Musculoskeletal manifestations of cat scratch disease.

BACKGROUND: Musculoskeletal manifestations (MMs) are considered to be rare in cat scratch disease (CSD) and are not well characterized. We aimed to study MMs of CSD. METHODS: A surveillance study performed over 11 years identified patients with CSD on the basis of compatible clinical presentation and confirmatory serological test or PCR results for Bartonella henselae. Patients with CSD who had MMs (i.e., myalgia, arthritis, arthralgia, tendinitis, osteomyelitis, and neuralgia) were compared with patients with CSD who did not have MMs (control subjects). RESULTS: Of 913 patients with CSD, 96 (10.5%) had MMs. Myalgia (in 53 patients [5.8%]) was often severe, with a median duration of 4 weeks (range, 1-26 weeks). Arthropathy (arthralgia and/or arthritis; in 50 patients [5.5%]) occurred mainly in the medium and large joints and was classified as moderate or severe in 26 patients, with a median duration of 5.5 weeks (range, 1-240 weeks). In 7 patients, symptoms persisted for >or=1 year; 5 developed chronic disease. Tendinitis, neuralgia, and osteomyelitis occurred in 7, 4, and 2 patients, respectively. Patients with MMs were significantly older than patients in the control group (median age, 31.5 years vs. 15.0 years). In multivariate analysis, age >20 years was associated with having any MM (relative risk [RR], 4.96; 95% confidence interval [CI], 2.79-8.8), myalgia (RR, 4.69; 95% CI, 2.22-9.88), and arthropathy (RR, 11.0; 95% CI, 4.3-28.2). Arthropathy was also associated with female sex (RR, 1.89; 95% CI, 1.01-3.52) and erythema nodosum (RR, 4.07; 95% CI, 1.38-12.02). CONCLUSIONS: MMs of CSD are more common than previously thought and affect one-tenth of patients with CSD. MMs occur mostly in patients aged >20 years and may be severe and prolonged. Osteomyelitis, the most well known MM of CSD is, in fact, the rarest.

Long-term serological analysis and clinical follow-up of patients with cat scratch disease.

A highly specific enzyme immunoassay (EIA) was recently described for use in the diagnosis of cat scratch disease (CSD). However, data regarding EIA antibody kinetics or its correlation with long-term clinical follow-up data are lacking. The association between antibody kinetics, clinical spectrum, and disease duration were studied in 98 patients with CSD. The median duration of follow-up was 35.3 weeks (range, 2-211.3 weeks). Results of EIA testing for detection of anti-Bartonella henselae immunoglobulin M (IgM) antibodies (detected in 53% of the patients) remained positive for < or =3 months. Therefore, the presence of IgM indicated acute infection. Titers of immunoglobulin G (IgG) also decreased over time; 25% of the patients remained seropositive for >1 year after the onset of CSD. Onset of CSD in patients with an IgG titer with an optical density of > or =1.0 occurred within the prior 12 months. No association was found between antibody titers or their kinetics and the clinical manifestations or duration of disease. EIA allows for the identification of atypical manifestations of CSD that were unrecognized before the use of serological assays. Complete recovery from these manifestations may take months. Results of this study provide additional data supporting the utility of EIA in the serodiagnosis of CSD.