Urinary Antigen Detection Research Articles

Legionnaires' disease in Europe 2000-2002.

Each year, countries that participate in the European Surveillance Scheme for Travel Associated Legionnaires' Disease (EWGLINET) are requested to complete a set of standardized reporting forms that provide epidemiological and microbiological information on the total number of cases (non-travel as well as travel-related cases) detected in their country. Trends at the national and aggregated European level have been analysed for 2000-2002. For this period, 10,322 cases of Legionnaires' disease were reported and national infection rates ranged from 0 to 34.1 cases per million population. A total of 189 outbreaks were associated with nosocomial infection, community exposure or travel. The upward trend in diagnosis through the urinary antigen detection test has resulted in a higher ascertainment of cases in many countries. However, the decline in diagnosis by culture of the organism is likely to severely hamper outbreak investigations in the future if fewer clinical isolates are available for matching with environmental isolates. This important data-set has been used for studying the effectiveness of surveillance and legionella control and prevention programmes within Europe.

Problematiche diagnostiche nelle infezioni sostenute da Legionella pneumophila

The introduction of the research of Legionella antigen in urine has significantly speeded up the diagnosis of Legionella pneumophila infections but has decreased the number of respiratory samples submitted for coltural examination. In 2001 respiratory samples were submitted to our laboratory only from 7% of patients for which antigen detection in urine was requested. Such a percentage decreased to 4% in 2002 and to 2.5% in 2003. For 2 of 14 patients tested in 2002, legionellosis diagnosis could not be confirmed since urine antigen detection provided weak positive values and either respiratory samples for direct isolation of L. pneumophila or blood samples for specific serology tests were lacking.We believe that even if urine antigen detection test is a very useful quick test, it cannot be considered as the only diagnostic tool in Legionella spp. infections.

Evaluation of a standardized F1 capsular antigen capture ELISA test kit for the rapid diagnosis of plague

Rapid detection of soluble F1 capsular antigen in serum, bubo fluid or urine of patients proved to be a valuable tool in the presumptive diagnosis of plague. We evaluated a F1 capsular antigen capture ELISA resembling a commercially available test kit. The minimal detectable concentration was 4 ng/ml. The specificity was 100% when investigating 47 sera from healthy Malagasy subjects and 98.4% when 365 sera from German blood donors were studied. Sensitivity was determined on sera ( n=11) and buboes ( n=18) from bacteriologically confirmed Malagasy plague patients. Sensitivity was 90.1% for serum and 100% for buboes. A standardized F1 capsular antigen capture ELISA test kit might be well suited for the early detection of plague particularly in non-endemic areas where clinical microbiological laboratories have only limited access to alternative techniques for rapid identification of Yersinia pestis.

Severe Peripheral Neuropathy With Areflexic and Flaccid Quadriplegia Complicating Legionnaires' Disease in an Adult Patient

Severe Peripheral Neuropathy With Areflexic and Flaccid Quadriplegia Complicating Legionnaires' Disease in an Adult Patient

RAPID DIAGNOSIS OF TYPHOID FEVER BY ENZYME-LINKED IMMUNOSORBENT ASSAY DETECTION OF SALMONELLA SEROTYPE TYPHI ANTIGENS IN URINE

We developed and evaluated an enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies to capture somatic antigen 9 (O9), flagellar antigen d (Hd), and the Vi capsular polysaccharide antigen (Vi) from the urine of persons with and without typhoid fever. Sequential urine samples were collected from 44 patients with blood culture-confirmed typhoid fever and from two control groups. The first control group included patients with brucellosis (n = 12) and those with clinically diagnosed, non-typhoid, acute, febrile illness (n = 27). The second control group was a sample of healthy volunteer laboratory workers (n = 11). When assessed relative to date of fever onset, sensitivity was highest during the first week for all three antigens: Vi was detected in the urine of nine (100%) patients, O9 in 4 (44%) patients, and Hd in 4 (44%) patients. Sequential testing of two urine samples from the same patient improved test sensitivity. Combined testing for Vi with O9 and Hd produced a trend towards increased sensitivity without compromising specificity. The specificity for Vi exceeded 90% when assessed among both febrile and healthy control subjects, but was only 25% when assessed among patients with brucellosis. Detection of urinary Vi antigen with this ELISA shows promise for the diagnosis of typhoid fever, particularly when used within the first week after fever onset. However, positive reactions for Vi antigen in patients with brucellosis must be understood before urinary Vi antigen detection can be developed further as a useful rapid diagnostic test.

European Guidelines for Control and Prevention of Travel Associated Legionnaires' Disease: the Italian experience.

In Italy, 35 clusters of travel associated Legionnaires' disease were identified from July 2002, when the European Guidelines for Control and Prevention of Travel Associated Legionnaires' Disease have been adopted by the EWGLINET network, to October 2003. Eight per cent (28.6%) would not have been identified without the network. The clusters detected were small, ranging from 2 cases to a maximum of 6. All clusters involved 5 camping sites and 30 hotels/residences, and an overall of 87 patients. The diagnosis was confirmed in 92.0% of the cases and mainly performed by urinary antigen detection (84.7%). A clinical isolate was available only in one case. Following environmental investigations, samples were collected for all the 35 clusters from the water system, and Legionella pneumophila was found in 23 occasions (65.7%). In 15 resorts out of 35, investigations were already in progress at the time of EWGLI cluster notification, since in Italy full environmental investigation is performed even after notification of a single case. Control measures were implemented in all accommodation sites at risk and one hotel only was closed. In all the 35 clusters, reports were completed and sent on time, highlighting that it is possible to comply with the procedures requested by the European Guidelines.

Evaluation of Streptococcus pneumoniae urinary antigen test in healthy children with nasopharyngeal pneumococcal carriage

We evaluated the influence of colonization with pneumococci on the results of Streptococcus pneumoniae urinary antigen detection assay by testing 23 healthy children aged 1-3 years in one nursery. Nasopharyngeal swab specimens for culture and urine samples for antigen detection test were obtained. 7 of 12 children who were nasopharyngeal carriers of pneumococci had a positive result of the urine antigen test. 3 of 11 children without pneumococci in the nasopharynx also had a positive result of the urine antigen test, who were diagnosed as having acute pneumonia within one month before this study. Thus we found that 58.3% of the children with pneumococcal carriage and 27.3% of non-carriers had false-positive test results. This test is not likely to be useful for diagnosing the etiology of childhood acute pneumococcal pneumonia.

An outbreak of legionellosis in a nursery

We experienced an outbreak of legionellosis in infants for the first time in Japan. In Fukushima Prefecture Wakamatsu Nursery, the patients who had respiratory symptoms of cough, wheeze and fever appeared one after another from the middle of June, 2002. We suspected that an outbreak of legionellosis had occurred and then carried out urinary antigen detection of Legionella pneumophila. As a result, 8 patients were positive. They consisted of 5 boys and 3 girls, and ranged in age from 11 months to 1 year 10 months. Underlying disease was observed in one patient, and 6 patients were hospitalized. All 8 patients had rhinorrhea, cough, fever and 7 patients had wheeze. The average duration of cough was 9.9 days and that of fever was 4.5 days. In the admitted 6 patients, WBC ranged in count from 7,500/microliter to 15,300/microliter and CRP ranged from 0.2 mg/dl to 2.5 mg/dl. Chest X-rays showed infiltrative shadows (right lower lobe, left lower lobe) in 2 patients. With regard to the treatment, macrolide or tetracycline antibiotics were administered in 4 of 8 patients, and beta-lactams were administered in others. Water samples were obtained from 12 locations at the nursery, including the shower head of the bathroom, the bathtub, the taps, the laundry and so on. But cultures of water samples failed to grow legionella. We suspected that the source of infection was the humidifiers or the nebulizer used for disinfection. Through this outbreak, it became obvious that the mild case of legionellosis really existed. Furthermore, we suggested that it was possible for the patient with mild legionellosis to cure without administration of macrolide or tetracycline antibiotics.

Usefulness of a new fast technique for detection of pneumococcal antigen in the diagnosis of community pneumonia

With the objective of analyzing the usefulness of a new technique of fast detection of pneumococcal antigen in urine (Binax NOW Streptococcus pneumoniae urinary antigen test) 163 community pneumonia episodes were reviewed. The test was positive in 30 cases, and gave rise to therapeutic implications in 12 patients. The global sensitivity was 57%, being superior in patients with HIV infection (70%), and the specificity was 91.6%. In 16 episodes it was the only diagnostic test of pneumococcal infection. The determination of pneumococcal antigen through this technique is a useful tool for the diagnosis of community pneumonia, mainly due its high specificity.

KAtex Test for the Detection of Urinary Antigens in Visceral Leishmaniasis Patients of Nepal

The rapid detection of parasitic antigens in body fluid including urine by immunological tests such asKAtex has been a valuable addition to clinical medicine. Existing method of microscopic bone-marrowexamination and immunological test for antigen –enzyme-linked immunosorbent assay (ELISA) test forvisceral leishmaniasis antigen are difficult to perform in the field, and this has limited use in rural areas ofendemic countries like Nepal. In this study we have tested 276 urine samples from visceral leishmaniasispatients from different endemic areas of Nepal. Sixty-seven patients (24.3%) were found KAtex positive.The clinical picture of these patients was compared with the KAtex test and additional laboratory findings,knowledge, attitude and behaviour were assessed. High rate of KAtex positive (97.4%) was found in bonemarrow confirmed patients with high degrees of sensitivity and specificity. Hence the study confirmed thatthe KAtex test is suitable for the confirmation of suspected cases in the field and hospital where bonemarrowfacilities are limited or where there is a lack of trained manpower as well as microscopic diagnosisis not available.ORIGINAL ARTICLE Journal of Nepal Medical Association 2003; 42: 191-195Sherchand J B*, Shah S N*, Hommel M**Key Words: Rapid diagnostic test, urinary antigen, visceral leishmaniasis, Nepal.

Travel associated legionnaires' disease in Europe in 2000 and 2001.

The European Surveillance Scheme for Travel Associated Legionnaires' Disease (EWGLINET) was notified of 360 cases in 2000 and 481 cases in 2001, the highest number reported since 1987. This increase reflects enhanced surveillance activities, especially in the Netherlands, France and Italy, mainly through urinary antigen detection test (78% of cases in 2001). The median delay in reporting to the scheme fell to under 30 days, at the cost of some loss of information on the outcomes of illness. In 2000, 28 clusters were detected compared to 72 in 2001, most of this rise resulting from a change in the definition of clusters. In 2000 and 2001, 55 and 140 environmental investigations were reported respectively.

Clinical utility of urinary antigen detection for diagnosis of community-acquired, travel-associated, and nosocomial legionnaires' disease.

The clinical utility of Legionella urinary antigen assays for the diagnosis of Legionnaires' disease was assessed by using samples from 317 culture-proven cases. The sensitivities of the Binax enzyme immunoassay (EIA) and Biotest EIA were found to be 93.7 and 94.4% for travel-associated infection and 86.5 and 76.0% for community-acquired infection but only 44.2 and 45.7% for nosocomially acquired infection, respectively.

Factors related to persistence of Legionella urinary antigen excretion in patients with legionnaires' disease.

The aim of this prospective study was to compare patient characteristics, clinical data, and evolution of Legionella pneumophila pneumonia according to the duration of Legionella urinary antigen excretion. Urine samples from 61 patients with Legionella pneumonia diagnosed by detection of urinary antigen were obtained periodically until urinary antigen could no longer be detected. Cases were divided into two groups based on the duration of urinary antigen excretion: group I (46 patients, <60 days) and group II (15 patients, >or=60 days). Groups were compared for patient characteristics, clinical data, and evolution of pneumonia. Antigen excretion >or=60 days was observed significantly more frequently in immunosuppressed patients ( P=0.001) in whom the time to apyrexia was >72 h ( P=0.002), although only the time to apyrexia remained significant on multivariate analysis ( P=0.006). In conclusion, the duration of Legionella urinary antigen excretion was <60 days in most patients but was longer in immunosuppressed patients with a longer time to defervescence of fever.

A Casuistic Immunologic Response in Primary and Repeated Chlamydophila pneumoniae Infections in an Immunocompetent Individual

<h2>Abstract</h2> We report the first culture proven case of <i>Legionella</i> pneumonia in a HIV-positive patient in Italy. The laboratory diagnosis was obtained by isolation of <i>Legionella pneumophila</i> serogroup 1, serology, urinary antigen detection and PCR. Culture first allowed diagnosis of the infection, that probably would have been unrecognized. Since Legionellosis in HIV-positive patients with respiratory symptoms is rare and difficult to confirm, we strongly suggest that all available laboratory tests, and particularly culture, should be performed. A review of literature on culture proven cases is also provided.

Culture Proven Legionella Pneumophila Pneumonia in a HIV-infected Patient: Case Report and Review

We report the first culture proven case of Legionella pneumonia in a HIV-positive patient in Italy. The laboratory diagnosis was obtained by isolation of Legionella pneumophila serogroup 1, serology, urinary antigen detection and PCR. Culture first allowed diagnosis of the infection, that probably would have been unrecognized. Since Legionellosis in HIV-positive patients with respiratory symptoms is rare and difficult to confirm, we strongly suggest that all available laboratory tests, and particularly culture, should be performed. A review of literature on culture proven cases is also provided.

PNEUMOLYSIN IN URINE: A RAPID ANTIGEN DETECTION METHOD TO DIAGNOSE PNEUMOCOCCAL PNEUMONIA IN CHILDREN

Purpose: Etiological diagnosis of pneumococcal pneumonia is difficult in small children in whom blood culture cannot be done or who have already been started on antibiotics. A simple technique which can be applied at the bedside or in the outpatient department may help in obviating this problem. Detection of pneumolysin, a product of invasive pneumococci is being exploited as a diagnostic tool. Methods: An attempt was made to detect this protein in urine of seventy children, clinically suspected and radiologically diagnosed cases of pneumonia. Seventy age and sex matched controls were included in the study. Purified pneumolysin was prepared from clinical isolates of invasive pneumococcal infections. This was used to raise polyclonal antisera in rabbits. The antisera was used to sensitise Cowan 1 Staphylococcus aureus (CoA). A slide agglutination was performed with 25 µL urine and equal quantity of the reagent. Results: Results were compared with CoA reagent sensitised with antisera raised against a genetically derived pneumolysoid and capsular polysaccharide for antigen detection in the urine. Pneumolysin could be detected in 42.9% (30/70) urine samples from cases with pneumonia by the genetically derived antigen and in 37.1% samples by the in house prepared antigen, in contrast to 2.1% in healthy controls and 4.2% in children with infections other than pneumonia. The result was statistically significant. Detection of pneumolysin was slightly better than detection of capsular polysaccharide antigen in urine although the result was not statistically significant. Blood culture proved to be positive in only 29.5% cases. Conclusions: Pneumolysin detection in urine showed promising results and was found to be simple and rapid. It will help in quickening the diagnosis of pneumococcal pneumonia.

Intensified microbiological investigations in adult patients admitted to hospital with lower respiratory tract infections

The objective of this study was to investigate the diagnostic yield of a programme with intensified microbiological investigations in immunocompetent adult patients with lower respiratory tract infections (LRTI). Patients in the study group were included prospectively and consecutively from September 1st 1997 to May 31st 1998 and were compared with a control group from the preceding year. A total of 67 adult patients were included in the study group and they were compared with 122 adult patients in the control group. The study group underwent fibre-optic bronchoscopy (FOB) with bronchoalveolar lavage (BAL). Only 7% in the historic control group were discharged with an aetiological diagnosis of their infections, while the diagnostic yield in the study group increased to 51% of patients. In the study group the presence of new infiltrates on chest X-ray increased the detection of a microbiological aetiology from 37% with no infiltrates to 62% with infiltrates and recent antibiotic therapy reduced the detection of a microbiological cause of infection from 61% in 36 patients who had not received antibiotic therapy to 39% in 31 patients who had received recent antibiotic therapy prior to microbiological sampling. Patients in the study group with known aetiology had higher values of inflammatory markers than patients with unknown aetiology. For Streptococcus pneumoniae infection culture and urine antigen detection were complimentary depending on recent antibiotic therapy since seven of eight culture-positive patients had not received antibiotic therapy within 72 h prior to investigation, while all four patients positive for urine antigens from S. pneumoniae had received antibiotic therapy within 72 h of urine sampling. In conclusion intensified microbiologic investigations increase the diagnostic yield from 7% to 51% of patients in the study group with an aetiologic diagnosis. Routine FOB with BAL had no apparent effect on clinical outcome and seems only justified in selected patients with severe LRTI with infiltrates on chest X-ray and signs of severe inflammation where a high diagnostic yield is achieved.

Control of nosocomial Legionnaires' disease by keeping the circulating hot water temperature above 55°C: experience from a 10-year surveillance programme in a district general hospital

After a nosocomial outbreak of Legionnaires' disease in a 450-bed district general hospital in 1991, the circulating hot water temperature was kept above 55°C as the sole control measure. From 1991 to 2000, all cases of nosocomial pneumonia were clinically monitored and tested for Legionella pneumophila serogroup 1 by serology or urinary antigen detection. Water samples from peripheral tap sites were cultured for Legionella spp. twice a year. An infection with L. pneumophila serogroup 1 was diagnosed in four out of 366 (1.1%) patients treated for nosocomial pneumonia, representing one case per 26000 admissions. All patients were cured without complications. L. pneumophila serogroup 1 was isolated in 30 of 251 (12%) cultured hospital water samples during the monitoring period. We conclude that control of nosocomial Legionnaires' disease in a primary referral hospital is possible by keeping the circulating hospital hot water temperature above 55°C, together with careful clinical surveillance. Complete eradication of Legionella spp. from the hot water system does not seem necessary.

Prevención y tratamiento de la neumonía adquirida en la comunidad en pacientes adultos: Un enfoque para la atención primaria

Community-acquired pneumonia is a frequent cause of morbidity, hospitalization and death especially among patients with risk factors. Several agents can provoke this condition and their relevance change according to specific epidemiological exposures, time of the year and comorbidity, being Streptococcus pneumoniae the most frequent etiological agent followed by Mycoplasma pneumoniae, Chlamydia pneumoniae, respiratory viruses and Haemophilus influenzae. Management requires proper identification of the most vulnerable patients and prompt admittance and X-ray confirmation to analyze extension, complications or differential diagnosis. Etiological studies are limited by the low sensitivity and specificity of the sputum Gram stain, the invasive nature of some techniques or the high cost of a comprehensive study. Nonetheless, etiological studies are relevant on severe cases, immunosuppressed patients or those without response to an empirical treatment. New diagnostic tests include serological studies for atypical pathogens, direct detection of viral agents or pneumococcal antigens on sputum samples and Legionella pneumophila serotype 1 antigen detection in urine. Penicillin resistant pneumococcal (PRP) isolates associated to pneumonia or bacteremia as well as isolates with resistance to third generation cefalasporins or macrolides are still infrequently observed among adult patients in Chile. Notwithstanding, worldwide experience indicates that patients affected by PRP isolates and treated with penicillin do not evolve with a higher risk for treatment failure, except for those cases where the MIC for penicillin is equal or higher than 4 µg/mL

Toxicidad pulmonar por talidomida

Although the side effects of thalidomide are well known, lung toxicity has not been reported. We describe the case of a 65-year-old man with multiple myeloma (IgG kappa) in stage IA who, on the thirty-seventh day of treatment with thalidomide, developed acute coughing, general malaise, dyspnea at rest and sudoresis. Blood pressure was 90/60 mm Hg and temperature was normal. An interstitial and alveolar pattern was visible on the right side of a chest film and arterial blood gases indicated partial respiratory insufficiency (pH 7.40, PaCO2 40 mmHg, PaO2 47 mmHg). Blood analysis showed alterations expected for multiple myeloma and microbiology was negative (sputum and blood cultures and urinary antigen detection for Streptococcus pneumoniae and Legionella pneumophila). After thalidomide was withdrawn and oxygen and intravenous corticoids were administered, outcome was good. A chest film 4 days later was normal and arterial blood gases showed that respiratory insufficiency had disappeared. We conclude that severe lung toxicity should be included among the potential adverse effects of thalidomide.