Three cases of cat scratch disease diagnosed by indirect immunofluorescence antibody assay and/or polymerase chain reaction of 16S rRNA gene of Bartonella henselae

Three suspected cases of cat scratch disease were diagnosed by indirect immunofluorescence antibody assay and/or polymerase chain reaction. Patient 1 was a 10-year-old female who presented swelling of the right axial lymph nodes with pain and fever. She kept a kitten, and many scratches were observed on her both legs and dorsum manus. Antibody titers against Bartonella (B.) henselae were 1:32 for IgM 3 weeks after the onset of the symptoms and 1:61 for IgG 8 weeks after the onset. The DNA for 16S rRNA type I of B. henselae was detected from the blood sample obtained 3 weeks after the onset of symptoms by polymerase chain reaction for the first time in Japan. Patient 2 was a 22-year-old female veterinary student with a cat scratch at the bottom of her neck by a male kitten. She developed a papule at the scratch, slight fever, and neck pain. Although both Bartonella-specific IgG and IgM antibodies were negative before the scratch, the IgG antibody titer rose to 1:512 14 weeks after the onset. B. henselae was isolated from the kitten and its DNA found to be for 16S rRNA type I by PCR. Patient 3 was a 23-year-old female veterinary student with a cat scratch on her left forearm. A small reddish papule developed on the scratch, and she experienced swelling of the left axial lymph node and pain. Both the IgG and IgM antibodies against B. henselae were negative before the cat scratch, and the IgG titer rose significantly to 1:128 and 1.1,024 in 2 and 5 weeks, respectively, after the onset of the symptoms.