Leptospirosis pathophysiology: Difference between revisions

Jump to navigation Jump to search
(Category)
No edit summary
Line 1: Line 1:
__NOTOC__
__NOTOC__
[[File:Rat.jpg|right|200px]]
{{Leptospirosis}}
{{Leptospirosis}}
{{CMG}}; {{AE}}{{VSKP}}
{{CMG}}; {{AE}}{{VSKP}}
Line 8: Line 7:
==Pathogenesis==
==Pathogenesis==
The disease [[leptospirosis]] involves a spectrum of symptoms ranging from subclinical infection to a severe syndrome of multiorgan infection with high mortality and Weil’s disease represents only the most severe presentation. Severe leptospirosis is frequently caused by serovars of the icterohaemorrhagiae serogroup. The presentation of leptospirosis is biphasic, with the acute or septicemic phase lasting about a week, followed by the immune phase, characterized by antibody production and excretion of leptospires in the urine.<ref name="Levett2001">{{cite journal|last1=Levett|first1=P. N.|title=Leptospirosis|journal=Clinical Microbiology Reviews|volume=14|issue=2|year=2001|pages=296–326|issn=0893-8512|doi=10.1128/CMR.14.2.296-326.2001}}</ref>
The disease [[leptospirosis]] involves a spectrum of symptoms ranging from subclinical infection to a severe syndrome of multiorgan infection with high mortality and Weil’s disease represents only the most severe presentation. Severe leptospirosis is frequently caused by serovars of the icterohaemorrhagiae serogroup. The presentation of leptospirosis is biphasic, with the acute or septicemic phase lasting about a week, followed by the immune phase, characterized by antibody production and excretion of leptospires in the urine.<ref name="Levett2001">{{cite journal|last1=Levett|first1=P. N.|title=Leptospirosis|journal=Clinical Microbiology Reviews|volume=14|issue=2|year=2001|pages=296–326|issn=0893-8512|doi=10.1128/CMR.14.2.296-326.2001}}</ref>
[[File:Leptospirosis pathogenesis.jpg|center]]
=== Reservoirs ===
=== Reservoirs ===
The major reservoir for leptospirosis is rat and small rodents that appear to harbour more virulent strains of the disease.<ref name="Picardeau2013">{{cite journal|last1=Picardeau|first1=M.|title=Diagnosis and epidemiology of leptospirosis|journal=Médecine et Maladies Infectieuses|volume=43|issue=1|year=2013|pages=1–9|issn=0399077X|doi=10.1016/j.medmal.2012.11.005}}</ref>
The major reservoir for leptospirosis is rat and small rodents that appear to harbour more virulent strains of the disease.<ref name="Picardeau2013">{{cite journal|last1=Picardeau|first1=M.|title=Diagnosis and epidemiology of leptospirosis|journal=Médecine et Maladies Infectieuses|volume=43|issue=1|year=2013|pages=1–9|issn=0399077X|doi=10.1016/j.medmal.2012.11.005}}</ref>

Revision as of 00:13, 26 September 2017

Leptospirosis Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Leptospirosis from other Diseases

Epidemiology and Demographics

Risk Factors

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

Other Imaging Findings

Treatment

Medical Therapy

Surgery

Primary Prevention

Future or Investigational Therapies

Case Studies

Case #1

Leptospirosis pathophysiology On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Leptospirosis pathophysiology

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Leptospirosis pathophysiology

CDC on Leptospirosis pathophysiology

Leptospirosis pathophysiology in the news

Blogs on Leptospirosis pathophysiology

Directions to Hospitals Treating Leptospirosis

Risk calculators and risk factors for Leptospirosis pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Venkata Sivakrishna Kumar Pulivarthi M.B.B.S [2]

Overview

Leptospires shed in the urine of animals to the environment from where humans are infected by incidental hosts. In Carriers these bacteria harbor in the renal tubules and can persist in soil or surface water and then transmits to human hosts via mucous membranes or abraded skin.[1][2] Pathogen transmit through various mechanisms such as broken skin, mucus membranes and the conjunctivae, exposure to contaminated water are at risk of contracting leptospirosis.[3]

Pathogenesis

The disease leptospirosis involves a spectrum of symptoms ranging from subclinical infection to a severe syndrome of multiorgan infection with high mortality and Weil’s disease represents only the most severe presentation. Severe leptospirosis is frequently caused by serovars of the icterohaemorrhagiae serogroup. The presentation of leptospirosis is biphasic, with the acute or septicemic phase lasting about a week, followed by the immune phase, characterized by antibody production and excretion of leptospires in the urine.[4]

Reservoirs

The major reservoir for leptospirosis is rat and small rodents that appear to harbour more virulent strains of the disease.[5]

Carriers

Domestic animals such as dogs,cattle and pigs acts as potential carriers that increases the risk of leptospirosis in humans. These carriers are generally asymptomatic.[6][7]

Modes of transmission

  1. Direct contact with urine or tissue of infected animal: Through skin abrasions and intact mucus membrane
  2. Indirect contact: Broken skin with infected soil, water or vegetation, Through ingestion of contaminated food and water
  3. Droplet infection: Inhalation of droplets of infected urine

Infection can occurs either by direct contact with the carrier’s urine or through indirect transmission via urine-contaminated environment. Infection due to direct transmission through direct oral intake of contaminated drinking water or food is very rare.[8] Pathogenic leptospires live in the renal system and the genital tracts of domestic animals which act as sites of persistence.[9][10] Bacteria shed from the infected animals such as rodents and domesticat animals through urine. These animals may not show signs of disease but humans shows signs of illness after contact with infected urine, or through contact with water, soil or food that has been contaminated and the outbreaks are associates with floodwaters. The major route of infection by leptospires is probably by transmission through indirect contact with leptospires secreted into the environment. Humans are considered dead end hosts, but sometimes they also act as carriers. Mammalian species (e.g. rodents, insectivores, dogs, pigs and cattle) act as the main carriers of the disease.[11] Leptospires are excreted in urine into the environment, where they can survive for several months, depending on favourable environmental conditions such as humid and temperate areas. The pathogen may also be excreted in the products of abortion in mammalian animal species.[9]

Pathological findings of leptospirosis are due to the development of the following:[12][13][14][15]

Leptospira

Toxin production

Type of toxin production depends on the serovar

Damage to small blood vessels

Vasculitis

• Direct cytotoxic injury or Immunological injury
• Fluid extavasation into the interstitial compartment due to vasculitis

Acute renal injury and vascular injury to internal organs

Gross Pathology

Gross findings of various organ systems are present as:[16]

  • Extensive petechial hemorrhages are common.
  • Discoloration of organs is seen in severe cases of icteric leptospirosis.

Microscopic Pathology

Liver

Kidney

Heart

Leptospirosis is associate with interstitial myocarditis.[20][21][22][23]

Lungs

Common pulmonary presentation in leptospirosis are pulmonary congestion and hemorrhage.[16][23][24][25]

Skeletal muscle

Brain

References

  1. BABUDIERI B (1958). "Animal reservoirs of leptospires". Ann N Y Acad Sci. 70 (3): 393–413. PMID 13559904.
  2. Forbes, A. E.; Zochowski, W. J.; Dubrey, S. W.; Sivaprakasam, V. (2012). "Leptospirosis and Weil's disease in the UK". QJM. 105 (12): 1151–1162. doi:10.1093/qjmed/hcs145. ISSN 1460-2725.
  3. Forbes AE, Zochowski WJ, Dubrey SW, Sivaprakasam V (2012). "Leptospirosis and Weil's disease in the UK". QJM. 105 (12): 1151–62. doi:10.1093/qjmed/hcs145. PMID 22843698.
  4. Levett, P. N. (2001). "Leptospirosis". Clinical Microbiology Reviews. 14 (2): 296–326. doi:10.1128/CMR.14.2.296-326.2001. ISSN 0893-8512.
  5. Picardeau, M. (2013). "Diagnosis and epidemiology of leptospirosis". Médecine et Maladies Infectieuses. 43 (1): 1–9. doi:10.1016/j.medmal.2012.11.005. ISSN 0399-077X.
  6. Gaudie CM, Featherstone CA, Phillips WS, McNaught R, Rhodes PM, Errington J; et al. (2008). "Human Leptospira interrogans serogroup icterohaemorrhagiae infection (Weil's disease) acquired from pet rats". Vet Rec. 163 (20): 599–601. PMID 19011247.
  7. Strugnell BW, Featherstone C, Gent M, Lister P, Evans G, Okereke E; et al. (2009). "Weil's disease associated with the adoption of a feral rat". Vet Rec. 164 (6): 186. PMID 19202179.
  8. Cacciapuoti B, Ciceroni L, Maffei C, Di Stanislao F, Strusi P, Calegari L; et al. (1987). "A waterborne outbreak of leptospirosis". Am J Epidemiol. 126 (3): 535–45. PMID 3618584.
  9. 9.0 9.1 Ellis WA, O'Brien JJ, Cassells JA, Neill SD, Hanna J (1985). "Excretion of Leptospira interrogans serovar hardjo following calving or abortion". Res Vet Sci. 39 (3): 296–8. PMID 4081333.
  10. Ellis WA, McParland PJ, Bryson DG, Thiermann AB, Montgomery J (1986). "Isolation of leptospires from the genital tract and kidneys of aborted sows". Vet Rec. 118 (11): 294–5. PMID 3705357.
  11. Ganoza CA, Matthias MA, Saito M, Cespedes M, Gotuzzo E, Vinetz JM (2010). "Asymptomatic renal colonization of humans in the peruvian Amazon by Leptospira". PLoS Negl Trop Dis. 4 (2): e612. doi:10.1371/journal.pntd.0000612. PMC 2826405. PMID 20186328.
  12. Budihal, Suman Veerappa (2014). "Leptospirosis Diagnosis: Competancy of Various Laboratory Tests". JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH. doi:10.7860/JCDR/2014/6593.3950. ISSN 2249-782X.
  13. BEESON PB, HANKEY DD (1952). "Leptospiral meningitis". AMA Arch Intern Med. 89 (4): 575–83. PMID 14902167.
  14. King SD, Urquhart AE (1975). "Laboratory investigations on four cases of leptospiral meningitis in Jamaica". West Indian Med J. 24 (4): 196–201. PMID 1224630.
  15. Silva MV, Camargo ED, Batista L, Vaz AJ, Ferreira AW, Barbosa PR (1996). "Application of anti-leptospira ELISA-IgM for the etiologic elucidation of meningitis". Rev Inst Med Trop Sao Paulo. 38 (2): 153–6. PMID 9071036.
  16. 16.0 16.1 16.2 16.3 AREAN VM (1962). "The pathologic anatomy and pathogenesis of fatal human leptospirosis (Weil's disease)". Am J Pathol. 40: 393–423. PMC 1949541. PMID 13862141.
  17. De Brito T, Machado MM, Montans SD, Hoshino S, Freymüller E (1967). "Liver biopsy in human leptospirosis: a light and electron microscopy study". Virchows Arch Pathol Anat Physiol Klin Med. 342 (1): 61–9. PMID 4298629.
  18. PENNA D, DE BRITO T, PUPO AA, MACHADO MM, AYROZA PA, DE ALMEIDA SS (1963). "KIDNEY BIOPSY IN HUMAN LEPTOSPIROSIS". Am J Trop Med Hyg. 12: 896–901. PMID 14072448.
  19. Sitprija, Visith; Evans, Hilary (1970). "The kidney in human leptospirosis". The American Journal of Medicine. 49 (6): 780–788. doi:10.1016/S0002-9343(70)80059-6. ISSN 0002-9343.
  20. De Biase L, De Curtis G, Paparoni S, Sciarra D, Campa PP (1987). "Fatal leptospiral myocarditis". G Ital Cardiol. 17 (11): 992–4. PMID 3446572.
  21. Brito, T. De; Morais, C. F.; Yasuda, P. H.; Lancellotti, Carmen P.; Hoshino-Shimizu, Sumie; Yamashiro, E.; Alves, V. A. Ferreira (2016). "Cardiovascular involvement in human and experimental leptospirosis: Pathologic findings and immunohistochemical detection of leptospiral antigen". Annals of Tropical Medicine & Parasitology. 81 (3): 207–214. doi:10.1080/00034983.1987.11812114. ISSN 0003-4983.
  22. AREAN VM (1957). "Leptospiral myocarditis". Lab Invest. 6 (5): 462–71. PMID 13464040.
  23. 23.0 23.1 Ramachandran S, Perera MV (1977). "Cardiac and pulmonary involvement in leptospirosis". Trans R Soc Trop Med Hyg. 71 (1): 56–9. PMID 871034.
  24. Nicodemo AC, Duarte MI, Alves VA, Takakura CF, Santos RT, Nicodemo EL (1997). "Lung lesions in human leptospirosis: microscopic, immunohistochemical, and ultrastructural features related to thrombocytopenia". Am J Trop Med Hyg. 56 (2): 181–7. PMID 9080878.
  25. Zaltzman M, Kallenbach JM, Goss GD, Lewis M, Zwi S, Gear JH (1981). "Adult respiratory distress syndrome in Leptospira canicola infection". Br Med J (Clin Res Ed). 283 (6290): 519–20. PMC 1507945. PMID 6790049.