Cerebrospinal fluid analysis of meningitis due to scrub typhus
All patients admitted to a tertiary hospital in South India with ST and had clinical features of meningitis were included in this retrospective observational study from 2007-2012. ST was confirmed by the presence of a pathognomonic eschar and/or ST IgM Enzyme Linked Immunosorbent Assay (InBios International, Seattle, USA) positivity. Other common CNS infections were ruled out by appropriate tests. This study documents the details of CSF analysis among patients with meningitis due to ST.
The study cohort contained 190 patients with meningitis due to ST. The mean age of the patients was 41 ± 4 years, and there was a slight male predominance (56.8%). The mean duration of fever prior to presentation was 9.4 ± 3 days. Common presenting complaints were headache (64.2%), nausea/vomiting (60%), altered sensorium (53.7%), and seizures (22.1%). An eschar was seen in 27.3% (52/190) of patients. The mean CSF WBC count was 80 cells/cu mm (range: 5-740 cells/cu mm). There was clear lymphocyte predominance (mean-87.6%). The mean CSF protein level was 105 mg% (range: 13-640 mg %). The mean CSF sugar level was 63.9 mg% (range: 25-350 mg %) and the CSF sugar level was less than 45 mg% in 18.2% of cases. Hepatic involvement was seen in 59.6% of patients, pulmonary involvement in 19.7%, renal dysfunction in 18.6% and cardiovascular involvement in 15% of the patients. The mortality rate was 6.3% (12/190). Univariate analysis showed the presence of an eschar (15.4% vs 2.2%; p=0.002; OR: 8.1) and altered sensorium (9.8% vs 1.1%; p=0.012; OR: 9.2) to be significant predictors of mortality.
In endemic areas Scrub typhus should be considered one of the differentials of aseptic meningitis.CSF analysis in ST may show very high WBC count with lymphocyte predominance, elevated protein level or low sugar level and should be differentiated from other CNS infections.
S. Patole, None
K. Gunasekaran, None
G. Varghese, None