Diagnosis of DIDM during ALL directed chemotherapy
Diagnostic criteria used in literature for DIDM /hyperglycemia varies
significantly with cut offs used, timing of test, number of abnormal
tests used for diagnosis(20)(15)(21)(22). However, as per the most
recent pediatric diabetes guidelines, diagnosis of DIDM is not different
from Diabetes mellitus (DM) due to any other etiology (23)(24).
Nevertheless, these criteria should be carefully applied considering the
pharmacology of the offending drug, pathogenesis of DIDM and taking into
account of its transient nature.
Measurement of fasting glucose alone will underestimate the incidence of
DIDM when on intermediate acting glucocorticoids (prednisolone, methyl
prednisolone) as a single morning dose considering their peak (4-6
hours) action and duration of action (12-16 hours). In such instances,
measuring post lunch and/or pre dinner blood sugar values would be
useful. When long acting glucocorticoids (Dexamethasone) or
intermediate-acting glucocorticoids in divided doses are used
post-lunch, pre-dinner and fasting glucose values would be helpful for
diagnosis. Utility of oral glucose tolerance testing is limited in
diagnosing DIDM during ALL treatment due to practical difficulty in
conducting the test. Similarly, HbA1c is also not useful considering the
acute onset of DIDM(25)(26). Hence post-lunch and/or pre-dinner glucose
level ≥ 200 mg/dl, when on intermediate-acting glucocorticoids as single
morning dose and additional fasting glucose ≥ 126 mg/dl when on
long-acting steroids or intermediate acting steroids in divided doses
are most useful for diagnosing glucocorticoid induced Diabetes Mellitus.
For L-asparaginase induced Diabetes mellitus, random sugar value of ≥200
mg/dl, can be used for diagnosing DIDM as there is no fixed pattern of
hyperglycemia seen. It is imperative to confirm the diagnosis by repeat
testing in the absence of unequivocal hyperglycemia(23)(24).