Takao Kobayashi

Methicillin resistant Staphylococcus aureus in a Japanese community hospital: 5-year experience.

Methicillin resistant Staphylococcus aureus (MRSA) is exceptionally critical to infection treatment and control in the health-care setting. MRSA has been detected at high levels in Japan, and the frequency of MRSA infection must be ascertained to provide a baseline with which to assess various infection control efforts. We studied MRSA infection rate at a general hospital in Japan in all 65,135 inpatients of Sendai Kousei Hospital from January 2004 to December 2008. MRSA’s prevalence among strains of S. aureus and the rate of MRSA detection were studied. Identification of MRSA infection is according to the laboratory-based ward liaison surveillance. The minimal inhibitory concentrations (MICs) of vancomycin, teicoplanin, and arbekacin for the various isolates were determined. During the period studied, there were 621 MRSA-positive patients. MRSA prevalence among strains of S. aureus was 45.5% (621/1,365). The rate of MRSA detection in inpatients was 0.953/100 inpatients. Of the 621 patients from whom MRSA was isolated, 51 (8.2%) had an MRSA infection (MRSA infection rate 0.078/100 inpatients). MRSA was often detected from the respiratory tract, but this seldom led to infection, since many of those affected were merely carriers. MICs against MRSA was 0.5–4xa0μg/ml for vancomycin, 0.5–16xa0μg/ml for teicoplanin, and 0.5 to >16xa0μg/ml for arbekacin, with no tendency for tolerance observed for these drugs. Findings suggest that whereas MRSA remains prevalent, there is a low incidence of infection in a general hospital in Japan.

A Normal Range of KL-6/MUC1 Independent of Elevated SP-D Indicates a Better Prognosis in the Patients with Honeycombing on High-Resolution Computed Tomography

Both SP-D and KL-6/MUC1 are established biomarkers of the interstitial pneumonias, including idiopathic pulmonary fibrosis (IPF), but the causes and clinical outcomes based on their independent effects are not known. Eleven asymptomatic patients, detected with honeycombing on high-resolution computed tomography (HRCT), were compared with 17 other IPF outpatients having slight respiratory symptoms and honeycombing as well. Although SP-D was increased in both groups, KL-6 was significantly higher in the symptomatic IPF group. When the patients (n = 11) having both biomarkers elevated were compared with the other patients (n = 6) with only SP-D elevated, the distribution of fibrotic lesions with honeycombing on HRCT was larger and the survival time was shorter in the patients having both biomarkers elevated. Immunohistochemical analysis also differentiated these biomarkers in the lung. These results suggest both a cause and the prognostic value of dissociation of these biomarkers.

Observational study of chemotherapy-induced Clostridium difficile infection in patients with lung cancer

BackgroundDiarrhea post-antibiotic use is primarily attributed to Clostridium difficile infection (CDI)-induced mucosal lesions, and evidence of CDI in patients undergoing chemotherapy without prior antibiotic treatment is also increasing. However, few studies have investigated the relationship between chemotherapy use and diarrhea. This study aimed to determine whether the incidence of CDI increased in patients with lung cancer undergoing chemotherapy even without prior antibiotic treatment.MethodsWe conducted a retrospective study and investigated the presence of Clostridium difficile (C. difficile) and its toxins in patients who experience diarrhea during chemotherapy. If grade 2 or higher diarrhea was noted, a stool culture was performed to detect anaerobic organisms and C. difficile toxins A and B.ResultsA total of 345 consecutive patients (492 in terms of chemotherapy regimens) were enrolled in the study. Grade 2 or higher diarrhea was observed in patients using 36 (7.3%) of these regimens, among which CDI without prior antibiotic exposure was confirmed in patients using 8 regimens (22.2%).ConclusionsCDI may remain undetected in patients undergoing chemotherapy even in those who had not received antibiotic treatment previously, unless due attention is paid to its possibility. Testing for C. difficile toxins is highly recommended to expedite timely treatment for diarrhea in such patients. Further studies are needed to clarify the relationship between chemotherapy drug use and CDI to facilitate prevention.