A 67-year-old Caucasian woman was brought to the clinic by her son who stated that his mother had become slightly
confused over the past several days.
... [Show More] She had been stumbling at home and had fallen once but was able to ambulate
with some difficulty. She had no other obvious problems and had been eating and drinking. The son became
concerned when she forgot her son’s name, so he thought he better bring her to the clinic.
PMH-Type II diabetes mellitus (DM) with peripheral neuropathy x 20 years. COPD. Depression after death of
spouse several months ago
Social/family hx - non contributary except for 30 pack/year history tobacco use.
Meds: Metformin 500 mg po BID, ASA 81 mg po qam, escitalopram (Lexapro) 5 mg po q am started 2 months ago
Labs-CBC WNL; Chem 7- Glucose-92 mg/dl, BUN 18 mg/dl, Creatinine 1.1 mg/dl, Na+120 mmol/L,
K+4.2 mmol/L, CO237 m mol/L, Cl-97 mmol/L.
The APRN refers the patient to the ED and called endocrinology for a consult for diagnosis and management of
syndrome of inappropriate antidiuretic hormone (SIADH).
QUESTION:
Define SIADH and identify any patient characteristics that may have contributed to the
development of SIADH.
ANSWER:
SIADH is the syndrome of inappropriate antidiuretic diuretic hormone secretion. ADH, normally
would cause an increase in water reabsorption, increasing intravascular volume and diluting
serum sodium. In SIADH, ADH is secreted to a point of causing hyponatremia from an over
secretion of ADH. This can be caused by intracranial issues, paraneoplastic syndrome,
pulmonary disease, drug toxicity, autoimmune disease, and some SSRIs (Lexapro). Low sodium
levels of 120 (135-145 normal) are a symptom of SIADH and can cause increased confusion. It
would be advisable to check the urine of this patient, a concentrated urine is expected with
SIADH. If left untreated, SIADH can cause increased confusion, hallucinations, seizures and
even coma.
The patients CO2 is elevated at 37 (23-29 normal) and this is likely related to her hx of COPD
and current smoker [Show Less]