Aim
To describe an unusual presentation of autoimmune adrenal insufficiency
Methods
Case report.
Results
An 8 year old presented to the ED with kussmaul breathing, fevers and vomiting. He was a previously well child, and had a significant family history for maternal T1D. An initial diagnosis of SARS-CoV-2 infection was made, however blood gas demonstrated hyperglycaemia, ketosis, a high anion gap metabolic acidosis and moderate-severe hyponatraemia consistent with severe DKA.
The patient was given a preliminary bolus of 10ml/kg of 0.9% saline, with subsequent intravenous fluids of 150ml/hour (calculated as maintenance and 7.5% dehydration replacement over 48 hours). As per protocol he was also commenced on an insulin infusion.
Over the following 48 hours his hyperglycaemia and acidosis corrected and he was transitioned to subcutaneous insulin. Subsequently, his hyponatraemia, which had almost normalised, began to worsen and measurement of urine sodium suggested renal loss of sodium.
Further investigations revealed an elevated renin and low aldosterone with normal ACTH and cortisol. Adrenal antibodies titres were significantly elevated. He was commenced on mineralocorticoid replacement and diagnosed with an early presentation of autoimmune adrenal insufficiency (ADI). Table 1 summarises his clinical course and investigations.
ADI is characterised by development of anti-adrenal or 21-hydroxylase antibodies directed against the adrenal cortex. It has been associated with autoimmune polyglandular syndrome (APS) and in our patient, a diagnosis of APS 2 has been made.
ADI demonstrates a classic natural history of 5 stages, in which there is progressively increasing adrenal dysfunction (Figure) (1). Our patient was diagnosed as likely being in Stage 1 ADI, with multiple risk factors to continue progression including male gender and a diagnosis of APS 2 (2).
Conclusion
This case demonstrates the importance of considering other cause of electrolyte disturbance in patients with DKA.