Hypertension — 2º Causes

SUMMARY OF WORK-UP FOR HYPERTENSION

For Everyone w/ HTN *

  • History
  • Physical Exam
  • Chemistry Panel
  • TSH
  • Urinalysis

*  See Below for Clues generated by this work-up

For These Patients

  • HTN first Dx’d <30 y.o.
  • Uncontrolled B/P on 4 meds
  • Abnormal Optic Fundi

Order

  • Renal Ultrasound
  • Aldosterone : Renin Activity
  • 24-hr. Urine for Catecholamines & Metanephrines
  • 24-hr. Urine for Cortisol

Suspect RAS If:

  • >50 y.o. and new loss of control
  • Creat. ↑ 50% 3-5 d after ACE-I
  • Recurrent sudden pulmonary edema

Order:

  • Duplex Sono;  OR
  • Send to Nephrology

CONDITIONS TO SUSPECT FROM BASIC WORK-UP

1. Clues from History:
  • Paroxysms of severe H/A + palpitations + diaphoresis →  r/o Pheochromocytoma
  • Excessive daytime drowsiness →  r/o Sleep Apnea (if also snores)
  • Meds (chronic): esp. Estrogens, NSAIDs, Anti-depressants, Decongestants, Stimulants
2.  Clues From Physical Exam:
  • Cushingoid Features  →  r/o Cushing’s
  • Diastolic murmur at L sternal border →  r/o Aortic Insufficiency
  • Abdominal Bruit: systolic + diastolic →  Renal Artery Stenosis
  • Pulses (palpate brachial & femoral pulses simultaneously):  Delayed femoral →  r/o Coarctation of Aorta
  • Optic Fundoscopy → abnormalities suggest severe HTN (r/o lots of causes)
3. Clues From Chemistry Panel:
  • ↑ Creatinine suggests Renal Disease
  • ↑ Calcium suggests Hyperparathyroidism
  • ↓ Potassium → r/o 1° Aldosteronism
  • ↑ Glucose → r/o Cushing’s if stigmata on PE (otherwise, just Dx diabetes)

4.  TSH: ↑ = Hypothyroidism, ↓ = Hyperthyroidism

5.  Urinalysis:
  • Proteinuria suggests underlying Renal Disease
  • Proteinuria + Hematuria → Glomerulonephritis
  • Red cell casts → Gomerulonephritis

TESTS TO R/O SECONDARY CAUSES OF HYPERTENSION

 **  Hypo- / Hyperthyroidism
→  TSH
 
**  Renal Disease
→  Creatinine; Proteinuria; Renal Ultrasound
 
**  1° Aldosteronism
→  Ratio of plasma Aldosterone-to-Renin Activity
 
**  Medications
→  History
 
**  Hyperparathyroidism
→  Serum calcium (and albumin); serum PTH
 
**  Pheochromocytoma
→  24 hr. Urine for Catecholamines, Metanephrines
 
**  Cushing’s Syndrome
→  24 hr. Urine for Cortisol
 
**  Obstructive Sleep Apnea
→  Polysomnogram
 
**  Renal Artery Stenosis
→  Duplex Ultrasound; MR / CT Angiogram
 
**  Aortic Insufficiency
→  Cardiac auscultation; Echocardiogram
 
**  Coarctation of Aorta
→  Echocardiogram; MR / CT Angiogram

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