Haemoglobin and red cell counts in leptospirosis patients infected with different serovars.

Introduction: The aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars.

Methods: The study retrospectively compared the haemoglobin and red cell count results from the first blood samples taken from 207 patients at presentation to a Queensland Health hospital.

Results: Significant differences were observed in haemoglobin and red cell counts in those infected with Leptospira interrogans serovars Szwajizak and Canicola when compared with most of the other serovars.

Molecular epidemiology of Leptospira borgpetersenii serovar Arborea, Queensland, Australia, 1998-2005.

Leptospira borgpetersenii serovar Arborea is an emerging cause of leptospirosis in Australia. It was not previously recognized as an endemic serovar before the 1990s, but at that point, human infections with the serovar increased significantly. Using fluorescent-amplified fragment-length polymorphism (FAFLP) molecular typing, human and rodent isolates were compared genetically.

The microscopic agglutination test (MAT) is an unreliable predictor of infecting Leptospira serovar in Thailand.

A prospective study in Thailand identified 106 patients with culture-proven leptospirosis. The accuracy of the microscopic agglutination test (MAT) in predicting the infecting serovar was evaluated in 78/106 (74%) patients with a diagnostic titer. MAT correctly determined the infecting serovar in 26 cases (33%), indicating that this assay is a poor predictor of infecting serovar in our setting.

Reclassification of Leptospira meyeri serovar Perameles to Leptospira interrogans serovar Perameles through serological and molecular analysis: evidence of a need for changes to current procedures in Leptospira taxonomy.

It has been recognized that there is heterogeneity among Leptospira isolates in culture collections worldwide, causing confounding results for researchers utilizing these organisms; one such culture is Leptospira meyeri serovar Perameles. The serovar reference strain Bandicoot 343 was previously identified to the species level by DNA-DNA hybridization; however, subsequent published studies demonstrated results that contradicted the initial speciation. In this study, initial serological testing was performed with isolates from the culture collections of the Centers for Disease Control (CDC), Atlanta, USA (strain Lepto0214), and the WHO/FAO/OIE Collaborating Centre for Reference and Research on Leptospirosis, Brisbane, Australia (strain Bandicoot 343), and the original serovar Perameles hyperimmune antiserum produced in 1964.

Lymphopenia is observed regularly in the acute (leptospiraemic) phase but not the immune phase of leptospirosis.

Lymphocyte counts in patients with leptospirosis have been shown to be variable. This study retrospectively compared lymphocyte counts from the first blood samples taken following hospital presentation in patients with leptospirosis who were either (i) IgM non-reactive, (ii) IgM reactive and microscopic agglutination test (MAT) non-reactive or (iii) IgM and MAT reactive in an effort to determine whether differences in lymphocyte counts are observed in the acute and immune phase of leptospirosis. Statistical differences in lymphocyte counts were observed between the three groups.

Leptospira kmetyi sp. nov., isolated from an environmental source in Malaysia.

A single Leptospira strain (designated Bejo-Iso9(T)) was isolated from a soil sample taken in Johor, Malaysia. The isolate showed motility and morphology typical of the genus Leptospira under dark-field microscopy. Cells were found to be 10-13 microm in length and 0.

Leptospira wolffii sp. nov., isolated from a human with suspected leptospirosis in Thailand.

A single Leptospira strain (designated Khorat-H2(T)) was isolated from the urine of an adult male patient with suspected leptospirosis from the province of Nakornrachasima, Thailand. The isolate showed typical Leptospira motility and morphology under dark-field microscopy. Cells were 10-13 mum long and 0.

Epidemiology of Leptospira weilii serovar Topaz infections in Australia.

Leptospirosis is a zoonotic disease with a worldwide distribution. Leptospira weilii serovar (sv.) Topaz is a newly described serovar first isolated in the far north of Queensland, Australia.

Leptospirosis serology in the common brushtail possum (Trichosurus vulpecula) from urban Sydney, Australia.

The common brushtail possum (Trichosurus vulpecula) is indeed a common marsupial in major cities of Australia. This species is known to be susceptible to leptospirosis and often lives in close contact with humans, raising concerns about the potential for transmission of this disease in urban areas. A total of 192 brushtail possum blood samples were collected from 136 individuals in suburban areas of metropolitan Sydney from November 2002 to November 2004.

Clinical diagnosis and geographic distribution of leptospirosis, Thailand.

We defined the positive predictive accuracy of a hospital-based clinical diagnosis of leptospirosis in 9 provinces across Thailand. Of 700 suspected cases, 143 (20%) were confirmed by laboratory testing. Accuracy of clinical diagnosis varied from 0% to 50% between the provinces and was highest during the rainy season.

Optimization of culture of Leptospira from humans with leptospirosis.

A prospective study of 989 patients with acute febrile illness was performed in northeast Thailand to define the yield of Leptospira from four different types of blood sample. Based on a comparison of the yields from whole blood, surface plasma, deposit from spun plasma, and clotted blood samples from 80 patients with culture-proven leptospirosis, we suggest a sampling strategy in which culture is performed using whole blood and deposit from spun plasma.

Identification of pathogenic Leptospira species by conventional or real-time PCR and sequencing of the DNA gyrase subunit B encoding gene.

Background: Leptospira is the causative genus of the disease, leptospirosis. Species identification of pathogenic Leptospira in the past was generally performed by either DNA-DNA hybridisation or 16s rRNA gene sequencing. Both methods have inherent disadvantages such as the need for radio-labelled isotopes or significant homology between species.

Development of a Multiple-Locus Variable Number of Tandem Repeat Analysis (MLVA) for Leptospira interrogans and its application to Leptospira interrogans serovar Australis isolates from Far North Queensland, Australia.

Background: Leptospirosis is a zoonotic disease caused by the genus, Leptospira. Leptospira interrogans is the most common genomospecies implicated in the disease. Epidemiological investigations are needed to distinguish outbreak situations or to trace reservoirs of the organisms.

A quantitative PCR (TaqMan) assay for pathogenic Leptospira spp.

Background: Leptospirosis is an emerging infectious disease. The differential diagnosis of leptospirosis is difficult due to the varied and often "flu like" symptoms which may result in a missed or delayed diagnosis. There are over 230 known serovars in the genus Leptospira.