High-dose methotrexate-associated acute renal failure may be an avoidable complication

Identification of Risk Factors in High-Dose Methotrexate-Induced Acute Kidney Injury in Childhood Acute Lymphoblastic Leukemia

AIMS

Although high-dose methotrexate (HDMTX) is an effective means for the treatment of acute lymphoblastic leukemia (ALL), the development of renal dysfunction remains a significant management challenge. This study aimed to identify the key factors in HDMTX-induced acute kidney injury (AKI) in childhood ALL.

METHODS

We retrospectively analyzed the clinical data in 1,329 courses of HDMTX treatment in 336 Chinese ALL children at the First Affiliated Hospital of Guangxi Medical University from September 2012 to November 2016. The clinical data were compared between the groups of children with development of AKI and those without. Risk factors were identified by multiple logistic regression analysis, and the diagnostic performance of plasma MTX concentration was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

AKI was observed in 88 patients (26.2%) and 104 courses (7.8%). Binary logistic regression revealed that age (OR 1.349; p = 0.005), first HDMTX course (OR 1.767; p = 0.013), MTX dose per body surface area (BSA; OR 1.944; p = 0.015), and baseline serum total protein (OR 0.929; p = 0.021) significantly correlated with AKI. The area under the ROC for 48-h plasma MTX concentration was 0.890 (95% CI 0.850-0.930), and sensitivity and specificity values of the cut-off value were 78.8 and 90.4%, respectively.

CONCLUSION

Increasing age, higher MTX dose per BSA, lower baseline serum protein, and first HDMTX course were significant risk factors for developing HDMTX-induced AKI in childhood ALL. The threshold of 48-h MTX plasma concentration is valuable for the prediction of HDMTX-induced AKI.

Intravenous radiographic contrast administered prior to high-dose methotrexate and subsequent toxicity requiring the use of glucarpidase

Methotrexate is a dihydrofolate reductase inhibitor that interferes with DNA synthesis, DNA repair, and cellular replication. We present the first adult case of a patient who received intravenous contrast prior to administration of high-dose methotrexate, who subsequently experienced delayed methotrexate clearance and renal impairment necessitating the use of glucarpidase. This case displays a possible correlation between intravenous radiographic contrast administration and resulting toxicity due to delayed methotrexate clearance.

Drug repositioning in the treatment of malaria and TB

The emergence and spread of drug resistance in the malaria parasite Plasmodium falciparum as well as multi- and extremely drug-resistant forms of Mycobacterium tuberculosis, the causative agent of TB, could hamper the control of these diseases. For instance, there are indications that the malaria parasite is becoming resistant to artemisinin derivatives, drugs that form the backbone of antimalarial combination therapy. Likewise, Mycobacterium tuberculosis strains that are multidrug-resistant or extremely drug-resistant to first- and second-line drugs have been associated with increased mortality. Thus, more than ever, new antimalarials and anti-TB drugs are needed. One of the strategies to discover new drugs is to reposition or repurpose existing drugs, thus reducing the cost and time of drug development. In this review, we discuss how this concept has been used in the past to discover antimalarial and anti-TB drugs, and summarize strategies that can lead to the discovery and development of new drugs.

Retrospective study on elimination delay of methotrexate in high-dose therapy of childhood acute lymphoblastic leukemia in China

OBJECTIVES

The aim of this study was to observe the morbidity of elimination delay in Chinese children with acute lymphoblastic leukemia during high-dose methotrexate (HDMTX) therapy and the toxicities.

PATIENTS AND METHODS

A total of 121 children with acute lymphoblastic leukemia on HDMTX therapy were enrolled into this study. Patients were divided into groups on the basis of either dosage (3 g/m vs. 5 g/m) or infusion duration (7 h vs. 24 h). CF/MTX index was used to determine the calcium folinate (CF) rescuing intensity and toxicity was evaluated according to World Health Organization criteria.

RESULTS

The overall morbidity of elimination delay was 12.1% in a total of 497 infusions. Patients with elimination delay had lower platelet count (P<0.01) and greater cumulative CF rescuing intensity (P<0.001). In 3-g group, children with elimination delay experienced severer oral mucous membrane damage (P<0.05) than those without elimination delay, and postponement of following chemotherapy (P=0.001). No significant difference was found in morbidity of elimination delay between 3 and 5-g groups (P>0.05) or 7 and 24-hour infusion groups (P>0.05). The only raised adverse effect in 5-g group was gastrointestinal (P=0.003) as compared with 3-g group. The CF rescuing intensity of 5-g group without elimination delay was lower than that of the 3-g group (P<0.01).

CONCLUSIONS

(1) HDMTX with 5 g/m is as safe as 3 g/m under adequate hydration and alkalization. Twenty-four-hour infusion is optimal. (2) Individualized dosing is necessary.

Severe methotrexate toxicity precipitated by intravenous radiographic contrast

Methotrexate (MTX), a widely used anticancer agent, and intravenous iodinated contrast used for radiographic studies can both cause acute renal failure. Their combined exposure may place patients at higher risk for renal failure. This report describes 2 pediatric patients with MTX toxicity precipitated by the use of intravenous radiographic contrast. One patient recovered with leucovorin rescue therapy, whereas the second patient responded to carboxypeptidase-G2. Both patients suffered MTX-related toxicities including myelosuppression and mucositis, but recovered full renal function and tolerated further high-dose MTX therapy. These cases suggest that intravenous iodinated contrast should be avoided in patients receiving high-dose MTX.