Leptospirosis An Emerging Infectious Disease

1. LeptospirosisAn Emerging Infectious Disease Dr.S.P.K.Wathudura Consultant Physician

2. Synonyms

3. Over View • Most common, underdiagnosed zoonosis • Srilanka all over and India - cases are reported from Kerala, Tamil Nadu, AP, Karnataka, Maharashtra, Gujarat & Andamans. • Source - Animals (rodents and domestic animals) Epidemiological factors • Contaminated environment, Rainfall • High risk groups, endemic in Srilanka and in all states of India • First description by Weil in 1886

4. Over View continued • Rural > Urban • Male > Female (10 : 1) • Clinical Features –mild to severe life threatening • Mimics many common febrile illnesses • Diagnosis - difficult to confirm • Treatment – effective, if started early (<5 days)

5. The Causative Bacterium

6. Leptospira under the Microscope Dark Field Microscopy FL Long, Thin, Highly Coiled

7. Epidemiology • Rainfall; Contaminated environment • Poor Sanitation; Inadequate drainage facilities • Presence of rodents, cattle & stray dogs • Walking/ working bare foot poses high risk • Difficult to pinpoint the source of infection • Any person can get infected, if exposed to contaminated environment

8. Risk Groups Occupational exposure • Farmers – Rice, Sugarcane, Vegetables, Cattle, Pigs • Sewerage workers; Abattoirs, Butchers • Veterinarians, Lab staff, Miners, Soldiers • Fishermen – Inland (not on the sea) Recreational activities • Swimming, Sailing, Marathon runners, Gardening

9. Reservoirs of Infection • Rodents • (Rattus rattus, Rattus norvegicus, Mus musculus) • Dogs • Wild animals • Domesticated animals • Caged game animals • Leptospira are excreted in the urine

10. Modes of Transmission 1.Direct contact with urine or tissue of infected animal Through skin abrasions, intact mucus membrane 2. Indirect contact Broken skin with infected soil, water or vegetation Ingestion of contaminated food & water 3. Droplet infection Inhalation of droplets of infected urine

11. Transmission Human infection is accidental No human to human transmission

12. Leptospirosis

13. Natural History

14. Pathogenesis of Severe Disease Vasculitis Damage to small blood vessels Leptospira Massive migration of fluid from Intravascular to interstitial compartment Direct cytotoxic injury Immunological injury Renal dysfunction, vascular Injury to internal organs

15. ClinicalIllnesses

16. Clinical Presentation

17. Clinical Progression of Icteric (Weil’s Disease) and Anicteric Leptospirosis

18. Anicteric Presentation Subsequent Initial

19. Icteric Leptospirosis

20. Icteric Leptospirosis KIDNEYS – Mild to Severe Urinalysis : Hematuria / Pyuria / Proteinuria Renal Failure: Pre renal azotemia, ATN / AIN Oliguric / Non Oliguric Mechanism Nephrotoxicity – Endotoxin, (Direct ) Bacterial migration, Toxic Metabolites Hypoperfusion – Hypotension, Fluid loss/ Fluid shift G.I. Bleed, Myocarditis

21. Hemorrhagic Manifestations Hemorrhagic Fever - Vascular injury • Respiratory, Alimentary, Renal & Genital tracts • More common in Icteric & with Renal Failure • Reported in Srilanka, Korea, Andaman’s & Brazil Hemorrhagic Pneumonitis • Hemoptysis / Respiratory failure • CXR : Single/ Multiple ill defined opacities • Occurs in 2nd week (as early as 24-48 hours) • Reported in Srilanka, Korea, Andaman’s & Nicaragua

23. SubconjunctivalHaemorrhage Icterus

24. Atypical Pneumonia

25. Cardiac Form Cardiac manifestations • Hemorrhagic Myocarditis • Cardiomyopathy / Cardiac failure • Arrhythmias, Hypotension / Death • Atrial fibrillation / Conduction defects ECG changes • Non Specific ST-T changes • Low voltage complexes Reported in Srilanka, Barbados & Portugal

26. Other Manifestations Aseptic Meningo-encephalitis • It is rare; It occurs in the Immune phase • CSF –­ proteins , ­lymphocytes  • Convulsions, Encephalitis, Myelitis & Polyneuropathy Ocular manifestations • Late complication; Conjunctival suffusion/hemorrhage • Anterior uveitis, Iritis, Iridocyclitis, chorioretinitis • Occurs in 2 weeks to 1 yr. (average 6 months)

33. Differential Diagnosis

34. Laboratory Tests • TC / DC / ESR / Hb / Platelet count • Serum Bilirubin / SGOT/ SGPT • Blood Urea, Creatinine & Electrolytes • Chest X-Ray; ECG • Tests for diagnosis of Leptospirosis • Culture for Leptospira: Positive • MAT; Sero conversion or 4 fold rise/ high titer • ELISA / MSAT : positive • MAT: Microscopic agglutination test • (M)SAT: Microscopic slide agglutination Test

35. Problems in Diagnosis

36. Interpretation of Tests

37. Interpretation of Tests

38. Time Relationship of Tests MAT ELISA or SAT

39. WHO Guide - Faine’s Criteria Score of 25 or more – Presumptive Diagnosis Score of 20 to 25 – Possible case of leptospirosis

40. Approach to Diagnosis

41. Treatment Oral Treatment 7 to 10 day IV Treatment 5 to 7 days Jarisch Herxheimer Reaction

42. Special Measures

43. Significance of Steroids in Weil’s disease • EARLY use of IV Methyl Prednisolone in Weil’s disease increases survival • No survival benefit if its started after developing complications (Haemorrhagic pneumonitis, ARF,myocarditis or acute liver failure)

44. Scoring system to decide on starting steroids

45. Total score of 2 or more indicates the need of IV methyl prednisolone as pulse therapy IV 500mg-1000mg daily for 3 days Followed by oral 8mg bd for 5 days

46. Supportive Care • Bed rest • Input- output • IV line- IV fluids • IV noradrenaline and +/- inotropes • Paracetamol – SOS • Oxygen –SOS

47. Haemodialysis in early phase of ARF shortens the ICU stay and improves haemodynamical stability

48. Monitoring • Lookout for complications • Urine output • Pulse, BP, hydration, cyanosis, distress, bleeding, pallor, LOC, lung bases • Urea, Creatinine, potassium • ECG (myocarditis, high K+ )

49. Prognosis and Mortality

50. Ctd • In the history • In India pulmonary leptospirosis treated with iv bolus mp with a good response • In France in 1994 similar cases treated with 1 gram iv bolus daily for 3 days • In the management of sepsis and acute lung injury place of steroids accepted now • Prof.S.A.M.Kularathna et al.in 2008 started a descriptive study