Hantavirus pulmonary syndrome clinical findings: evaluating a surveillance case definition

Clinical cases of hantavirus pulmonary syndrome (HPS) can be challenging to differentiate from other acute respiratory diseases, which can lead to delays in diagnosis, treatment, and disease reporting. Rapid onset of severe disease occurs, at times before diagnostic test results are available. This study's objective was to examine the clinical characteristics of patients that would indicate HPS to aid in detection and reporting. Test results of blood samples from U.S. patients suspected of having HPS submitted to the Centers for Disease Control and Prevention from 1998-2010 were reviewed. Patient information collected by case report forms was compared between HPS-confirmed and test-negative patients. Diagnostic sensitivity, specificity, predictive values, and likelihood ratios were calculated for individual clinical findings and combinations of variables. Of 567 patients included, 36% were HPS-confirmed. Thrombocytopenia, chest x-rays with suggestive signs, and receiving supplemental oxygenation were highly sensitive (>95%), while elevated hematocrit was highly specific (83%) in detecting HPS. Combinations that maximized sensitivity required the presence of thrombocytopenia. Using a national sample of suspect patients, we found that thrombocytopenia was a highly sensitive indicator of HPS and should be included in surveillance definitions for suspected HPS. Using a sensitive suspect case definition to identify potential HPS patients that are confirmed by highly specific diagnostic testing will ensure accurate reporting of this disease.     

Minimal disease activity for rheumatoid arthritis: a preliminary definition

Agreement on response criteria in rheumatoid arthritis (RA) has allowed better standardization and interpretation of clinical trial reports. With recent advances in therapy, the proportion of patients achieving a satisfactory state of minimal disease activity (MDA) is becoming a more important measure with which to compare different treatment strategies. The threshold for MDA is between high disease activity and remission and, by definition, anyone in remission will also be in MDA. True remission is still rare in RA; in addition, the American College of Rheumatology definition is difficult to apply in the context of trials. Participants at OMERACT 6 in 2002 agreed on a conceptual definition of minimal disease activity (MDA): "that state of disease activity deemed a useful target of treatment by both the patient and the physician, given current treatment possibilities and limitations." To prepare for a preliminary operational definition of MDA for use in clinical trials, we asked rheumatologists to assess 60 patient profiles describing real RA patients seen in routine clinical practice. Based on their responses, several candidate definitions for MDA were designed and discussed at the OMERACT 7 in 2004. Feedback from participants and additional on-site analyses in a cross-sectional database allowed the formulation of 2 preliminary, equivalent definitions of MDA: one based on the Disease Activity Score 28 (DAS28) index, and one based on meeting cutpoints in 5 out the 7 WHO/ILAR core set measures. Researchers applying these definitions first need to choose whether to use the DAS28 or the core set definition, because although each selects a similar proportion in a population, these are not always the same patients. In both MDA definitions, an initial decision node places all patients in MDA who have a tender joint count of 0 and a swollen joint count of 0, and an erythrocyte sedimentation rate (ESR) no greater than 10 mm. If this condition is not met: * The DAS28 definition places patients in MDA when DAS28 < or = 2.85; * The core set definition places patients in MDA when they meet 5 of 7 criteria: (1) Pain (0-10) < or = 2; (2) Swollen joint count (0-28) < or = 1; (3) Tender joint count (0-28) < or = 1; (4) Health Assessment Questionnaire (HAQ, 0-3) < or = 0.5; (5) Physician global assessment of disease activity (0-10) < or = 1.5; (6) Patient global assessment of disease activity (0-10) < or = 2; (7) ESR < or = 20. This set of 2 definitions gained approval of 73% of the attendees. These (and other) definitions will now be subject to further validation in other databases.     

O'nyong-nyong fever in south-central Uganda, 1996-1997: clinical features and validation of a clinical case definition for surveillance purposes.

O'nyong-nyong (ONN) fever, caused by infection with a mosquito-borne central African alphavirus, is an acute, nonfatal illness characterized by polyarthralgia. During 1996-1997, south-central Uganda experienced the second ONN fever epidemic ever recognized. Among 391 persons interviewed and sampled, 40 cases of confirmed and 21 of presumptive, well-characterized acute, recent, or previous ONN fever were identified through active case-finding efforts or during a household serosurvey and by the application of clinical and laboratory criteria. Among confirmed cases, the knees and ankles were the joints most commonly affected. The median duration of arthralgia was 6 days (range, 2-21 days) and of immobilization was 4 days (range, 1-14 days). In the majority, generalized skin rash was reported, and nearly half had lymphadenopathy, mainly of the cervical region. Viremia was documented in 16 cases, primarily during the first 3 days of illness, and in some of these, body temperature was normal. During this epidemic, the combination of fever, arthralgia, and lymphadenopathy had a specificity of 83% and a sensitivity of 61% in the identification of cases of ONN fever and thus could be useful for surveillance purposes.     

Evaluation of surveillance case definition in the diagnosis of leptospirosis, using the Microscopic Agglutination Test: a validation study

Background  

Leptospirosis is endemic in both urban and rural areas of Sri Lanka and there had been many out breaks in the recent past. This study was aimed at validating the leptospirosis surveillance case definition, using the Microscopic Agglutination Test (MAT).     

Considerations for the definition of remission criteria in psoriatic arthritis

ObjectivesPsoriatic arthritis (PsA) is an autoimmune disease that can cause progressive structural damage of the joints and irreversible disability. The potentially achievable results of biologic therapy for PsA has led to the view that disease remission should be the goal of treatment. However, the heterogeneity of disease manifestations and need for validated outcome measures makes defining remission in PsA challenging. This article evaluates proposed criteria for defining remission in PsA and discusses how these criteria can be applied in clinical practice.MethodsA primary literature search was conducted in PubMed to identify articles discussing potential PsA treatment goals or targets, including minimal disease activity. English-language publications from the last 10 years were included in this assessment.ResultsThere are 5 clinical domains in PsA that must be considered when evaluating remission: synovitis, enthesitis, dactylitis, spondylitis, and psoriasis/nail psoriasis. Due to variability in the completeness of remission and time to achieve remission with different therapies between these domains, remission should be measured clinically through a combination of objective measures, or a composite assessment tool. Composite measures are more efficient than unidimensional instruments in measuring remission, but remission rates differ between the available composite indices.ConclusionAlthough the concept of remission as a treatment goal in PsA is gaining acceptance among rheumatologists, further work is necessary to develop a broadly acceptable definition of remission.     

Validation of the surveillance system for tuberculosis in Botswana.

SETTING: Gaborone and Francistown, Botswana, where surveillance data in the 1997 Electronic Tuberculosis (TB) Register suggest that 39% of pulmonary TB patients did not have pre-treatment sputum smear microscopy performed. OBJECTIVE: To determine the proportion of patients with reportedly missing pre-treatment sputum smear results in 1997 who had smears examined, and to identify stages in the system where results were lost. METHODS: Patients with pulmonary TB in 1997 who were missing pre-treatment sputum smear results in the Electronic TB Register were cross-matched with laboratory records; medical records were reviewed. RESULTS: Of 374 patients with pre-treatment sputum smear results missing, 224 (60%) actually had had a sputum smear examined in the laboratory. The proportion of pulmonary TB patients in Gaborone and Francistown who did not have sputum examined was therefore 16% instead of 39%. Most missing results (69%) had not been transcribed from the laboratory results onto the TB Treatment Card. Patients who had a negative smear result or who sought care at a clinic that was different from where their diagnostic evaluation had been initiated were more likely to have missing results. CONCLUSIONS: The actual performance of the Botswana National TB Programme with respect to sputum microscopy examination is much better than surveillance indicators suggest. In addition to sputum collection, proper recording of results needs reinforcement among health care workers to improve routine performance indicators.     

Preliminary definition of improvement in juvenile arthritis

Objective. To identify a core set of outcome variables for the assessment of children with juvenile arthritis (JA), to use the core set to develop a definition of improvement to determine whether individual patients demonstrate clinically important improvement, and to promote this definition as a single efficacy measure in JA clinical trials. Methods. A core set of outcome variables was established using a combination of statistical and consensus formation techniques. Variables in the core set consisted of 1) physician global assessment of disease activity; 2) parent/patient assessment of overall well-being; 3) functional ability; 4) number of joints with active arthritis; 5) number of joints with limited range of motion; and 6) erythrocyte sedimentation rate. To establish a definition of improvement using this core set, 21 pediatric rheumatologists from 14 countries met, and, using consensus formation techniques, scored each of 72 patient profiles as improved or not improved. Using the physicians' consensus as the gold standard, the chi-square, sensitivity, and specificity were calculated for each of 240 possible definitions of improvement. Definitions with sensitivity or specificity of <80% were eliminated. The ability of the remaining definitions to discriminate between the effects of active agent and those of placebo, using actual trial data, was then observed. Each definition was also ranked for face validity, and the sum of the ranks was then multiplied by the kappa statistic. Results. The definition of improvement with the highest final score was as follows: at least 30% improvement from baseline in 3 of any 6 variables in the core set, with no more than 1 of the remaining variables worsening by >30%. The second highest scoring definition was closely related to the first; the third highest was similar to the Paulus criteria used in adult rheumatoid arthritis trials, except with different variables. This indicates convergent validity of the process used. Conclusion. We propose a definition of improvement for JA. Use of a uniform definition will help standardize the conduct and reporting of clinical trials, and should help practitioners decide if a child with JA has responded adequately to therapy. We are in the process of prospectively validating this definition and several others that scored highly.     

The impact of the 1993 AIDS case definition on the completeness and timeliness of AIDS surveillance.

OBJECTIVE: To assess the impact of the 1993 change in the AIDS case definition on the completeness and timeframe of AIDS case reporting in San Francisco. DESIGN: Retrospective review of records: billing records, list of selected diagnostic codes, radiology logs, ophthalmology clinic records, and patient registries at a selection of hospitals, clinics, and physician offices. SETTING: Hospitals, public/community health clinics, and physician offices. MAIN OUTCOME MEASURES: The completeness of reporting and the median reporting delay was calculated for hospitals, clinics, and physician offices. RESULTS: Reporting was 97% complete. Reporting from physician offices was less complete (75%) than from other facilities. The median reporting delay was 1 month and was shorter for persons who met the 1993 AIDS case definition (1 month) than for persons who met the 1987 case definition (3 months). CONCLUSIONS: AIDS case reporting in San Francisco is highly complete but less so for persons diagnosed at physician offices. The 1993 AIDS case definition has resulted in more timely reporting. Health departments should consider efforts to improve reporting from private physician offices and should evaluate the use of laboratory-initiated CD4 reporting.     

Chronic fatigue syndrome: a working case definition

The chronic Epstein-Barr virus syndrome is a poorly defined symptom complex characterized primarily by chronic or recurrent debilitating fatigue and various combinations of other symptoms, including sore throat, lymph node pain and tenderness, headache, myalgia, and arthralgias. Although the syndrome has received recent attention, and has been diagnosed in many patients, the chronic Epstein-Barr virus syndrome has not been defined consistently. Despite the name of the syndrome, both the diagnostic value of Epstein-Barr virus serologic tests and the proposed causal relationship between Epstein-Barr virus infection and patients who have been diagnosed with the chronic Epstein-Barr virus syndrome remain doubtful. We propose a new name for the chronic Epstein-Barr virus syndrome--the chronic fatigue syndrome--that more accurately describes this symptom complex as a syndrome of unknown cause characterized primarily by chronic fatigue. We also present a working definition for the chronic fatigue syndrome designed to improve the comparability and reproducibility of clinical research and epidemiologic studies, and to provide a rational basis for evaluating patients who have chronic fatigue of undetermined cause.     

Validation of a multicenter computer-based surveillance system for hospital-acquired bloodstream infections in neonatal intensive care departments

Automated systems can facilitate surveillance for health care-associated infections. The New York Antimicrobial Resistance Project (NYARP) electronically monitors trends in bloodstream infections from 6 medical centers in New York, NY. To validate NYARP's data, episodes of health care-associated bloodstream infections detected by this system were compared with those obtained by an infection control practitioner performing an unrelated study in 2 participating neonatal intensive care departments. The sensitivity (84%), specificity (99%), and positive (84%) and negative (99%) predictive values of NYARP were excellent when coagulase-negative staphylococcal bloodstream infections were removed.