Acute Methotrexate Toxicity Due to Overdosing in Psoriasis: A Series of Seven Cases

A Case of Severe Organ Dysfunction and Skin Lesions Due to Methotrexate Toxicity

Methotrexate is an anti-inflammatory and immunomodulatory drug, widely used for moderate to severe psoriasis and other rheumatological conditions such as rheumatoid arthritis, besides some types of malignancies. Side effects are more prevalent in high acute doses but can also be seen in low-dose chronic use, especially in cases of drug-dosing errors. Possible symptoms of toxicity include gastrointestinal, hepatic, hematologic and renal dysfunctions, but may also include mucositis and worsening of the psoriatic lesions. Here, we describe a case involving methotrexate toxicity in an elderly patient with psoriasis, detailing the management.

Acute methotrexate toxicity in a patient with psoriasis: a case report

Aside from rheumatoid arthritis, methotrexate is also used to treat cancer, psoriasis, and other diseases. Side effects with methotrexate are possible, as they are with any medication. This drug is extremely potent and has the potential to produce serious adverse effects. Those who use this medication need to be tracked often. We provide a case of a patient with psoriasis vulgaris who died due to methotrexate administration without proper dosage verification. A female patient in her forties had a history of psoriasis vulgaris of the lower limbs. Under treatment, she developed acute methotrexate toxicity. This drug was taken as an intramuscular injection per day in an infirmary without checking that the dose regimen prescribed was per week. She developed extensive bullous and pustular lesions associated with digestive signs related to generalized toxiderma. But at that point, she had septic shock, which led to her death a few weeks after the methotrexate injection. The medical responsibilities of the doctor, pharmacist, and nurse were discussed. To conclude, methotrexate is not a killer drug in most cases, but it can be extremely harmful if it's overused. Acute toxicity is a potentially fatal condition, and a deeper understanding of its potential toxicity is still necessary.

Impact of European Union label changes to avoid inadvertent use of medicinal products containing methotrexate for once-weekly administration: A survey amongst prescribers, pharmacists and patients on awareness, knowledge, and behaviour

PURPOSE

To determine the effectiveness of risk minimisation measures (RMM) to avoid inadvertent daily instead of weekly methotrexate (MTX) use, introduced by the European Medicines Agency (EMA) from 2019 onwards.

METHODS

Using a cross-sectional online survey in France, Greece, Germany, Poland, and Sweden in 2022, we assessed awareness, knowledge, and self-declared behaviour for respondents who prescribed, dispensed, or used once-weekly MTX in the last 3 months. Respondents' answers were considered as 'successful' with regards to RMM effectiveness (vs. unsuccessful) if they provided correct ('desirable') responses to 100% of questions regarding awareness and self-declared behaviour and correct responses to ≥80% of questions about knowledge. Per target population, an outcome was considered successful if achieved by ≥80% of respondents. Effectiveness of RMM was defined by ≥80% being successful on all outcomes.

RESULTS

One-hundred-fifty-one prescribers, 150 pharmacists, and 150 patients completed the survey. Success rates were 56% (95% CI 48.0%-64.3%) for awareness, 42% (95% CI 34.4%-50.7%) for knowledge, and 31% (95% CI 23.8%-39.2%) for self-declared behaviour among prescribers, 18% (95% CI 12.8%-25.8%) for awareness, 7% (95% CI 3.7%-12.7%) for knowledge, and 50% (95% CI 41.7%-58.3%) for self-declared behaviour among pharmacists, and 29% (95% CI 21.6%-36.6%) for awareness, and 3% (95% CI 1.1%-7.6%) for knowledge among patients. Overall success was not attained by any target population.

CONCLUSIONS

RMM were evaluated as not effective across outcomes of awareness, knowledge, and self-declared behaviour in prescribers, pharmacists, and patients. Findings suggested we need continued efforts for RMM across all target populations and across all outcomes.

Consensus on the therapeutic management of atopic dermatitis ‒ Brazilian Society of Dermatology: an update on phototherapy and systemic therapy using e-Delphi technique

This publication is an update of the "Consensus on the therapeutic management of atopic dermatitis - Brazilian Society of Dermatology" published in 2019, considering the novel, targeted-oriented systemic therapies for atopic dermatitis. The initial recommendations of the current consensus for systemic treatment of patients with atopic dermatitis were based on a recent review of scientific published data and a consensus was reached after voting. The Brazilian Society of Dermatology invited 31 experts from all regions of Brazil and 2 international experts on atopic dermatitis who fully contributed to the process. The methods included an e-Delphi study to avoid bias, a literature search and a final consensus meeting. The authors added novel approved drugs in Brazil and the indication for phototherapy and systemic therapy for AD. The therapeutical response to systemic treatment is hereby reported in a suitable form for clinical practice and is also part of this updated manuscript.

Comparison of two doses of leucovorin in severe low-dose methotrexate toxicity - a randomized controlled trial

BACKGROUND

Leucovorin (folinic acid) is a commonly used antidote for severe toxicity with low-dose methotrexate, but its optimum dose is unclear, varying from 15 to 25 mg every 6-h.

METHODS

Open-label RCT included patients with severe low-dose (≤ 50 mg/week) methotrexate toxicity defined as WBC ≤ 2 × 10^9/L or platelet ≤ 50 × 10^9/L and randomized them to receive either usual (15 mg) or high-dose (25 mg) intravenous leucovorin given every 6-h. Primary outcome was mortality at 30-days and secondary outcomes were hematological recovery and mucositis recovery.

TRIAL REGISTRATION NUMBER

CTRI/2019/09/021152.

RESULTS

Thirty-eight patients were included, most with underlying RA who had inadvertently overdosed MTX (taken daily instead of weekly). At randomization, the median white blood and platelet count were 0.8 × 10^9/L and 23.5 × 10^9/L. 19 patients each were randomized to receive either usual or high-dose leucovorin. Number (%) of deaths over 30-days was 8 (42) and 9 (47) in usual and high-dose leucovorin groups (Odds ratio 1.2, 95% CI 0.3 to 4.5, p = 0.74). On Kaplan-Meier, there was no significant difference in survival between the groups (hazard ratio 1.1, 95% CI 0.4 to 2.9, p = 0.84). On multivariable cox-regression, serum albumin was the only predictor of survival (hazard ratio 0.3, 95% CI 0.1 to 0.9, p = 0.02). There was no significant difference in hematological or mucositis recovery between the two groups.

CONCLUSION

There was no significant difference in survival or time-to hematological recovery between the two doses of leucovorin. Severe low-dose methotrexate toxicity carried a significant mortality.

Overview of Methotrexate Toxicity: A Comprehensive Literature Review

Methotrexate (MTX) is significantly more effective than and has a considerable advantage over placebo in patients with severe and persistent rheumatoid arthritis (RA). The drug is used to treat a variety of malignant disorders (leukemia and cancer of the lung, breast, and uterus) and ectopic pregnancy. As its side effects are outweighed by its effectiveness, MTX is a first-line antirheumatic drug in many countries. MTX is found in extracellular compartments, such as the synovium, as well as other organs, such as the kidney and liver. To improve treatment, increase adherence, and decrease mortality in MTX therapy, it is essential to reduce its toxicity and understand its side effects. Therefore, this comprehensive review was conducted to assist physicians and researchers in better understanding the toxicity of MTX and how to deal with this toxicity. MTX is eliminated via the kidneys, which are capable of excretion and reabsorption within the renal tubules. Although higher doses of MTX (known as high-dose MTX (HD-MTX), defined as doses of 500 mg/m² or greater) are often more beneficial, they can produce toxicity and side effects such as bone marrow suppression, pulmonary toxicity, nephrotoxicity, hematologic toxicity, and an increased risk of infections. Treatment of severe MTX toxicity has three main goals: clearance of MTX from the bloodstream, folinic acid therapy, and organ treatment. Leucovorin is highly beneficial in preventing myelosuppression, gastric toxicity, and neurotoxic effects after HD-MTX therapy. The preferred antidote for MTX poisoning is folinic acid. Glucarpidase has been licensed for the treatment of high plasma MTX levels of >1 μmol/L in patients with compromised renal function who have delayed MTX elimination. In patients with renal deficiency, a lower initial dose is considered with an estimated glomerular filtration rate (eGFR) between 30 and 59 mL/minute. These patients need to be monitored, and a more gradual dosage increase and a lower weekly maximum should be considered regarding their general health situation. MTX is contraindicated in patients with RA if the eGFR is <30 mL/minute.