Pilot field testing of the chronic pain classification for ICD-11: the results of ecological coding.

BACKGROUND: A task force of the International Association for the Study of Pain (IASP) has developed a classification of chronic pain for the ICD-11 consisting of seven major categories. The objective was to test whether the proposed categories were exhaustive and mutually exclusive. In addition, the perceived utility of the diagnoses and the raters' subjective diagnostic certainty were to be assessed. METHODS: Five independent pain centers in three continents coded 507 consecutive patients. The raters received the definitions for the main diagnostic categories of the proposed classification and were asked to allocate diagnostic categories to each patient. In addition, they were asked to indicate how useful they judged the diagnosis to be from 0 (not at all) to 3 (completely) and how confident they were in their category allocation. RESULTS: The two largest groups of patients were coded as either chronic primary pain or chronic secondary musculoskeletal pain. Of the 507 patients coded, 3.0% had chronic pain not fitting any of the proposed categories (97% exhaustiveness), 20.1% received more than one diagnosis. After adjusting for double coding due to technical reasons, 2.0% of cases remained (98% uniqueness). The mean perceived utility was 1.9 ± 1.0, the mean diagnostic confidence was 2.0 ± 1.0. CONCLUSIONS: The categories proved exhaustive with few cases being classified as unspecified chronic pain, and they showed themselves to be mutually exclusive. The categories were regarded as useful with particularly high ratings for the newly introduced categories (chronic cancer-related pain among others). The confidence in allocating the diagnoses was good although no training regarding the ICD-11 categories had been possible at this stage of the development.

Quantification of periodontal pathogens in vascular, blood, and subgingival samples from patients with peripheral arterial disease or abdominal aortic aneurysms.

BACKGROUND: The aim of this investigation is to quantify periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Campylobacter rectus, and Tannerella forsythia) in vascular, blood, and subgingival samples. As a secondary objective, two molecular bacterial identification methods (nested polymerase chain reaction [PCR] and quantitative PCR [qPCR]) are compared. METHODS: Seventy consecutive patients provided a vascular lesion, a blood sample, and 36 subgingival samples. Bacterial DNA was extracted, and qPCR was used to determine the prevalence and amounts of the target pathogens in each sample. Nested PCR was performed only in the samples from vascular lesions. Periodontal examination was performed in 42 patients. Mann-Whitney U or χ(2) tests were used to compare microbiologic results according to periodontal diagnosis. RESULTS: All targeted periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, T. forsythia, or C. rectus) were detected in subgingival samples, with a prevalence rate of 72.2%, 47.2%, 74.3%, and 82.9%, respectively. In 7.1% and 11.4% of vascular and blood samples, bacterial DNA was detected. One patient was positive for A. actinomycetemcomitans in the three types of samples. No differences were found in the levels of targeted bacteria when comparing patients with and without periodontitis. Prevalence rates obtained with nested PCR were significantly higher than those obtained with qPCR. CONCLUSIONS: The presence of A. actinomycetemcomitans was demonstrated in vascular, blood, and subgingival samples in one of 36 patients. These results, although with a very low frequency, may support the hypothesis of a translocation of periodontal pathogens from subgingival microbiota to the bloodstream and then to atheromatous plaques in carotid or other peripheral arteries. Nested PCR is not an adequate method for identifying DNA of periodontal pathogens in low quantities because of the high number of false-negative results.