infectious diseases
Trichinosis
Diagnosis of Trichinosis
Enzyme immunoassay Rarely muscle biopsy No specific tests to diagnose the intestinal stage ofTrichinellaare available. After the 2nd week of infection, a muscle biopsy may detect larvae and cysts but is seldom necessary. Diffuse inflammation in muscle tissue indicates recent infection. A number of serologic tests have been used, but enzyme immunoassay (EIA) usingT. spiralisexcretory-secretory (ES) antigen seems to be the quickest way to detect the infection and is used in the United States. Antibodies are often not detectable for the first 2 to 8 weeks of infection, so tests should be repeated at weekly intervals if results are initially negative. Because antibodies may persist for years, serologic tests are of most value if they are initially negative and then positive. Serologic tests and muscle biopsy are complementary tests: Either one can be negative in a given patient with trichinosis. Skin testing with larval antigens is unreliable. Muscle enzymes (creatine kinase and lactic dehydrogenase [LDH]) are elevated in 50% of patients and correlate with abnormal electromyograms. Eosinophilia is common but has numerous infectious and noninfectious causes (see table Trichinosis must be differentiated from Acute Rheumatic Fever , acute Febrile illnesses such as Tuberculosis (TB) , Aspiration Pneumonitis and Pneumonia None Neurologic manifestations of Overview of Meningitis , Eosinophilia due to neoplasms, 