ABSTRACT: BACKGROUND: Legionella pneumophila is the causative agent of human Legionnaire's disease. During infection, the bacterium invades macrophages and lung epithelial cells, and replicates intracellularly. However, little is known about its interaction with T cells. We investigated the ability of L. pneumophila to infect and stimulate the production of interleukin-8 (IL-8) in T cells. The objective of this study was to assess whether L. pneumophila interferes with the immune system by interacting and infecting T cells. RESULTS: Wild-type L. pneumophila and flagellin-deficient Legionella, but not L. pneumophila lacking a functional type IV secretion system Dot/Icm, replicated in T cells. On the other hand, wild-type L. pneumophila and Dot/Icm-deficient Legionella, but not flagellin-deficient Legionella or heat-killed Legionella induced IL-8 expression. L. pneumophila activated an IL-8 promoter through the NF-kappaB and AP-1 binding regions. Wild-type L. pneumophila but not flagellin-deficient Legionella activated NF-kappaB, p38 mitogen-activated protein kinase (MAPK), Jun N-terminal kinase (JNK), and transforming growth factor beta-associated kinase 1 (TAK1). Transfection of dominant negative mutants of IkappaBalpha, IkappaB kinase, NF-kappaB-inducing kinase, TAK1, MyD88, and p38 MAPK inhibited L. pneumophila-induced IL-8 activation. Inhibitors of NF-kappaB, p38 MAPK, and JNK blocked L. pneumophila-induced IL-8 expression. In addition, c-Jun, JunD, cyclic AMP response element binding protein, and activating transcription factor 1, which are substrates of p38 MAPK and JNK, bound to the AP-1 site of the IL-8 promoter. CONCLUSIONS: Taken together, L. pneumophila induced a flagellin-dependent activation of TAK1, p38 MAPK, and JNK, as well as NF-kappaB and AP-1, which resulted in IL-8 production in human T cells, presumably contributing to the immune response in Legionnaire's disease.

Objective Tuberculosis (TB) in patients undergoing hemodialysis (HD) for end-stage renal disease (ESRD) is commonly thought to be associated with a very poor prognosis. Moreover, it is difficult to diagnose. This report was designed to describe this condition and to determine the mortality rate and risk factors associated with mortality. In addition, the study evaluated the usefulness of QuantiFERON TB-2G((R))(QFT-2G). Methods Retrospective study Patients Patients with confirmed TB admitted between January 2001 and May 2009 were retrospectively identified and enrolled. The clinical, radiological, and bacteriological data at the time of admission were recorded. A multivariate analysis was performed to identify the predictive factors for mortality. Results A total 19 TB patients (6 females; median age, 73 years) were included. TB occurred in most cases within 1.3 years from the initiation of dialysis. Most patients presented with fever (84.2%) and extrapulmonary TB (57.9%). The mortality rate within 24 weeks of the initiation of TB treatment was 36.8%. The factors associated with mortality were: a short duration of dialysis (HR 8.86, 95% CI 1.03-75.7, p=0.04), and underweight (HR 10.88, 95% CI 1.28-92.6, p=0.02). The sensitivity of QFT-2G, acid-fast smear, and polymerase chain reaction was 50, 80, and 88.2% respectively. Conclusion These data indicate a high incidence of TB in the early stages of HD and a high mortality rate among these patients. The clinical utility of QFT-2G was found to be limited. Hypoalbuminemia might therefore be related to either indeterminate or negative results of QFT-2G.

Legionella pneumonia typically presents as lobar pneumonia with multiple-lobe involvement, but Legionella lung abscess is rare. To identify the predisposing factors for Legionella abscess, we analyzed 62 of the 79 case reports on Legionella abscess found in literature; 28 (45.2%) were of hospital-acquired infection and 28 (45.2%), community-acquired infection. Seventeen patients (27.4%) died. L. pneumophila serogroup 1 was the most common, but other serogroups of L. pneumophila, L. micdadei, L. bozemanii, L. dumoffii, and L. maceachernii were also isolated from the abscess. Corticosteroids were administered for underlying diseases to 43 (69.4%) patients. Peripheral neutrophil counts were higher in patients with abscess than in those with only pulmonary infiltration. In certain cases, Legionella abscess developed during neutropenia recovery. However, lymphocyte counts were low in most cases. Clinical factors like corticosteroid treatment, which causes impaired cellular immunity and subsequent neutrophil accumulation in the lesion, might function as predisposing factors for Legionella abscess.

It is well established that diffuse interstitial shadows are observed in human T-cell lymphotropic virus type 1 (HTLV-1) carriers. However, the pathological pattern of nonspecific interstitial pneumonia (NSIP) has rarely been reported. Here, we describe the clinical features of four patients with histologically proven NSIP and HTLV-1 infection. The patients, one woman and three men, had a median age of 59.5 years. High-resolution computed tomography of the lungs was performed in all patients, and no apparent honeycomb formations were detected. The present study demonstrates that the NSIP pattern is a significant pathological classification of interstitial pneumonia associated with HTLV-1 carriers.

A 26-year-old woman with lymphoangioleiomyomatosis (LAM) was hospitalized for the surgical excision of a giant abdominal tumor of right kidney origin. The pathological diagnosis of the tumor was conventional angiomyolipoma (AML). After 8 months, 2 liver tumors appeared and grew rapidly. The tumors were resected, and the pathological finding of these tumors was epithelioid AML. Thereafter, metastatic multiple lung tumors appeared, and there was local recurrence of the liver tumors. Sirolimus, an mTOR protein inhibitor, was used to treat epithelioid AML. However, the drug did not inhibit the rapid growth of the tumor at all. This finding suggests that sirolimus might not be effective against epithelioid AML, and in such cases, complete surgical resection should be the treatment of choice.

A 56-year-old man, having no particular past history, was admitted to our hospital, with a 9-month history of painful ulcerated lesion of the tongue and a 6-month history of productive cough. A physical examination revealed swelling of his cervical lymph nodes, and a chest roentgenogram on admission showed cavities in the both upper lung fields and nodular shadows over the both lung fields. He was initially suspected of having both cancer of the tongue and pulmonary tuberculosis, but finally diagnosed as secondary tuberculosis of the tongue due to sputum smear-positive pulmonary tuberculosis by biopsy of the tongue and sputum examination. He was treated with isoniazid, rifampicin, ethambutol and pyrazinamide, and his pain and ulcerated lesion of the tongue rapidly improved. Due to our search for recent 16 cases of tuberculosis of the tongue in Japan, we found that the patients of tuberculosis of the tongue were more likely to have concurrently sputum smear-positive pulmonary tuberculosis. In some cases, the delay in diagnosis was seen. These cases suggest that refractory ulcerated cases of the tongue should be subjected to the biopsy and examination for acid fast bacilli of the tongue with suspicion of tuberculosis of the tongue, and then a chest roentgenogram with suspicion of pulmonary tuberculosis.

The incidence of influenza in the Naha city area in the southernmost part of Japan was surveyed in 2007 and 2008. Patients who had influenza-like symptoms and visited one of four general hospitals in Naha City, Okinawa, Japan were included in this study. The nasal or throat swab samples were applied to the rapid test for detecting influenza A and B virus antigens. The positive rate of influenza A and/or B virus antigen was 26.2%(8,480/32,380). Most cases (82.9%) were influenza A. In 2007, influenza A cases were detected during the entire year, and an epidemic peak was also noted in July, while no outbreak occurred in the summer of 2008. The surveillance of the rapid influenza virus antigen test seemed to provide reliable epidemiological data. This finding warrants further study in this region, including study of the influences of climate and socio-behavior patterns of the residents in the region on influenza epidemics.

A 49-year-old woman with poorly controlled type 2 diabetes mellitus was admitted to hospital complaining of fever, vomiting, and lower abdominal pain. Laboratory investigation revealed leukocytopenia, high blood sugar, and pyuria. Pyelonephritis was then diagnosed. Escherichia coli was isolated from blood and urinary cultures. In spite of antimicrobial therapy, the patient's condition deteriorated. A computed tomography scan of the abdomen on the second day of hospitalization revealed the presence of air in the collecting system of the left kidney. Emphysematous pyelonephritis was diagnosed, and a renoureteral catheter was promptly inserted via the left ureter into the affected pelvis of the left kidney. Imipenem, cefotiam, and levofloxacin were administered during the clinical course. This early intervention and the appropriate antimicrobial therapy were effective in resolving the infection. Urinary tract infections should be carefully managed in patients with poorly controlled diabetes mellitus.

BACKGROUND: Human T lymphotropic virus type I (HTLV-I), the cause of human T cell leukemia, is associated with a high incidence of several other infectious diseases. However, the relationship between pulmonary infections and HTLV-I infection is still unclear. OBJECTIVE: A large-scale retrospective study was conducted on hospital inpatients to evaluate the relationship between community-acquired pneumonia (CAP) and HTLV-I infection. METHODS: The present study included 4,666 hospitalized patients during 1991-2007. Three hundred and thirteen of them were diagnosed as CAP. The presence of serum HTLV-I antibody was determined in all patients on admission. Prevalence of HTLV-I infection was analyzed between CAP patients and all inpatients. We also compared HTLV-I-positive CAP patients and HTLV-I-negative CAP patients for severity and manifestation of pneumonia. RESULTS: The prevalence of HTLV-I was higher in CAP patients than in all inpatients (18.9%: 13.7%, p=0.011). The rates of renal diseases and collagen vascular disorders were higher in the HTLV-I-positive CAP patients than in the HTLV-I-negative CAP patients. Multivariate analysis revealed that HTLV-I infection, gender, COPD and collagen vascular disorders were all independent risk factors for CAP. The severity indices of CAP, the PORT score and the CURB-65 score, were higher in the HTLV-I-positive patients than in the HTLV-I-negative patients. CONCLUSION: This study demonstrates that HTLV-I infection might be an independent risk factor for CAP and that HTLV-I-infected patients tend to demonstrate a relatively severe form of pneumonia.