1. What are the clinical manifestations that should alert a general practitioner to consider leptospirosis as the initial working diagnosis among patients presenting with fever?

   Any individual presenting with acute febrile illness of at least 2 days AND either residing in a flooded area or has high risk exposure (defined as wading in floods and contaminated water, contact of animal fluids, swimming in flood water or ingestion of contaminated water with or without cuts or wounds) AND presenting with at least two of the following symptoms: myalgia, calf tenderness, conjunctival suffusion, chills, abdominal pain, headache, jaundice, or oliguria should be considered a suspected leptospirosis case. The mean incubation period of leptospirosis is around 4 days (range 2-30 days)

2. Which patient will need hospital admission?

   Any suspected case of leptospirosis presenting with acute febrile illness and various manifestations BUT with stable vital signs, anicteric sclerae, with good urine output, and no evidence of meningismus / meningeal irritation, sepsis / septic shock, difficulty of breathing nor jaundice and can take oral medicine is considered MILD LEPTOSPIROSIS and can be managed on an OUT-PATIENT SETTING. Any suspected case of leptospirosis presenting with acute febrile illness associated with unstable vital signs, jaundice/icteric sclerae, abdominal pain, nausea, vomiting and diarrhea, oliguria/anuria, meningismus / meningeal irritation, sepsis / septic shock, altered mental states or difficulty of breathing and hemoptysis is considered MODERATE – SEVERE LEPTOSPIROSIS and BEST managed in a HEALTHCARE/HOSPITAL SETTING.

3. What antibiotics are recommended for patients suspected to have leptospirosis?

   For mild leptospirosis, doxycycline (hydrochloride, hyclate) is the drug of choice. Alternative drugs include amoxicillin and azithromycin dihydrate. For moderate-severe leptospirosis, penicillin G remains the drug of choice. Alternative drugs include parenteral ampicillin, 3rd generation cephalosporin (cefotaxime, ceftriaxone), and parenteral azithromycin dihydrate. Antibiotic therapy should be completed for 7 days, except for azithromycin dihydrate which could be given for 3 days.

Table 3. Dosage of Antibiotics Recommended for Leptospirosis

Table 4. Dosage of Antimicrobial Drugs in Adults with Renal Impairment

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