Lab

Skin Test for Horse Serum Sensitivity

search

Skin Test for Horse Serum Sensitivity, Horse Serum Sensitivity

  • Indication
  1. Many antitoxins and antivenins are from horse serum (e.g. original Diphtheria antitoxin)
  2. Skin Test for Horse Serum Sensitivity prior to use
    1. Rarely performed now
  1. No study (including Skin Test for Horse Serum Sensitivity) predicts Serum Sickness reaction
    1. Tantawichien (1995) Clin Infect Dis 21(3): 660 +PMID: 8527562 [PubMed]
  1. Previously indicated with older ACP antivenoms in which reactions were much more common
    1. Newer antivenoms (e.g. CroFab) have lower Incidence of reaction, and Skin Testing is not typically done
  2. Advantages to performing skin test prior to antivenin
    1. Possible medicolegal protection only
  3. Disadvantages to skin test prior to antitoxin
    1. Delays treatment (antitoxin administration)
    2. High false-positive rate: 33%
    3. High false-negative rate: 10 to 36%
    4. Has resulted in Anaphylaxis in some patients
  4. References
    1. Jurkovich (1998) J Trauma 28:1032-7 [PubMed]
  • Technique
  1. 0.1 ml of 1:10 dilution of antitoxin intradermal
  2. Inject at Forearm with 27 gauge
  1. Local reaction
    1. Hyperemic areola at injection site > 0.5 cm
  2. Systemic reaction
    1. Fever, chills
    2. Hypotension with decrease Blood Pressure >20 mmHg
    3. Skin rash
    4. Respiratory difficulty
    5. Nausea, Vomiting
    6. Generalized itching
  • Interpretation
  • If any signs of reaction
  1. Suggests Horse Serum Sensitivity
  2. Do not use antitoxin