infectious diseases
Hookworm Infection
Diagnosis of Hookworm Infection
Microscopic examination of stool produce thin-shelled oval eggs that are readily detected in fresh stool. Concentration procedures are needed to diagnose light infections. If the stool is not kept cold and examined within several hours, the eggs may hatch and release larvae that must be differentiated from those of Strongyloidiasis . Although the three hookworm species that infect humans can be differentiated by molecular probes, the ova are indistinguishable, and a species-specific diagnosis is not made in clinical laboratories. Eosinophilia is often present in people infected with hookworms. During the prepatent period of infection (ie, the 5 to 9 weeks between penetration of larvae and appearance of eggs in the stool), eosinophilia may be the only laboratory abnormality. Hookworm infestation is an important consideration in the differential diagnosis of eosinophilia in immigrants or travelers returning from endemic regions where sanitation is poor. Nutritional status, anemia, and iron stores should be evaluated (see Diagnosis ). Diagnosis of cutaneous larva migrans is based on the clinical manifestations. Ova are not present in the stool. 