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PubMed2004

Non-adherence to medications following pediatric liver transplantation.

Non-adherence to medications is a leading cause of organ loss and morbidity in children and adolescents who had a liver transplant. Yet there are very few published studies about ways to detect whether patients are taking their medications or not, and about treatment options to improve adherence. The Pediatric Liver/Liver Transplant Program at Mount Sinai developed clinical and research programs that evaluate adherence. We review initial results from these programs. Clinic patients participate in an adherence-monitoring program that involves standardized assessments by patients, parents, clinicians, and routine examinations of medication blood levels. A research program adds an electronic monitoring device (MEMS-caps, AARDEX/APREX, Switzerland) and examines the use of azathioprine metabolites as predictors for non-adherence. Patients receive a thorough psychosocial evaluation to identify potential risk factors for non-adherence. Preliminary results indicate that an objective adherence detection method has to be incorporated into practice if non-adherence is to be reliably detected (clinicians' impressions and patients' reports are not sufficient). A risk factor for non-adherence, post-traumatic stress disorder, emerges as a potential target for intervention. It is possible to integrate a formal mechanism to assess adherence into the work of a liver/liver transplant clinic. We hope that the presented program will inspire clinicians in the community and other programs to regard the assessment and improvement of adherence to medications as an important goal in the management of children who had a transplant.

Azathioprine↗
PubMed2006

Robust human detection within a highly dynamic aquatic environment in real time.

This paper presents a real-time foreground detection method for monitoring swimming activities at an outdoor swimming pool. Robust performance and high accuracy of detecting objects-of-interest are two central issues of concern. Therefore, in this paper, a considerable amount of attention has been placed on the following aspects: 1) to establish a better method of modeling aquatic background, which exhibitis dynamic characteristics with random spatial movements, and 2) to establish a method of enhancing the visibility of the foreground by removing specular reflection at nighttime. First, the development of a new background modeling method is reported. In the proposed approach, the background is modeled as a composition of homogeneous blob movements. With an implementation of a spatial searching process, the proposed method shows capability in associating and distinguishing movements caused by the background. Hence, this contributes to better performance in foreground detection. On the issue of enhancing the visibility of the foreground, a decision-based filtering scheme is proposed as a preprocessing step. A defined concept term, fluctuation measure, is defined for classifying each pixel to be one of the predefined types. This has allowed suitable spatial or spatiotemporal filters to be applied accordingly for color the compensation step. All of these developments are evaluated by testing live on a busy Olympic-size outdoor public swimming pool. Both qualitative and quantitative evaluations are reported. This provides a comprehensive study of the system.

Algorithms↗
PubMed2005

Body mass index as a predictor of prostate cancer: development versus detection on biopsy.

OBJECTIVES: To determine whether obesity is biologically associated with an increased risk of prostate cancer development, especially aggressive disease and to explore whether a bias may exist in our ability to detect these cancers in obese patients. METHODS: We evaluated the association of body mass index (BMI) with prostate cancer, biopsy Gleason sum, and amount of cancer using logistic and linear regression analyses adjusting for age at biopsy, race, prostate-specific antigen level, digital rectal examination findings, and prostate volume among 787 consecutive men undergoing prostate biopsy between 1998 and 2002 at an equal-access medical center. RESULTS: Men with a higher BMI were younger (P < 0.001), had lower prostate-specific antigen concentrations (P = 0.02), fewer abnormal digital rectal examination findings (P = 0.02), and larger prostate volumes (P < 0.001). After adjusting for age, no overall association was found between BMI and the odds of being diagnosed with cancer (P trend = 0.89), although overweight and mild obesity were inversely associated with the diagnosis of cancer. After multivariable adjustment, a higher BMI was associated with an increased odds of being diagnosed with prostate cancer (P trend = 0.007). Among men diagnosed with cancer, and after multivariable adjustment, a higher BMI was associated with a similar percentage of biopsy tissue with cancer (P trend = 0.23), but with greater odds of a high Gleason sum (P trend = 0.004). CONCLUSIONS: After taking into account the clinical characteristics that influence the likelihood of finding an existent cancer, a higher BMI was positively associated with being diagnosed with prostate cancer. Also, among the men with cancer, a higher BMI increased the odds of high-grade disease. These findings suggest that obesity may be biologically associated with prostate cancer development and, in particular, with high-grade disease.

Aged↗
PubMed1992

Primary depth cues and background pattern in the portrayal of slant.

A rectangularity postulate has been used in algorithms for the purpose of interpreting two-dimensional representations of rectilinear objects. This rectangularity postulate may affect the perception of true surfaces. In this study, rectangular surfaces and trapezoidal surfaces--the latter simulating the horizontal slant-in-depth of the rectangular surfaces--were viewed under static-monocular, moving-monocular, and static-binocular conditions, both with and without a background pattern. The static-binocular condition elicited the greatest number of accurate responses. The moving-monocular condition did not elicit significantly more accurate responses than the static-monocular viewing condition did. The effect of background pattern was insignificant. These results were unexpected in terms of ecological validity and (regarding moving-monocular viewing) because of the importance of the role of relative visual motion in the detection of object motion. However, the results are consistent with the perception of depth separation of two discrete objects.

Adult↗
PubMed1993

Precision of dual-energy x-ray absorptiometry: development of quality control rules and their application in longitudinal studies.

In research settings, longitudinal measurements of bone mineral density have become an integral part of the assessment of patients with metabolic skeletal disorders. To adequately utilize longitudinal measures, confidence in the long-term precision of the measurement technique must be very high. Dual-energy x-ray absorptiometry (DXA) has become commonly utilized in this context, and to better understand its long-term precision and to develop quality assurance protocols for its use, we examined the performance of eight DXA machines over a 3 year period. Anthropomorphic spine phantoms were measured frequently on each machine during the period of observation, and precision was estimated from the consistency of these determinations. Overall precision was excellent (mean longitudinal coefficient of variation, 0.4%). Nevertheless, by using a series of objective quality control criteria, small alterations in the performance of each machine were identified (mean number of changes, 4.6 in 3 years; mean magnitude, 0.0039 g/cm2, or 0.4%). The cumulative effects of those changes were sufficient to cause a significant (albeit minor) change in the regression slopes (phantom mineral density versus time) of most machines. The same quality control rules were also used to quantitate the magnitude of change and to adjust retrospectively machine performance during the period of observation, such that alterations were minimal and regression slopes were not significantly different from zero. Although the precision of DXA is excellent, alterations in machine function must be anticipated during longitudinal use. The development of quality control protocols provides the means to detect change objectively and to adjust for alterations in performance during the course of longitudinal evaluations.

Absorptiometry, Photon↗
PubMed2002

Pilot study of testicular cancer awareness and testicular self-examination in men attending two South London general practices.

BACKGROUND: Testicular cancer (TC) awareness and testicular self-examination (TSE) have never been evaluated adequately in UK general practice. TC has a 96% cure rate if detected early. OBJECTIVES: Our aim was to estimate awareness of TC and practice of TSE in a general practice population. METHOD: A cross-sectional questionnaire survey was carried out in 250 consecutive male attenders aged 18-50 years in two general practices, one inner city, and one suburban. After obtaining informed consent, male patients in the waiting room were asked to complete a brief confidential questionnaire about TC and TSE. RESULTS: The response rate was 81%. Mean age was 32 years (range 18-50). Seventy-five per cent of responders described themselves as white, 12% Asian, 6% black and 7% other ethnic groups. Ninety-one per cent were aware of TC but only 26% knew both the age group most affected (25-34 years) and that TC can be curable if detected early. Although 49% of responders had carried out TSE in the past year, only 22% were practising according to recommendations: feeling for lumps at least monthly. TSE was associated with age >35 years, white ethnicity, knowing someone with TC, having attended a Men's Health Clinic and having heard of the 'Everyman' TC awareness campaign. CONCLUSION: Although awareness of TC in this GP population was reasonable, less than half were practising TSE. Further public health campaigns may be needed.

Adolescent↗
PubMed1998

Incorporation of a set enumeration trees-based classifier into a hybrid computer-assisted diagnosis scheme for mass detection.

RATIONALE AND OBJECTIVES: The authors evaluated whether a hybrid classifier of two independent computer-aided diagnosis (CAD) schemes, the set enumeration (SE) trees approach and an artificial neural network (ANN), could improve the detection of masses on digitized mammograms. The potential benefits resulting from the interpretability of the SE trees model was also explored. MATERIALS AND METHODS: Two hundred thirty verified mass regions and 230 negative but suspicious regions were randomly selected from 618 digitized mammograms. Each region was represented by a 24-parameter feature vector. These features were used as input data for the SE trees and ANN-based schemes. After the positive and negative regions were randomly segmented into five exclusive partitions, a fivefold cross-validation method was applied to evaluate and compare the performance of the SE trees, ANN, and hybrid system in the identification of masses. RESULTS: The performance of the SE trees approach was comparable to that of the ANN. The average area under the receiver operating characteristic (ROC) curves for all five partitions was 0.88 (standard deviation, 0.04). Owing to the relatively low correlation between the region-based results of the SE trees and ANN methods, the hybrid classifier yielded a significantly improved performance, with an area under the ROC curve of 0.94 (standard deviation, 0.02; P < .05). CONCLUSION: The hybrid CAD scheme significantly improved performance. The amenability of the SE trees models to interpretation may aid in the assessment of the importance of specific features.

Artificial Intelligence↗
PubMed2000

Urological cancers: do early detection strategies exist?

OBJECTIVE: To determine the perceptions of healthcare professionals and the general public about the symptoms, diagnosis and available treatment of urological cancers, and thus the perceived value of screening for their early detection. SUBJECTS AND METHODS: Two questionnaires were developed, based on semi-structured interviews, and distributed to 288 healthcare professionals, comprising 182 general practitioners (GPs), 56 practice nurses and 50 urology nurses, and to 250 members of the general public in three different socio-economic groups. The questionnaires asked about the symptoms, diagnosis and treatment of prostate, bladder and testicular cancer, and whether the respondents considered that screening for these cancers would be useful in ameliorating morbidity or death from these diseases. RESULTS: The response rate was very poor (13 of the GPs, 7%; 34 of the nurses, 32%; and 58 members of the general public, 23%). This severely limited the interpretation of the results, but the responses highlighted areas which need addressing. Obvious symptoms were well understood by all the groups but less well-known symptoms could be missed. No GP supported screening for prostate cancer and only seven of the GPs believed in teaching testicular self-examination, but practice nurses were considerably more active in all aspects of patient education. The general public felt that they needed more information to make decisions about urological cancers, although there was a general feeling that 'screening saved lives'. CONCLUSION: This survey showed that no healthcare professional seems to have a clearly defined role in informing potential patients about screening. The general public, who seem to perceive from the media that early detection is beneficial, are confused by the lack of clarity about policies for urological cancers.

Adolescent↗
PubMedDate not supplied

[Clinical complications in a series of patients with anticardiolipin antibodies].

An analysis was made of clinical complications, determined with objective methods, in 68 patients at the University Clinic of Navarra with the clinical suspicion of antiphospholipid syndrome (APS) and presence of anticardiolipin antibodies (ACA). Patients with IgG higher than 23 GPL were considered for the study. The most prevalent pathology was thrombosis: venous thrombosis (42.6%) and arterial thrombosis (22%). Other complications were abortions (23.8% of the 42 women) and thrombocytopenia (12.1%). With respect to the localisation of venous thrombosis, predominance corresponded to lower extremities (51.7%), followed by superficial thrombophlebitis (27.5%) and pulmonary thromboembolism (20.6%). Among the arterial complications, the most frequent were cerebrovascular disease (86.6 %) and coronary disease (13.4%). There was no correlation between the presence of high values of ACA and the prevalence or severity of clinical manifestations. In the series of patients with ACA IgG>23 GPL, we appreciated a high percentage of venous and arterial thrombosis detected with objective methods. The presence of ACA constitutes a prothrombotic risk factor

Adult↗
PubMed1976

[Methods of detecting the agent of melioidosis in objects of the external environment and other material].

On the basis of literature data and personal investigations the authors elaborated a scheme of detection of the causative agent of melioidosis in the objects of external environment, including fluorescent microscopy of crude material, seeding on meat-peptone agar with crystal violet, seeding material treated with penicillin on fluid medium with subsequent transfer on solid Levin medium and infection of animals, seeding on a medium with beta-alanine and neonmycin and infection of sensitive animals with crude material.

Animals↗
PubMed2003

Using gray-scale and two different techniques of color Doppler sonography to detect prostate cancer.

OBJECTIVES: To correlate the findings of prostate color Doppler sonography (CDS) with those of site-specific transrectal ultrasound-guided core biopsy; to evaluate the significance of two different color presets in detecting prostate cancer compared with gray-scale transrectal ultrasonography; and to compare the accuracy of conventional gray-scale transrectal ultrasound (CGS)-guided biopsy with CDS-guided biopsy. METHODS: Seventy patients were enrolled in this prospective study. CDS was performed before biopsy. Two color presets were used: CDS-1 (high sensitivity) and CDS-2 (high specificity). The color flow was graded on a scale from 0 to 2+. At the completion of the color grading, color maps were constructed. In each case, CDS-guided biopsy was performed followed by CGS-guided biopsy (six sextant biopsies and focal lesional biopsies). RESULTS: The cancer detection rate was 33%, 31%, and 27% for CGS-guided biopsy, CDS-1, and CDS-2, respectively. CDS-1 was more sensitive than CDS-2 (81% versus 60%) but both presets had similar specificities (79% versus 82%). CGS-guided biopsy yielded a sensitivity of 90%, a specificity of 38%, and a positive and negative predictive value of 34% and 83%, respectively. A biopsy strategy combining hypoechoicity with increased color flow increased the specificity to 97%, positive predictive value to 68%, and negative predictive value to 84%, but its sensitivity was low (18%). CONCLUSIONS: Our experience suggests that low-velocity, high-sensitivity color is superior to all other CDS settings. The presence of focal peripheral zone hypervascularity at CDS is associated with a high likelihood of prostate cancer. However, only a combination of CDS guidance with six sextant biopsies may achieve maximal sensitivity and specificity.

Aged↗
PubMed2006

Cerebral palsy and the application of the international criteria for acute intrapartum hypoxia.

OBJECTIVE: To apply objective criteria for the identification of acute intrapartum hypoxia in a cohort of cerebral palsy cases and to identify other cerebral palsy-related pathologies. METHODS: A cohort of all 235 neonates with cerebral palsy from a single Australian tertiary care center born between 1986 and 2003. Cases were identified from the South Australian Cerebral Palsy Register. Maternal and pediatric case notes were audited with application of the 2003 American College of Obstetricians and Gynecologists/American Academy of Pediatrics criteria to identify acute intrapartum hypoxia. RESULTS: Data were available for analysis in 213 cases (91%). Major antenatal or pediatric cerebral palsy-related pathologies were identified in 98.1% of all these cases. An isolated acute intrapartum hypoxic event was defined as likely in only 2 of the 46 neonates born at term and none born preterm. Neonatal nucleated red blood cell counts were often high in neonates born preterm and following antenatal pathologies. CONCLUSION: Cerebral palsy was seldom preceded by acute intrapartum hypoxia but antenatal cerebral palsy-related pathologies are often detectable. The objective American College of Obstetricians and Gynecologists/American Academy of Pediatrics criteria are useful to audit cerebral palsy causation and exclude primary intrapartum hypoxia. LEVEL OF EVIDENCE: II-3.

Apgar Score↗
PubMed2004

Vertebral body granuloma of the cervical region after pencil injury.

OBJECTIVE AND IMPORTANCE: Granuloma formation has been reported as a rare complication of pencil lead injury. Insufficient data exist regarding pencil lead injuries of the cervical spine. We present the findings in an 18-year-old male patient with secondary granuloma formation after a penetrating transoral pencil injury. We suggest that imaging characteristics and a detailed history will assist with the diagnosis of such lesions. CLINICAL PRESENTATION AND INTERVENTION: The patient was an 18-year-old man who presented with cervical pain. His history included falling as a child while having a pencil in his mouth. T2-weighted imaging studies documented a 1- x 1-cm enhancing lesion posterior to the vertebral body at the C3 level. The patient underwent a C3 vertebrectomy, and specimens were notable for infection, pencil lead, and granuloma formation. CONCLUSION: In the evaluation of a potential granuloma or mass lesion of the cervical spine in a child or adolescent, the differential diagnosis may include a neoplasm. Although computed tomography is an ideal tool to detect foreign objects, including pencil leads, only awareness of the potential for pencil lead injuries and that pencil lead fragments may remain unrecognized on computed tomographic scans will assist the physician in diagnosing such injuries.

Adolescent↗
PubMed1995

[Diagnosis and treatment of erectile dysfunctions].

OBJECTIVES: Erectile dysfunction (ED) is the most frequent form of male sexual dysfunctions. The incidence is not known. Approximately 10% of men suffer from ED. Aging is concomitted by an exponential increase in the occurrence of erectile dysfunctions. Some groups of men (suffering from diabetes, alcoholism, ICHS, renal diseases) yield several times higher values of their occurrence. In general, ED (formerly impotentio coeundi) can be defined as an inability to achieve erection and maintain it for an appropriately long period enabling sexual intercourse. ETIOPATHOGENESIS: The etiology includes psychological, neurological, arterial, sinusoidal, venous and hormonal factors which participate in erectile function. ED arises predominantly in consequence of impaired haemodynamics of the penis. It develops either due to insufficient blood inflow into the erectile bodies or due to their excessive drainage. The traumatic lesions of penile vessels are less frequent. Drugs and medicaments play a significant role among etiologic factors causing erectile dysfunctions. DIAGNOSIS: No regulations and principles are generally valid in coincidence with examination of patients with erectile dysfunction. The signs of neurologic, hormonal and vascular defects are detected. An objective method of examination of erectile capacity of the penis resides in the monitoring of penile nocturnal tumescensions. The examination of arterial system of the penis provides information on the perfusion pressure and blood flow in the cavernous arteries. The vascular structures of the penis and their functions can be evaluated by means of duplex ultrasonography and flowmetry. The quality to arterial supply to erectile bodies is evaluated by dynamic examination of arteries prior to and after intracavernous application of vasoactive substances. The functional state and size of venous leak from the cavernous bodies are evaluated by dynamic cavernosometry. THERAPY: The application of vasoactive substances meant a significant contribution to the diagnosis establishment and therapy of erectile dysfunctions. They have a common feature which resides in their myorelaxation effect and thus in their ability to induce erection by means of relaxation of the smooth muscles of cavernous bodies. Intracavernous application of vasoactive substances is the mostly spread means of therapy of erectile dysfunction as a whole, frequently with no regard to the etiology. Surgical therapy of vasculogenous impotence is based on knowledge concerning the impact of vascular lesions on the haemodynamics of erectile function of the penis. the revascularisation operations are aimed at the regeneration of normal haemodynamic conditions in the penis. CONCLUSION: Sexual life is currently considered as a proportion of life of individuals. The physicians therefore have to seek ways of how to help the patients who due to acquired erectile dysfunctions are handicapped in the establishment of family harmony and sexual life. (Ref. 31).

Erectile Dysfunction↗
PubMed2000

Intratracheal clenbuterol in the horse: its pharmacological efficacy and analytical detection.

Clenbuterol, a beta2 agonist/antagonist, is the only bronchodilator approved by the US Food and Drug Administration for use in horses. The Association of Racing Commissioners International classifies clenbuterol as a class 3 agent, and, as such, its identification in post-race samples may lead to sanctions. Anecdotal reports suggest that clenbuterol may have been administered by intratracheal (IT) injection to obtain beneficial effects and avoid post-race detection. The objectives of this study were (1) to measure the pharmacological efficacy of IT dose of clenbuterol and (2) to determine the analytical findings in urine in the presence and absence of furosemide. When administered intratracheally (90 microg/horse) to horses suffering from chronic obstructive pulmonary disease (COPD), clenbuterol had effects that were not significantly different from those of saline. In parallel experiments using a behavior chamber, no significant effects of IT clenbuterol on heart rate or spontaneous locomotor activity were observed. Clenbuterol concentrations in the urine were also measured after IT dose in the presence and absence of furosemide. Four horses were administered i.v. furosemide (5 mg/kg), and four horses were administered saline (5 mL). Two hours later, all horses were administrated clenbuterol (IT, 90 microg), and the furosemide-treated horses received a second dose of furosemide (2.5 mg/kg, i.v.). Three hours after clenbuterol dose (1 h after hypothetical 'post-time'), the mean specific gravity of urine samples from furosemide-treated horses was 1.024, well above the 1.010 concentration at which furosemide is considered to interfere with drug detection. There was no interference by furosemide with 'enhanced' ELISA screening of clenbuterol equivalents in extracted and concentrated samples. Similarly, furosemide had no effect on mass spectral identification or quantification of clenbuterol in these samples. These results suggest that the IT dose of clenbuterol (90 microg) is, in pharmacological terms, indistinguishable from the dose of saline, and that, using extracted samples, clenbuterol dose is readily detectable at 3 h after dosing. Furthermore, concomitant dose of furosemide does not interfere with detection or confirmation of clenbuterol.

Administration, Inhalation↗
PubMed1989

[Evaluation of an enzyme immunoassay for the rapid diagnosis of paucibacillary tuberculosis in adults].

The ELISA has been extensively evaluated as a serodiagnostic method for tuberculosis. However, there is scarce information about its application to cases that cannot be diagnosed by microscopic examination: those with closed lesions or undergoing early stages of the disease. Since a reliable serological test might substantially contribute to their prompt detection, the objective of the present study was to determine the diagnostic value of an ELISA applied to adult smear-negative cases of tuberculosis. Sera from 235 patients with active tuberculosis--176 pulmonary and 59 extrapulmonary cases--and 181 control subjects were tested for IgG antibodies to PPD by ELISA. Eleven cases of non tuberculous mycobacterial (MOTT) disease and 33 cases of mycosis were also included in this group. With the adopted cut-off value, 73.9% (105/142) of smear positive and 52.7% (49/93) of smear negative tuberculosis cases, were correctly classified. Particularly in the latter, the test was positive in 55.2% (32/58) of patients with positive cultures for Mycobacterium tuberculosis and in 48.6% (17/35) of patients diagnosed by clinical, radiological and or histopathological findings. No antibody activity was demonstrated in 92.7% of sera from the control population which included 92 healthy volunteers, 32 non tuberculous diseased subjects and 13 household contacts of smear-positive cases. Among those control subjects who were skin tested, ELISA results were not related to the tuberculin reactivity: 93.7% (30/32) of tuberculin negative and 95.2% (40/42) of tuberculin positive healthy individuals had no detectable antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1997

[Medical examination of foreigners entering France: objectives, applications, results].

The health control of the travellers and medical assistance for them and their families is one of the oldest and most fundamental missions of the "Office des migrations internationales" (OMI) as defined by the reglementary treaties of November 1945 and June 1946. More recent reglementations have broadened the competence of the OMI to include certain categories of foreigners who had been exempt from all controls. Finally, the ministerial order of November the 7th 1994 specifies means of the health screening. Medical examinations are carried in various French and foreign institutions. It nowadays has become a consultation aiming at prevention and orientation. The medical examination has three principal objectives: the detection of little known abnormalities; the contact between the medical service of the OMI and regional services in charge of the first check-up; the health education of the examined persons. The clinical and paraclinical results are communicated to the patient who is also informed of the most serious health questions, as well as ways of gaining access to medical care in France; this is done by taking into account all medical parameters and health conditions prevailing in the patient's native country. All detected abnormalities are brought to the attention of the head physician of the OMI who in turn informs the medical inspector of the "Direction départementale des affires sanitaires et sociales" (DDASS) in charge of making sure that the migrant benefits from health and social assistance and receives medical treatment. All pathological results are given to the examined persons in form of a written and confidential report, enabling them to visit a doctor of their choice. A network has thus been built up throughout the various departments involved in the first medical examination and the DDASS has made available for the OMI medical staff listings of public institutions likely to welcome the migrants.

Emigration and Immigration↗
PubMed2002

Interference by rheumatoid factor activity in the detection of antiavian antibodies in pigeon breeders disease.

The assessment of antiavian antibodies is relevant for the study of pigeon breeder's disease; nevertheless, different factors may hamper their accurate detection. The objective of this study was to determine whether an endogenous interfering effect in pigeon breeder's disease might explain the simultaneous presence of IgM, IgG, and IgA antiavian antibodies in high titers as assessed by ELISA. Fifty-nine patients with pigeon breeder's disease, 80 healthy controls, and 47 asymptomatic breeders were studied. To assess possible interfering effects by endogenous immunoglobulins, serum IgG was separated through protein A-Sepharose CL-4B chromatography. Antiavian antibodies were measured in whole and separated samples by ELISA. Since a decline of IgM antiavian antibodies following IgG removal was consistent with a false-positive effect, the causes were studied. High values of IgM, IgG, and IgA antiavian antibodies were found in 47.4% [corrected] of patients with pigeon breeder's disease. An IgM rheumatoid factor activity against IgG was found through ELISA in sera with false-positive IgM antiavian antibodies. Rheumatoid factor binding was confirmed by Western blot. Experimental addition of purified rheumatoid factor to sera with IgG antiavian antibodies replicated the interfering effect. A control group of rheumatoid arthritis with high rheumatoid factor values did not show positive antiavian antibodies tests. No IgG with anti-IgM or anti-IgA activity was found, and the detection of IgA against IgM and IgG was negative. In conclusion, the study of antiavian antibodies might be affected by different immunoassay conditions. An endogenous rheumatoid factor activity produced false-positive IgM results. Other similar interferences warrant a careful evaluation during the serological assessment of pigeon breeder's disease.

Adult↗