P. Vinceneux

Reliability of Tuberculin Skin Test Measurement

The tuberculin skin test has many potential sources of error and variability. Standardization of the tuberculin reagent and the meaning of the test results have been considered in some detail [1, 2], but little attention has been paid to the reading itself [3-10]. Measurement of the induration, however, is one of the most important potential sources of error. If the customary technique of palpation is used, the margins of the induration may be difficult to define. The alternative ballpoint-pen method, although advocated as more reliable than palpation [3], has not been discussed in official statements on tuberculosis [1, 2]. We investigated the reliability of the ballpoint-pen technique and compared this technique with the palpation method. Methods Patients and Procedures Patients and health care personnel who were in an internal medicine department and needed a tuberculin skin test were invited to participate. Persons who had received bacille CalmetteGurin vaccine were enrolled preferentially. Ninety-six persons who provided informed consent ultimately participated in the study. Tuberculin Skin Tests and Measurement Methods Ten units of tuberculin from Pasteur Merieux, Lyon, France (corresponding to the recommended 5 IU of purified protein derivative tuberculin), were injected intradermally on the volar surface of the forearm (Mantoux technique) [11]. Readings were done on the third day after the test was administered, and the diameter of induration was measured along the long axis of the forearm. Two experienced investigators each independently did three measurements. The first two measurements were taken with a blinded caliper using the ballpoint-pen technique [3]. With this technique, a medium-point ballpoint pen is used to draw a line starting 1 to 2 cm away from the skin reaction and moving toward its center. When the pen reaches the margin of the induration, an increased resistance to further movement is felt and the pen is lifted. The procedure is repeated on the opposite side of the skin reaction. The distance between the ends of the opposing lines at the margins of the induration is measured. In our study, the lines were erased and the measurement process was repeated. The lines were then erased again, and the third measurement was done by palpation [2]. To reproduce the usual conditions of testing, we used a flexible ruler. The data were collected during eight sessions; 11 to 14 participants were tested per session. To reduce the chance that an observer would remember previous readings, three things were done. First, the results of measures that were obtained with the blinded caliper were recorded by a third investigator. Second, the first ballpoint-pen measure was done for all participants at each session, then the second ballpoint-pen measure, and then the palpation measure. Third, before the second and third readings, the third investigator verified that no minor landmarks persisted. Statistical Analysis To analyze the reliability of quantitative data, we used statistical methods that have been described elsewhere [12]. Intraclass correlation coefficients and their 95% CIs were computed using SAS soft-ware (SAS Institute, Cary, North Carolina) [13]. Induration diameters were used to classify skin reactions as positive or negative according to the 5-, 10-, and 15-mm cutoff points that have been recommended as indicating positivity in various situations [2]. Reliability was then assessed with coefficients [14]. We also used a graphical analysis that focuses on the mean and the variation in the differences between repeated measurements [15]. Mean differences and the SD of the differences were calculated. An area of imprecision that was determined on the basis of the SD of the differences was placed around the arbitrarily chosen 10-mm cutoff value (10 mm 1.96 SD). If a first measurement fell within this area, particularly at or about the cutoff value, the likelihood that the second measurement would be sufficiently different to change the result of the tuberculin skin test from negative to positive (or vice versa) was high. Conversely, such reclassification would occur in only 5% of the cases that had values outside this area. Results Because of the study design, only 27 participants (28%) did not react to the tuberculin skin test. Reliability of the Ballpoint-Pen Technique Intraobserver Reliability In persons who had no response to the tuberculin skin test, the intraobserver reliability was perfect (intraclass correlation coefficient = 1.0). Intraclass correlation coefficients were high for both observers and decreased only slightly after the nonresponders were excluded. The coefficients also suggested good intraobserver reliability but were lower with the 10- and 15-mm cutoff values than with the 5-mm cutoff value (Table 1). Table 1. Reliability Study of the Ballpoint-Pen and Palpation Methods of Induration Measurement for the Tuberculin Skin Test The top panel of Figure 1 shows the difference between the two readings for each participant that were done by the first observer (range, 6.8 to +3.5 mm) plotted against the corresponding mean for each participant. The level of intraobserver reliability was evaluated by determining the 95% CI ( 2.68 to +2.96 mm) within which most of the differences were seen. This means that 5% of the time, the second measure of the test results done by using the ballpoint-pen method would be at least 2.7 mm less than or 3.0 mm more than the first one. This lack of reliability could lead to the reclassification of a negative tuberculin skin test result as positive or vice versa. Figure 1. Top. Middle. Bottom. As shown in the top panel of Figure 1, an area of imprecision that straddles the cutoff value (7.2 to 12.8 mm for a 10-mm cutoff value) was generated using the SD of the differences. Test results for 8 of the 69 patients (12%) were reclassified. The first measurement for 30 of the 69 patients (43.5%) fell within this area of imprecision; 7 of those 30 patients (23.3%) were among the 8 patients whose test results were reclassified. Interobserver Reliability Agreement between observers, estimated by using the intraclass correlation and coefficients, was high (Table 1). The first ballpoint-pen measures made by the two observers were used for these analyses. Differences between first measures done by the two observers were between 5.1 and +7.3 mm (Figure 1, middle). The 95% CI of the differences was 3.39 to +3.69 mm; this means that 5% of the time, the result of a second tuberculin skin test measurement by another investigator would be at least 3.4 mm more than or 3.7 mm less than that of a first investigator. As in the top panel of Figure 1, an area of imprecision (6.5 to 13.5 mm) is shown in the middle panel of Figure 1; this area is slightly broader than that calculated for intraobserver reliability. Test results for 8 of the 69 patients (12%) were reclassified. The first measurement for 40 of the 69 patients (58%) fell within this area of imprecision; 7 of those 40 patients (17.5%) were among the 8 patients whose results were reclassified. Reliability of the Palpation Technique Except for the coefficients at the 15-mm cutoff, assessment of agreement between observers showed that all reliability coefficients obtained with the palpation technique were slightly lower than those obtained with the ballpoint-pen method (Table 1). The 95% CI of the differences between the measures of the two observers was 4.6 to +5.2 mm (Figure 1, bottom). This resulted in a much broader area of imprecision for the readings (5.1 to 14.9 mm). Test results were reclassified for 12 of the 69 patients (17.4%). The first measure of 43 of the 69 patients (62.3%) fell within this area of imprecision, and the 12 patients whose test results were reclassified were among those 43 (27.9%). Agreement between Ballpoint-Pen and Palpation Methods Although all the intraclass correlation coefficients were high, the coefficients that were produced after persons with no response to the test were excluded suggested only moderate to good reliability (Table 1). The 95% CIs of the differences between the first ballpoint-pen and the palpation measures were 3.0 to +4.1 mm for readings taken by the first observer and 2.5 to +3.9 mm for readings taken by the second observer. The areas of imprecision for the measurements were from 6.4 to 13.6 mm for readings taken by the first observer and 6.8 to 13.2 mm for readings taken by the second observer. Reclassification occurred in 8 of 69 patients (12%) for both observers. Discussion In our study, the ballpoint-pen technique was reliable, as evaluated by global reliability coefficients. However, the graphical analysis provided a more meaningful representation of the level of variation. Intraobserver reliability may be the most important factor for such diagnostic tests as the tuberculin skin test, which are usually done by only one examiner for any given patient. Lack of reliability may lead to the frequent reclassification of results, particularly if readings are at or about the cutoff values. Reliability coefficients were slightly higher for the ballpoint-pen technique than for the palpation method. In addition, the 95% CI of the differences of the measures taken by the two observers was 38% broader for the palpation method than for the ballpoint-pen technique; this could result in more frequent misclassification. Only one study [10] has addressed the interobserver reliability of the ballpoint-pen technique. That study relied on simple correlation coefficients to determine reliability. Reanalysis of the data from that study provided a coefficient of 0.74 (using a cutoff point of 10 mm). Previous studies of the reliability of the palpation method [5, 6, 10] have also been restricted primarily to the assessment of interobserver agreement and have provided conflicting results. Recalculation from the data of one large survey of six studies on tuberculin skin testing [4] gave

Helicobacter cinaedi Septic Arthritis and Bacteremia in an Immunocompetent Patient

We report on the first case of documented Helicobacter cinaedi septic arthritis in an immunocompetent heterosexual young man. The patient presented no identified risk factor except for contact with animals that have been incriminated as a possible source of infection, particularly for these patients. Despite prolonged bacteremia, the response to long-term therapy with ciprofloxacin and rifampin was excellent.

Tuberculosis, of the sacroiliac joint: clinical features, outcome, and evaluation of closed needle biopsy in 11 consecutive cases

Sacroiliac joint (SIJ) involvement has been reported in up to 9.7 percent of patients with skeletal tuberculosis. Lack of awareness of this now uncommon form of infection often leads to diagnostic delay and increased morbidity. Eleven consecutive cases of SIJ tuberculosis are reported; clinical and radiologic features, diagnosis, treatment, and outcome are discussed. Buttock pain was the presenting complaint in all patients. However, radicular pain in the lower back (seven patients) or lower limb (10 patients) was common and in one patient precipitated an unnecessary surgical intervention. SIJ tuberculosis is frequently an isolated phenomenon. Therefore, direct sampling of the SIJ is necessary to establish the diagnosis. The recently described technique of closed needle biopsy of the SIJ was employed in all 11 patients and established the diagnosis in nine of the 11.

Manifestations cliniques et biologiques de la maladie de Still de l’adulte

Resume Une triade La maladie de Still de l’adulte (MSA) est une affection rare qui associe classiquement une fievre elevee hectique, une eruption cutanee evanescente constituee de petites macules roses saumonees, et des arthrites. Des manifestations systemiques nombreuses Une douleur pharyngee est frequente et contribue souvent a egarer le diagnostic. Un peu plus de 60 % des patients ont des adenopathies mobiles indolores, le plus souvent cervicales. L’atteinte hepatique est frequente et ne se traduit le plus souvent que par une cytolyse moderee. Toutefois, la possibilite d’hepatites cytolytiques gravissimes justifie une surveillance rigoureuse de la biologie hepatique. Parmi les nombreuses autres manifestations systemiques decrites, il faut retenir l’atteinte pericardique parfois responsable d’une tamponnade, l’atteinte du parenchyme pulmonaire parfois responsable d’un syndrome de detresse respiratoire aigue, les rares atteintes neurologiques le plus souvent sous la forme d’une meningite aseptique ou d’une paralysie d’un nerf crânien. Au point de vue biologique Le syndrome inflammatoire est constant et tres marque, et il existe classiquement une franche hyperleucocytose a polynucleaires neutrophiles. L’enquete infectieuse est negative et les examens immunologiques generalement non contributifs. L’elevation de l’IL-18 pourrait avoir un interet diagnostique et pronostique. C’est surtout la presence d’une hyperferritinemie, bien plus elevee que ne le voudrait le seul syndrome inflammatoire, qui a une valeur diagnostique, surtout lorsqu’elle s’associe a une diminution de sa fraction glycosylee, en deca de 20 %.

Diagnostic, évolution et pronostic, pathogénie et traitement de la maladie de Still de l’adulte

Resume Incertitudes diagnostiques Malgre une meilleure connaissance de l’affection, le diagnostic de maladie de Still de l’adulte (MSA) reste encore le plus souvent un diagnostic d’elimination. De nombreux criteres diagnostiques ont ete publies et les plus usites sont ceux proposes par Yamaguchi, meme s’ils ne prennent pas en compte l’hyperferritinemie et l’abaissement de sa fraction glycosylee et si les criteres d’exclusion sont difficiles a satisfaire. Evolution imprevisible Trois formes evolutives sont classiquement decrites : monocyclique, intermittente avec des poussees successives articulaires et/ou systemiques, chronique, principalement sous la forme d’une polyarthrite chronique. Le pronostic vital est parfois mis en jeu par certaines manifestations systemiques particulierement graves ou par le developpement d’une amylose, tandis que le pronostic fonctionnel peut etre compromis par une atteinte articulaire destructrice particulierement frequente dans les formes d’evolution chronique. La pathogenie reste en grande partie inconnue. Incertitude des therapeutiques Le traitement de la MSA demeure empirique en l’absence d’essais controles, difficiles a envisager compte tenu de la rarete de la maladie. Les anti-inflammatoires non steroidiens meritent d’etre essayes dans les formes de severite moderee mais ils sont rarement suffisants. Une corticotherapie est necessaire chez environ 80 % des patients. Parmi les traitements dits “de fond”, c’est certainement le methotrexate qui reste le plus interessant. La place des nouvelles molecules anti-TNF reste a preciser.

The Vote of Acute Medical Inpatients A Prospective Study

Objective: There may be ethical issues associated with allowing certain inpatients to vote as some may be cognitively impaired. During the 2007 elections in France, we conducted a prospective observational study on voting among hospitalized patients. Method: Patients hospitalized in an Internal Medicine and Geriatric Department on election day were included. The primary outcome was the turnout among registered inpatients, and secondary outcomes were Mini-Mental State Examination (MMSE) scores and reasons for abstention. Results: Of 142 inpatients (mean age 73 years), 84 were eligible to vote, and 22 actually voted (turnout 25.2%). Among the voters, 23% had an MMSE score of less than 12; 58% of abstentions were procedure-related. Discussion: In our study, some inpatients did not vote as a result of procedural issues. When patients with severe cognitive impairment vote, there is a potential risk of vote diversion. Voting procedures should be improved to give inpatients easier access to the ballot while protecting them from the risk of fraud.

Le vote des sujets ayant des altérations des fonctions cognitives : aspects législatifs et éthiques

In democratic countries, cognitively impaired persons are a substantial and growing group of citizens. Most of them are citizens with dementia. In dementia, cognitive impairment induces a loss of some capacities, resulting in vulnerability and increased need for assistance. Voting by cognitively impaired persons raises any questions about the integrity of the electoral process, the risk of fraud and the respect of their citizenship. In France, the law is not definite about the voting of cognitively impaired persons. An objective assessment for voting capacity may be useful both for professionals in charge of voting organisation and for guardianship judge in order to help him in his decision to remove or keep the voting right of persons placed under guardianship. Assessing the reality of voting by cognitively impaired citizens is necessary to advance respect for their right to vote.

Conséquences de la substitution de l'indinavir par l'abacavir chez un patient infecté par le VIH en succès thérapeutique

Resume Introduction La simplication therapeutique d’une tritherapie antiretrovirale chez les patients infectes par le VIH est possible, mais le succes virologique peut etre compromis par l’apparition de virus resistants. Observation Chez un patient ayant une tritherapie antiretrovirale efficace, l’existence d’une aggravation de la fonction renale a fait remplacer l’indinavir par l’abacavir. Huit semaines apres ce changement, il y a eu remontee de la charge virale, avec apparition d’un virus mute resistant a tous les analogues nucleosidiques. Commentaires Notre cas illustre le danger de l’allegement d’une tritherapie antiretrovirale composee uniquement d’association d’analogues nucleosidiques, chez un patient non naif d’analogues nucleosiques en “succes” virologique, l’exposant ainsi au risque d’emergence de virus mute.

Fracture du sacrum par insuffisance osseuse chez le sujet âgé: à propos de 14 observations

We report a series of 14 elderly patients with sacral insufficiency fractures of the sacrum. All patients presented with pain in low back, pelvis or lower limb which was often misleading. Bone scintigraphy was diagnostic in all the patients. Outcome was favourable in all the cases.

Vascularite systémique associée au virus de l'immunodéficience humaine: à propos d'une observation

We report a case of systemic vasculitis associated with HIV infection. This vasculitis could be classified as PAN like involving peripheral nerve, intestine, skin and joints.