Allergic reaction to high-dose methotrexate

Anaphylactoid reaction to high-dose methotrexate and successful desensitization

Anaphylactic/anaphylactoid reaction to methotrexate (MTX) is uncommon. It may occur with the first dose (non-allergic reactions) or after a previous exposure to the drug (allergic or specific reactions). Desensitization has been shown effective in children with allergic-type reactions permitting the continuation of high-dose methotrexate (HDMTX) therapy. We report the case of a child with localized osteosarcoma who developed an anaphylactoid reaction after a first HDMTX course. A desensitization protocol was successfully applied allowing the administration of four additional courses. In our experience, desensitization can be a safe and effective procedure in children with anaphylactoid reactions to HDMTX.

Delayed renal excretion of methotrexate after a severe anaphylactic reaction to methotrexate in a child with osteosarcoma

Although methotrexate is an agent widely used in the practice of pediatric oncology, allergic reactions to methotrexate are most unusual. Most of these reactions typically occur after repeated administration. Here, we report a severe anaphylactoid reaction to the first dose of high-dose methotrexate infusion in a child with osteosarcoma who has also experienced a delayed excretion of methotrexate. Clinicians must be aware of the possibility of a systemic, near-fatal anaphylactic reactions with methotrexate and patients who experience severe anaphylactic reactions should be followed carefully because of the possibility of delayed methotrexate excretion.

Management and successful desensitization in methotrexate-induced anaphylaxis

Anaphylactic/anaphylactoid reactions to methotrexate are rare. In patients with methotrexate-induced anaphylaxis, discontinuation of treatment may increase the risk of death due to cancer progression. In such patients, desensitization may enable the patient to continue treatment with methotrexate. We report the case of a child with metastatic osteosarcoma, who experienced an anaphylactic/anaphylactoid reaction to methotrexate. Skin tests with methotrexate were not performed because their diagnostic value is controversial. Desensitization with methotrexate was successful and allowed the patient to complete 12 additional courses of chemotherapy. Thus, we confirm that desensitization may be a safe procedure in patients with cancer who experience methotrexate-induced anaphylaxis.

Anaphylactoid reaction to high-dose methotrexate and re-administration after a successful desensitization

Methotrexate (MTX) is an antimetabolite with a major role in the treatment of acute lymphoblastic leukaemia (ALL). The authors report the management of a 9-year-old boy who developed an anaphylactoid reaction to high-dose MTX infusion, after a first challenge with intrathecal administration, during induction therapy for ALL. A desensitization protocol was followed and MTX tolerance has been successfully achieved, allowing this patient to complete the needed chemotherapy.

Acral erythema caused by high-dose methotrexate therapy in patients with osteogenic sarcoma

High doses of methotrexate (MTX) have been incorporated in the treatment of osteogenic sarcoma since the 1970s. Unfortunately, high-dose MTX (HD-MTX) can cause untoward side effects that may complicate the proper management of these patients. Two cases of MTX-induced acral erythema are described and the possible implications of this complication are reviewed, with a discussion of the pathophysiology of this adverse effect. Two young female patients suffering from osteogenic sarcoma received HD-MTX (12 g/m2) according to the chemotherapeutic protocol. A 17-year-old patient with osteogenic sarcoma of the head developed painful acral erythema of her palms and soles after the fifth dose of MTX, and a 22-year-old patient with osteosarcoma of the femur developed severe acral erythema after the sixth dose. The severity of the reaction was significant enough to cancel further treatment with HD-MTX in both patients. All symptoms resolved without sequellae several weeks later in both cases. Acral erythema may pose a significant albeit transient phenomenon adversely influencing chemotherapy in patients suffering from osteosarcoma and treated with HD-MTX. The pathophysiology of this side effect is not completely understood and further investigation of the pharmacokinetics of HD-MTX in this patient population is needed.

A Rare Drug Reaction to Methotrexate After Treatment for Ectopic Pregnancy

BACKGROUND

Ectopic pregnancies are commonly diagnosed and treated in physicians' offices. In the hemodynamically stable patient, therapy often includes treatment with methotrexate. Well-known adverse effects of this drug include mucositis, abdominal cramping, and malaise. We report a case of a rare drug reaction after treatment with methotrexate.

CASE

A 34-year-old, gravida 2, para 0, at 7 weeks of gestation by last menstrual period was diagnosed with an ectopic pregnancy and treated with methotrexate. The patient had an anaphylactoid reaction shortly after administration of methotrexate.

CONCLUSION

Methotrexate is a commonly used therapy for ectopic pregnancies in the outpatient setting. Practitioners should be aware of the potential adverse reactions to methotrexate.

Management of an anaphylactoid reaction to methotrexate with a stepwise graded challenge

We report the management of a 15-year-old boy with an anaphylactic or anaphylactoid response to his first dose of methotrexate during induction therapy for acute lymphoblastic leukemia (ALL). Because weekly methotrexate therapy is an important component of continuation chemotherapy for pediatric ALL, a stepwise graded challenge was employed to achieve drug tolerance.