Fall in circulating antibody levels in leprosy during acute attacks

The authors studied serodiagnostic changes using immunofluorescence during onset of leprosy, repeating serodiagnosis using immunofluorescence on Stephansky's bacillus in patients followed from onset or subsidence of the disease. The 9 first cases reported show a low level of serodiagnostic positivity during reactionary relapses, which rises to the usual figures found in developing leprosy as soon as the reactionary process has subsided. Five cases are cited to demonstrate the low levels seen during the clinically reactionary phase. In the first days of the reactionary phase the antibody level falls in all these cases, rising again to a normal level 5 or 6 wk later. It thus seems that the fall in circulating antibodies preceeds or accompanies local deposition of antibodies in the lesions