Cases Of Severe Leptospirosis Research Articles

Severe course of leptospirosis: A case report

This study describes a clinical case of severe leptospirosis. Patient K., was admitted to the neurosurgical department on November 26, 2023, with a diagnosis of “Closed craniocerebral injury dated 22.11.2023. Severe brain injury. Linear fracture of the occipital bone. Eyelid hematoma. An abrasion of the upper eyelid on the right.” On November 29, 2023, an objective examination drew attention to an increase in body temperature to 39.5°C, subictericity of the sclera and skin, and conjunctival injections. Hemorrhagic rash appeared on the skin of the trunk and limbs. The hemodynamics was unstable, with episodes of arterial hypotension. Laboratory examination revealed mild anemia, signs of hepatic–renal insufficiency, hyperbilirubinemia, and increased concentrations of creatine phosphokinase, C-reactive protein, and procalcitonin. Fluctuations in hepatic–renal insufficiency and levels of creatine phosphokinase and procalcitonin increased. In addition, the differential diagnostic search aimed at identifying the following infectious diseases: hemorrhagic fever with renal syndrome, leptospirosis, malaria, and viral hepatitis. IgM to Leptospira interrogans were detected (December 11, 2023). The patient received antibacterial therapy, extracorporeal detoxification, artificial ventilation, infusion therapy, and correction of the hemostasis system. With the complex treatment, the patient’s condition stabilized, and the patient was discharged from the hospital on the 61st day with restoration of health.

Overview of Leptospirosis

Leptospirosis is one of the most important zoonoses worldwide and is a major public health problem in many countries. The disease is caused by spirochetes of the genus Leptospira and is transmitted through contact of abraded skin or mucous membranes with contaminated rodent urine, water, or soil. It is estimated that there are more than one million cases of severe leptospirosis per year worldwide. Leptospirosis can cause severe multiple organ failure with a mortality rate as high as 50%. Early recognition, diagnosis and treatment of leptospirosis can reduce morbidity and mortality. This overview will look out Leptospirosis thoroughly from the epidemiological burden, pathogenesis, clinical presentation and diagnosis, the current treatment and preventive leptospirosis

Characterization of cellular immune response in hamsters immunized with recombinant vaccines against leptospirosis based on LipL32:LemA:LigAni chimeric protein

In the last 20 years, various research groups have endeavored to develop recombinant vaccines against leptospirosis to overcome the limitations of commercially available bacterins. Numerous antigens and vaccine formulations have been tested thus far. However, the analysis of cellular response in these vaccine formulations is not commonly conducted, primarily due to the scarcity of supplies and kits for the hamster animal model. Our research group has already tested the Q1 antigen, a chimeric protein combining the immunogenic regions of LipL32, LemA, and LigANI, in recombinant subunit and BCG-vectored vaccines. In both strategies, 100 % of the hamsters were protected against clinical signs of leptospirosis. However, only the recombinant BCG-vectored vaccine provided protection against renal colonization. Thus, the objective of this study is to characterize the cellular immune response in hamsters immunized with different vaccine formulations based on the Q1 antigen through transcriptional analysis of cytokines. The hamsters were allocated into groups and vaccinated as follows: recombinant subunit (rQ1), recombinant BCG (rBCG:Q1), and saline and BCG Pasteur control vaccines. To assess the cellular response induced by the vaccines, we cultured and stimulated splenocytes, followed by RNA extraction from the cells and analysis of cytokines using real-time PCR. The results revealed that the recombinant subunit vaccine elicited a Th2-type response, characterized by the expression of cytokines IL-10, IL-1α, and TNF-α. This pattern closely resembles the cytokines expressed in severe cases of leptospirosis. On the other hand, the rBCG-vectored vaccine induced a Th1-type response with significant up-regulation of IFN-γ. These findings suggest the involvement of the cellular response and the IFN-γ mediated inflammatory response in the sterilizing immunity mediated by rBCG. Therefore, this study may assist future investigations in characterizing the cellular response in hamsters, aiming to elucidate the mechanisms of efficacy and establish potential correlates of protection.

Severe Leptospirosis (Weil’s Disease) with Multiple Organ Failure in Urban Setting: A Case Report

Leptospirosis is a rare disease that could cause multiple organ failures and death if left untreated. The correct treatment will determine the recovery of patients. A 28-years old male came to the Emergency Department with profuse diarrhea. No prior medical history; worked as a private employee recently assigned to collect rat traps one week before. Laboratories show severe thrombocytopenia, acute liver failure, and acute renal failure support by imaging with the conclusion of hepatomegaly with normal kidney size. During observation in the emergency room, the patient worsens into septic shock. The patient was treated in intensive care, diagnosed with Weil's disease, and treated given antibiotics with aggressive fluid therapy; dialysis was postponed, and close monitoring of the patient's symptoms and organ function. After five days of care, clinical symptoms and organ function improved, and the patient was discharged well. Diagnosis of Leptospirosis is challenging with a combination of signs and symptoms that are not commonly found. Therefore, primary treatment is antibiotic and supportive care such as renal replacement therapy is not routinely needed as long there are improvements in close monitoring. This objective is to increase awareness and treatment option for further severe leptospirosis cases

ОСОБЕННОСТИ ЭПИДЕМИОЛОГИИ ЛЕПТОСПИРОЗА

The authors present the clinical and epidemiological features of leptospirosis among residents in Belarus. The main reservoirs of infection are described. We have demonstrated a clinical case of severe leptospirosis. To solve the set tasks in this research, we used methods of epidemiological diagnostics and statistical research methods. According to the results obtained, the incidence of leptospirosis in Belarus for the studied interval (2007—2020) was unevenly distributed over the years. The maximum and minimum indicators differed six times. The average long-term incidence rate was 0.25 cases per 100 000 population (95 % CI 0.2—0.3). The analyzed period was characterized by a stable long-term epidemic trend towards a decrease in morbidity. Severe clinical signs of leptospirosis have been associated with L. incterohaemorragiae in a male patient. The highest average annual incidence rates of leptospirosis were noted in the Mogilev and Gomel regions (0.85 %00 and 0.49 %00), and the lowest rates were recorded in the Brest region (0.03 %00).

C87. Serial Cases of Cardiovascular Manifestation on Leptospirosis: A Tales of Unfortunate Events

Abstract Background Leptospirosis is a zoonosis disease caused by Leptospira species. It's endemic and has become a major public health issue, especially in tropical regions. Clinical manifestation varies from mild or asymptomatic to severe multiple organ failure. We report cases of severe leptospirosis which complicates supraventricular tachycardia and myoperdicarditis from Universitas Sebelas Maret Academic Hospital. Case Summary The first case was a 44-year-old man referred from Internal Medicine Department with Leptospira infection with Weil’s disease. On 5th daycare, the patient was reporting had an episode of tachyarrhythmia, the ECG show SVT-AVNRT, there was no history of arrhythmic events before admitted to the hospital, the echocardiography was normal. The second case was a 67-year-old man who was referred from emergency department with shortness of breath, the ECG reveals diffuse ST-segment elevation in all limb and precordial leads with reciprocal ST-depression at aVR and V1, there was also downsloping of the PR and TP segment on precordial leads (Spodick’s sign), with normal ejection fraction on echocardiographic examination with pericardial thickening. Both patients have hsTroponin levels rose above the normal limit and serological testing found positive leptospira IgM. Discussion Severe leptospirosis can cause multi-organ dysfunction including cardiac involvement. The patients, in this case, suffered from leptospirosis with SVT-AVNRT and myopericarditis. The exact pathophysiology is still unclear, but there are several hypotheses, such as cytokine storms and direct damage from leptospira endotoxins. Arrhythmias and cardiac disturbance in leptospirosis patients are associated with poor outcomes and higher mortality rates.

C87. Serial Cases of Cardiovascular Manifestation on Leptospirosis: A Tales of Unfortunate Events

Abstract Background Leptospirosis is a zoonosis disease caused by Leptospira species. It's endemic and has become a major public health issue, especially in tropical regions. Clinical manifestation varies from mild or asymptomatic to severe multiple organ failure. We report cases of severe leptospirosis which complicates supraventricular tachycardia and myoperdicarditis from Universitas Sebelas Maret Academic Hospital. Case Summary The first case was a 44-year-old man referred from Internal Medicine Department with Leptospira infection with Weil’s disease. On 5th daycare, the patient was reporting had an episode of tachyarrhythmia, the ECG show SVT-AVNRT, there was no history of arrhythmic events before admitted to the hospital, the echocardiography was normal. The second case was a 67-year-old man who was referred from emergency department with shortness of breath, the ECG reveals diffuse ST-segment elevation in all limb and precordial leads with reciprocal ST-depression at aVR and V1, there was also downsloping of the PR and TP segment on precordial leads (Spodick’s sign), with normal ejection fraction on echocardiographic examination with pericardial thickening. Both patients have hsTroponin levels rose above the normal limit and serological testing found positive leptospira IgM. Discussion Severe leptospirosis can cause multi-organ dysfunction including cardiac involvement. The patients, in this case, suffered from leptospirosis with SVT-AVNRT and myopericarditis. The exact pathophysiology is still unclear, but there are several hypotheses, such as cytokine storms and direct damage from leptospira endotoxins. Arrhythmias and cardiac disturbance in leptospirosis patients are associated with poor outcomes and higher mortality rates.

New Insights on Leptospira Infections in a Canine Population from North Sardinia, Italy: A Sero-Epidemiological Study.

Simple SummaryLeptospirosis is a widespread zoonosis caused by pathogenic spirochaetes of the genus Leptospira. Pathogenic leptospires live in the kidneys of different mammalian species and are excreted in the environment with the urine. The infection of humans is mainly caused by direct contact with infected animals or indirectly by contact with a contaminated environment. The aim of this study was to perform a sero-epidemiological survey to assess the presence of antibodies against Leptospira serovars in a representative sample of kennel and owned dogs from a selected area of Sardinia Island. In addition, kidney homogenates from rodents collected from the same study area were also analyzed by culture-based and real-time PCR-based testing methods. Higher antibody titers were observed against Leptospira Icterohaemmorrhagiae, which is believed to be responsible for the majority of severe cases of leptospirosis in humans. The detection of pathogenic Leptospira serotypes in dogs from northern Sardinia may represent a potential risk of infection for humans and contribute to the spread of the bacteria in the environment. Public health strategies to control possible Leptospira outbreaks should be implemented to prevent the disease from becoming a major medical and veterinary problem in this region.Leptospirosis is a widespread zoonosis recognized as a re-emerging infectious disease in a wide variety of animal species, including humans and dogs. No data exist regarding the presence of Leptospira species in the canine population of Sardinia Island. This study reports the first sero-survey for leptospirosis in kennel and owned dogs from six areas of the north of Sardinia. Sera from 1296 dogs were tested by microscopic agglutination test (MAT) specific for nine different serovars that are known to be well widespread in the Mediterranean environment. Moreover, kidney homogenates from rodents collected from the study area were also analyzed by LipL32 real-time PCR and multi-locus sequence type (MLST) on the basis of the analysis of seven concatenated loci. A total of 13% of the examined sera (95%CI: 11–15) tested positive for one or more serovars of Leptospira MAT detected; antibodies for serogroup Icterohaemorrhagiae (57%; 95%CI: 49–65) were the most common, followed by serovars Bratislava (22%; 95%CI: 16–28), Canicola (14%; 95%CI: 9–19), and Grippotyphosa (7%; 95%CI: 3–11). MLST analyses on isolates from rodents identified L. interrogans and L. borgpetersenii genomospecies. Different serovars belonging to pathogenic Leptospira serogroups are circulating in dogs from the island. Moreover, data obtained from rodents, indicated that rodents likely act as reservoir of spirochetes. Further sero-epidemiological studies are needed in order to obtain data from other collection sites in Sardinia and to increase the information on Leptospira species circulating in this area.

Leptospirosis: Malaysia Leptospirosis Research network experience

Background: Leptospirosis is a rat-borne bacterial infection caused by pathogenic Leptospira species has a global distribution affecting humans and a wide range of mammalian species. The disease is endemic in most tropical and subtropical regions, with risk influenced by flood, adventure travel, lack of sanitation and explosive population of rodent reservoirs. The first human case of severe leptospirosis was recognized in 1927 in Malaysia. Today at least 33,000 cases with 450 deaths have been recorded since its gazettement as a notifiable disease in 2010. Malaysia Leptospirosis research network (MyLepto) was formed in 2015 to understand the issues or challenges related to leptospirosis in Malaysia. One of the main objective of the MyLepto was to identify the rodent carrying and human infecting species and also to assess the gold standard techniques such as PCR and MAT in early diagnosis of the illness. Methods & Materials: For identifying the human infecting species, we performed lipL32 PCR and partial 16S rDNA (rrs) in patients clinically suspected for leptospirosis, while for rodents carrying strains, kidneys for small mammals trapped in hot spot and outbreak areas were cultured and confirmed by PCR. Results: For human, from a total of 165 patients, 92 (56%) were confirmed positive for leptospirosis through MAT (n = 43; 47%), PCR (n = 63; 69%) or both MAT and PCR (n = 14; 15%). The infecting Leptospira species determined by partial 16S rDNA (rrs) gene sequencing revealed two pathogenic Leptospira species namely L. interrogans (n = 44, 70%) and L. kirschneri (n = 17, 27%) and one intermediate species L. wolffii (n = 2, 3%). While for small mammals, an overall prevalence of 14.2% was detected comprising four species which include L. interrogans, L. kirschneri, L. borgpetersenii and L. weilii. Conclusion: The detection of similar species from rodents and human emphasizes the need for public health awareness on exposure to rodents.

The Predictive Factors for Severe Leptospirosis Cases in Kedah.

Over the past decade, increased awareness about leptospirosis disease in developing and industrialized countries has resulted in increased numbers of leptospirosis cases being reported worldwide. About 5% to 15% of leptospirosis patients end up with severe forms of the disease. Complication due to leptospirosis requires monitoring, specific treatments, and intensive care admission, thus increasing the cost of treating severe leptospirosis cases. Currently, we have data on incident and mortality rates, but we do not have data on the number of patients with severe form of leptospirosis or how many patients have complications, and whether or not these complications were resolved. Therefore, we carried out this study to determine the predictive factors for severe leptospirosis cases in Kedah. We conducted a cross-sectional study. The data of patients diagnosed with leptospirosis were obtained from the surveillance unit, Kedah Health Department, through the e-notification system. These data were then sorted according to the hospitals where the patients were admitted. The patients’ medical records were collected, and their information was obtained using a checklist. A total of 456 confirmed leptospirosis cases were included in the study, with 199 patients classified as severe cases and 257 patients as mild cases, based on the Malaysian leptospirosis guidelines. Most patients were male (71.5%) with a mean SD age of 36.62 ± 20.75 years. The predictive factors for severe leptospirosis include abnormal lung sounds (OR: 3.07 [CI 1.58–6.00]), hepatomegaly (OR: 7.14 [1.10–45.98]), hypotension (OR: 2.16 [1.08–4.34]), leukocytosis (OR: 2.12 [1.37–3.29]), low hematocrit (OR: 2.33 [1.43–3.81]), and increased alanine aminotransferase (SGPT ALT) (OR: 2.12 [1.36–3.30]). In conclusion, knowing these predictive factors will help clinicians identify severe leptospirosis cases earlier and develop their treatment plans accordingly, to reduce the complications and death from severe leptospirosis.

Polyneuritis and Rare Sequelae of Leptospirosis Contracted While on an Urban Clean-Up Mission in Detroit : A Case Report of Weil’s Disease and Literature Review

Leptospirosis is a common zoonosis, an infectious disease that infects both humans and animals, which is caused by spirochete bacteria from genus Leptospira . Approximately 30% of children in urban Detroit and 16% of adults in Baltimore demonstrated serologic evidence of previous leptospirosis infections. The Detroit study showed correlation between degree of rat infestation and seropositivity rates. This finding suggests rats are major vectors for human leptospirosis in mainland United States. The leptospires from infected animals survive best in fresh water, damp alkaline soil, vegetation, and mud with temperatures higher than 22 °C. Although leptospirosis is a well documented clinical condition, the sequelae of polyneuritis has not yet been reported to our knowledge. The following case is an example of such an occurrence. A 49-year-old Caucasian female presented to the emergency department with flu-like symptoms after volunteering in an urban Detroit neighborhood clean-up project. She admitted to picking up wood from stagnant water without wearing personal protective equipment. The primary differential diagnosis being Weil’s disease from leptospirosis and was proven positive with serologic testing via the Center for Disease Control. A computed tomography (CT) abdomen and pelvis demonstrated lymphadenopathy throughout the abdomen and near the spinal column. She was treated with ceftriaxone and doxycycline for 12 days but developed chronic neuralgia and polyneuritis. Leptospires are known to cause vasculitis. This patient developed polyneuritis either from direct invasion of the nerves from leptospires or compromised blood supply to the nerves. In addition to antibiotics, patients with severe cases of leptospirosis also require supportive therapy and careful management of renal, hepatic, hematologic, and central nervous system complications. If renal failure ensues, early initiation of hemodialysis or peritoneal dialysis may reduce mortality. Rapid identification of symptoms and a high clinical suspicion are paramount because early intervention can save their life. J Med Cases. 2019;10(6):183-187 doi: https://doi.org/10.14740/jmc3320

Clinical characterization of patients with severe leptospirosis in a tertiary hospital in Cali, Colombia, 2010-2016

Introduction: Leptospirosis is an endemic bacterial infection in Colombia. Its clinical course can be variable and occasionally fatal. There are few studies in the country about severe cases of leptospirosis. Objectives: To describe the demographic and clinical characteristics of patients with a diagnosis of leptospirosis, and their management in a high complexity hospital. Materials and methods: This was a descriptive retrospective study of patients with a serologic diagnosis of leptospirosis between 2010 and 2016. Results: We analyzed 87 patients, 74% of them were men, and 84% were older than 18 years; 35% had a comorbidity, the most common being arterial hypertension (16%) and diabetes mellitus (9%). The most frequent symptoms were fever, nausea, fatigue, myalgia, arthralgia, and abdominal pain. The majority of patients required hospitalization in general wards (61%), with a median stay of six days; 34% required management in the intensive care unit, with a median stay of five days. Mortality was 1.1% (n=1). All patients received treatment with either ceftriaxone or doxycycline. Conclusions: There is a risk of leptospira infections having a late diagnosis given their unspecific clinical presentation, which generates a high number of differential diagnoses. The early management in the intensive care unit could decrease the incidence of complications and the mortality of patients with leptospirosis.

Polyneuritis and Rare Sequelae of Leptospirosis Contracted While on an Urban Clean-Up Mission in Detroit : A Case Report of Weil’s Disease and Literature Review

Leptospirosis is a common zoonosis, an infectious disease that infects both humans and animals, which is caused by spirochete bacteria from genus Leptospira . Approximately 30% of children in urban Detroit and 16% of adults in Baltimore demonstrated serologic evidence of previous leptospirosis infections. The Detroit study showed correlation between degree of rat infestation and seropositivity rates. This finding suggests rats are major vectors for human leptospirosis in mainland United States. The leptospires from infected animals survive best in fresh water, damp alkaline soil, vegetation, and mud with temperatures higher than 22 °C. Although leptospirosis is a well documented clinical condition, the sequelae of polyneuritis has not yet been reported to our knowledge. The following case is an example of such an occurrence. A 49-year-old Caucasian female presented to the emergency department with flu-like symptoms after volunteering in an urban Detroit neighborhood clean-up project. She admitted to picking up wood from stagnant water without wearing personal protective equipment. The primary differential diagnosis being Weil’s disease from leptospirosis and was proven positive with serologic testing via the Center for Disease Control. A computed tomography (CT) abdomen and pelvis demonstrated lymphadenopathy throughout the abdomen and near the spinal column. She was treated with ceftriaxone and doxycycline for 12 days but developed chronic neuralgia and polyneuritis. Leptospires are known to cause vasculitis. This patient developed polyneuritis either from direct invasion of the nerves from leptospires or compromised blood supply to the nerves. In addition to antibiotics, patients with severe cases of leptospirosis also require supportive therapy and careful management of renal, hepatic, hematologic, and central nervous system complications. If renal failure ensues, early initiation of hemodialysis or peritoneal dialysis may reduce mortality. Rapid identification of symptoms and a high clinical suspicion are paramount because early intervention can save their life. J Med Cases. 2019;10(6):183-187 doi: https://doi.org/10.14740/jmc3320

Urban-Acquired Leptospirosis in Washington, DC

Abstract Leptospirosis is rarely reported in the United States. Although primarily considered a disease of the tropics or of resource limited areas, leptospirosis is being reported more frequently in industrialized urban areas. We report a case of severe leptospirosis in a man living in Washington, DC, with occupational exposure to rats. A review of the literature was conducted, with a focus on the urban form of the disease, using the MEDLINE database from inception to May 2018.

Severe leptospirosis and pancreatitis; A case series from a leptospirosis outbreak in Anuradhapura district, Sri Lanka.

BackgroundAcute pancreatitis is identified as an atypical and rare presentation of leptospirosis. In this report, we discuss a case series of severe leptospirosis with pancreatitis as a main complication during an unusual outbreak of leptospirosis in Anuradhapura district, Sri Lanka.Case presentationWe retrospectively reviewed clinical presentation, investigations, treatment and outcome of six confirmed cases of severe leptospirosis admitted to intensive care unit (ICU) of Teaching Hospital, Anuradhapura, within a three months period from November 2014 to January 2015.All six patients were previously healthy paddy farmers presented with fever, myalgia and arthralgia. Four patients had abdominal pain, nausea and vomiting on admission. Hypotension, Neutrophilic leukocytosis and thrombocytopaenia was detected in all patients in the initial stage. Four patients had serum amylase more than 900 (range 941–2420). All patients had acute kidney injury and hepatitis. Significantly elevated amylase and low serum calcium were present in 4 cases. Five patients recovered without any evidence of residual organ damage, but one succumbed to the illness.ConclusionThis case series emphasizes the importance of identification of acute pancreatitis as a common complication of Leptospirosis, in order to reduce mortality and morbidity.

AB022. A case of severe leptospirosis with acute respiratory distress syndrome

: Leptospirosis is a microbial infection which occurs in humans and animals and is caused by Leptospira (Leptospira spp.). In Greece, it occurs at a frequency of 0.22:100,000, and 24 severe cases have been reported in 2013. It manifests in three forms: anicteric (90%), icteric (5–10%) and severe. Severe leptospirosis can be a rare cause of acute respiratory distress syndrome (ARDS), leading to intubation, jaundice, alveolar bleeding and multi-organ failure. A 71-year-old male patient presented at the emergency department with dyspnea on exertion, fever, gastrointestinal disorders, muscle aches and fatigue, that started four days ago. Occupation with pigeons was also reported. Blood gas analysis revealed severe type I respiratory failure, and a chest CT was performed, revealing ARDS. The patient was intubated. Acute renal failure (urea: 238, creatinine: 4.81) that required renal replacement therapy developed along with increased bilirubin (max value of total: 8.2 with direct: 7.42), and positive direct and indirect Coombs test. Moreover, hemorrhage through the tracheal tube complicated the clinical condition, resulting to obstruction of tracheal tube. Furthermore, anemia, thrombocytopenia and severe leycocytosis were also observed (white blood cells: 42,620). Diffuse alveolar hemorrhage due to vasculitis and connective tissue disease was suspected, and a complete immunological control was ordered. Infectious pathogens, such as Str. Pneumoniae, Legionella, Mycoplasma, Leptospira spp., Chlamidia, HBV, HCV, influenza were also suspected and all the necessary samples were tested. He received levofloxacin, piperacillin/tazobactam, vibramycin, and oseltamivir, but after receiving the positive results for leptospira, antibiotic treatment was revised with the final choice of levofloxacin and piperacillin/tazobactam. Despite improvement of renal and liver function, leycocytosis, CRP and PCT values, high fever begun that was attributed at first to the Jarisch-Herxheimer syndrome. Some days after, pneumonia due to Acinetobacter baumannii was diagnosed and treated with colimyxin resulting to further improvement. The patient underwent tracheostomy but finally weaned from mechanical ventilation after 23 days and was discharged from the respiratory failure unit on the 26th day.

Pediatric Fulminant Leptospirosis Complicated by Pericardial Tamponade, Macrophage Activation Syndrome and Sclerosing Cholangitis.

Leptospirosis is a zoonotic infectious disease caused by pathogenic spirochetes of the genus Leptospira. Although it is usually asymptomatic and self-limited, severe potentially fatal illness accompanied by multi-organ failure may occur. Here we report an unusual case of severe leptospirosis successfully treated with continuous venovenous hemofiltration (CVVHF) and therapeutic plasma exchange (TPE). The patient presented with pericardial tamponade, renal failure and macrophage activation syndrome, and later suffered prolonged jaundice and sclerosing cholangitis during hospitalization in the pediatric intensive care unit (PICU). To the best of our knowledge, sclerosing cholangitis due to leptospirosis has not been reported in the literature. Leptospirosis should be kept in mind in the differential diagnosis of sepsis and septic shock with fever, thrombocytopenia, jaundice and renal failure. TPE and CVVHF should start early after the diagnosis of leptospirosis with multiorgan failure.

Leptospira Immunoglobulin-Like Protein B (LigB) Binds to Both the C-Terminal 23 Amino Acids of Fibrinogen αC Domain and Factor XIII: Insight into the Mechanism of LigB-Mediated Blockage of Fibrinogen α Chain Cross-Linking.

The coagulation system provides a primitive but effective defense against hemorrhage. Soluble fibrinogen (Fg) monomers, composed of α, β and γ chains, are recruited to provide structural support for the formation of a hemostatic plug. Fg binds to platelets and is processed into a cross-linked fibrin polymer by the enzymatic clotting factors, thrombin and Factor XIII (FXIII). The newly formed fibrin-platelet clot can act as barrier to protect against pathogens from entering the bloodstream. Further, injuries caused by bacterial infections can be confined to the initial wound site. Many pathogenic bacteria have Fg-binding adhesins that can circumvent the coagulation pathway and allow the bacteria to sidestep containment. Fg expression is upregulated during lung infection providing an attachment surface for bacteria with the ability to produce Fg-binding adhesins. Fg binding by leptospira might play a crucial factor in Leptospira-associated pulmonary hemorrhage, the main factor contributing to lethality in severe cases of leptospirosis. The 12th domain of Leptospira immunoglobulin-like protein B (LigB12), a leptospiral adhesin, interacts with the C-terminus of FgαC (FgαCC). In this study, the binding site for LigB12 was mapped to the final 23 amino acids at the C-terminal end of FgαCC (FgαCC8). The association of FgαCC8 with LigB12 (ELISA, KD = 0.76 μM; SPR, KD = 0.96 μM) was reduced by mutations of both charged residues (R608, R611 and H614 from FgαCC8; D1061 from LigB12) and hydrophobic residues (I613 from FgαCC8; F1054 and A1065 from LigB12). Additionally, LigB12 bound strongly to FXIII and also inhibited fibrin formation, suggesting that LigB can disrupt coagulation by suppressing FXIII activity. Here, the detailed binding mechanism of a leptospiral adhesin to a host hemostatic factor is characterized for the first time and should provide better insight into the pathogenesis of leptospirosis.

Leptospirosis: risk factors and management challenges in developing countries.

Leptospirosis is a widespread bacterial zoonosis with highest burden in low-income populations living in tropical and subtropical regions, both in urban and in rural environments. Rodents are known as the main reservoir animals, but other mammals may also significantly contribute to human infections in some settings. Clinical presentation of leptospirosis is nonspecific and variable, and most of the early signs and symptoms point to the so-called “acute fever of unknown origin”, a major diagnostic challenge in tropical and subtropical areas. However, leptospirosis can rapidly evolve to life-threatening complications, especially if left untreated. There is a need for good awareness of leptospirosis and rapid antibiotic treatment based on clinical and epidemiological suspicion. Severe leptospirosis cases include renal and/or respiratory failure and shock, necessitating intensive care, also seldom available or with limited capacity. Confirmation of leptospirosis relies on biological diagnosis, which unfortunately uses tricky methods seldom available. This biological confirmation, however, is essential for surveillance and public health purpose. A good knowledge of leptospirosis epidemiology (eg, the reservoir animals involved, the Leptospira strains circulating, the seasonal and geographical patterns, and specific populations at risk) can be achieved through adequate surveillance and diagnosis. This can pave the way to prevention and intervention strategies and in turn alleviate the toll leptospirosis takes on affected populations. Over the past few years, leptospirosis has been increasingly recognized, as the need for multidisciplinary approaches in a One-Health perspective has been acknowledged, raising hope to successfully tackle the challenges of this zoonosis.

Leptospira Seroprevalence in Capybaras from a Brazilian Urban Area

Background: Leptospirosis remains the most widespread zoonotic disease in the world. As a clinical entity it is strongly associated with regional occupational and environmental exposures. While the exact global disease burden remains unknown, recent estimates by the leptospirosis Burden Epidemiology Reference Group (LERG) at the World Health Organization have set the number of human cases of severe leptospirosis to over 500,000 per year. This number almost certainly represents an under-representation due to poor surveillance and difficult diagnosis. Leptospira spp. belong to the order Spirochaetales, family Leptospiraceae, composed by 13 pathogenic Leptospira species with more than 260 serovars. Wildlife species are commonly considered to be important epidemiological carriers, mainly because of their frequent reactivity to Leptospira serovars native to their habitat. Capybara (Hydrochaeris hydrochaeris), a known leptospirosis host, is a widespread species in South America. However, reports regarding the importance of this animal in the epidemiology of leptospirosis are rare. Therefore, the objective of this study was to report the results of leptospirosis serological survey of capybaras from a residential park area in southeastern Brazil.Materials, Methods & Results: A total of 172 capybaras were sampled at Itú Municipality, state of São Paulo, southeastern Brazil, from December 2012 to May 2013. Sera samples were examined for Leptospira antibodies by the microscopic agglutination test (MAT), using live antigens grown in liquid medium (EMJH). A complete panel of 7 serogroups (including 10 reference serovars) was used as antigens: serogroup Sejroe (serovars Hardjo and Wolffi), serogroup Grippotyphosa (serovar Grippotyphosa), serogroup Canicola (serovar Canicola), serogroup Icterohaemorrhagiae (serovars Icterohaemorrhagiae and Copenhageni), serogroup Australis (serovars Australis and Bratislava), serogroup Pomona (serovar Pomona), and serogroup Autumnalis (serovar Butembo). As a results, 46 (26.75%) were serologically positive: 29 (63.05%) for serogroup Sejroe, 7 (15.22%) for serogroup Icterohaemorrhagiae; 9 (19.56%) were seropositive for serogroups Sejroe and Icterohaemorrhagiae; and 1 (2.17%) was positive for serogroups Sejroe and Grippotyphosa.Discussion: L. interrogans sensu stricto is responsible for the most frequent and severe cases of human and animal leptospirosis. Considering the results of our serological survey, it is important to reinforce that in tropical countries, mainly Brazil, India, Thailand, Vietnam, Australia and Barbados, serovars belonging to the Icterohaemorrhagiae serogroup (Icterohaemorrhagiae and Copenhageni) are generally the most prevalent. Therefore, the report of different serogroups in capybaras (as observed in our study) it is an important observation reported. Human leptospirosis is usually due to serovars that are maintained by the animal populations of a region, which spread the bacterium on the environment; thus, it may represent an important additional risk factor for human population. Our study identified a greater serum reactivity to strains that belongs to serogroup Sejroe. In Brazil this serogroup is highly predominant in livestock; thus, our main hypothesis is that some animals were contaminated with Sejroe serovars when they were at their natural habitat and, once in the park, they maintained these serovars through cross transmission. Therefore, based on our results, it was possible to observe a significant prevalence of serovars belonging to serogroup Icterohaemorrhagiae, and there was also a high prevalence of samples positive to serogroup Sejroe. Thus, our serologic survey showed that capybaras living in an urban area could represent a risk factor for leptospirosis for the human population eventually exposed.