Types of Swelling after Immunization
1. Abscess – Sterile or Infective
Most of the time, mild swelling and pain that resolve within 2-3 days are not worrisome if baby is happy and playful. Most resolve with cold compress and analgesic.
Abscess: A fluctuant or draining fluid-filled lesion at the injection site usually seen with in 7 days of vaccination. It may or may not be accompanied by fever.
Sterile abscesses are typically not accompanied by fever. An abscess at the injection site is a rare local reaction.
Contamination of multidose vials can result in infection and abscess formations.
If the swelling becomes painful, tender and soft, see a Pediatrician.
Manage abscesses with analgesics (e.g., acetaminophen, and ice to injection site).
Incision and drainage of infected abscess may be required.
Sterile abscessPersists for more than 1 month, is more than 2.5 centimeters in diameter and/or drainage is evident; AND Material from the mass is known to be non-purulent; AND Absence of signs of localized inflammation (erythema, pain to light touch, warmth to touch) OR Failure to improve on antimicrobial therapy
Infected abscessPhysician-diagnosed; AND Material from the abscess is known to be purulent (positive gram stain or culture); OR There are one or more signs of localized inflammation (erythema, pain to light touch, warmth to touch); AND Evidence of improvement related to antimicrobial therapy.
Nodule: A nodule is a firm, small mass of tissue at the injection site with discrete or well demarcated borders in the absence of abscess formation, erythema and warmth. Nodules are mainly associated with aluminum-adsorbed vaccines, particularly if the dose is deposited subcutaneously rather then intramuscularly. Sterile nodules can take up to 1 year or more to resolve, they are rarely permanent.
Cellulitis: Erythema, tenderness and induration by the more intense erythema, tenderness to light touch and substantial local warmth.
For cases, it is advisable to consult your doctor before resolving to any diagnosis.
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