Massive pulmonary haemorrhage caused by leptospirosis successfully treated with nitric oxide inhalation and haemofiltration

Increased inflammation with crude E. coli LPS protects against acute leptospirosis in hamsters

Leptospirosis is a worldwide zoonotic disease that causes acute kidney injury, liver disease, bleeding disorders, and even death. Treatment of the disease is largely dependent on the use of antibiotics, but recent studies on pathogenesis of leptospirosis have shown that immunomodulation may also be an effective treatment for this disease. Since the delay in inflammation correlates with higher pathogenicity of leptospira, we studied the effect of inducing inflammation on leptospirosis by using TLR4 activator LPS. In accordance with our hypothesis, treatment with LPS protected against leptospirosis by enhancing the inflammatory response in hamsters. The gene expression levels of TLR2, TLR4, NLRP3 and inflammatory factors were higher in LPS-treated group during leptospira infection in hamsters. Although the levels of NO and iNOS were higher in LPS-treated group than in Leptospira-infected group, the protective effect induced by LPS is iNOS-independent. Treatment with LPS induced higher anti-leptospira IgG level than infection with leptospira alone. Then, expressions of costimulatory molecules and maturation markers were analysed. The data showed that treatment with LPS enhanced the expression of CD40, CD80 and CD86. Our results indicate that increased inflammation induced by LPS derived from Escherichia coli (E. coli) protects against leptospirosis in hamsters.

Role of Plasmapheresis and Extracorporeal Membrane Oxygenation in the Treatment of Leptospirosis Complicated with Pulmonary Hemorrhages

Introduction

Leptospirosis is an emerging infectious disease associated with multiorgan involvement and significant morbidity and mortality. Although pulmonary hemorrhage due to leptospirosis has a high fatality, specific treatment options are limited and their efficacy is not adequately proven. We opted to find out the current evidence on plasmapheresis and extracorporeal membrane oxygenation (ECMO) in pulmonary hemorrhages due to leptospirosis.

Methods

The first search was conducted in PubMed, OVID, Google Scholar, and Cochrane clinical trial registry using keywords "leptospirosis" OR "Leptospira" OR "Weil's disease" AND "plasmapheresis" OR "plasma exchange" AND "pulmonary hemorrhage" OR "alveolar hemorrhage" OR "lung hemorrhage" and the second search was done using keyword "leptospirosis" OR "Leptospira" OR "Weil's disease" AND "ECMO" OR "Extracorporeal membrane oxygenation." The searches were not limited by study design or the date of publication. Only articles written in English were reviewed. Although we intended to include only clinical trials, it was decided later to include other information such as case reports and case series which addressed these treatment modalities. Two authors selected articles independently in a blinded manner using a set of inclusion and exclusion criteria and discrepancies were solved after discussions.

Results

The information found was very limited. This included one clinical trial which showed a significant survival benefit with plasmapheresis but the study design had many limitations. Two case reports described the benefit of plasmapheresis in severe leptospirosis with pulmonary hemorrhages. There were eight case reports where ECMO was performed and out of all only one patient has died. One retrospective study on patients with severe leptospirosis mentioned that four out of five patients with pulmonary hemorrhages survived after being treated with ECMO.

Conclusions

Current evidence is insufficient to recommend the routine use of plasmapheresis or ECMO for patients presenting with pulmonary hemorrhages due to leptospirosis. ECMO may be a promising mode of treatment in acute respiratory failure in leptospirosis related pulmonary hemorrhages. These treatment modalities, however, can be applied based on the availability of resources and expertise at the discretion of the clinician in charge, considering patient related factors such as cardiovascular stability and derangement of coagulation profile. Clinical trials conducted adhering to standard procedures are urgently required to establish the efficacy of these treatment modalities.

Acute Respiratory Distress Syndrome Manifested by Leptospirosis Successfully Teated by Extracorporeal Membrane Oxygenation (ECMO)

Leptospirosis is recognized as a zoonotic disease that is emerging worldwide. Severe manifestations are associated with high morbidity and mortality rates and may therefore pose an important risk to public health, especially in certain high prevalence areas like Taiwan. The severe pulmonary form of leptospirosis is a lesser known entity and is characterized by intra-alveolar hemorrhage and can lead to acute respiratory failure with resistant hypoxemia, which leads to high mortality rates despite maximally invasive mechanical ventilation and adequate treatment. We herein present a case of severe leptospirosis complicated by massive pulmonary hemorrhage, which was successfully managed by extra corporeal membrane oxygenation.

Pulmonary manifestations of leptospirosis

Leptospirosis has a spectrum of presentation which ranges from mild disease to a severe form comprising of jaundice and renal failure. Involvement of the lung can vary from subtle clinical features to deadly pulmonary hemorrhage and acute respiratory distress syndrome. Of late, it has been identified that leptospirosis can present atypically with predominant pulmonary manifestations. This can delay diagnosis making and hence optimum treatment. The purpose of this review is to bring together all the reported pulmonary manifestations of leptospirosis and the recent trends in the management.

The emergence of severe pulmonary hemorrhagic leptospirosis: questions to consider

Since the 1980s, the incidence of severe pulmonary hemorrhage caused by Leptospira spp. infection has increased. The mild, non-specific symptoms or the more classical form of severe disease with hepatorenal manifestations, Weil's syndrome, predominate world-wide. However, several regions of the world have seen increases in numbers of patients with pulmonary hemorrhage attributed to leptospirosis. The reasons behind the emergence of this syndrome, which carries a high mortality rate, are not known. Several avenues for future research may shed light on the mechanisms involved in development of pulmonary hemorrhage, and inform targeted therapeutics to improve outcomes. Possibilities to consider include: (1) emergence of new bacterial strains, (2) acquisition of virulence traits by strains in the endemic regions, (3) changes in underlying health of the affected human populations, and (4) increased recognition of the syndrome and better record keeping by the medical and veterinary communities. Determining the causes of emerging clinical manifestations presents challenges and opportunities for potentially life-saving research into the pathogenesis of a number of infectious diseases, including leptospirosis.

Acute Renal Failure Due to Leptospirosis in a Renal Transplant Recipient: A Brief Review of the Literature

We present the case of a 43-year-old renal transplant patient who presented with fever, malaise, pruritus, headache, and severe jaundice of 3-week duration following work in a rice field. He was found to have acute renal failure and severe hyperbilirubinemia with a positive serum leptospira antibody titer, making the diagnosis of Weil's disease. The patient responded to reduction in immunosuppressive medications and intravenous penicillin therapy with no need for dialysis. This is the second case of leptospirosis in a kidney transplant patient reported in the English literature.

Optimal treatment of leptospirosis: queries and projections

Although the global burden of leptospirosis remains enormous and new aspects of the disease are constantly recognised, little progress has been achieved in the field of leptospirosis therapeutics and queries regarding the utility of antibiotics in the late severe form of the disease remain. From the currently existing data, conclusions on the efficacy of antibiotic administration in severe or late disease cannot easily be drawn, since clinical trials have different selection criteria and may focus on Leptospira serovars with different virulence. However, as a rule the benefit of the doubt should apply. Moreover, new options, such as ceftriaxone, have a superior safety profile to penicillin. In vitro studies have outlined potential antimicrobial candidates such as macrolides and ketolides. Development of a globally accepted subunit vaccine for humans is warranted but is not expected in the near future.

Immunoprotection of recombinant leptospiral immunoglobulin-like protein A against Leptospira interrogans serovar Pomona infection

We previously reported the cloning and characterization of leptospiral immunoglobulin-like proteins LigA and LigB of Leptospira interrogans. LigA and LigB are conserved at the amino-terminal region but are variable at the carboxyl-terminal region. Here, we evaluate the potential of recombinant LigA (rLigA) as a vaccine candidate against infection by L. interrogans serovar Pomona in a hamster model. rLigA was truncated into conserved (rLigAcon) and variable (rLigAvar) regions and expressed in Escherichia coli as a fusion protein with glutathione-S-transferase (rLigA). Golden Syrian hamsters were immunized at 3 and 6 weeks of age with rLigA (rLigAcon and rLigAvar) with aluminum hydroxide as an adjuvant. Hamsters given recombinant glutathione-S-transferase (rGST)-adjuvant and phosphate-buffered saline-adjuvant served as nonvaccinated controls. Three weeks after the last vaccination, all animals were challenged intraperitoneally with 10(8) L. interrogans serovar Pomona bacteria (NVSL 1427-35-093002). All hamsters immunized with recombinant LigA survived after challenge and had no significant histopathological changes. In contrast, nonimmunized and rGST-immunized hamsters were subjected to lethal doses, and the hamsters that survived showed severe tubulointerstitial nephritis. All vaccinated animals showed a rise in antibody titers against rLigA. Results from this study indicate that rLigA is a potential vaccine candidate against L. interrogans serovar Pomona infection.

Leptospirosis in the tropics and in travelers

Leptospirosis, caused by spirochetes of the genus Leptospira, has increasingly been recognized to affect travelers and residents in tropical settings. A zoonotic disease, leptospirosis is transmitted to humans through environmental surface waters contaminated by the urine of chronically infected mammals. Outcome of infection varies, ranging from acute febrile illness (including self-resolving undifferentiated fever) to aseptic meningitis to a fulminant syndrome of jaundice, oliguric renal failure, pulmonary hemorrhage, and refractory shock. Hospitalized cases have mortality rates as high as 25%. A recent clinical trial showed that third-generation cephalosporin is as effective as doxycycline and penicillin in the treatment of acute disease. Doxycycline is effective in preventing leptospirosis in travelers. No protective vaccine is currently available.

Haemodynamics in leptospirosis: Effects of plasmapheresis and continuous venovenous haemofiltration

BACKGROUND

Haemodynamics in leptospirosis may differ from that of sepsis because of frequently obeserved myocarditis and severe cholestatic jaundice. A haemodynamic study was therefore made in 10 patients with severe leptospirosis.

METHODS AND RESULTS

All patients had pulmonary complications with a chest X-ray showing either pulmonary oedema or infiltration. Renal failure was present in nine patients. Three patterns of haemodynamics were revealed. The first pattern was observed in six patients who showed increased cardiac index, decreased systemic vascular resistance, normal pulmonary capillary wedge pressure, normal pulmonary vascular resistance and hypotension. The pattern resembled that of sepsis. The second pattern shown in two patients with haemoptysis consisted of a normal cardiac index, normal systemic vascular resistance, normal blood pressure, normal pulmonary capillary wedge pressure and increased pulmonary vascular resistance. The third pattern was observed in two patients with severe jaundice who had hypotension, a relatively low cardiac index, increased systemic vascular resistance and normal pulmonary capillary wedge pressure, and pulmonary vascular resistance. Plasmapheresis performed in two patients and continuous venovenous haemofiltration performed in two patients improved systemic haemodynamics and normalized blood pressure with a resolution of lung signs.

Leptospirosis: a case report of a patient with pulmonary haemorrhage successfully managed with extra corporeal membrane oxygenation

Leptospirosis is a zoonosis of worldwide significance. Pulmonary involvement is common but often mild and of little clinical significance. However, over the last two decades an increasing number of cases have been reported with pulmonary haemorrhage as a prominent feature [Carvalho CR, Bethlem EP. Pulmonary complications of leptospirosis. Clin Chest Med, 2002;23(2):469-78]. These cases are particularly challenging to treat as they often have resistant hypoxaemia despite maximal invasive mechanical ventilation. Consequently, there is a high mortality rate. Here, we present a case of severe leptospirosis complicated by massive pulmonary haemorrhage which was successfully managed by extra corporeal membrane oxygenation (ECMO).

Prevention and treatment of leptospirosis

Leptospirosis is a common zoonosis acquired by exposure to body fluids, to tissues of infected animals, or to contaminated soil or fresh water. Large outbreaks of leptospirosis have occurred following excess rainfall or in tourists following exposure to fresh water during adventure activities. Prevention may be achieved through the use of protective clothing or by changes in animal husbandry. Immunization is not widely used in human populations but has a role in agriculture. Oral administration of doxycycline (Periostat , CollaGenex) once-weekly can give short-term protection in high-risk environments. The disease in humans has a broad range of symptoms. Treatment may be symptomatic or may require administration of antibiotics, such as doxycycline or penicillin.

The management of leptospirosis

How to quickly identify patients who should be treated for leptospirosis is a challenge. The interest of polymerase chain reaction (PCR) assays is currently being evaluated and rapid tests which can be used outside of the specialised laboratory, have recently been developed. Leptospires are sensitive to many antibiotics and few clinical studies have been made to compare different treatment options. Doxycycline is standard therapy in early leptospirosis treatment and chemoprophylaxis. Intravenous penicillin has been considered the drug of choice in late and severe disease, although it is now challenged by ceftriaxone, which use is easier. Ciprofloxacin may be combined with standard therapy in uveitis. Adjunctive therapies proposed in the management of severe forms of leptospirosis and Jarisch-Herxheimer reactions, are reviewed.

Hypoxia from vasculitic pulmonary haemorrhage improved by prone position ventilation

Ventilation in the prone position is used in patients with acute respiratory distress syndrome (ARDS), although data supporting this strategy are limited, and benefit for patients with other conditions is unclear. The patient in this report had severe hypoxaemia from diffuse alveolar haemorrhage caused by vasculitis with positive antineutrophil cytoplasmic antibodies (ANCA). Ventilation in the prone position improved oxygenation dramatically. This improvement was initially maintained when returned supine, accompanied by increased ventilation. Prone ventilation was used on three consecutive days for 10, 14 and 15 h, respectively. Prone ventilation could improve oxygenation by better ventilation-perfusion (V/Q) matching and improved drainage of blood from the dorsal lung. The improved oxygenation in this patient should encourage the use of prone ventilation in other patients with pulmonary haemorrhage and severe hypoxia.

Leptospiral nephropathy

Renal involvement is common in leptospirosis. Clinical manifestations vary from urinary sediment changes to acute renal failure. Renal failure is observed in 44% to 67% of patients. Hypokalemia frequently occurs. Severe hypotension is an important warning sign for the later development of renal and pulmonary complications. Prognosis of the disease is generally good except for its association with pulmonary complications, especially pulmonary hemorrhage and acute respiratory distress syndrome. Interstitial nephritis is the basic renal lesion. Vasculitis is observed in the acute phase of the disease. Tubular necrosis and interstitial nephritis are responsible for renal failure. Glomerular changes usually are not remarkable. Hemodynamic alterations, immune response, and direct nephrotoxicity are responsible for the development of renal lesions. As in many infectious diseases, decreased renal blood flow and glomerular filtration rate play a basic role. Bacterial invasion and toxicity of outer membrane with generation of cytokines, chemokines, and cellular infiltration are important in cellular injury.

Pulmonary complications of leptospirosis

Leptospirosis is a worldwide disease. In this time of globalization knowledge about leptospirosis is important. Although pulmonary involvement has an incidence varying from 20% to 70% and its exteriorization may vary from mild to severe, The severe form appears to be becoming more prevalent (at least in Brazil) and may be associated with higher mortality.

Hypotension, renal failure, and pulmonary complications in leptospirosis

During a recent outbreak of leptospirosis in northeastern Thailand, 148 patients with serologically diagnosed leptospirosis were seen in Loei hospital. The common serotypes were L. pyrogenes, and L. sejroe. Hypotension with a mean arterial pressure less than 70 mmHg upon admission or within 24 h after admission was observed in 94 patients or 64%. 30 patients had normal renal function; 30 patients had prerenal azotemia with mild pulmonary complication in 2; and 34 patients had acute renal failure. 29 patients with acute renal failure had pulmonary complications including pulmonary hemorrhage in 8, pulmonary edema in 3, acute respiratory distress syndrome (ARDS) in 14 and interstitial pneumonitis in 4. 54 patients had normal blood pressure. In this group 5 patients had acute renal failure; 16 had prerenal azotemia and 33 had normal renal function. Interstitial pneumonitis was noted in one patient with prerenal azotemia. Less renal complication and minimal pulmonary complication were seen in leptospirosis patients with normal blood pressure. The patients with normal renal function had no pulmonary complication. Good association existed between hypotension, renal failure and pulmonary complications.

Leptospirosis

Leptospirosis is a globally important zoonotic disease that affects humans on all continents, in both urban and rural contexts, and in temperate and tropical climes. Leptospirosis is a disease of the environment; transmission depends on interactions between humans and mammalian reservoir hosts. A variety of infectious diseases that present as undifferentiated febrile syndromes, such as malaria, dengue and influenza, as well as viral hemorrhagic fevers can mimic leptospirosis. The importance of pulmonary hemorrhage as a lethal complication of leptospirosis has become more widely recognized. In contrast to textbook dogma, population-based studies indicate that there is a poor correlation between infecting leptospiral strain and clinical expression of disease. Genetic transformation of a Leptospira sp. has now been reported, which should allow for detailed analysis of a variety of leptospiral genes. Publication of the whole Leptospira genome is eagerly awaited. Following recent reports of a new, highly effective conjugate typhoid vaccine, new efforts to find leptospirosis vaccines should include the manufacture and testing of conjugate leptospiral lipopolysaccharide vaccines. Recent advances, particularly in epidemiology, molecular genetics and pathogenesis, are placing leptospirosis at the cutting edge of biomedical science.

Pulmonary leptospirosis

Leptospirosis is a worldwide zoonosis affecting wild and domestic mammals. It is most commonly transmitted to humans by indirect contact with infected animals. Vascular injury, mainly capillary damage, and hemorrhagic diathesis are prominent features in the affected organs. The most severe form of the disease presents with high fever, intense jaundice, hemorrhagic diathesis, hepatic and renal dysfunction, mental status changes, and cardiovascular collapse. Focal or diffuse areas containing alveoli filled with erythrocytes characterize the pulmonary involvement. These latter conditions, although unusual, are associated with significant mortality.

Overview of the epidemiology, microbiology, and pathogenesis of Leptospira spp. in humans

Leptospirosis is probably the world's most widespread zoonosis. It remains underdiagnosed largely due to the broad spectrum of signs and symptoms attributable to this spirochetal pathogen. Leptospira spp. cause a diversity of diseases from flu-like illness to Weil's syndrome with multi-organ failure. Recent epidemics may herald a change in virulence or an alteration in the balance between humans and their interactions with other host species and the environment.