Discussion
We reported a rare case of pyogenic ventriculitis associated withS. suis infection. People who handle pork or its derivative products are at a high risk of S. suis infection [1] since the route of entry of the organism into humans is via small skin wounds [12]. However, recent studies have shown that only 20% of patients reported having skin wounds when handling pork [13]. Kushiyaki is a traditional Japanese dish in which bite-sized pieces of chicken or pork are skewered and grilled over an open fire. In this case, the patient was a kushiyaki chef who handled pork with his bare hands. Since there were small scars on his hands, probably linked to cooking kushiyaki, we considered that to be the route of his infection. Kushiyaki chefs may be at a higher risk of infection than people engaging in other activities involving pigs. As there is no S. suis vaccine for humans [14], hand washing and wearing personal protection equipment are the most practical preventive measures.
Several patients with S. suis meningitis successfully recovered following a treatment scheme similar to that used for pneumococcal meningitis [15]. However, other patients with S. suismeningitis showed relapse 2 weeks post-treatment completion and required prolonged therapy (4–6 weeks) [16]. Dejace et al. suggested that treatment should be tailored to clinical and laboratory findings [17]. A recent review found that the antimicrobial treatment duration ranged from 7 to 42 days in cases of meningitis, spondylitis, and endocarditis [1]. In this case, S. suis infection only led to meningitis and pyogenic ventriculitis. Ventriculitis is a rare condition secondary to meningitis [18] that can cause persistent infection and treatment failure [19, 20]. Additionally, if meningitis is associated with ventriculitis, prolonged antibiotic treatment might be required. Only one case of S. suismeningitis associated with ventriculitis has been reported so far; the patient required longer antibiotic treatment than the usual 24-day course for bacterial meningitis [21]. However, few studies have reported ventriculitis in cases involving long-term antimicrobial treatment forS. suis meningitis, suggesting that ventriculitis might be an underlying cause for disease recurrence. Furthermore, although our patient was treated for a longer period because of the presence of ventriculitis, the recommended treatment duration for S. suis -associated ventriculitis has not been determined [22]; thus, further studies are needed. As ventriculitis is most frequently detected based on diffusion-weighted MRI findings [23], MRI should be performed in cases of suspected ventriculitis, especially in cases ofS. suis meningitis involving a poor response to treatment.