Coombs and Gell

Penicillins and cephalosporins are prototypes for allergic reactions of type I by the classification of Coombs and Gell (1963), based on the pathogenetic mechanisms. They are mostly IgE mediated. But type III and type IV reactions also occur. 

Coombs and Gell (1963) have classified all immunologic (allergic) reactions into four types (I to IV). The classification of Types I to III depends on whether antigen or antibody is cell-fixed or in solution. Type IV is cell-mediated and is typified in the skin by responses such as the tuberculin reaction which develops macroscopically over 36-48 hr and lasts for 72-96 hours. This is the classical delayed hypersensitivity reaction. 

Coombs, R.R.A. and Gell, P.G.H. (1975). Classification of allergic reactions responsible for clinical hypersensitivity and disease. In Clinical Aspects of Immunology. (Gell, P.G.H., Coombs, R.R.A. and Lachman, D.J., Eds.). Blackwell Scientific Publications, Oxford, p. 761. 

Conston AS (1974) Hypersensitivity myocarditis a fatal reaction. J Med Soc NJ 71 61 Coombs RRA, Gell GPH (1953) Classification of allergic reactions responsible for clinical hypersensitivity and disease. In Gell PG, Coombs RRA (eds) Clinical aspects of immunology. Blackwell Scientific, Oxford, pp 575-596... 

Hypersensitivity reactions with P-lactam antibiotics, especially penicillin, may encompass any of the type I through IV Gell-Coombs classifications. The most common reactions are maculopapular and urticarial eruptions.7 While rare (less than 0.05%), anaphylaxis to penicillins causes the greatest concern because they are responsible for the majority of drug-induced anaphylaxis deaths in patients, accounting for 75% of all ana-i phylaxis cases in the United States.5,8 The treatment of ana-I phylaxis is given in Table 51-2.9... 

Source Based on classification system of Gell and Coombs, 1967. 

According to the Gell and Coombs classification, allergy Type II is called antibody-mediated cytotoxicity . It is triggered by excessive destruction of... 

TABLE 32.7. Gell and Coombs Classification of Hypersensitivity Reactions... 

Traditionally, the classification scheme defined by Gell and Coombs (206) distinguishes four types of reactions ... 

Haptens or prohaptens can induce type I to IV immune reactions (Gell and Coombs classification)9 IgE-mediated drug hypersensitivity (type I), IgG-mediated... 

On the basis of the highly influential Gell and Coombs classification scheme, there are four categories of hypersensitivity. 

It is classical to divide allergic reactions into four types according to the classification of Gells and Coombs (1962). Whereas this classification may still appear valid as far as some of the initial triggering events of allergic or immunologically mediated reactions are concerned, it has become obvious that it represents a rather simplistic approach to the complex reality of immunologically mediated reactions in tissues. 

Interaction of antibodies, especially of the IgM and IgG type, with antigenic determinants present on the membrane of target cells, followed by classical activation of complement (Gell/Coombs type II). 

Morrison-Smith J, Gell PGH (1975) Serum sickness and acute anaphylaxis in man. In Gell PGH, Coombs RRA, Lachmnann PJ (eds) Chnical aspects of immunology, 3rd edn. Blackwell, Oxford, p 903... 

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