Since the 1990s, the prevalence of community-acquired MRSA (CA-MRSA) has begun to emerge worldwide as a cause of infection in community-based individuals without healthcare contact. In recent years, an increase in CA-MRSA in healthcare settings has been reported, and we also confirmed the predominance of presumed CA-MRSA strains in pediatric inpatients after the introduction of the PCR-based ORF typing (POT) method. However, its epidemiology remains unclear. To obtain an understanding of the molecular epidemiology of the MRSA clone, we then surveyed MRSA strains isolated from hospitalized children in 2003,2008 and 2013, and examined their molecular characteristics with SCCmec typing, multilocus sequence typing (MLST) and so on. The type of SCCmec has been shifting from type II, mainly the NewYork/Japan clone, to type IV since 2003, and the proportion of type IV in inpatient strains rose to 78.6% in 2013. Of the inpatient type IV 46 strains, ST8 snd CC8 accounted for 82.6%, and 93.5%, respectively, and at least 7 types of clones were estimated. PVL-producing strains were not observed, but tst was detected from 10 (21.7%) out of 46 type IV strains. All of the tst(＋) strains were ST8 and 9 of the strains were presumed to be potentially pathogenic ST8 CA-MRSA/J. With regard to the POT method, some sort of relationship was found between POT1 scores and SCCmec type II, type IV, CC5, and CC8, respectively. It is thought that analyzing the trend ofz clones will become more important in clinical practice and infection control. Although the POT method has certain limitations, it appears to be usuful as a molecular analysis method complementing others as routine examinations.
To provide correct information about dengue fever and Zika virus infection to Japanese overseas travelers, we analyzed the knowledge that people have regarding dengue fever and Zika virus infection. For this purpose, we asked Japanese people (n：500) who were planning to travel to a developing country in the next 6 months to complete a questionnaire on the internet.
From the results of the survey, we found that more than 80% of subjects had heard about dengue fever and Zika virus infection. Of these subjects, those who knew that the diseases were ʻtransmitted by mosquitosʼwere 82.8% for dengue fever, and 59.2% for Zika virus infection.
On the other hand, the fact that ʻThe mosquitos bite during the daytimeʼwas known by only 20% of subjects regarding dengue fever, and 14% regarding Zika virus infection, which were very low percentages.
In addition, subjects who knew that ʻZika virus can be sexually transmittedʼcomprised 13.2% of the total, and ʻZika virus may affect the fetusʼcomprised 23.8%. These were also very low percentages.
The information that mosquitos that mediate dengue fever and Zika virus infection bite during the daytime will be important for overseas travelers, to implement preventive measures. In the future, it is necessary to provide the correct information to Japanese travelers, including information on the sexual transmission of Zika virus and its effects on the fetus.
Achromobacter species are non-fermenting, Gram-negative bacilli. While Achromobacter xylosoxidans is known to be an opportunistic pathogen, little is known about infection due to A. xylosoxidans in pregnant women. We herein on report a case of bacteremia caused by A. xylosoxidans in a pregnant woman.
A 35-year-old pregnant Japanese woman was admitted due to urgent premature delivery. The patient developed urosepsis on day 36 following admission and was delivered by emergency caesarean section. Two sets of blood cultures were grown and were positive for A. xylosoxidans. The patient recovered immediately after treatment with a tazobactam/piperacillin regimen. However, the patient reported sudden severe right lower back pain on day 43 following admission. An enhanced abdominal CT showed active bleeding of a right renal angiomyolipoma (AML), for which we performed an arterial embolization. Based on antimicrobial susceptibilities, A. xylosoxidans bacteremia was treated with tazobactam/piperacillin for 14 days, during which the patientʼs clinical symptoms improved.
Our case suggests that A. xylosoxidans could be a causative pathogen of bacteremia in pregnant women and it is presumed that it is caused by urinary tract or catheter-related bloodstream infection.
A 48-year-old man was admitted to our hospital with osteomyelitis of his right thumb. His symptoms had started 1 month previously, 1 week after getting his right thumb caught in a door. MRI showed osteomyelitis of the distal phalanx of the right thumb. Debridement was performed and mycobacteria were isolated from the specimen one week after the culture was started. The mycobacterium was confirmed to be Mycobacterium goodii by 16S rRNA sequencing and an antibiotic susceptibility test. After debridement, treatment with clarithromycin, levofloxacin and amikacin was initiated empirically. According to the susceptibility test and adverse effect of antibiotics, we changed them to levofloxacin and trimethoprim-sulfamethoxazole. The antimicrobial treatment for 9 months resulted in successful resolution of the osteomyelitis.
To our knowledge, this is the first reported case of osteomyelitis caused by Mycobacterium goodii in Japan. Clinicians should consider this organism as a causative agent when treating patients with posttraumatic osteomyelitis.
Mycobacterium haemophilum has been described as a pathogen that causes cutaneous infections, septic arthritis, and pneumonitis in immunocompromised patients. It is being increasingly recognized in patients who have received treatment with anti-tumor necrosis factor-α (TNFα) agents, such as infliximab (IFX). We present a case of a 69-year-old female with a history of rheumatoid arthritis, who following treatment with prednisolone, methotrexate, and IFX for 7 years, developed disseminated M. haemophilum disease, which included cervical lymphadenitis, a lower leg subcutaneous tumor, and an upper eyelid conjunctive mass. Histological examination of biopsy specimens from the eyelid conjunctive mass, lymph node, and lower leg subcutaneous mass revealed granuloma with epithelioid cells and the presence of acid-fast bacilli (AFB) in the lymph node tissue. Molecular genetic analyses using the polymerase chain reaction method excluded Mycobacterium tuberculosis and Mycobacterium avium complex. Biopsy specimens cultured using BACTEC FX bottle (Becton Dickinson) and 2% Ogawa medium at 30℃ showed negative results. Subsequent testing of the frozen tissue specimens from the cervical LN and lower leg subcutaneous mass using mycobacterial DNA,hsp65, rpoB, 16S rRNA gene sequence analysis identified M. haemophilum. The patient was successfully treated with rifampicin, clarithromycin,and sitafloxacin. M.haemophilum infection should be considered in ulcerating skin lesions and/or arthritis, and pneumonia in patients treated with anti-TNFα agents, especially when microscopic observation reveals the presence of AFB and a routine mycobacterial culture remains negative.
Campylobacter fetus has rarely been reported as a pathogen of spontaneous bacterial peritonitis (SBP). A 60-year-old man with cirrhosis and diabetic nephropathy developed diarrhea, abdominal pain, and fever. Abdominal paracentesis revealed a significantly increased neutrophil count in the ascites. He was diagnosed as having SBP and treated empirically with ceftriaxone. Five days later, the blood culture performed on the day of admission yielded spiral-shaped gram negative bacilli. Both ascites and stool cultures were negative. Although conventional biochemical methods could not identify the colony, MALDI-TOF MS (Matrix Assisted Laser Desorption Ionization Time Of Flight Mass Spectrometry) identified it as C. fetus. Ceftriaxone was switched to ampicillin and continued for 21 days in total. He was fully recovered. Only 9 such patients have been reported including our patient, and 8 of them had a favorable outcome. SBP caused by C. fetus tends to present with diarrhea frequently and one patient died. Identification of C. fetus is important to select appropriate antimicrobial therapy. Our case suggests MALDI-TOF MS is a useful tool to identify C. fetus.
A 80-year-old man with non-tuberculous mycobacteriosis developed dyspnea and right chest pain and was therefore admitted to our hospital. <BR>Chest computed tomography demonstrated a right pleural effusion. Analysis of the aspirate from the pleural effusion revealed empyema and evidence of gram-positive coccal bacteria. Because his empyema did not resolve with chest tube drainage and antibiotics, video-assisted thoracoscopic surgery was performed,and Parvimonas micra was cultured from the pleural effusion. The sequence of the 16S rRNA gene was 99.4% identical to that of P. micra strain. Although the P. micra infection in the pleural cavity is uncommon, it should be considered as a pathogenic bacterium of empyema.