Chapter 25
Laboratory Diagnosis of Leptospirosis
Nobuo Koizumi
Abstract
The diagnosis of leptospirosis depends on specific laboratory tests because nonspecific and diverse clinical
manifestations make clinical diagnosis difficult and it is easily confused with other infectious diseases in the
tropics. Suitable laboratory diagnostic tests vary depending on the stage of the disease, requiring the
combination of diagnostic tests using appropriate specimens at each disease stage.
Key words Culture, Diagnosis, Microscopic agglutination test (MAT), Nucleic acid amplification test
(NAAT), Serology
1 Introduction
Leptospirosis is an emerging zoonotic disease that is widespread
globally. A World Health Organization (WHO) experts group
estimated one million cases and 58,900 deaths due to leptospirosis
worldwide each year, of which more than 70% occur in the tropical,
poorest regions of the world [1]. Leptospirosis has been recognized
as a major cause of acute undifferentiated fever in various parts of
the world [2–6]. Nonspecific and diverse clinical manifestations
make clinical diagnosis difficult, and it is easily confused with
many other diseases in the tropics, such as dengue fever, malaria,
and scrub typhus [7]. In addition, general clinical laboratory test
findings are nonspecific. Therefore, the diagnosis of leptospirosis
depends on specific laboratory tests. Table 1 describes the case
definitions of leptospirosis, as recommended by a group of WHO
experts [8].
Suitable laboratory diagnostic tests vary depending on the
stage of the disease. During the acute phase, less than 7 days after
onset, leptospires exist in the bloodstream (leptospiremia). Detection of Leptospira spp. in the blood by culturing and/or nucleic
acid amplification tests (NAATs) is superior to antibody detection,
but the timing of blood collection and the administration of antibiotics can affect their sensitivity and result in a false-negative result.
Nobuo Koizumi and Mathieu Picardeau (eds.), Leptospira spp.: Methods and Protocols, Methods in Molecular Biology, vol. 2134,
https://doi.org/10.1007/978-1-0716-0459-5_25, © Springer Science+Business Media, LLC, part of Springer Nature 2020
277
Laboratory Diagnosis of Leptospirosis
Nobuo Koizumi
Abstract
The diagnosis of leptospirosis depends on specific laboratory tests because nonspecific and diverse clinical
manifestations make clinical diagnosis difficult and it is easily confused with other infectious diseases in the
tropics. Suitable laboratory diagnostic tests vary depending on the stage of the disease, requiring the
combination of diagnostic tests using appropriate specimens at each disease stage.
Key words Culture, Diagnosis, Microscopic agglutination test (MAT), Nucleic acid amplification test
(NAAT), Serology
1 Introduction
Leptospirosis is an emerging zoonotic disease that is widespread
globally. A World Health Organization (WHO) experts group
estimated one million cases and 58,900 deaths due to leptospirosis
worldwide each year, of which more than 70% occur in the tropical,
poorest regions of the world [1]. Leptospirosis has been recognized
as a major cause of acute undifferentiated fever in various parts of
the world [2–6]. Nonspecific and diverse clinical manifestations
make clinical diagnosis difficult, and it is easily confused with
many other diseases in the tropics, such as dengue fever, malaria,
and scrub typhus [7]. In addition, general clinical laboratory test
findings are nonspecific. Therefore, the diagnosis of leptospirosis
depends on specific laboratory tests. Table 1 describes the case
definitions of leptospirosis, as recommended by a group of WHO
experts [8].
Suitable laboratory diagnostic tests vary depending on the
stage of the disease. During the acute phase, less than 7 days after
onset, leptospires exist in the bloodstream (leptospiremia). Detection of Leptospira spp. in the blood by culturing and/or nucleic
acid amplification tests (NAATs) is superior to antibody detection,
but the timing of blood collection and the administration of antibiotics can affect their sensitivity and result in a false-negative result.
Nobuo Koizumi and Mathieu Picardeau (eds.), Leptospira spp.: Methods and Protocols, Methods in Molecular Biology, vol. 2134,
https://doi.org/10.1007/978-1-0716-0459-5_25, © Springer Science+Business Media, LLC, part of Springer Nature 2020
277