ENDOCRINOLOGY

 

Adrenal Insufficiency

Hx: (1º) n/v, diarrhea, fatigue, hypotension/syncope, hyperpigmentation, hypoNa, hyperK; (2º)  -

Etiology: Causes: autoimmune, infectious (Tb, histoplasmosis, ;  in (in HIV): CMV, MAI), Waterhouse-Friderichsen, cancer (breast, lung, lymphoma), drugs (ketoconazole)

Dx: - Studies: AM cortisol: <5 insufficient, 5-18 indeterminant, >18 sufficient

If indeterminant --> Low dose cosyntropin stimulation test.  Check baseline & 30 min cortisol level after administering cosyntropin 1 mcg IV.  A cortisol value of > 18 mcg/dLl pre-stim or after 30 min rules-out adrenal insufficiency (sensitivity 95%, specificity 96%).

 

- Relative adrenal insufficiency in sepsis --:  High dose cosyntropin stimulation. Check baseline, 30 min & 60 min cortisol level after administering co, co-syntropin 250mcg IV. Relative insufficiency ≤ 9 mcg/dl increase at either 30 or 60 min.  Rx: hydrocortisone 100mg IV q6hrs & fludrocortisone 50mcg IV qd x 7d. [JAMA (2002) 228: 862 – 71]

 

Diabetic Ketoacidosis

 Hx: delta MS, n/v, abd pain, polyuria, polydipsia, dehydration, ketotic breath, tachycardia, hypotension

Etiology: infection, medicine non-compliance, CVA, MI, severe illness, surgery, pregnancy

Dx: hyperglycemia >300mg/dl, anion gap metabolic acidosis, hypo-PO4, hypo-Mg, pseudohyponatremia, hypo-K or hyper-K, pre-renal ARF, hemoconcentration, elev WBCs.

Rx: replete fluid, lytes, insulin and follow closely. Use NS at rate>125cc/hr, change to D5 NS when dexi<250. Give insulin 10units IV stat, then 0.1-0.2U/kg/hr and titrate to AG and dexis. Glucose should decrease 80/hr. Keep insulin drip going until gap is closed and bicarb is >18. Give SC insulin with closed gap and turn off insulin drip one hour later. Follow dexi q1hr, BMP/Mg/PO4 q2-4hr. Replete K, Mg, PO4. Only use IV bicarbonate if pH<7.0 or severe hyperkalemia. Monitor for arrhythmias, shock, hypoglycemia.