P1: SBT
0521779407-04 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:8
160 Arterial Embolus Ascariasis■Renal failure
➣Prevent with alkalinization of urine
➣Injury is acute tubular necrosis, resolves with support (dialysis)
■Amputation
➣Establishing flow to deep femoral artery may allow below-knee
rather than above-knee amputation
➣Above-knee amputation usually prevents later ambulation
■Bleeding complications (thrombolytic therapy)
➣Require discontinuation of thrombolytic therapyPrognosis
■Short-term
➣Mortality ranges from 7–34%, proportional to underlying disease
➣Amputation required in 15% despite aggressive therapy
■Long term
➣Recurrent emboli in 40–45% without anticoagulation and 10%
with anticoagulation
➣Long-term survival is limited (<60% at 5 years)Ascariasis..........................................
J. GORDON FRIERSON, MD
history & physical
History
■Life cycle: Eggs of Ascaris lumbricoides passed in the stool must incu-
bate in soil at least 2 weeks to be infectious, are ingested in contam-
inated food or water, hatch in small intestine. Larvae penetrate gut
wall, migrate to lungs in blood stream, penetrate alveolar-capillary
barrier, migrate up tracheobronchial tree, are swallowed and mature
in small intestine, where they mate and produce eggs. It takes 10–12
weeks from ingestion of eggs to production of eggs.
■Exposure: ingestion of food or water contaminated with infectious
eggs (i.e., after soil incubation)Signs & Symptoms
■During migration, cough, wheeze, fever, and rales may appear. In
intestinal phase, usually no symptoms, or non-specific indigestion,
epigastric discomfort. Worms may be passed rectally, or may migrate
up esophagus and be expectorated.