Introduction: Methotrexate (MTx) is widely used in high doses in a variety of cancers. Dosing is followed by leucovorin, alkalinization and hydration to avoid toxicity which still occurs in 1.8% ¹ of cases. Haemodialysis (RRT) has been used to rapidly reduce the level of MTx.

Cases Summary

Patient A: 60 yo man with past medical history (PMHx) of stage 3 diffuse large B-cell lymphoma was admitted for chemotherapy (Cycle 3 day 6 of Rituxan + MTx + Cytarabine). His admission creatinine was 0.72 mg/dl. He received MTX 900mg over 15 minutes then 5500 mg over 3 hours. On day 3 of receiving MTx patient’s creatinine increased to 1.83 mg/dl with oligouira and MTx level of 44 μmol. Patient had one session of haemodialysis immediately after the peak level of MTX of 44 μmol. MTx level came down to 0.14 μmol without requiring further haemodialysis sessions. Creatinine remained stable between 1.3- 1.6 mg/dl with good urine output. Renal function stabilized at 0.8 mg/dL with MTx level of 0.08μmol.

Patient B: 55 yo AAM with PMHx of hepatitis C, bipolar disorder and active heroin/cocaine abuse was diagnosed with T- cell acute lymphoblastic lymphoma. He received four doses of MTx (6,000 mg). Over the next 3 days, creatinine worsened from 0.77 > 1.38 > 3.25 > 4.16 mg/dl in the setting of elevated MTX level. Patient received IVF, urinary alkalinization and maximum dose leucovorin. Patient developed oliguric and volume overload. With concern for extra- renal toxicity he was initiated on CVVHD. He remained on RRT for 17 days despite receiving glucarpidase.

Discussion: Early RRT in MTx toxicity is effective in reducing the duration of acute kidney injury and has better patient outcome with less resources required. 

This study examined the incidence of white-coat hypertension (WCH) and masked hypertension (MHT) in the pediatric population with varying body mass index at our tertiary specialty clinic. We analyzed 174 patients that were referred to our center for the evaluation of hypertension. All of these patients were evaluated with 24-hour ambulatory blood pressure monitor (ABPM). We also obtained their body mass index (BMI), family history, gender, age, and ethnicity. The study showed that patients with a high BMI have a higher incidence of white coat hypertension. Of The patients with a BMI of greater than 30, 69% had WCH, of patients with a BMI from 25 to 30, 59% had WCH and of patients with a BMI of less than 25, 41% had WCH.  In contrast, masked hypertension was observed more frequently in lean patients; 20% of patients with MHT had a BMI of less than 25, 17% of patients with MHT had a BMI of 25 to 30 and 5% of patients with MHT had a BMI of more than 30.

In conclusion, ABPM is an effective tool to evaluate the white coat hypertension in obese and overweight children. As BMI increases, the incidence of WCH also increases. Given these results, we emphasize the importance of ambulatory blood pressure monitoring in the management of pediatric hypertension with overweight and obese patients.