Not used in leptospirosis -

. Ans. is 'd' i.e., Weil felix reaction A definite diagnosis of leptospirosis is based either on isolation of the organism from the patient or on seroconversion or a rise in antibody titer in microscopic agglutination test (MAT). Other methods used for diagnosis are :? Microscopic demonstration - Leptospires may be visualized in clinical material by dark - field microscopy or by immunofluorescence or light microscopy after appropriate staining. - Approximately 104 leptospires / ml are necessary for one cell per field to be visible in dark - ground microscopy (DGM). Microscopy of blood is of value only during the first few days of acute illness, while leptospiremia occurs. Polymerase chain reaction - PCR techniques have been developed but so for have not found wide spread use outside research and reference laboratories. Molecular typing - There has been great interest in molecular methods for identification and subtyping. Other methods used for diagnosis are :? Microscopic demonstration - Leptospires may be visualized in clinical material by dark - field microscopy or by immunofluorescence or light microscopy after appropriate staining. - Approximately 104 leptospires / ml are necessary for one cell per field to be visible in dark - ground microscopy (DGM). Microscopy of blood is of value only during the first few days of acute illness, while leptospiremia occurs. Polymerase chain reaction - PCR techniques have been developed but so for have not found wide spread use outside research and reference laboratories. Molecular typing - There has been great interest in molecular methods for identification and subtyping.