Acute kidney injury in emerging, non-tropical infections

Hantavirus Induced Kidney Disease

Hantavirus induced hemorrhagic fever with renal syndrome (HFRS) is an emerging viral zoonosis affecting up to 200,000 humans annually worldwide. This review article is focused on recent advances in the mechanism, epidemiology, diagnosis, and treatment of hantavirus induced HFRS. The importance of interactions between viral and host factors in the design of therapeutic strategies is discussed. Hantavirus induced HFRS is characterized by thrombocytopenia and proteinuria of varying severities. The mechanism of kidney injury appears immunopathological with characteristic deterioration of endothelial cell function and compromised barrier functions of the vasculature. Although multidisciplinary research efforts have provided insights about the loss of cellular contact in the endothelium leading to increased permeability, the details of the molecular mechanisms remain poorly understood. The epidemiology of hantavirus induced renal failure is associated with viral species and the geographical location of the natural host of the virus. The development of vaccine and antiviral therapeutics is necessary to avoid potentially severe outbreaks of this zoonotic illness in the future. The recent groundbreaking approach to the SARS-CoV-2 mRNA vaccine has revolutionized the general field of vaccinology and has provided new directions for the use of this promising platform for widespread vaccine development, including the development of hantavirus mRNA vaccine. The combinational therapies specifically targeted to inhibit hantavirus replication and vascular permeability in infected patients will likely improve the disease outcome.

Clinical and biochemical differences between hantavirus infection and leptospirosis: a retrospective analysis of a patient series in Belgium

Objectives: Hantavirus infection and leptospirosis are infectious diseases transmitted by rodents. The clinical picture is nonspecific, often involving the kidneys but other organs can be affected too. Clinical and biochemical clues to make a difference between these two entities will be described.Methods: A retrospective analysis was performed on a database of patients presenting between January 2012 and September 2017 at the emergency department of the university hospital Leuven, Belgium. Patients were selected on the basis of a compatible clinical picture, biochemistry, and microbiological evidence. Presenting complaints and clinical examination were compared. Blood, taken at presentation, was used for hematological and biochemical analysis.Results: Sixteen patients with hantavirus infection and eight patients with leptospirosis were identified. All patients complained about general malaise and fever. Other frequent complaints were myalgia and a headache. Patients with leptospirosis often experienced photo- or sonophobia.Looking for neck stiffness and eye lesions might help to diagnose leptospirosis.Differences in biochemistry between viral and bacterial disease could be recognized; high C-reactive protein (CRP) and leukocytosis with left shift favor leptospirosis, elevated lactate dehydrogenase (LDH) favors viral infection. Abnormal liver function with raised total bilirubin is often seen in cases with leptospirosis.Conclusion: This study demonstrates some subtle clues that may help to differentiate between hantavirus infection and leptospirosis in patients presenting to a hospital in a nonendemic region of the world. Because of small number of patients, we could not identify significant clinical or biochemical tests. Serology remains the gold standard.

Orthohantavirus pulmonary syndrome in Santa Cruz and Tarija, Bolivia, 2018

INTRODUCTION

Orthohantaviruses are still a significant public health threat in endemic countries, with high case fatality rates (CFR). In Bolivia, the reporting of small outbreaks occurred until 2012. The findings of 40 laboratory-confirmed cases diagnosed in two departments are reported herein.

METHODS

This was an observational, retrospective and cross-sectional study. Data on laboratory-confirmed cases in 2018 were collected from the hospitals and departmental health services (SEDES) of Santa Cruz and Tarija. An ELISA was used for the detection of IgM antibody to hantavirus in the patient blood samples.

RESULTS

Forty patients were IgM-positive. The median age of the patients was 24 years (interquartile range 19-41 years) and 72.5% were male. All patients were hospitalized; 57.5% were admitted to the intensive care unit and had cardiopulmonary compromise, with 83% of these presenting acute respiratory distress syndrome and 89.5% of these requiring mechanical ventilation. Six patients died (CFR 15%). Patients <15 or >60 years old were more prone to die (odds ratio 10.33, 95% confidence interval 1.411-75.694), as were those with comorbidities (odds ratio 16.5, 95% confidence interval 1.207-225.540).

CONCLUSIONS

Orthohantavirus infections were associated with a high CFR. These cases occurred in areas with eco-epidemiological conditions facilitating viral transmission, including the presence of rodents, as well as the risk of spillover to humans due to social, environmental, and occupational factors.

Hantavirus induced cardiopulmonary syndrome: A public health concern

Hantavirus cardiopulmonary syndrome is characterized by pulmonary capillary leakage and alveolar flooding, resulting in 50% mortality due to fulminant hypoxic respiratory failure. In addition, depression of cardiac function ensues, which complicates the picture with cardiogenic shock. Early diagnosis and appropriate use of extracorporeal membrane oxygenation (ECMO) are amongst the lifesaving interventions in this fatal illness. However, a recent case report demonstrates that implementation of high volume continuous hemofilteration along with protective ventilation reverses the cardiogenic shock within few hours in hantavirus infected patients. This review article is focused on the recent advances in clinical features, diagnosis, management, epidemiology, and pathogenesis of hantavirus induced cardiopulmonary syndrome. It provides information for clinicians to help in correct diagnosis during the early stages of viral infection that could improve the prognosis of this viral illness.

Assessment of bacterial diversity in Hyalomma aegyptium, H. marginatum and H. excavatum ticks through tag-encoded pyrosequencing

Ticks are among the most significant human-biting ectoparasites and they play a major role in transmission of many pathogenic agents to humans. In the present study, three species of Hyalomma ticks, Hyalomma aegyptium, H. marginatum and H. excavatum, were examined for the presence of zoonotic bacteria, both male and female ticks alike. Examination of microbial diversity with tag-encoded pyrosequencing indicates that H. marginatum and H. excavatum were more diversity rich than H. aegyptium. Although numerous pathogenic and non-pathogenic bacterial genera were detected, including Acidovorax, Bacillus, Bacteroides, Bdellovibrio, Clostridium, Curvibacter, Escherichia, Flavobacterium, Limnohabitans, Paenibacillus, Ralstonia, Sarcina, Sediminibacterium, Segetibacter Stenotrophomonas and Variovorax, the predominant zoonotic bacteria represented in these ticks were genera Borrelia, Francisella, and Rickettsia. To the authors' knowledge, this work represents the first detection of Yersinia enterocolitica in the tick H. excavatum, raising questions regarding the vector competency of this tick, as well as associations of different disease representations perhaps through previously unforeseen routes of pathogen introduction. Likewise, similar questions are related to the presence of Legionella pneumophila in one H. excavatum sample.

Acute hantavirus infection presenting as haemolytic-uraemic syndrome (HUS): the importance of early clinical diagnosis

The European prototype of hantavirus, Puumala virus (PUUV), isolated from a common wild rodent, the bank vole (Myodes glareolus), causes nephropathia epidemica (NE). NE can perfectly mimic haemolytic-uraemic syndrome (HUS), progressing from an aspecific flu-like syndrome to acute kidney injury with thrombocytopaenia, and presenting with some signs of haemolytic anaemia and/or coagulopathy. Moreover, both NE and HUS can occur in local outbreaks. We report an isolated case of NE, initially referred for plasmapheresis for suspected HUS, although signs of overt haemolysis were lacking. Early suspicion of hantavirus infection, later confirmed by serology and reverse transcription polymerase chain reaction (RT-PCR), prevented subsequent excessive treatment modalities.

Legionnaires' Disease Complicated with Rhabdomyolysis and Acute Kidney Injury in an AIDS Patient

Objective

To present a case of an uncommon triad of Legionella pneumonia, rhabdomyolysis, and renal failure, with review of the relevant literature.

Case

A 51-year-old with a history of human immunodeficiency virus (HIV), chronic obstructive pulmonary disease (COPD), and hypertension presented with fever, cough, and shortness of breath over four days. Chest X-ray showed consolidation in left lower lung field; urine was positive for Legionella antigen and myoglobin; creatine kinase was 51092U/L; creatine was 6.9 mg/dL, and his CD4 count was 41 cells/ul. He was managed with azithromycin and levofloxacin and further required dialysis and ventilatory support in the intensive care unit due to renal failure and respiratory failure. He responded well to the treatment and made a complete recovery. Legionella pneumophila infection is a recognized but rare cause of rhabdomyolysis with high morbidity and mortality when there is extrapulmonary involvement. Early diagnosis and appropriate treatment is essential to improve outcomes.

Conclusion

Physicians should consider Legionella pneumonia in patients with rhabdomyolysis, renal failure, and respiratory symptoms. Early diagnosis and treatment have been shown to have good clinical response. Timely intensive care management, together with early and judicious use of dialysis in patients complicated with rhabdomyolysis and renal failure, may lead to good outcomes.

Reservoir-Driven Heterogeneous Distribution of Recorded Human Puumala virus Cases in South-West Germany

Endemic regions for Puumala virus (PUUV) are located in the most affected federal state Baden-Wuerttemberg, South-West Germany, where high numbers of notified human hantavirus disease cases have been occurring for a long time. The distribution of human cases in Baden-Wuerttemberg is, however, heterogeneous, with a high number of cases recorded during 2012 in four districts (H districts) but a low number or even no cases recorded in four other districts (L districts). Bank vole monitoring during 2012, following a beech (Fagus sylvatica) mast year, resulted in the trapping of 499 bank voles, the host of PUUV. Analyses indicated PUUV prevalences of 7-50% (serological) and 1.8-27.5% (molecular) in seven of eight districts, but an absence of PUUV in one L district. The PUUV prevalence differed significantly between bank voles in H and L districts. In the following year 2013, 161 bank voles were trapped, with reduced bank vole abundance in almost all investigated districts except one. In 2013, no PUUV infections were detected in voles from seven of eight districts. In conclusion, the linear modelling approach indicated that the heterogeneous distribution of human PUUV cases in South-West Germany was caused by different factors including the abundance of PUUV RNA-positive bank voles, as well as by the interaction of beech mast and the proportional coverage of beech and oak (Quercus spec.) forest per district. These results can aid developing local public health risk management measures and early warning models.

Effect of temperature, relative humidity and rainfall on dengue fever and leptospirosis infections in Manila, the Philippines

Dengue fever (DF) and leptospirosis are serious public problems in tropical regions, especially in Manila, the Philippines. In attempting to understand the causes of DF and leptospirosis seasonality, meteorological factors have been suspected, but quantitative correlation between seasonality and meteorological factors has not been fully investigated. In this study, we investigated correlation of temporal patterns of reported numbers of laboratory-confirmed cases of both DF and leptospirosis with meteorological conditions (temperature, relative humidity, rainfall) in Manila. We used time-series analysis combined with spectral analysis and the least squares method. A 1-year cycle explained underlying variations of DF, leptospirosis and meteorological data. There was a peak of the 1-year cycle in temperature during May, followed by maxima in rainfall, relative humidity and number of laboratory-confirmed DF and leptospirosis cases. This result suggests that DF and leptospirosis epidemics are correlated not only with rainfall but also relative humidity and temperature in the Philippines. Quantifying the correlation of DF and leptospirosis infections with meteorological conditions may prove useful in predicting DF and leptospirosis epidemics, and health services should plan accordingly.

'Bedside assessment' of acute hantavirus infections and their possible classification into the spectrum of haemophagocytic syndromes

Hantavirus infections, recently renamed 'hantavirus fever' (HTVF), belong to the most common but also most underestimated zoonoses in the world. A small number of reports described the so-called 'lipid paradox' in HTVF, i.e. the striking contrast between a very low serum total cholesterol and/or high-density lipoprotein cholesterol (HDLc), and a paradoxical concomitant hypertriglyceridaemia. In a prospective study, with patients being their own control after illness, we wanted to verify if this quick and easy 'bedside test' was robust enough to warrant a preliminary diagnosis of acute kidney injury (AKI) caused by HTVF. The study cohort consisted of 58 Belgian cases (mean age 44 years), admitted with varying degrees of AKI and of thrombocytopaenia, both characteristic for presumptive HTVF. All cases were sero-confirmed as having acute HTVF. At or shortly after hospital admission, a significant (p < 0.001) decrease of total cholesterol and HDLc was found in comparison with normalised levels in the same cohort, quantified a few days after spontaneous AKI recovery. Conversely, fasting triglyceride levels during HTVF infection were significantly (p < 0.001) higher during illness than after recovery. This 'lipid paradox' was most outspoken in severe HTVF cases, often accompanying, or even predicting, major kidney or lung complications. Thus, this 'bedside assessment' seems to hold even promise for presumptive diagnosis of more severe so-called 'hantavirus cardio-pulmonary syndrome' (HCPS) cases, mostly described hitherto in the New World. In more severe AKI cases, the mean total cholesterol was significantly lower (p = 0.02) than in milder cases, i.e. cases with peak serum creatinine levels of < 1.5 mg/dL. Thrombocytopaenia, generally accepted as the severity index in HTVF, appeared, moreover, significantly correlated with serum levels of total cholesterol (R = 0.52, p < 0.001) and with serum levels of HDLc (R = 0.45, p < 0.01). A link with the novel clinical entity of haemophagocytic syndromes, also characterised by manifest hypertriglyceridaemia, is discussed.

Acalculous cholecystitis associated with hemorrhagic fever with renal syndrome

Hantaviruses are responsible for various types of hemorrhagic fevers depending on the involved subtype. In Europe, Puumala virus is responsible for an epidemic nephropathy. This infection can be complicated by severe abdominal pain. A rarely reported cause of this presenting symptom is acalculous cholecystitis, which must be integrated in the clinicobiological spectrum and should not lead to a surgical sanction. Its presence seems to be correlated with the severity of the disease, whose main pathophysiological phenomenon is plasma leakage induced by a microvascular endothelial dysfunction. We report the case of a young male patient who presented with severe hantavirus infection complicated by acalculous cholecystitis.

Concomitant leptospirosis-hantavirus co-infection in acute patients hospitalized in Sri Lanka: implications for a potentially worldwide underestimated problem

Two global (re-)emerging zoonoses, leptospirosis and hantavirus infections, are clinically indistinguishable. Thirty-one patients, hospitalized in Sri Lanka for acute severe leptospirosis, were after exclusion of other potentially involved pathogens, prospectively screened with IgM ELISA for both pathogens. Of these, nine (29·0%) were positive for leptospirosis only, one (3·2%) for hantavirus only, seven (22·5%) for both pathogens concomitantly, whereas 13 (41·9%) remained negative for both. Moreover, in a retrospective study of 23 former patients, serologically confirmed for past leptospirosis, six (26·0%) were also positive in two different IgG ELISA hantavirus formats. Surprisingly, European Puumala hantavirus (PUUV) results were constantly higher, although statistically not significantly different, than Asian Hantaan virus (HTNV), suggesting an unexplained cross-reaction, since PUUV is considered absent throughout Asia. Moreover, RT-PCR on all hantavirus IgM ELISA positives was negative. Concomitant leptospirosis-hantavirus infections are probably heavily underestimated worldwide, compromising epidemiological data, therapeutical decisions, and clinical outcome.

Wars, disasters and kidneys

This paper summarizes the impact that wars had on the history of nephrology, both worldwide and in the Ghent Medical Faculty notably on the definition, research and clinical aspects of acute kidney injury. The paper briefly describes the role of 'trench nephritis' as observed both during World War I and II, supporting the hypothesis that many of the clinical cases could have been due to Hantavirus nephropathy. The lessons learned from the experience with crush syndrome first observed in World War II and subsequently investigated over many decades form the basis for the creation of the Renal Disaster Relief Task Force of the International Society of Nephrology. Over the last 15 years, this Task Force has successfully intervened both in the prevention and management of crush syndrome in numerous disaster situations like major earthquakes.

Hemorrhagic Fever with Renal Syndrome in the New, and Hantavirus Pulmonary Syndrome in the Old World: paradi(se)gm lost or regained?

Since the first clinical description in 1994 of the so-called "Hantavirus Pulmonary Syndrome" (HPS) as a "newly recognized disease", hantavirus infections have always been characterized as presenting in two distinct syndromes, the so-called "Hemorrhagic Fever with Renal Syndrome" (HFRS) in the Old World, with the kidney as main target organ, in contrast to HPS in the New World, with the lung as main target organ. However, European literature mentions already since 1934 a mostly milder local HFRS form, aptly named "nephropathia epidemica" (NE), and caused by the prototype European hantavirus species Puumala virus (PUUV). Several NE reports dating from the 1980s and early 1990s described already non-cardiogenic HPS-like lung involvement, prior to any kidney involvement, and increasing evidence is now mounting that a considerable clinical overlap exists between HPS and HFRS. Moreover, growing immunologic insights point to common pathologic mechanisms, leading to capillary hyperpermeability, the cardinal feature of all hantavirus infections, both of the New and Old World. It is now perhaps time to reconsider the paradigm of two "different" syndromes caused by viruses of the same Hantavirus genus in the same Bunyaviridae family, and to agree on a common, more logical disease denomination, such as simply and briefly "Hantavirus fever".

Another case of "European hantavirus pulmonary syndrome" with severe lung, prior to kidney, involvement, and diagnosed by viral inclusions in lung macrophages

Puumala virus (PUUV) is considered a classic Old World etiologic agent of nephropathia epidemica (NE), or hemorrhagic fever with renal syndrome (HFRS). HFRS is considered to be distinct from hantavirus (cardio-)pulmonary syndrome (HPS or HCPS), described in the New World. Here, we report a severe case, which fulfilled most, if not all, Centers for Disease Control and Prevention (CDC) criteria for HPS, needing non-invasive ventilation and subsequent acute hemodialysis. However, the etiological agent was PUUV, as proved by serological testing, real-time polymerase chain reaction (PCR), and sequencing. Viral antigen was detected by specific anti-PUUV immunostaining, showing, for the first time, greenish intracytoplasmic inclusions in bronchoalveolar lavage (BAL) macrophages. This case definitely confirms that HPS can be encountered during PUUV infections. Interestingly, special findings could render the diagnosis easier, such as greenish homogeneous cytoplasmic inclusions, surrounded by a fine clear halo in BAL macrophages. Therefore, although the diagnosis remains difficult before the onset of renal involvement, the occurrence of severe respiratory failure mimicking community-acquired pneumonia must alert the clinician for possible HPS, especially in endemic areas.

Hantavirus nephropathy as a pseudo-import pathology from Ecuador

We report a case of hantavirus infection (nephropathia epidemica) diagnosed in a Belgian backpacker returning from a trekking expedition in Ecuador, after likely heavy exposure to rodents. Because of epidemiological inconsistency, molecular investigation was performed and revealed a Puumala infection acquired during very limited exposure in Belgium upon return.

Environmental and ecological potential for enzootic cycles of Puumala hantavirus in Great Britain

Puumala virus (PUUV) is a zoonotic rodent-borne hantavirus in continental Europe. Its reservoir host, the bank vole (Myodes glareolus), is ubiquitous in Great Britain (GB); however, there has been no reported incidence of virus in either animals or humans. In northwest Europe, increases in bank vole numbers, stimulated by increases in production of beech/oak crops (mast), are associated with outbreaks of nephropathia epidemica (NE) in humans. These so-called 'mast years' are determined by sequential climatic events. This paper investigates the contribution of a number of ecological and environmental factors driving outbreaks of PUUV in northwest Europe and assesses whether such factors might also permit enzootic PUUV circulation in GB. Analysis of GB climate data, using regression models, confirms that mast years in GB are stimulated, and can be predicted, by the same climatic events as mast years in PUUV-endemic regions of northwest Europe. A number of other possible non-climatic constraints on enzootic cycles are discussed.

Recent approaches in hantavirus vaccine development

Rodent-borne hantaviruses are associated with two main clinical disorders in humans: hemorrhagic fever with renal syndrome and hantavirus cardiopulmonary syndrome. Although hantavirus diseases can be life threatening and numerous research efforts are focused on the development of hantavirus prevention, no specific antiviral therapy is yet available and, at this time, no WHO-approved vaccine has gained widespread acceptance. This review will summarize the current knowledge and recent progress as well as new speculative approaches in the development of hantavirus vaccines.

Relating increasing hantavirus incidences to the changing climate: the mast connection

BACKGROUND

Nephropathia epidemica (NE), an emerging rodent-borne viral disease, has become the most important cause of infectious acute renal failure in Belgium, with sharp increases in incidence occurring for more than a decade. Bank voles are the rodent reservoir of the responsible hantavirus and are known to display cyclic population peaks. We tried to relate these peaks to the cyclic NE outbreaks observed since 1993. Our hypothesis was that the ecological causal connection was the staple food source for voles, being seeds of deciduous broad-leaf trees, commonly called "mast". We also examined whether past temperature and precipitation preceding "mast years" were statistically linked to these NE outbreaks.

RESULTS

Since 1993, each NE peak is immediately preceded by a mast year, resulting in significantly higher NE case numbers during these peaks (Spearman R = -0.82; P = 0.034). NE peaks are significantly related to warmer autumns the year before (R = 0.51; P < 0.001), hotter summers two years before (R = 0.32; P < 0.001), but also to colder (R = -0.25; P < 0.01) and more moist summers (R = 0.39; P < 0.001) three years before. Summer correlations were even more pronounced, when only July was singled out as the most representative summer month.

CONCLUSION

NE peaks in year 0 are induced by abundant mast formation in year-1, facilitating bank vole survival during winter, thus putting the local human population at risk from the spring onwards of year 0. This bank vole survival is further promoted by higher autumn temperatures in year-1, whereas mast formation itself is primed by higher summer temperatures in year-2. Both summer and autumn temperatures have been rising to significantly higher levels during recent years, explaining the virtually continuous epidemic state since 2005 of a zoonosis, considered rare until recently. Moreover, in 2007 a NE peak and an abundant mast formation occurred for the first time within the same year, thus forecasting yet another record NE incidence for 2008. We therefore predict that with the anticipated climate changes due to global warming, NE might become a highly endemic disease in Belgium and surrounding countries.