<prompt> Skin test useful in Hydatid disease is?Casonis testSchick testPatch testDick s test  <response>: ANSWER: A Casonis testREF: Panikers 6th ed p. 149The Casoni test is a skin test used in the diagnosis of hydatid disease. The test involves the intradermal injection of 0.5 ml of sterilised fluid from hydatid cysts. A wheal response occurring at the injection site within 20 minutes is considered positive. The test is positive in about 90 of cases of hydatid disease affecting the liver, but positive in less than 50 of patients with hydatid disease elsewhere in the body; false positive results are also common. Consequently, serological tests are nowr generally used.Dicks test: Scarlet fever Schicks test: Diphtheria 