Management of Central Nervous System Infections, Vientiane, Laos, 2003-2011

Abstract

During 2003-2011, we recruited 1,065 patients of all ages admitted to Mahosot Hospital (Vientiane, Laos) with suspected central nervous system (CNS) infection. Etiologies were laboratory confirmed for 42.3% of patients, who mostly had infections with emerging pathogens: viruses in 16.2% (mainly Japanese encephalitis virus [8.8%]); bacteria in 16.4% (including Orientia tsutsugamushi [2.9%], Leptospira spp. [2.3%], and Rickettsia spp. [2.3%]); and Cryptococcus spp. fungi in 6.6%. We observed no significant differences in distribution of clinical encephalitis and meningitis by bacterial or viral etiology. However, patients with bacterial CNS infection were more likely to have a history of diabetes than others. Death (26.3%) was associated with low Glasgow Coma Scale score, and the mortality rate was higher for patients with bacterial than viral infections. No clinical or laboratory variables could guide antibiotic selection. We conclude that high-dependency units and first-line treatment with ceftriaxone and doxycycline for suspected CNS infections could improve patient survival in Laos.

Keywords: Asia; Cryptococcus; Japanese encephalitis virus; Lao; Laos; Leptospira; Orientia tsutsugamushi; Rickettsia; WHO encephalitis; WHO meningitis; antibiotics; antimicrobial medicines; bacteria; bacterial infections; central nervous system infections; diabetes; encephalitis; meningitis; meningitis/encephalitis; mortality; patient care management; viral infections; viruses.

Figure 1

WHO encephalitis and meningitis case definitions. *Definitions from WHO (18). †Defined here as Glasgow Coma Scale score <15. ‡Not “with sudden onset of fever >38.5°C” as recommended by the WHO because we saw patients, especially young children, with meningitis but with temperatures below the WHO temperature criterion. §Patients with history of fever or documented fever (>37.5°C). ¶History of neck stiffness or neck stiffness on examination. WHO, World Health Organization.

Figure 2

Distribution of clinical manifestations among patients with suspected CNS infection, by age group and etiology, Laos, January 2003–August 2011. A) WHO criteria; B) additional criteria (Table 1). Children were patients <15 years of age and adults patients >15 years of age. Numbers above bars indicate number of patients in group. CNS, central nervous system; GCS, Glasgow Coma Scale; WHO, World Health Organization.

Figure 3

Recruited patients with suspected central nervous system infection, by month, Laos, January 2003–August 2011. A) Total patients recruited by month cumulating all studied years. B) Patients recruited each month of each year. Light and dark shades of colors were used in an alternating pattern to facilitate graph reading.

Figure 4

Distribution of clinical presentations in patients with suspected central nervous system infection, by confirmed etiology, Laos, January 2003–August 2011. Analysis per pathogen includes only patients with monoinfections. Other bacteria include 7 Escherichia coli, 4 Streptococcus agalactiae, 4 Neisseria meningitidis, 1 Salmonella enterica group D, 1 S. enterica group B or C, 5 S. enterica serovar typhi, 4 Streptococcus suis, 3 Klebsiella pneumoniae, 7 Haemophilus influenzae type b, 5 Burkholderia pseudomallei, 6 Staphylococcus aureus, and 1 Morganella morganii. Blue font indicates viruses, red font indicates bacteria, and black font indicates fungi. CNS, central nervous system; GCS, Glasgow Coma Scale; WHO, World Health Organization.