[Clinical features and outcome of infection of type 2 Streptococcus suis in human]

To analysis the clinical features and efficacy of treatment for patients with type 2 Streptococcus suis (S. suis 2) infection, and to inform better diagnosis and treatment of S. suis 2.

Clinical data of 68 patients with S. suis 2 infection were retrieved retrospectively. The diagnoses were confirmed by clinical symtom or/and isolation of S. suis 2 from the infected sites in Shichuan province in the summer of 2005. The patients ranged from general type (simple sepsis) to septic shock type; meningitis type and mixed type.

The outbreak of S. suis 2 infection occurred in June to August in 2005. The common source of infection came from pigs. The people in great risks were farmers who exposed to sick or dead pigs with S. suis 2 infection. Most infection occurred on the people who slaughtered infected pigs, followed by those who dressed infected meats. The prominent symptoms included fever with sharp chills, dizziness, headache, malaise and myalgia. Some patients had abdominal pain and diarrhea. Septic shock and coma often occurred in severe cases. According to the clinical manifestations, patients were categorized into four different clinical types: general type, septic shock type, meningitis type, and mixed type. S. suis 2 isolated from the patients were susceptible to most antimicrobial agents, except for tetracycline. All of the patients were treated with beta-lactam antibiotics (penicillins or cephalosporins). Some were given combined antimicrobial agents. Seventy seven percent (52/68) of patients survived. All of the general patients recovered completely. Fifty eight percent (15/26) of patients with septic shock died. The artificial ventilation and persistent blood filtering treatment played an important role for treating patients with septic shock. Although most patients with meningitis (97.5%) survived, a decrease in hearing or even hearing loss occurred to some of the survivors.

Purulent meningitis and septic shock are the major clinical manifestations for S. suis 2 infection in human. The treatment for patients with meningitis is more effective than that for patients with septic shock.