[Rate and clinical characteristics of mumps reinfection].

Mumps infection is anecdotally believed to occur only once over a lifetime. However, in recent years, it has gradually come to be recognized among pediatricians that mumps reinfection is not a rare condition, and some criteria for the mumps reinfection have been proposed. One of the widely accepted criteria is levels higher than 25.8 IU/dl of serum IgG antibodies against the mumps virus and lower than 2.0 IU/dl of serum IgM antibodies. From July 2010 to June 2011, 45 patients with acute swelling of the major salivary gland(s) were enrolled into our survey of mumps reinfection in Tsuchiura Kyodo General hospital. Serum IgG and IgM antibodies against the mumps virus were measured at the initial visit. Ten cases were diagnosed as having primary infection with the mumps virus, while the other 10 cases were diagnosed as having reinfection with the mumps virus according to the criteria. The present study suggests that mumps reinfection is a common condition in patients with acute swelling of the major salivary glands in adulthood.

[Three cases of suspected re-infection of mumps virus].

A 32-year-old woman, 5-year-old girl, and 33-year-old man visited our otorhinolaryngology outpatient clinic with tumentia of the unilateral parotid gland. A high titer of serum IgG antibodies against the mumps virus was detected. Around the same time, other members of their families had the same parotid tumentia, and they were diagnosed as having their first mumps infection. Therefore, the diagnosis of the three cases was strongly suspected to be re-infection with mumps. In Japan, it was classically believed that the mumps virus infection occurs only once in patients and reinfection doesn't occur. However, some pediatricians in Japan have reported that re-infection with mumps is strongly suspected when high titers of serum IgG antibodies against the mumps virus are found at the initial visit. It is now believed many more examples of mumps re-infection cases have existed than we previously believed. When high titers of serum IgG antibodies against the mumps virus are detected at an initial visit in patients who have had mumps previously, re-infection should be strongly suspected. And to make it certain, we suggest that the mumps IgG antibodies should be checked twice to confirm the diagnosis. If elevation of the IgG antibodies persist, the diagnosis will be much more certain.

[Case of acute pharyngitis caused by Corynebacterium ulcerans in Ibaraki Prefecture].

We report on the case of a 51-year-old woman who presented with refractory pharyngitis caused by toxigenic Corynebacteriumn ulcerans (C. ulcerans). Thick pseudomembrane formations and yellowish pus were observed in her nasopharynx. Based on her clinical course and history of breeding cats, we considered C. ulcerans infection as the possible diagnosis. She was treated with macrolide administration and her symptoms immediately improved. C. ulcerans was identified in pus from the patient's pharynx as well as in discharge material from her cat's eyes, and C. ulcerans was thought to have caused her pharyngitis. C. ulcerans is one of the infecting bacteria which can cause a zoonotic infection. In Japan, some cases with C. ulcerans infection from cats have been reported. It is important that we should consider C. ulcerans infection as a differential diagnosis of refractory pharyngitis.