Identification of compounds for improved growth of Leptospira in culture and isolation

Metagenomic next-generation sequencing in the early diagnosis of leptospirosis infection presenting as acalculous cholecystitis and septic shock in a non-epidemic area after typhoons: A case report

Key Clinical Message

Leptospirosis is an important zoonosis worldwide. Due to nonspecific clinical manifestation and poor recognition in non-epidemic area, there is often a delay in diagnosis and treatment. Early diagnosis from Metagenomic next-generation sequencing test is crucial for timely intervention.

Abstract

We presented a case of a 19-year-old male patient who developed leptospirosis infection characterized by acalculous cholecystitis and septic shock after typhoon events. Metagenomic next-generation sequencing (mNGS) helped to early diagnose leptospirosis infection. Finally, the patient achieved full recovery following the antibiotic treatment in addition to supportive care and was discharged.

Metagenomic next-generation sequencing for diagnosing severe leptospirosis in a patient suspected COVID-19: A case report

Leptospirosis is a zoonotic and neglected waterborne disease caused by the pathogenic helical spirochetes. Early diagnosis of leptospirosis remains challenging due to non-specific symptoms and the limited availability of rapid point-of-care diagnostic tests. Herein, we present a case where a patient suspected of having COVID-19 was diagnosed with leptospirosis using metagenomic next-generation sequencing (mNGS). This case highlights the potential of mNGS to diagnose leptospirosis in the context of the COVID-19 pandemic.

Enhancing leptospirosis control with nanosensing technology: A critical analysis

Leptospirosis is a serious health problem in tropical areas; thus, animals shed leptospires in the environment. Humans are accidental hosts infected through exposure to contaminating bacteria in the environment. One health strategy can be applied to protect and eliminate leptospirosis because this cooperates and coordinates activities between doctors, veterinarians, and ecologists. However, conventional methods still have limitations. Therefore, the main challenges of leptospirosis control are the high sensing of detection methods to screen and control the pathogens. Interestingly, nano sensing combined with a leptospirosis detection approach can increase the sensitivity and eliminate some limitations. This article reviews nanomaterial development for an advanced leptospirosis detection method, e.g., latex beads-based agglutination test, magnetic nanoparticles enrichment, and gold-nanoparticles-based immunochromatographic assay. Thus, nanomaterials can be functionalized with biomolecules or sensing molecules utilized in various mechanisms such as biosensors. Over the last decade, many biosensors have been developed for Leptospira spp. pathogen and others. The evolution of biosensors for leptospirosis detection was designed for high efficiency and might be an alternative tool. In addition, the high-sensing fabrications are useful for leptospires screening in very low levels, for example, soil or water from the environment.

A rare case of severe leptospirosis infection presenting as septic shock in a non-endemic area: a case report and literature review

BACKGROUND

Leptospirosis is a zoonosis caused by spirochete "genus" leptospira. The clinical presentations of leptospirosis range from an influenza-like presentation of fever and myalgia, to severe forms. Leptospirosis can potentially lead to a misdiagnosis or delay in diagnosis when clinical similarities exist.

CASE PRESENTATION

A 63-year-old man presented with fever, shock and thrombocytopenia followed by diffuse pulmonary hemorrhage. Peripheral blood Metagenomic Next-generation Sequencing (mNGS) reported Leptospira interrogans. The patient was treated with piperacillin-tazobactam (TZP) plus doxycycline and improved dramatically after 7 days.

CONCLUSION

We conclude that leptospirosis can potentially lead to a misdiagnosis or delay in diagnosis. Correctly evaluation of thrombocytopenia in acute febrile illnesses facilitates the differential diagnosis of leptospirosis. mNGS can accurately detect Leptospira DNA during the early stage of the infection.

Co-Infection by Leptospira montravelensis and Leptospira interrogans Serovar Pomona in Urine Samples of Donkeys and Pigs in Sardinia, Italy

Saprophytic leptospires are spirochetes enclosed within the non-pathogenic clade of the genus Leptospira, which in turn is subdivided into two subclades S1 and S2. To date, the microorganisms included in these subclades have been isolated from the environment in various parts of the world, and are believed to have no known animal reservoirs. After a case of Leptospira interrogans serovar Pomona was notified to the owner of a farm in Sardinia, all of the farm animals (11 pigs and 3 donkeys) were examined for the presence of Leptospira. Sera of all tested animals resulted positive for antibodies to Leptospira using a microscopic agglutination test (MAT). Moreover, nine (82%) kidney samples from pigs and three urine samples collected from donkeys (100%) tested positive for Leptospira DNA after qPCR. Results obtained after MLST analysis and sequencing of rrs, rpoB, and secY genes, performed on six Leptospira strains isolated in culture, revealed the presence of the genomospecies L. interrogans serovar Pomona in the kidney samples. Conversely, whole-genome sequencing combined with mean nucleotide identity revealed the presence of the saprophytic L. montravelensis in the urine samples. Our results report, for the first time, the isolation of a saprophytic species from mammalian urine, suggesting a new ecological specialization for these bacteria, with a possible transition from free-living to a symbiotic lifestyle. Further studies will have to be conducted to understand the evolution of virulence of these bacteria, potential infectivity, and possible public health implications.

Improvement of the enrichment used in the EMJH medium (Ellinghausen-McCullough-Johnson-Harris) for the cultivation of Leptospira spp

Changes were made to the original formulation of the EMJH medium (Ellinghausen-McCullough-Johnson-Harris) enrichment and some aspects such as growth time of Leptospira and utilization in the microscopic agglutination test (MAT) were evaluated and compared to the original enrichment and to a commercially available enrichment (DIFCO™). Leptospira samples (24 antigens) that make up our panel of antigens used in MAT were used, among them, reference and autochthonous strains isolated in Brazil. The samples were grown individually in the EMJH medium under the three previously mentioned conditions (adapted enrichment, original enrichment and commercial enrichment). In addition, 89 blood serums from domestic and wild animals were analyzed by MAT using the antigens grown in these media. All samples tested grew efficiently with the adapted enrichment, and the MAT results were satisfactory. Therefore, other laboratories could also benefit from the use of this adapted enrichment when culturing the Leptospira strains applied in their MAT panels.

Leptospirosis with pulmonary haemorrhage and multiple organ failure: a case report and literature review

Pulmonary haemorrhage is an important complication of leptospirosis. We herein report an uncommon case of severe pulmonary haemorrhage and multiple organ failure caused by leptospirosis in a 49-year-old man who was previously healthy. He was a farm worker who was admitted to the hospital because of haemoptysis. He had worked in a paddy field 4 days prior to admission. Chest computed tomography revealed pulmonary haemorrhage, which rapidly deteriorated into haemorrhagic shock and multiple organ failure. Based on the patient’s possible history of contact with contaminated water and the DNA sequence of Leptospira detected in his bronchoalveolar lavage fluid, the patient was diagnosed with pulmonary haemorrhagic leptospirosis. Despite the administration of a fluid bolus, norepinephrine, broad-spectrum antibiotics, and haemostatics, and even with administration of a blood transfusion and extracorporeal life support, the pulmonary haemorrhage could not be controlled effectively. The patient eventually died of haemorrhagic shock. Leptospirosis can be a life-threatening disease despite aggressive treatment, even with extracorporeal life support. Next-generation sequencing can provide important diagnostic clues for patients with atypical leptospirotic symptoms.

Leptospira transport medium (LTM): A practical tool for leptospires isolation

The isolation of Leptospira is challenging, since the bacteria of this genus are susceptible to adverse environmental conditions and may not remain viable for extend periods in urine samples. This study attempted to develop and evaluate a simple and practical method to isolate leptospires from bovine urine samples. A culture medium for sample transport, named Leptospira Transport Medium (LTM), was described and validated using reference serovars of Leptospira spp. in addition to autochthonous strains isolated in Brazil. We evaluated LTM in the field, by collecting 215 urine samples from slaughtered cattle and immediately seeding them in LTM and Fletcher's medium, used as control. The cultures were sent to a laboratory within 10 days for further processing. Moreover, 16S PCR was also performed on the urine samples directly to detect Leptospira DNA. Using LTM enabled 52 isolates (24.2%) to be obtained in pure culture, and contamination was only observed in 15/215 samples (7.0%). Regarding the samples in Fletcher's medium, 10 (4.6%) isolates were obtained. With 16S PCR performed in the urine samples, 31 samples (14.4%) were determined to be positive. LTM was developed and used in a simple and practical way and can significantly improve the isolation of leptospires from urine samples, as well as being highly useful in remote areas, not only in Brazil but also in other countries where few easily accessible laboratories are available. Furthermore, LTM can be prepared by laboratories and provided to veterinarians and technicians for urine collection in the field.