D2.257 - Anaphylaxis with FOLFOX scheme: not everything is Oxaliplatin

Folates, as water-soluble vitamins, are directly involved both in the synthesis and repair of genetic material and in the formation of amino acids and are therefore indispensable for intracellular metabolism itself. Currently, it has been demonstrated that the administration of 5-FU/folinic acid plus oxaliplatin significantly improves the clinical situation, treatment response and survival of patients with colorectal cancer due to greater tolerability, thus making the incorporation of 5-FU/folinic acid a first-line adjuvant standard for the treatment of colorectal cancer.

We present the case of a 73 year old woman diagnosed with stage IV colorectal carcinoma with lymph node and cervical metastases who during the infusion of cycle 9 of FOLFOX (Folinic acid, Fluorouracil and Oxaliplatin) presented generalized pruritus with dyspnea and wheezing. The infusion was immediately stopped and Methylprednisolone 80 mg and Dexchlorpheniramine 5mg were administered, improving the cynic in one hour. In view of the suspicion of a possible allergic reaction to Oxaliplatin and after improvement of the patient, the infusion was restarted only with Folinic Acid and Fluorouracil starting after 5 minutes with pruritus, generalized urticaria and dyspnea with wheezing. The infusion was stopped and the patient received again medication with corticosteroids and antihistamines. 

The allergological study included skin tests with prick test and intradermal reaction with Oxaliplatin (0.5 and 5 mg/ml), Folinic acid (30 and 300 mg/ml) and 5 Fluorouracil (0.5, 5 and 50 mg/ml) being the result positive for Folinic acid at the first concentration (15x8mm, Histamine: 5 mm). Controls were performed in 10 patients (5 atopic and 5 non-atopic patients). Blood was drawn at the acute moment of the reaction to measure serum tryptase, which was 73.5 ug/L. Anaphylaxis due to hypersensitivity to folinic acid was diagnosed. As there was no other current treatment alternative, it was decided to perform a rapid desensitization regimen for folinic acid (417.6 mg) in 1 bag of 250 ml of saline solution with 7 steps. Desensitization was successfully completed and the patient was able to receive her first line of treatment.

The complexity of regimens with various chemotherapeutic agents makes diagnosis difficult, so it is necessary to be systematic and test all drugs administered during chemotherapy without underestimating the less common drugs in hypersensitivity reactions to chemotherapeutics.