• Also known as septicemic phase.
• Begins abruptly.
• Characterized by nonspecific signs such as fever, chills, headache and conjunctival suffusion.
• Associate with severe myalgia.
• Other less common findings include: Photophobia, lymphadenopathy, abdominal pain, nausea, vomiting, a transient rash, sore throat, coughing or chest pain.
• Characterestic of this phase also includes: symptoms lasts several days to a week, which is followed by a brief remission, during which the temperature drops and the symptoms disappear.

• It is also known as leptospiruric phase.
• Circulating (IgM) antibodies are produced and leptospires are present in the urine
• Characterestic findings that differentiate from other febrile illnesses are myalgia and conjunctival suffusion.^[4]
• Myalgia often involves in calf muscles and less commonly involves abdominal and paraspinal muscles.

• More common but serious illness is uncommon.
• Most of cases present either sub-clinical or very mild severity.
• Few cases present with a febrile illness of sudden onset.
• Other symptoms include chills, headache (severe with retro-orbital pain and photophobia), myalgia, abdominal pain, conjunctival suffusion, and skin rash (transient and last <24 hours).
• May progress to aseptic meningitis in ≤25% of patients and more common in younger age group than the patients with icteric leptospirosis.
• Mortality is very less when compared to icteric leptospirosis.

• Rapidly progressive and severe form of leptospirosis
• Less common form of leptospirosis with incidence of 5%-10%.
• Jaundice is not associate with hepatocellular injury, eventually LFT returns to normal after recovery.
• High mortality rate with a range of 5%-15%.

involvement is known as Weil’s disease.

• Hepatic: Mild to severe form of jaundice developed within 4-7 days after the initial clinical presentation that can progress to hepatic failure or hepatic encephalopathy.
• Renal: Very common presentation involving kidneys is acute interstitial nephritis, with cola colored urine, oliguria or anuria.
• Pulmonary: Milder form of leptospirosis presents with cough, chest pain and blood tinged sputum, where as in severe form present with cough, hemoptysis, rapidly increasing breathlessness which may lead to respiratory failure and death. Hemorrhagic pneumonitis with interstitial and intra alveolar hemorrhage is the commonest cause of death in leptospirosis with case fatality rate of 0%-15%.
• Cardiovascualar: Arrhythmias present with syncope and palpitations.
• Nervous system: Meningitis, encephalitis, focal defecits, spasticity, paralysis, peripheral neuropathies, nerve palsies and radiculopathies.