Human metapneumovirus in haematopoietic stem cell transplantation recipients: a case series and review of the diagnostic and therapeutic approach.

Human metapneumovirus (hMPV) is a paramyxovirus that causes respiratory tract infections ranging from mild upper airway infection to severe pneumonia. Patients with haematological disease, especially haematopoietic stem cell transplantation (HSCT) recipients, are more likely to develop more severe infections. We describe three cases of hMPV infection in HSCT patients. The most reliable diagnostic procedure for hMPV is multiplex ligation-dependent probe amplification (MLPA) on a nasopharyngeal swab. Sensitivity and specificity of MLPA to detect hMPV is high and time to diagnosis is short. A number of other respiratory pathogens can be tested in one test run. Treatment is mainly supportive and only a few antiviral agents are available for treating paramyxovirus infections. Ribavirin and immunoglobulins were reported to be effective in cases of HSCT patients with hMPV pneumonia but their efficacy has not been studied in randomised trials.

Evaluation of Legionella V-TesT for the detection of Legionella pneumophila antigen in urine samples.

We evaluated a new immunochromatographic assay (Legionella V-TesT, Coris BioConcept, Gembloux, Belgium) for its ability to detect Legionella pneumophila serogroup 1 antigen in urine. Test devices were read at various time points to determine the optimum incubation time regarding performance. The results were compared with those obtained with the BinaxNOW urinary antigen test. The sensitivity and specificity were 82.2% and 98.6%, respectively, for the Legionella V-TesT and 83.9% and 100%, respectively, for the BinaxNOW urinary antigen test after 15 min of incubation. When tests were examined after 60 min, the sensitivity for both tests increased to 91.5%.

Evaluation of the Oxoid Xpect Legionella test kit for detection of Legionella pneumophila serogroup 1 antigen in urine.

We evaluated a new immunochromatographic assay (Oxoid Xpect Legionella test kit) for the ability to detect Legionella pneumophila serogroup 1 antigen in urine. The results were compared with those obtained with the Binax NOW urinary antigen test by following the manufacturers' instructions. The sensitivities and specificities were estimated to be 89 and 100%, respectively, for the Oxoid Xpect Legionella test kit and 86 and 100%, respectively, for the Binax NOW test.

Incidence and completeness of notification of Legionnaires' disease in The Netherlands: covariate capture-recapture analysis acknowledging regional differences.

To estimate incidence and completeness of notification of Legionnaires' disease (LD) in The Netherlands in 2000 and 2001, we performed a capture-recapture analysis using three registers: Notifications, Laboratory results and Hospital admissions. After record-linkage, 373 of the 780 LD patients identified were notified. Ascertained under-notification was 52.2%. Because of expected and observed regional differences in the incidence rate of LD, alternatively to conventional log-linear capture-recapture models, a covariate (region) capture-recapture model, not previously used for estimating infectious disease incidence, was specified and estimated 886 LD patients (95% confidence interval 827-1022). Estimated under-notification was 57.9%. Notified, ascertained and estimated average annual incidence rates of LD were 1.15, 2.42 and 2.77/100 000 inhabitants respectively, with the highest incidence in the southern region of The Netherlands. Covariate capture-recapture analysis acknowledging regional differences of LD incidence appears to reduce bias in the estimated national incidence rate.

[Legionella outbreak in Amsterdam: a cooling tower as the source]. / Legionella-uitbraak in Amsterdam: koeltoren als bron.

During the period 6-28 July 2006, 30 confirmed cases of Legionella infection were identified in Amsterdam, 2 of which were fatal. All had a positive urinary antigen test, by which Legionella pneumophila serogroup I could be demonstrated. Consultations between the parties involved in the control of infectious diseases started on July 7th, as soon as it became clear that there was an outbreak. On July 10th it was established that relatively many of these patients lived in the eastern part of the city centre. After a study of the prevailing winds during the past 3 weeks, the search for installations containing water was started. A cooling tower in the town centre was closed on July 11th by way of precaution. During the following week, this tower was proven to be the source of the outbreak.

[Three patients with pneumonia due to Legionella associated with a sauna, a cooling tower and a caravan in The Netherlands]. / Drie patiënten met Legionella-pneumonie, in verband gebracht met een sauna, een koeltoren en een caravan in Nederland.

In three male patients with lower respiratory disease, aged 51, 32 and 63 years, Legionnaires' disease was diagnosed by urinary antigen test and culture of the respiratory-tract fluid. In the second patient, the bronchoalveolar fluid also contained Streptococcus pneumoniae and Haemophilus influenzae. All three patients recovered after treatment with azithromycin in the first, cefotaxime, vancomycin and levofloxacin in the second, and erythromycin and ciprofloxacin in the third, respectively. Legionella pneumophila pneumonia is clinically not clearly distinct from other pneumonias and has a high mortality rate when not treated with the proper antibiotics. For that reason, adequate and swift diagnosis is of great importance. The urinary antigen test meets both of these criteria. Still, it is advisable to use culture and serology as well if Legionnaires' disease is suspected in a patient, since the urinary antigen test has limitations. In addition, patient isolates are ofepidemiological importance for public health. By comparing available patient isolates with Legionella strains from water sources, it is possible to identify sources of infection. In 2002, based on this principle, a project was started in The Netherlands aimed at identifying sources of infection, thereby preventing outbreaks of Legionnaires' disease by swift elimination of the source. Since the start of the project, 29 sources have been identified. In the cases described above these were a sauna, a cooling tower and a caravan, respectively. In suspected cases, respiratory-tract fluid must be collected to make possible such a source investigation.