Diagnostic reagents in drug allergy: immunochemical specificity in the 1,2-diphenyl-pyrazolidinedione series.

Chemically defined haptenic reagents and haptenic conjugates were synthesized to be used for skin tests in allergic patients and for serological tests. One series of reagents is based on an open-chain derivative which is formed by reaction of the oxidation product of phenylbutazone, 4-hydroxyphenylbutazone, with amino functions. A second series uses the intact 1,2-diphenyl-pyrazolidine-3,5-dione molecule which is substituted in the 4-position with acetic acid. Both haptens are used in conjunction with spacer molecules which provide considerable distances between haptenic moiety and carriers. The skin test reagents are hexavalent conjugates based on the bis-penta-L-lysine carrier "PAL". Rabbit and guinea-pig antisera against the haptens were obtained by immunizations with human serum albumin conjugates. Data obtained from passive cutaneous anaphylaxis and from ELISA tests show that there is generally only slight cross-reactivity between the two series of haptenic reagents. Also, there is only modest cross-reactivity between intact drugs and haptenic reagents. No measurable crossreactions were noted between 1-phenyl-2,3-dimethyl-3-pyrazolin-5-one derivatives and haptenic reagents of the 1,2-diphenyl-pyrazolidinedione series.

[Immune reactions in pseudo-lupus-syndrome. A long-term study (author's transl)]. / Immunreaktionen beim Pseudo-Lupus-Syndrom. Eine Langzeitstudie.

23 patients with proven pseudolupus-syndrome were observed over a period of five years; titers of specific antimitochondrial antibodies (AMA) were tested in a follow-up study after the last intake of Venopyronum-Dragees (VPD), a drug combination of plant glycosides, horse-chestnut extracts and phenopyrazone. Cellular immune reactions against the eliciting drug, depended on the date of the acute phase and were examined in two patients after reexposure. High titers in the acute phase decreased rapidly in most of the cases within the first six months. After reexposure with VPD, AMA rose within three days up to the five fold compared with the initial titer. Only the analgetic component of VPD, phenopyrazone, was able to induce a significant increase of AMA-titer after reexposure. A specific cellular sensitivity to this substance could be demonstrated by lymphocyte stimulation in the presence of a phenopyrazone containing drug preparation. There was no chronic course of the disease; clinical exazerbation could be observed only after new intake of the drug. The analysis of drug history shows, that other pyrazolone containing drugs may also be able to induce a pseudolupus-syndrome.