Absite Topic Review

1. Absite Topic Review Nir Hus, MD, PhD. 12/1/08

2. Characteristics of 1o Hyperaldosteronism. • Conn syndrome (1o aldosteronism) – • HTN, • Na – retention, • K+ & hydrogen ion excretion  Hypokalemia, • caused by hypersecretion of the mineralocorticoid aldosterone. • Hypokalemia <3.5 mWq/L • Kaliuresis >30 mEq /day • Aldosterone > 15 ng/dL • Normal cortisol • Upright plasma renin activity < 3 ng/mL / hr corroborates the diagnosis. • CT scan or MRI. Nir Hus

3. Characteristics of 1o Hyperaldosteronism. • Aldosterone-producing adrenal adenoma is the cause of 1o aldosteronism in 2/3 of cases. • Surgically corrected causes of HTN. • Idiopathic Bi. Adrenal hyperplasia accounts for the rest. • Differentiation between Bi. Idiopathic and adrenal adenoma is of extreme importance since the adenoma is surgically treated whereas the Bi. Condition is medically treated. • Adrenocortical CA & autosomal dominant glucocorticoid suppressible aldosteronism are rare causes of 1o aldosteronism. Nir Hus

4. Finding Associated w/ Gastric Ulcer bleeding. • Pt. in ICU are at increased risk for stress-induced mucosal ulceration and UGI bleed. • Risk factors: • Head injury – Cushing ulcers. • Burns > 30% – Curling ulcers. • Previous Hx of PUD. • NSAIDs or steroids. • Renal failure. • Shock • Portal HTN. • Coagulopathy. Nir Hus

5. Finding Associated w/ Gastric Ulcer Rebleeding. • Dieulafoy’s Lesion: • Large tortuous, submucosal artery usually in the proximal stomach. • Pulsation causes ulceration of the overlaying mucosa, leading to intraluminal bleeding. • Endoscopy is diagnostic and theraputic, otherwise try embolization. • Sx for treatment failure. Nir Hus

6. Amebic Abscess Liver • Amebiasis is largely a disease of tropical and developing countries, but it is also a significant problem in developed countries because of immigration and travel between countries. • E. histolytica is endemic in Mexico, India, Africa, and parts of Central and South America. • E. histolytica is a protozoan and exists as a trophozoite or as a cyst. • All other species in the genus Entamoeba are considered nonpathogenic, and not all strains of E. histolytica are considered virulent. Nir Hus

7. Amebic Abscess Liver • Ingestion of E. histolytica cysts through a fecal-oral route is the cause of amebiasis. • Humans are the principal host, and the main source of infection is human contact with a cyst-passing carrier. • Contaminated water and vegetables are also a route of human infection. • Once ingested, the cysts are not degraded in the stomach and pass to the intestines where the trophozoite is released and passed on to the colon. In the colon, the trophozoite can invade mucosa, resulting in disease • Epidemiologic studies specifically addressing E. histolytica infections estimate that as many as 55% of a population in endemic regions are infected, although less than half are symptomatic. • The trophozoites reach the liver through the portal venous system. Nir Hus

8. Amebic Abscess Liver • Hepatic amebic abscess is essentially the result of liquefaction necrosis of the liver, producing a cavity full of blood and liquefied liver tissue. The appearance of this fluid is typically described as anchovy sauce, and the fluid is odorless unless secondary bacterial infection has taken place. • The typical clinical picture is a patient 20 to 40 years of age who has recently traveled to an endemic area, with fever, chills, anorexia, right upper quadrant pain and tenderness, and hepatomegaly. The abdominal pain is typically constant, dull, and localized to the right upper quadrant. Nir Hus

9. Amebic Abscess Liver • Abdominal CT scan is the gold standard and is helpful in differentiating amebic from pyogenic abscess. • Rim enhancement noted in pyogenic abscess. Nir Hus

10. Amebic Abscess Liver • The mainstay of treatment for amebic abscesses is metronidazole (750 mg orally three times per day for 10 days), which is curative in more than 90% of patients. Nir Hus