Hypoglycemia Associated With PEG-asparaginase and 6-MP Therapy During Treatment of Acute Lymphoblastic Leukemia in Pediatric Patients: A Case Series.

BACKGROUND: Asparaginases are a mainstay treatment for pediatric acute lymphoblastic leukemia (ALL). Recent reports identified hypoglycemia associated with asparaginases. Other reports describe hypoglycemia associated with 6-mercaptopurine (6-MP), another fundamental ALL therapy. Little is known about the risk of hypoglycemia associated with ALL therapy, an adverse event that puts children at risk of decreased level of consciousness, seizures, and possibly negative neurocognitive sequelae. METHODS: We performed a retrospective chart review of 6 children with hypoglycemia during ALL treatment in our institution from May 2016 to August 2019. Timing and duration of hypoglycemia relative to polyethylene glycol (PEG)-asparaginase, 6-MP, and corticosteroids were determined. Laboratory values of the critical sample were collected. RESULTS: The median age was 2.75 (interquartile range: 1.88 to 3.63) years. Three patients had trisomy 21. The onset of hypoglycemia was 5 to 19 days after the most recent PEG-asparaginase administration or 6 to 7 months after initiating daily 6-MP. Sixteen hypoglycemic events were documented, and 9/16 had a critical sample drawn. Six events were hypoketotic, associated with PEG-asparaginase. Three were ketotic, associated with 6-MP. Two patients required treatment with diazoxide and cornstarch. CONCLUSIONS: Hypoglycemia associated with PEG-asparaginase occurred later and lasted longer than previous reports with l-asparaginase, with the likely mechanism being hyperinsulinism. 6-MP was associated with ketotic hypoglycemia.

Spatial distribution patterns of tick community structure in sympatric jaguars (Panthera onca) and pumas (Puma concolor) from three ecoregions in Mexico.

We examined tick communities on wild felid hosts in three ecoregions of Mexico. We collected 186 ticks of 7 species from 10 pumas (Puma concolor) and 9 jaguars (Panthera onca). Tick community composition varied across the ecoregions, and across host species within each region. Overall, Ixodes affinis, Amblyomma ovale, and Amblyomma tenellum were the most abundant species; however, only the latter two ticks were distributed across all three ecoregions, while I. affinis, along with Ixodes spinipalpis, Amblyomma inornatum, and Amblyomma parvum were restricted to more limited geographical regions. Ixodes affinis occurred strictly in southern tropical rainforest ecoregions and was significantly more abundant in Selva Lacandona compared with the Yucatán Peninsula. Amblyomma ovale was significantly more common in the tropical dry forest in the Pacific coastal ecoregion. Amblyomma tenellum abundance tended to be higher on jaguars, while I. affinis abundance was higher on pumas. Regional distribution patterns of some tick species (e.g., I. affinis and I. spinipalpis) may be determined by off-host environmental conditions rather than host factors. In contrast, at the local scale, occurrence and abundance of some tick species (e.g., A. tenellum, A. ovale and Rhipicephalus microplus) might be driven by ecological-host factors, such as habitat use or predator-prey relationships.

Cardiac Magnetic Resonance Imaging in Pediatric Turner Syndrome.

OBJECTIVE: To compare the detection of cardiac lesions with the use of cardiac magnetic resonance imaging (CMR) and conventional echocardiography in children with Turner syndrome. STUDY DESIGN: Twenty-four girls with Turner syndrome, 8-18 years of age, were recruited through the Pediatric Endocrinology Program. Participants underwent CMR and echocardiography within a 2-year period, and discrepancies between the results of each modality were identified. RESULTS: Fifteen of 24 (63%) girls had a cardiac lesion identified on CMR or echocardiography. Both modalities identified the same lesion in 10 of 15 (67%); however, 6 of 15 (40%) participants had a lesion identified on CMR but not echocardiography. Participants with a missed lesion had a trend towards greater body mass index. Aortic dilation and bicuspid aortic valve were the most commonly missed lesions by echocardiography. CONCLUSIONS: CMR identifies significant cardiac lesions missed by echocardiography in pediatric patients with Turner syndrome, particularly along the aorta. These findings support the current guidelines that recommend screening CMR in addition to echocardiogram. Early identification of cardiac abnormalities in patients with Turner syndrome will allow for a greater understanding of the natural history in these patients and potentially identify candidates for earlier intervention.