Laboratory findings in icteric leptospirosis are as above except that renal function markers show greater pathology. The index of suspicion is increased by occupational or other exposure to contaminated water or other potential exposure to infected urine. As previously noted, leptospires are present in the blood for about one week after onset of the illness, and then are present in urine. Seroconversion or increased antibody titer in the microscopic agglutination test may thus occur after about one week. For anicteric leptospirosis, principal differentials are aseptic meningitis related to other entities, fever of unknown origin, influenza, appendicitis, and gastroenteritis.
Leptospirosis responds well to treatment, especially if started early in the illness.
OR amoxicillin 500 mg po qid. Jarisch-Herxheimer reactions to therapy may occur, i.e., acute febrile reaction, accompanied by headache and myalgia due to release of toxic products of killed spirochetes. The reaction usually occurs within 24 hours of initiation of therapy and subsides about 24 hours later. Therapy is continued unless symptoms are severe. Renal failure is treated as in other circumstances.