Abstract:

The Streptococcus suis meningitis patients often accompany with visual and hearing impairment， and their life quality is affected seriously after recovery. Our department admitted a 59-year-old male patient. The patient presented headache accompanied by fever， followed by decreased vision acuity in both eyes and reduced hearing in the right ear. The patient was alerted and oriented， with only light sensation in both eyes and reduced hearing in both ears （more pronounced on the right side）. The neck strength was 3 horizontal fingers， and Kernig sign was positive. Magnetic resonance imaging （MRI） head scan showed patchy abnormal signals in the white matter of the right frontal lobe， while further enhanced MRI scan did not reveal any abnormal signals. The cerebrospinal fluid appeared slightly yellow and turbid color with blood droplets at the initial drip， and the total number of leukocytes and protein level were significantly increased.The glucose and chloride levels were decreased with the multinucleated cells accounting for 79% of the cellular components. The cerebrospinal fluid IgG level was 82.25 mg·L^-1. Blood culture yielded Streptococcus suis as the causative pathogen. Metagenomic next generation sequencing （mNGS） in cerebrospinal fluid indicated Gram-positive bacteria， with 7 001 Streptococcus suis sequences detected. The patient was diagnosed with Streptococcus suis meningitis and treated with anti-infective therapy complemented by hormone and symptomatic treatment. Follow-up interviews at 6 and 18 months post-discharge revealed a satisfactory recovery of visual acuity， while the hearing did not improve significantly compared to at the time of discharge. In the patients with a history of exposure with sick or dead pigs who develop signs of meningitis accompanied by simultaneous involvement of other organs such as eyes and ears， Streptococcus suis meningitis should be considered and empirical anti-infective treatment should be provided as soon as possible. Blood culture and mNGS for definitive diagnosis should be conducted promptly. Combined application of Streptococcus suis-sensitive antibiotics and dexamethasone may help improve hearing impairments in these patients.

Key words: Streptococcus suis, Meningitis, Hearing impairment, Visual impairment, Cerebrospinal fluid, Metagenomic next generation sequencing