Yuji Watanuki

Screening of tuberculosis by interferon-γ assay before biologic therapy for rheumatoid arthritis

Infection with Mycobacterium tuberculosis (M. tuberculosis) is a critical complication in anti-TNF therapies. In 141 BCG vaccinated healthy individuals and 71 rheumatoid arthritis (RA) patients as screening before anti-TNF therapies, M. tuberculosis specific immune responses were evaluated by tuberculin skin test (TST) and enzyme-linked immunospot assay (ELISPOT), which detected antigen specific IFN-gamma secreting cells in peripheral blood mononuclear cells simulated with either purified protein derivative (PPD), early secretory antigen target 6 (ESAT-6) or culture filtrate protein 10 (CFP-10). Induration over 5 mm in TST was found in 87.9% of controls and 21.4% of RA patients. Erythema size in TST was significantly suppressed in RA patients, especially those receiving prednisolone (PSL), whereas the PPD specific IFN-gamma secretion was less attenuated. Significant responses to either ESAT-6 or CFP-10 in ELISPOT were detected in 14.1% of RA patients including those having positive TST, while the ELISPOT assay was negative in all healthy individuals and 73.3% of RA patients having positive TST. Of ELISPOT positive RA patients, mean dosage of PSL was 4.58 mg and 1.25 mg in TST negative and positive patients, respectively. Thus, ELISPOT is useful for screening of tuberculosis in RA patients, even in those receiving corticosteroids.

Potential clinical benefit of the in situ hybridization method for the diagnosis of sepsis

Despite the significant development of antibiotics, sepsis is still associated with high morbidity and mortality rates. The identification of pathologic organisms at an early stage of sepsis is critical to improve the outcome, but this is difficult to achieve with the conventional method of blood culture (BC). It has been demonstrated that the genes of pathogenic organisms surviving in neutrophils were detectable with in situ hybridization (ISH) and this method was useful for the accurate and rapid diagnosis of sepsis. In this study, we applied ISH to blood smears 60 patients with suspected sepsis. BC was also carried out using the same blood samples to investigate the diagnostic value of ISH. The number of positive results obtained by ISH was approximately four times higher than that obtained by BC (ISH, 25 [41.7%]; BC, 7 [11.7%]). The positive rate in the 21 patients given antibiotics was 61.9% by ISH (13 patients) and 4.7% by BC (1 patient). The antibiotic treatments targeting the organisms detected by either procedure showed a beneficial clinical outcome. Positive results by ISH were obtained earlier than those with BC (ISH, within 1 day; BC, several days). We conclude that ISH is a useful method for the rapid diagnosis of sepsis.

The efficacy of high-dose penicillin for community-acquired pneumonia diagnosed by pneumococcal urine antigen test

We analyzed the efficacy of both the Streptococcus pneumoniae urine antigen test as a quick diagnostic tool and the administration of high-dose penicillin in response to a positive S. pneumoniae urine antigen test. We conducted a retrospective analysis of 48 cases of pneumococcal pneumonia, in which the patients were treated with high-dose penicillin. All the cases were diagnosed by a positive urine antigen test. Treatment with high-dose penicillin was effective in 43 of the 48 patients. This treatment was also effective in 12 of 16 culture-confirmed cases with low susceptibility to penicillin. Eleven patients who were positive for the S. pneumoniae urine antigen test but culturenegative showed clinical improvement with high-dose penicillin. Pneumonia caused by S. pneumoniae appeared to be treated safely and effectively with high-dose penicillin based on positive results of the urine antigen test, as penicillin resistance was unlikely to be a problem.

Fatal aspiration of sardine fry in a patient with lung cancer.

We report a fatal case of death due to unusual aspiration of sardine fry in an elderly Japanese man with lung cancer. The cause of death was sudden respiratory arrest while eating. Autopsy revealed peculiar materials with cell nests and pigmented particles, together with striated muscle and skin, in the ectatic bronchioles of the left lower lobe. Serial histologic sections suggested that the structures observed were the eyeballs of small animals that appeared to have been inhaled. The patient had habitually eaten sardine fry and rice gruel, which were also detected in the gastric contents. Therefore, the eyes were considered to be those of the fry, which is a popular food item in Japan. This was confirmed by histologic examination of fry that were obtained commercially.

Clinical efficacy of carbapenems on hospital-acquired pneumonia in accordance with the Japanese Respiratory Society Guidelines for management of HAP

Hospital-acquired pneumonia (HAP) is the second most common cause of hospital-acquired infection and is the leading cause of death. In 2002, the Japanese Respiratory Society (JRS) published guidelines for the diagnosis and treatment of HAP (JRS GL 2002). In these guidelines, treatment with carbapenems is recommended for all disease types of HAP, excluding cases of mild or moderate pneumonia with no risk factors, and cases with early-onset ventilation-acquired pneumonia. To evaluate the efficacy of carbapenems on HAP in accordance with JRS GL 2002, we conducted a prospective study of HAP patients treated with carbapenems based on JRS GL 2002. The results of this study were also analyzed based on the revised guidelines published in June 2008 (JRS GL 2008), and the validity of the new guidelines was examined. Of the 33 subjects, 19 were judged as responders to the treatment, corresponding to a response rate of 57.6%. There were 3 deaths, corresponding to a mortality rate of 9.1%. The efficacy of carbapenems for the treatment of HAP based on JRS GL 2002 was confirmed. The severity rating system in JRS GL 2002 has a tendency to overestimate the severity of the cases and may lead to overtreatment in some cases. On the other hand, the severity rating system by JRS GL 2008 seemed to be more accurate and closely correlated with the efficacy of the treatment. It is suggested that JRS GL 2008 is more useful in clinical practice for accurately judging the severity of the disease and initiating appropriate subsequent antibiotic therapy.

High frequency of β-lactamase-negative, ampicillin-resistant strains of Haemophilus influenzae in patients with chronic bronchitis in Japan

In Japan, the increasing incidence of β-lactum-resistant Haemophilus influenzae infections is of growing concern. We retrospectively studied whether the prevalence of β-lactamase-negative ampicillin-resistant strains of H. influenzae was influenced by chronic lung diseases. H. influenzae isolates, obtained from patients who were diagnosed with acute or chronic bronchitis, or acute exacerbation of chronic bronchitis in 2005, were studied. In addition to susceptibility testing, polymerase chain reaction (PCR) was performed for the detection of TEM-1 β-lactamase, and Asn526-Lys and Ser385-Thr amino acid substitutions in the ftsI gene encoding penicillin-binding protein-3 (PBP-3). The minimum inhibitory concentration values of β-lactams were found to be increased in isolates from patients with chronic bronchitis who had been repeatedly administered antibiotics. Genetic analysis using PCR suggested that this might be associated with a high frequency of β-lactamase-negative strains with mutations in PBP-3. The presence of β-lactum-resistant strains needs to be considered for patients with chronic bronchitis in whom H. influenzae is isolated as a causative pathogen.

Phase I/II trial of docetaxel and carboplatin in previously untreated patients with advanced non-small-cell lung cancer

AbstractBackground. This trial was conducted to determine the maximum tolerated dose (MTD) and principal toxicities of combinations of docetaxel and carboplatin administered every 3 weeks to patients with advanced non-small-cell lung cancer (NSCLC) previously untreated with chemotherapy, and to find suitable doses for phase II studies in Japanese subjects. Methods. Japanese patients with advanced NSCLC and performance status 0 to 2 according to the World Health Organization classification, but previously untreated with chemotherapy received docetaxel followed by carboplatin, each infused over a 1-h period. The carboplatin dose was based on the target area under the curve (AUC), using Calverts formula. Dose levels studied were: docetaxel (mg/m2)/carboplatin AUC (mg/ml·min), 50/4, 60/4, and 60/5, repeated every 3 weeks. Granulocyte-colony stimulating factor (G-CSF) support was first used when dose-limiting toxicities (DLTs) were encountered. Results. Of 14 patients entered, 12 were assessable for toxicity and response. The MTD schedule was: docetaxel, 60 mg/m2, with carboplatin, AUC 5 mg/ml·min (DLTs in 3 of 3 patients). The recommended dosage was: docetaxel, 60 mg/m2, with carboplatin, AUC 4 mg/ml·min (DLTs in 2 of 6 patients). The main toxic effect was neutropenia, and any nonhematologic toxic effects were mild. No thrombocytopenia occurred. Six of the 12 patients (50%) showed responses; 4 of the 6 at the recommended doses. Conclusion. Docetaxel 60 mg/m2, given over a 1-h period, followed by carboplatin, AUC 4 mg/ml·min, given over a 1-h period, is recommended for phase II studies in Japan. This combined chemotherapy has mild toxicity, except for neutropenia, and is useful and easy to administer. We therefore believe that phase II and phase III studies of this therapy would be well justified.