Long-term renal follow-up of children treated with cisplatin, carboplatin, or ifosfamide: a pilot study.

BACKGROUND

Childhood cancer survivors treated with cisplatin, ifosfamide, or carboplatin are at risk for late kidney and blood pressure (BP) abnormalities. Few studies have comprehensively evaluated kidney outcomes and 24-h ambulatory BP monitoring (ABPM) in this population. We aimed to describe chemotherapy-associated acute kidney injury (AKI) and late kidney outcomes using standardized definitions.

METHODS

This was a single-center longitudinal pilot study of 23 children who participated in a previous study during cisplatin, carboplatin, or ifosfamide treatment. Medical charts were reviewed retrospectively. Available patients were approached for a study visit for blood and urine collection, BP measurement, and ABPM. AKI is defined by serum creatinine (SCr) rise (Kidney Disease: Improving Global Outcomes definition [SCr-AKI]). Electrolyte-AKI is defined by hypokalemia, hypophosphatemia, or hypomagnesemia. Chronic kidney disease (CKD) is defined by estimated glomerular filtration rate < 90 mL/min/1.73 m2, albuminuria, or proteinuria. Electrolyte-CKD is defined by low serum electrolyte concentration or electrolyte supplementation.

RESULTS

Median age at chemotherapy start was 8.3 years; 9/23 (39%) were boys. Fourteen out of 23 (61%) patients had SCr-AKI during therapy; all developed electrolyte-AKI. Median 5.7 years post-chemotherapy, 7/22 (32%) had CKD, 11/23 (48%) had electrolyte-CKD, and 2/20 (10%) had hypertension. Fifteen out of 23 patients (65%) had either CKD, electrolyte-CKD, or hypertension. In ten patients available for a study visit (median 4.9 years post-chemotherapy), 1/10 (10%) had hypertension by ABPM; none had masked or white coat hypertension. All ten had at least one kidney abnormality (CKD, electrolyte-CKD, office pre-hypertension, or abnormal ABPM).

CONCLUSIONS

Using standardized outcome definitions, children treated with cisplatin, carboplatin, or ifosfamide have a high prevalence of late kidney abnormalities. Research must elucidate best practice for post-cancer treatment follow-up and kidney complication treatment.