Addison's disease presenting as isolated mineralocorticoid deficiency in a child with type 1 diabetes mellitus

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 1-16-Adrenal Insufficiency
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-14
Amit Lahoti*, Jason Klein, Phyllis W Speiser, Graeme R Frank and Paula M Kreitzer
Cohen Children's Medical Center of NY/North Shore LIJ Health System, Lake Success, NY
Background:

Type 1 diabetes mellitus (T1DM) is associated with several other autoimmune conditions. Autoimmune primary adrenal insufficiency (Addison’s disease, AD) occurs in ~0.5% of patients, and usually presents with combined glucocorticoid (GC) and mineralocorticoid (MC) deficiency. Isolated MC deficiency is rare as the presenting feature.

Case report:

A 7.8 year old Caucasian boy with T1DM of 3 years duration presented with 1 day of vomiting, abdominal pain and decreased urination; he had no diarrhea or fever. His HbA1c had been 8.1% - 8.6% on basal-bolus insulin therapy and no other medications. There was no history of hypoglycemia and no family history of autoimmune disease.

On examination: Pulse: 128/minute, BP: 98/68 mmHg. He appeared 5-10 % dehydrated. Height SDS: -0.68, weight SDS: -1.31. Initial lab results (all serum electrolytes in mmol/l; Glu & BUN/ Creatinine in mg/dl):

Glucose: 205, Na: 121(corrected Na: 123), K: 6.8, Cl: 80, Bicarb: 15, BUN/Cr: 43/0.78. Random cortisol was 26.5 µg/dl. He received a 10 ml/kg normal saline (NS) bolus followed by NS hydration at 1.5 times maintenance. Serum potassium ranged from 4-5.2; serum sodium improved gradually to 134 prior to discharge.

He returned to the ED several hours after discharge with vomiting, worsening abdominal pain and fever. Readmission tests showed:

Glucose: 133, Na 130, K 4.7, Cl 98, Bicarb 15, BUN/Cr: 9/0.4

Patient again received NS hydration. His serum sodium remained in the low 130’s. He was started on a proton-pump inhibitor with relief of abdominal pain. Oral intake improved and he was discharged on day 5 with normal electrolytes.

Lab tests done 2 days after hospital discharge showed:  normal serum Na (137 meq/L) with inappropriately elevated urine Na at >250 meq/L and a markedly elevated plasma renin activity (PRA) of 36.8 ng/ml/hr (0.5-5.9) with unmeasurably low serum aldosterone of <1 ng/dl (5-80). The following additional results were obtained 2 days later:

Cortisol 8 AM: 17.7 ug/dl, ACTH: 198 pg/mL (H, 6-48)

PRA: 68.2 ng/ml/hr (H), Serum Aldosterone: <1 ng/dL (L)

21-hydroxylase antibodies: 1790 U/L (H, <1)

Hence, a diagnosis of AD presenting as isolated MC deficiency was made. He was started on fludrocortisone 0.1 mg PO daily and low dose hydrocortisone with resolution of symptoms and metabolic abnormalities

Conclusions:

Addison disease should be suspected in patients with T1DM who have unexplained fatigue, abdominal pain, weight loss, poor growth, or electrolyte perturbations (hyponatremia and/or hyperkalemia), even with normal cortisol levels. Mineralocorticoid deficiency can be the sole presenting feature of Addison disease.

Nothing to Disclose: AL, JK, PWS, GRF, PMK

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