Leptospirosis 

-         caused by genus – leptospires

-         Widely reported from all countries except Antartica

-         L. Icterohaemorrhagica – cause of water disease

Organism

-flexible, helical, mobile organism.

Demonstration  - by silver staining (or) flourescent dyes

-         by dark field, phase contrast or microscopy

Obligate anerobes-         Opt temp 28 degree c to 38 degree c

-         Gen time 7 – 16 hrs

Growth occurs in 6 – 14 days

Susceptibility – denication drying and sunlight kills

-         cannot survive in anaerobic conditions

-         Soil moisture, water holding capacity of soil, rainfall are

Gastric ph sterile H₂O at neutral PH

Killed at acidic PH uncontaminated river water

-Sewage , sea water

Conc. soda 2% formula 2% Chlorine 1 % kills in 3 hrs

Sensitive AB  penicillin

                        Streptomycin

                        Tetracyclin

Prevention Doxy 200 mg once a week

Leptospire organisms : confined to kidneys and excreted in urine.

Carriers   Cats, dogs, sheep, Rats,, cattle, horses and pigs.

Entry of organism  Through abraded skin and water sodden skin

Men temporary urinary carrier, upto 4 wks.

Man is man transmission is unusual

 Toxins like bilirubin, endotoxin,cytotoxic factors (plasma and tissues) induce extensive vascular  lesions even when the organismn are absent.

Man – dead end host of this disease.

Pathogenesis

                Abraded skin, mucous membrane ( Leptospiraemic phase)

Immune phase (Symptomatic phase)

1)      eyes à chronic / recurrent uveites

2)      kidney à immune complex GN

3)      Brain à aseptic meningitis

4)      Liver à Liver food, hepatic failure

Acute phase hrs to 7 days.

Immune phase 4 days to 30 days.

Diagnosis     anicteric

Leucocytosis – 70,000 / cc

Neutrophil -  > 70 %

Anaemia – unusual

Icteric

            Leucopenia

Anaemia due to azotemia / ges / increased  bihrubin

Cpk increased to 5 times

GRT increased

Urine proteinuria in bile pigments.

RAC  / granular & hyaline costs

Rx made on basis of clinical manifestation, blood count, blood urea, urine exam and serology

Microscopy dark field microscopy

Culture samples used

CSF

Blood

Urine

Tissue fluid

Blood should be heparinised for transport purpose

Urine add carbonate so met alkalanity to preserved and chances of survival is better.

IgA antibodies indicate recent information

Appear early in  (5^th  - 6^th  day)

IgG antibodies appear late and tend to persisit for a long time

MATC microscopic aggln IgG EUSA positive will show evidence of previous information.  Urine organismn excreted during 2^nd week

Control of prevention found during Ist week.