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The recent increase in macrolide-resistant Mycoplasma pneumoniae (M. pneumoniae) in Asia has become a continuing problem. A point-of-care testing method that can quickly detect M. pneumoniae and macrolide-resistant mutations (MR mutations) is critical to proper antimicrobial use. Smart Gene TM (MIZUHO MEDY Co., Ltd. Tosu-City, Saga, Japan) is a compact and inexpensive fully automatic gene analyzer that combines amplification with polymerase chain reaction (PCR) and the quenching probe method to specify the gene and MR mutations simultaneously. We performed a clinical evaluation of this device and its reagents on pediatric patients with M. pneumoniae -suspected respiratory infections and evaluated the impact of the assay on antimicrobial selection. Using real-time PCR as a comparison control, the sensitivity of Smart Gene TM was 97.8% (44/45), its specificity was 93.3% (98/105) and its overall concordance rate was 94.7% (142/150). The overall concordance rate of Smart Gene TM diagnosis of MR mutations in comparison with sequence analysis was 100% (48/48). The ratio of MR mutations was significantly higher at high-level medical institutions than at a primary medical clinic (P = 0.023), and changes in antibiotic therapy to drugs other than macrolides was significantly more common in patients with MR mutations (P = 0.00024). Smart Gene TM demonstrated excellent utility in the diagnosis of M. pneumoniae and the selection of appropriate antimicrobials for MR mutations at primary medical institutions, which play a central role in community-acquired pneumonia care. The use of this device may reduce referrals to high-level medical institutions for respiratory infections, thereby reducing the medical and economic burden on patients.

Benign convulsions associated with mild gastroenteritis (CwG) are a commonly observed disorder in Asia, especially in infants and seniors. Here, we describe a retrospective study about the clinical features of CwG in 62 children hospitalized at St. Mary's Hospital (Kurume City, Japan) between January 1, 2000 and March 31, 2006, and further evaluate the efficacies of various anticonvulsant treatments for patients with CwG due to either rotavirus or norovirus. Causative diarrheal viruses were detected in 71% of the fecal specimens tested; 30 patients were positive for rotavirus, nine patients were positive for norovirus, two patients were positive for sapovirus, two patients were positive for adenovirus, and one patient was positive for coxackievirus A4. The age of onset for patients with norovirus-positive CwG (16.7+/-2.7 months) was significantly lower than that of patients with rotavirus-positive CwG (23.0+/-8.7 months). The duration of the seizures due to norovirus infection (11.8+/-12.0 h) was significantly longer than that due to rotavirus infection (4.9+/-5.7 h). There were no significant differences between the two groups with regard to the results of blood chemistry analysis, including the concentrations of serum electrolytes, blood glucose levels, and liver function tests. In this preliminary study, the duration of seizures in patients with CwG due to norovirus that was treated with carbamazepine was significantly shorter than the duration of seizures in the patients treated with another anticonvulsant (phenobarbital). Further randomized controlled studies are required to clarify the efficacies of the various anticonvulsants for patients with CwG.

In Japan, the routine immunization program with oral polio vaccine (OPV) has been suspended since September 2012, when a program with 4 doses of inactivated monovalent polio vaccine (IPV) or quadrivalent vaccine against diphtheria, pertussis, and tetanus with IPV (DTaP-IPV) was introduced. The aim of this study was to examine the interchangeability among these 3 types of polio vaccines.We conducted a prospective cohort study at 5 pediatric clinics in Japan. A total of 153 infants were assigned to 1 of the 4 groups by considering the vaccination history of OPV and trivalent vaccine against DTaP. Eleven infants with a history of OPV received 3 doses of DTaP-IPV; 49 infants with a history of OPV and DTaP received 3 doses of IPV; 50 polio vaccine-naive infants received 2 doses of IPV followed by 2 doses of DTaP-IPV; and 43 polio vaccine-naive infants received 2 doses of DTaP-IPV followed by IPV. The immunogenicity after polio vaccination was evaluated among these 4 groups.After 2 doses of polio vaccination, more than 80% of the infants exhibited a neutralization antibody titer ≥1:8 for all Sabin strains and wild strains in all groups. After the third dose, the seroprotection proportion (i.e., a neutralization antibody titer ≥1:8) reached about 100%. After the fourth dose, a neutralization antibody titer exceeded the required protective levels (i.e., a neutralization antibody titer ≥1:8) considerably in all groups.Four doses of polio vaccines induced a sufficient level of immunity in Japanese infants, irrespective of vaccine combinations or order.

Isolated 3-methylcrotonyl-CoA carboxylase (MCC) deficiency appears to be the most frequent organic aciduria detected in tandem mass spectrometry (MS/MS) screening programs in the United States, Australia, and Europe. A pilot study of newborn screening using MS/MS has recently been commenced in Japan. Our group detected two asymptomatic MCC deficiency patients by the pilot screening and collected data on another three MCC deficiency patients to study the molecular bases of the MCC deficiency in Japan. Molecular analyses revealed novel mutations in one of the causative genes, MCCA or MCCB, in all five of the patients: nonsense and frameshift mutations in MCCA (c.1750C > T/c.901_902delAA) in patient 1, nonsense and frameshift mutations in MCCB (c.1054_1055delGG/c.592C > T) in patient 2, frameshift and missense mutations in MCCB (c.1625_1626insGG/c.653_654CA > TT) in patient 3, a homozygous missense mutation in MCCA (c.1380T > G/ 1380T > G) in patient 4, and compound heterozygous missense mutations in MCCB (c.569A > G/ c.838G > T) in patient 5. No obvious clinical symptoms were observed in patients 1, 2, and 3. Patient 4 had severe neurological impairment and patient 5 developed Reye-like syndrome. The increasing use of MS/MS newborn screening in Japan will further clarify the clinical and genetic heterogeneity among patients with MCC deficiency in the Japanese population.