Hypertriglyceridemia

Background

  • ~5% of acute pancreatitis caused by high triglycerides[1]
  • Etiologies
    • Familial hypertriglyceridemia, autosomal dominant with variable penetrance
    • Secondary forms
  • TG levels > 2000mg/dL almost always have both secondary and genetic form[2]
  • 1.7% of US estimated to have [TG] between 500-2000[3]
Hypertriglyceridemia green top.jpg
  • May present with normal serum lipase levels

Pathophysiology

  • Excess TG hydrolyzed by increased concentration of pancreatic lipase
  • Produces increased concentration of free fatty acids that exceeds binding capacity of albumin
  • Micelles are formed that attack platelets, vascular endothelium and acinar cells
  • Ischemia and pancreatic injury result
  • An acidic environment potentiates free fatty acid toxicity

Clinical Features

Hypertriglyceridemic Pancreatitis

Signs/symptoms of pancreatitis

  • Pain is the most common symptom and is often characterized by:[4]
    • Persistent
    • Localizes to epigastric area, around waist, RUQ, or occasionally LUQ
    • Radiates to back
    • The onset may be less abrupt and the pain poorly localized
  • Nausea/vomiting noted in most
  • Abdominal distention is frequent complaint
  • Cullen sign (ecchymosis of periumbilical region) - intrabdominal hemorrhage
  • Turner sign (ecchymosis of flanks) - retroperitoneal hemorrhage
  • Pulmonary Findings
    • Hypoxemia, ARDS, tachypnea
    • Indicates severe pancreatitis
      • Diaphragmatic inflammation, pancreatico-pleural fistula

Differential Diagnosis

Epigastric Pain


Evaluation

  • Triglycerides; Severely elevated (at least >500 mg/dL, generally >1,000 mg/dL)
    • Lipids in serum may interfere with other lab tests
      • Falsely low Na+, amylase

Pancreatitis workup

  • Rule out other causes of pancreatitis (e.g. gallstone pancreatitis)
  • In general, if triglycerides >1000, can assume this is cause of pancreatitis
  • Lipase level >3x upper limit of normal
    • Sensitivity 82-100%, specificity 82-100%[5]
    • Negative lipase does not exclude pancreatitis in chronic/recurrent disease
    • Absolute value not associated with prognosis or severity
  • Characteristic findings on ultrasound or CT


Management

Management of acute pancreatitis in the setting of hypertriglyceridemia

  • Evidence for management based on case series and reports[6][7]
  • Insulin drip - most dramatic and rapid intervention, with reduction within 24 hrs
    • 5-10 units/hr with or without dextrose infusion to maintain BSs ~150mg/dL
    • May require higher dosages for diabetics, 0.1–0.3 U/kg/hr
    • Titrate to BS 140–180mg/dL[8]
  • Treat concurrent hypothyroidism if present
  • Pain control
  • Niacin 500mg QD
  • Gemfibrozil or fenofibrate
  • Max dose statin, 81mg ASA
  • Heparin q8 SC, effect short-lived
  • NPO initially
  • May advance diet starting at TG level < 1000mg/dL with resolution of abdominal pain/pancreatitis symptoms
    • No fat diet
    • Low calorie diet
  • Follow TG levels, goal < 500-1000mg/dL by discharge

Plasma exchange

  • Therapeutic plasma exchange, for 1-3 days (sickest patients)
  • For euglycemic patients, not routine first line
  • Requires central venous access

Disposition

  • Asymptomatic hypertriglyceridemia is treated as an outpatient
  • For acute pancreatitis, ICU or step-down for frequent labs, insulin drip

See Also

External Links

References

  1. Yadav D, Pitchumoni CS. Issues in hyperlipidemic pancreatitis. J Clin Gastroenterology 2003;36:54-62.
  2. Yuan et al. Hypertriglyceridemia: its etiology, effects and treatment. CMAJ 2007;176:1113-1120.
  3. Brown, Virgil W. Et al. “Clinical Lipidology Roundtable Discussion: Severe Hypertriglyceridemia.” Journal of Clinical Lipidology 2012; 6:397-408
  4. Cite error: Invalid <ref> tag; no text was provided for refs named NEJM
  5. Yadav D, Agarwal N, Pitchumoni CS. A critical evaluation of laboratory tests in acute pancreatitis. Am J Gastroenterol. 2002 Jun;97(6):1309-18.
  6. Santana YR et al. Treatment of severe hypertriglyceridemia with continuous insulin infusion. Case Reports in Critical Care. June 2011.
  7. Poonuru S et al. Rapid Reduction of Severely Elevated Serum Triglycerides with Insulin Infusion, Gemfibrozil and Niacin. Clin Med Res. 2011 Mar; 9(1): 38–41.
  8. Schaefer EW. Management of Severe Hypertriglyceridemia in the Hospital: A Review. Journal of Hospital Medicine Vol 7|No 5|May/June 2012.