Leptospirosis-Associated Severe Pulmonary Hemorrhagic Syndrome with Lower Back Pain as an Initial Symptom

Prevalence of leptospirosis among patients attending renal and general outpatient clinics in Mulago Hospital, Kampala, Uganda

In this study, we sought to establish the prevalence of leptospirosis among renal patients and general outpatients attending Mulago National Referral Hospital, Uganda. A total of 254 patients were recruited, their blood samples collected and interviewer-administered semi-structured questionnaires provided between July and October 2018. These questionnaires captured data on sociodemographic characteristics and symptoms of leptospirosis disease. An individual with an average body temperature of 37.3 ± 1.1 °C was considered to be having fever. The blood samples were analyzed using the standard Microscopic Agglutination Test (MAT) with a panel of 14 Leptospira-serovars belonging to 11 serogroups. Prevalence was reported with confidence intervals while questionnaire data was analyzed using logistic regression analysis. We present an overall prevalence of leptospirosis at 4.70% (95% CI = 2.60-8.30) after analysis of samples from recruited patients. This seropositivity (12/254) was classified into 7 serovars, among which, Canicola and Djasiman presented with titers between ≥ 200 and ≥ 400 in samples of both renal patients and outpatients, indicative of the active disease. Djasiman was the highest contributor to the reported prevalence. Overall, most examined participants presented with common symptoms of abdominal pain (AOR = 24.4, 95% CI (2.42-267.89), p = 0.02) and dehydration (AOR = 0.1, 95% CI (0.01-0.69), p = 0.05). Our study suggests that these symptoms and previous history of abdominal pain may be caused by Leptospira infections among the studied participants. We therefore recommend inclusion of leptospirosis in the differential diagnosis for renal and febrile illnesses. Indeed, abdominal pain and dehydration should be further studied with a bigger sample size and for other related febrile illnesses.

Preliminary Characterization of Dog Derived Pathogenic Strains of Leptospira interrogans Serovar Australis in Nanchang of Jiangxi Province, China

Leptospirosis is a global zoonotic disease caused by pathogenic Leptospira, and those infected animals will show a variety of clinical symptoms and even death. The discovery of endemic strains is crucial to produce effective vaccines. In this study, we report that a strain of Leptospira, isolated from a dog, is pathogenic. Using MLST analysis, the serovar of isolated Leptospira was identified and found it belongs to Leptospira interrogation Serovar Australis. Then, the virulence of this strain was researched by using hamsters. After infection, all the hamsters died within 4-5 days. Typical pathological changes were found in the liver, kidney, and lung of hamsters. These results all indicated that the isolated Leptospira was pathogenic. Thus, this study facilitates to identifying local Leptospira strains and develop a more targeted canine Leptospira vaccine.

Leptospirosis: Molecular trial path and immunopathogenesis correlated with dengue, malaria and mimetic hemorrhagic infections

Immuno-pathogenesis of leptospirosis can be recounted well by following its trail path from entry to exit, while inducing disastrous damages in various tissues of the host. Dysregulated, inappropriate and excessive immune responses are unanimously blamed in fatal leptospirosis. The inherent abilities of the pathogen and inabilities of the host were debated targeting the severity of the disease. Hemorrhagic manifestation through various mechanisms leading to a fatal end is observed when this disease is unattended. The similar vascular destructions and hemorrhage manifestations are noted in infections with different microbes in endemic areas. The simultaneous infection in a host with more than one pathogen or parasite is referred as the coinfection. Notably, common endemic infections such as leptospirosis, dengue, chikungunya, and malaria, harbor favorable environments to flourish in similar climates, which is aggregated with stagnated water and aggravated with the poor personal and environmental hygiene of the inhabitants. These factors aid the spread of pathogens and parasites to humans and potential vectors, eventually leading to outbreaks of public health relevance. Malaria, dengue and chikungunya need mosquitoes as vectors, in contrast with leptospirosis, which directly invades human, although the environmental bacterial load is maintained through other mammals, such as rodents. The more complicating issue is that infections by different pathogens exhibiting similar symptoms but require different treatment management. The current review explores different pathogens expressing specific surface proteins and their ability to bind with array of host proteins with or without immune response to enter into the host tissues and their ability to evade the host immune responses to invade and their affinity to certain tissues leading to the common squeal of hemorrhage. Furthermore, at the host level, the increased susceptibility and inability of the host to arrest the pathogens' and parasites' spread in different tissues, various cytokines accumulated to eradicate the microorganisms and their cellular interactions, the antibody dependent defense and the susceptibility of individual organs bringing the manifestation of the diseases were explored. Lastly, we provided a discussion on the immune trail path of pathogenesis from entry to exit to narrate the similarities and dissimilarities among various hemorrhagic fevers mentioned above, in order to outline future possibilities of prevention, diagnosis, and treatment of coinfections, with special reference to endemic areas.