Drug Allergy Issues - Essay Example

After 4 days of discontinuation of the antibiotics, the patient became tachypnoeic with a rise in the neutrophil count and a fever of 102 degrees Fahrenheit and the appearance of a pulmonary infiltrate. The initial therapeutic course was uneventful. Although the patient has a history of childhood penicillin allergy, no penicillin drug was utilized for this illness, and therefore, it can be taken for granted that there was no previous exposure to this illness, and it has appeared following several treatment days. These allergic drug reactions usually subside after discontinuation of the drug. The only point against this diagnosis is the absence of peripheral blood eosinophilia (Van Arsdel, Jr., 1982). This reaction can be classified as an unpredictable reaction since it is evident that this happened in a dose-independent fashion without any relation to the pharmacological action of these agents. This could be one of the three, idiosyncratic reactions, allergic reactions, or pseudoallergic reactions. Thus following the discontinuation of the drugs, there is a possibility of the development of drug-specific IgE antibodies which might have been responsible for nonspecific mast cell release. However, in this patient, it looks like it is a drug fever with organ-specific reactions that may indicate a multifactorial origin. Due to this allergic reaction, the patient developed pneumonitis, and there is the immense possibility that the renal failure that continued is an enhancement of baseline renal failure on which renal reactions of drug allergy had been superimposed. Most probably these drugs could have produced univalent chemical compounds as a result of phase I reactions, and these might have been activated to trigger the immune response with elimination affected by renal failure. In all probability, these molecules could have been bound to cell surface molecules or serum proteins to produce the reactions of pneumonitis and fever.

Despite getting 48 hours of antibiotic therapy involving all three agents that she had been treated before, the fever did not resolve. This indicates that the fever was not due to infection, nor were the pulmonary infiltrates. This was due to the fact, although it is not known in this case, which agent is the cause, given her renal function compromise, most probably, it was a multi-agent infection. Most likely, this patient had a pseudoallergic reaction since there is no evidence of an immunologic mechanism involved evidenced by no rise in eosinophil count. At this phase, it can also be a possibility that the patient has multiple drug allergy syndrome, which is the propensity to develop immune reactions to haptens and then to express a broad range of immunopathologic responses. Since the patient has a penicillin allergy, she is more likely to develop other allergies to a second unrelated agent. Patients with penicillin allergy may develop an allergy to an unrelated compound or non-beta-lactam antibiotic or even multiple agents (Asero, 2001), and it is prevalent in 21% of these patients. The drugs which she was treated were metronidazole, vancomycin, and levofloxacin, and these are unrelated chemically or immunologically to penicillin, and in this way, she has more propensities to react more frequently to drug haptens to lead to multiple drug allergy syndromes (Gruchalla, 2000). Another important feature of her reaction is that there is a probability of continuation of her symptoms despite discontinuation of the drug due to the formation of drug metabolites that are haptenic and get covalently linked to cell surface proteins. These were creating her fever and the infiltrate.