutes of the envenomation.
 
-After antivenom for BWS is administered, symptoms typically resolve within 30 minutes, with complete relief within 2 hours.
==Management==
+Brown recluse spider (BRS) envenomation is most common in west coast states, such as California.
* Clean area of bite
||'''Harwood-Nuss – 1734-1739. Although BWS occur in Southern California, BRS are most common in the southern Midwestern states (but not California). Note that BRS have more local toxicity with eschar formation and necrosis, and these should not be debrided or excised. BRS may result in hemolysis and rhabdomyolysis. There is no antivenom available for BRS in the US, but there is one for BWS, which manifest severe life-threatening systemic signs.'''
* [[Tetanus prophylaxis]]
-Most bites from BRS have a benign clinical course, but necrosis with induration and eschar formation may occur, and systemic effects, such as fever, chills, headache, malaise, arthralgia, and myalgias progress after more than 24 to 48 hours and resolve by 72 to 96 hours post bite.
* [[analgesia|Analgesics]]
</quiz>
* 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==




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*[[Bites and Stings]]
*[[Bites and Stings]]


===Sources===
==External Links==
 
 
==References==
<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.


[[Category:Environ]]
[[Category:Environmental]]
[[Category:Toxicology]]

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

Visual Spider Identification

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

Differential Diagnosis

Envenomations, bites and stings

Evaluation

Workup

Diagnosis

  • Typically a clinical diagnosis

Management

Disposition

See Also

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.