Hookworm in Emergency Medicine Clinical Presentation
- Author: Anika Baxter Tam, MD; Chief Editor: Rick Kulkarni, MD more...
History
Most infected individuals are asymptomatic.
In the first 7-10 days following infection, patients may notice "ground itch" (ie, itchy papules where the skin was penetrated by larvae).
Infected patients are not directly contagious because eggs require a brief period outside the body to hatch into their infective larval form.
Patients may have a history of wearing open footwear or walking barefoot in endemic areas.
Early symptoms - Larval migration phase (1-5 d)
- The onset of ground itch with localized maculopapular eruption ("ground itch") is noted.
- Low-grade fever may occur.
- Migration of worms through the lungs may produce a mild cough.
- Pulmonary inflammatory response can lead to wheezing.
Late symptoms
GI discomfort secondary to irritation may occur as the worms pass into the gastrointestinal tract.
Hookworm anemia is usually due to iron deficiency and does not develop until iron reserves are depleted.
About one half of the iron expelled by the worm is resorbed; the remainder is lost.
A large worm burden and a history of poor iron intake increase the likelihood of significant anemia.
The symptoms of anemia often include fatigue and dyspnea. In rare cases, anemia may provoke ischemic symptoms such as angina or claudication.
In high prevalence areas, all anemic patients have hookworms; however, not all patients infected with hookworms have hookworm anemia.
Physical
Physical findings in the early (larval migration) and late (established GI infection) stages of the disease are different.
Early infection (larval migration)
- Small, pruritic papules are observed at the larval skin entry site (usually feet).
- Wheezing may be triggered when the worms first break through from the venous circulation into the pulmonary air spaces.
Established infection (adult/GI phase)
- Mild abdominal tenderness
- Pallor (hookworm anemia)
- Pale conjunctiva (hookworm anemia)
- Tachycardia (hookworm anemia)
Causes
The larvae enter through bare skin upon exposure to fecally contaminated soil that contains infective larva.
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