Antisera and Immuneglobulins

ANTISERA AND IMMUNEGLOBULINS

Antisera are purified and concentrated preparations of serum of horses actively immunized against a specific antigen.

Immediate type of allergic reactions (urticaria, angioedema, respiratory distress, anaphylaxis) can occur with any antiserum; adrenaline (1:1000 amp.) should be at hand while injecting them. Prior to each administration, history of reaction to any ‘serum’ preparation should be elicited and an intracutaneous/scratch test should be performed. A positive test contraindicates administration but a negative test does not completely rule out systemic sensitivity.

Serum sickness with fever, rash, joint pain, lymphadenopathy appearing 7–12 days later is more frequent after large doses and repeated administration. An overall incidence of 5–10% is reported.

Local pain, erythema and arthus type reaction without constitutional symptoms may also occur 7–10 days after i.m. injection.

Immuneglobulins (IGs) are separated human gamma globulins which carry the antibodies. These may be nonspecific (normal) or specific (hyperimmune) against a particular antigen. These are more efficacious than the corresponding antisera. Hypersensitivity reactions are very rare with IGs. Skin tests may be misleading and are not needed. However, large doses and repeated injections do increase risk; adrenaline should be available. Transient local tenderness and stiffness of injected muscle is occasional. Serum sickness does not occur with human IGs.

Antisera (From Horse)

Tetanus antitoxin (ATS)

Gas gangrene antitoxin (AGS)

Diphtheria antitoxin (ADS)

Antirabies serum (ARS)

Antisnake venom polyvalent

Immuneglobulins (human)

Normal human gamma globulin

Anti-D immuneglobulin

Tetanus immuneglobulin

Rabies immuneglobulin

Hepatitis-B immuneglobulin

Normal Human Gamma Globulin

It is concentrated IG obtained by fractionation in cold from pooled human plasma. Indications for its use are—viral hepatitis A and B (prophylaxis), measles, mumps, poliomyelitis and chickenpox (prophylaxis and modification of course of illness), and has some beneficial action in burns. It is especially valuable in agammaglobulinemia, premature infants and in patients of leukemia or those undergoing immuno-suppression. It can augment the response to antibiotics in debilitated patients with bacterial infections.

Dose: 0.02–1 ml/kg i.m. for different indications.

GAMMALIN, GLOBUNAL, Sii GAMMA GLOBULIN, GAMAFINE 10%, 16.5% injection in 1, 2 ml amps.

An intravenous preparation (Sii I.V.GG 0.1–0.4 g/ kg/day) has been made available for conditions requiring high doses which cannot be injected i.m.

Anti-D Immuneglobulin.

Tetanus

Tetanus Immuneglobulin (Human): It is indicated for prophylaxis in non-immunized persons receiving a contaminated wound who are at high risk of developing tetanus. The t½ of this antitoxin is 4 weeks and significant blood levels are maintained for upto 14 weeks. It is more efficacious and longer acting than the equine antitoxin (ATS). If tetanus toxoid is given at the same time (but at a different site), development of primary immune response to the toxoid is not interfered with. It has also been used for the treatment of clinical tetanus, but the efficacy is variable. Intrathecal administration has also been tried.

Dose: prophylactic 250–500 IU, therapeutic 3000–6000 IU i.m. and/or 250500 IU intrathecal.

Sii TIG 250 IU (liquid), 500 IU (lyophilized), TETNAL 250 IU/2 ml inj., TETAGAM 250 IU/ml inj.

Tetanus Antitoxin (Antitetanic Serum, ATS): It is obtained from horse; is inferior to human antitoxin and should be used for the above indications only when tetanus immuneglobulin is not available.

Dose: prophylactic 1500–3000 IU, i.m. or s.c.; therapeutic 50,000–100,000 IU part i.v. and rest i.m.

TETANUS ANTITOXIN 750 IU, 1500 IU, 5000 IU, 10,000 IU, 20,000 IU, and 50,000 IU in 1–10 ml ampoules. TETANUS IMMUNE SERUM (enzyme refined, equine) 10,000 and 20,000 IU vials.

Rabies

Antirabies serum (ARS): Also called ‘equine rabies immuneglobulin ’ (ERIG) is refined, concentrated and lyophilized serum from horses hyperimmunized by repeated injections of fixed rabies virus. It is indicated promptly after suspected exposure and is given simultaneously with rabies vaccine to nonimmunized individuals.

Dose—40 IU/kg infiltrated round the wound and excess is injected i.m.; single dose at the initiation of antirabic therapy along with rabies vaccine. It is inferior to HRIG and should be used only when HRIG is not available.

IMORAB 1000 IU/5 ml inj.

Rabies Immuneglobulin Human (HRIG): It is used in the same manner as ARS and is superior to it with longer t½.

Dose—20 IU/kg, on day 0 only, infiltrated round the bite; excess may be injected i.m. elsewhere. Passive protection with HRIG or ARS is needed because active immunity takes 2 or more weeks to develop.

BERIR ABP 300 IU/2 ml and 750 IU/5 ml inj; RABGLOB 300 IU/2 ml inj.

Hepatitis B Immuneglobulin

It is 10–18% solution of human IG containing a high titer of antibody to hepatitis B surface antigen. It is a better prophylactic than normal human gamma globulin: indicated in individuals acutely exposed to HBsAg positive blood or blood products. Hepatitis B vaccine should be given concurrently.

Dose: 1000–2000 IU (adults), 32–48 IU/kg (children) to be administered within 7 days of exposure.

HEPAGLOB 100 IU (0.5 ml) 200 IU (1 ml) per vial for i.m. inj.

Diphtheria Antitoxin (Antidiphtheritic Serum ADS)

It is obtained from horse and is used therapeutically in clinical diphtheria without waiting for bacteriological report, because each hour’s delay increases the dose requirement and decreases beneficial effects: damage already caused by the toxin is not reversed. The antitoxin neutralizes the exotoxin released at the site of infection and that circulating in blood but not that fixed to tissues.

Dose: 20,000–40,000 IU i.m. or i.v. for pharyngeal/ laryngeal disease of upto 48 hour duration. Higher dose (upto 100,000 IU may be needed).

DIPHTHERIA ANTITOXIN 10,000 IU in 10 ml amp.

Appropriate antimicrobials should also be given. Unprotected child contacts should be given ADS (1000 IU) along with diphtheria toxoid for prophylaxis.

Gas Gangrene Antitoxin (Anti Gas Gangrene Serum, AGS)

It is enzyme refined equine antitoxin against Cl. edematiens, Cl. perfringens and Cl. septicum.

Dose: prophylactic 10,000 IU; therapeutic 30,000–75,000 IU s.c./i.m./i.v.

AGGS 10,000 IU amp.

Antisnake Venom (ASV) Serum Polyvalent

It is available as purified, enzyme refined and concentrated equine globulins in lyophilized vials with 10 ml ampule of distilled water. After reconstitution, each ml neutralizes:

0.6 mg of standard Cobra (Naja naja) venom.

0.6 mg of standard Russel’s viper (Vipera russelli) venom.

0.45  g of standard Sawscaled viper (Echis carinatus) venom.

0.45 mg of standard Krait (Bungarus caeruleus) venom.

ANTISNAKE VENOM SERUM POLYVALENT, ASVS

Dose: 20 ml i.v. (1 ml/min injection) repeated at 1–6 hourly intervals till symptoms of envenomation disappear: upto 300 ml may be required in viper bites, while still larger amounts (upto 900 ml) have been used in cobra bites, but it is important to continue ASV treatment till evidence of envenomation persists. In case of viper bite some serum should also be infiltrated around the site to prevent venom induced gangrene.

Allergic reactions, including anaphylactic shock, to the serum are possible. When time permits, sensitivity test should be done; otherwise adrenaline may be injected s.c. concurrently. An antihistaminic and a glucocorticoid may also be given prophylactically.