Pharmacologic probing of amphotericin B-induced renal dysfunction in the neonatal rat

Amphotericin B in Pediatrics: Analysis by Age Stratification Suggests a Greater Chance of Adverse Events from 13 Months of Age Onwards

BACKGROUND AND OBJECTIVE

Amphotericin B deoxycholate (AMB-D) remains an antifungal agent with great therapeutic value in pediatric patients. The currrent consensus is that its use in neonates is safer than in older children. However, childhood presents different periods of development that deserve to be evaluated more precisely. Our goal was to assess the usage profile of AMB-D in stratified pediatric age groups, adapted according to the National Institute of Child Health and Human Development classification.

METHODS

This retrospective cross-sectional observational study was conducted at a Brazilian tertiary children's hospital between January 2014 and December 2019.  Data of patients who received at least two doses of intravenous AMB-D while hospitalized were extracted from electronic health files. Information on patient demographics, underlying diseases and comorbidities, laboratory examinations, fungal infection diagnosis, and AMB-D use were gathered following specific criteria. Nonparametric tests were applied, such as the chi-square test to compare proportions and Fisher's exact test to assess the association between categorical variables or contingency tables.

RESULTS

One hundred and twenty-seven (127) medical records were stratified as preterm neonatal (birth <37 weeks postmenstrual age), term neonatal (birth-27 days), infants (28 days-12 months), toddlers (13 months-2 years), early childhood (3-5 years), middle childhood (6-11 years), and early adolescence (12-18 years). The criteria for the indication of AMB-D followed empirical use as the main indication (n = 74; 58.26%), proven and probable fungal infection (n = 39; 30.71%), and medical suspicion (n = 14; 11.02%). Candida spp. was the main etiologic agent isolated in cultures, with the highest frequency of C. albicans (n = 18; 40%), followed by Candida parapsilosis (n = 14; 31.11%), and Candida tropicalis (n = 6; 13.33%). Very few acute infusion-related adverse effects were observed during the administration of AMB-D in pediatric patients. We found an unfavorable impact of AMB-D use in patients from 13 months of age onwards suggesting this group as a turning point for a greater chance of adverse events, and not soon after the neonatal period.

CONCLUSIONS

Clinical or observational studies based on age stratification are essential to accurately elucidate whether potentially toxic drugs can be used safely in the pediatric population. Our search for a turning point was shown to contribute to the accuracy of the study, as it provided data on the impact of D-AMB in specific pediatric age groups.

The influence of Myrj 59 on the solubility, toxicity and activity of amphotericin B

The effect of Myrj 59 (a polyoxyethyleneglycol derivative of stearic acid) on amphotericin B (Am B) solubility, toxicity and activity has been investigated. We showed that Myrj 59 could solubilize the antibiotic. Moreover, it also decreased and abolished the haemolytic activity of the drug by increasing the resistance of the red blood cells and impairing the interaction of Am B with the cellular membrane cholesterol, but it did not modify the in-vitro antifungal activity of the drug. On the other hand, Myrj 59 did not decrease the acute in-vivo toxicity of the drug (LD50 and nephrotoxicity). In a previous study we have shown that a polyoxyethleneglycol derivative of cholesterol could solubilize Am B and was able to decrease the in-vitro and in-vivo toxicity of the antibiotic without altering its in-vitro antifungal activity. The results of the present study suggest that the cholesterol moiety of the surfactant is not necessary to decrease the in-vitro lytic activity of the drug but could play a role in the reduction of the in-vivo toxicity.