Molecular typing of Leptospira spp. in farmed and wild mammals reveals new host-serovar associations in New Zealand

AIMS

To apply molecular typing to DNA isolated from historical samples to determine Leptospira spp. infecting farmed and wild mammals in New Zealand.

MATERIALS AND METHODS

DNA samples used in this study were extracted from urine, serum or kidney samples (or Leptospira spp. cultures isolated from them) collected between 2007 and 2017 from a range of domestic and wildlife mammalian species as part of different research projects at Massey University. Samples were included in the study if they met one of three criteria: samples that tested positive with a lipL32 PCR for pathogenic Leptospira; samples that tested negative by lipL32 PCR but were recorded as positive to PCR for pathogenic Leptospira in the previous studies; or samples that were PCR-negative in all studies but were from animals with positive agglutination titres against serogroup Tarassovi. DNA samples were typed using PCR that targeted either the glmU or gyrB genetic loci. The resulting amplicons were sequenced and typed relative to reference sequences.

RESULTS

We identified several associations between mammalian hosts and Leptospira strains/serovars that had not been previously reported in New Zealand. Leptospira borgpetersenii strain Pacifica was found in farmed red deer (Cervus elaphus) samples, L. borgpetersenii serovars Balcanica and Ballum were found in wild red deer samples, Leptospira interrogans serovar Copenhageni was found in stoats (Mustela erminea) and brushtail possums (Trichosurus vulpecula), and L. borgpetersenii was found in a ferret (Mustela putorius furo). Furthermore, we reconfirmed previously described associations including dairy cattle with L. interrogans serovars Copenhageni and Pomona and L. borgpetersenii serovars Ballum, Hardjo type bovis and strain Pacifica, sheep with L. interrogans serovar Pomona and L. borgpetersenii serovar Hardjo type bovis, brushtail possum with L. borgpetersenii serovar Balcanica, farmed deer with L. borgpetersenii serovar Hardjo type bovis and hedgehogs (Erinaceus europaeus) with L. borgpetersenii serovar Ballum.

CONCLUSIONS

This study provides an updated summary of host-Leptospira associations in New Zealand and highlights the importance of molecular typing. Furthermore, strain Pacifica, which was first identified as Tarassovi using serological methods in dairy cattle in 2016, has circulated in animal communities since at least 2007 but remained undetected as serology is unable to distinguish the different genotypes.

CLINICAL RELEVANCE

To date, leptospirosis in New Zealand has been diagnosed with serological typing, which is deficient in typing all strains in circulation. Molecular methods are necessary to accurately type strains of Leptospira spp. infecting mammals in New Zealand.

Clinical characterisation of pneumonia caused by atypical pathogens combining classic and novel predictors

The aim of this study was to characterise community-acquired pneumonia (CAP) caused by atypical pathogens by combining distinctive clinical and epidemiological features and novel biological markers. A population-based prospective study of consecutive patients with CAP included investigation of biomarkers of bacterial infection, e.g., procalcitonin, C-reactive protein and lipopolysaccharide-binding protein (LBP) levels. Clinical, radiological and laboratory data for patients with CAP caused by atypical pathogens were compared by univariate and multivariate analysis with data for patients with typical pathogens and patients from whom no organisms were identified. Two predictive scoring models were developed with the most discriminatory variables from multivariate analysis. Of 493 patients, 94 had CAP caused by atypical pathogens. According to multivariate analysis, patients with atypical pneumonia were more likely to have normal white blood cell counts, have repetitive air-conditioning exposure, be aged <65 years, have elevated aspartate aminotransferase levels, have been exposed to birds, and have lower serum levels of LBP. Two different scoring systems were developed that predicted atypical pathogens with sensitivities of 35.2% and 48.8%, and specificities of 93% and 91%, respectively. The combination of selected patient characteristics and laboratory data identified up to half of the cases of atypical pneumonia with high specificity, which should help clinicians to optimise initial empirical therapy for CAP.

Examination of the anatomic relationship of the proximal germinal nail matrix to the extensor tendon insertion

The purpose of this study was to delineate the relationship of the terminal extensor tendon insertion to the proximal limit of the germinal nail matrix. Sixteen fresh-frozen human cadaver fingers without any evidence of trauma (average age, 55 years; 3 males and 1 female) were used for this study. Under x25 magnification the proximal limit of the germinal nail matrix and the terminal bony insertion of the extensor tendon were identified. The distance from the terminal tendon insertion to the germinal nail matrix was ascertained using precision calipers. The average distance from the terminal extensor tendon insertion to the proximal edge of the germinal nail matrix was found to be 1.2 mm. We conclude that the proximal limit of the germinal matrix is extremely close to the terminal extensor tendon bony insertion. When the extensor tendon insertion is visualized during operative exposures of the dorsum of the distal phalanx, care should be taken to avoid damaging the germinal matrix. Conversely, when the nail bed is being completely excised, visualization of the insertion of the extensor tendon will indicate that further proximal dissection is not required.

Prevalence of antiviral drug resistance in untreated patients with cytomegalovirus retinitis

The purpose of this study was to determine the prevalence of UL97 resistance mutations in cytomegalovirus (CMV) DNA amplified from the eyes of patients with AIDS and newly diagnosed CMV retinitis. Relevant segments of the CMV UL97 gene were amplified from vitreous humor, after which restriction digest screening was performed for resistance mutations at codons 460, 520, 591, 592, 594, 595, and 603. Mutations were confirmed by DNA sequencing. Vitreous from 21 eyes with AIDS-related non-CMV viral retinitis served as negative controls. CMV DNA was successfully amplified from 195 of 204 eyes. A resistance mutation was found in only a single eye, a T-->G mutation at base 1774, predicting a cysteine to glycine mutation at codon 592. The prevalence of UL97 resistance mutations in the eyes of patients with newly diagnosed CMV retinitis is very low.

Nurse management of patients with minor illnesses in general practice: multicentre, randomised controlled trial

OBJECTIVE

To assess the acceptability and safety of a minor illness service led by practice nurses in general practice.

DESIGN

Multicentre, randomised controlled trial.

SETTING

5 general practices in south east London and Kent representing semi-rural, suburban, and urban settings.

PARTICIPANTS

1815 patients requesting and offered same day appointments by receptionists.

INTERVENTION

Patients were assigned to treatment by either a specially trained nurse or a general practitioner. Patients seen by a nurse were referred to a general practitioner when appropriate.

MAIN OUTCOME MEASURES

The general satisfaction of the patients as measured by the consultation satisfaction questionnaire. Other outcome measures included the length of the consultation, number of prescriptions written, rates of referral to general practitioners, patient's reported health status, patient's anticipated behaviour in seeking health care in future, and number of patients who returned to the surgery, visits to accident and emergency, and out of hours calls to doctors.

RESULTS

Patients were very satisfied with both nurses and doctors, but they were significantly more satisfied with their consultations with nurses (mean (SD) score of satisfaction 78.6 (16. 0) of 100 points for nurses v 76.4 (17.8) for doctors; 95% confidence interval for difference between means -4.07 to -0.38). Consultations with nurses took about 10 minutes compared with about 8 minutes for consultations with doctors. Nurses and doctors wrote prescriptions for a similar proportion of patients (nurses 481/736 (65.4%) v doctors 518/816 (63.5%)). 577/790 (73%) patients seen by nurses were managed without any input from doctors.

CONCLUSION

Practice nurses seem to offer an effective service for patients with minor illnesses who request same day appointments.

[Tracheobronchial involvement in non-Hodgkin's lymphoma]

Tracheobronchial involvement in non-Hodgkin's lymphoma (NHL) has been little described. We present two patients with NHL and endobronchial involvement of different characteristics. In the first case diffuse involvement of the bronchial mucosa was observed in the context of a systemic NHL of 10 years' duration. In the second patient, endobronchial involvement consisted of a mass obstructing the trachea and the right main bronchus which was the first manifestation of lymphoma.