Yuichiro Tamaki

Immunopathological characteristics of immune reconstitution inflammatory syndrome caused by Mycobacterium parascrofulaceum infection in a patient with AIDS.

Immune reconstitution inflammatory syndrome (IRIS) caused by mycobacterium in patients with AIDS is often experienced in clinical practice. There is, however, a paucity of data documenting the histopathological findings and the pathogenesis. We determined the immunopathological characteristics of IRIS associated with Mycobacterium parascrofulaceum infection in an AIDS patient. A patient presented with pulmonary lymphadenitis and involvement of the pulmonary lingular segment. Portions of the involved lymph nodes and lung were excised, and the immunological properties were analyzed by immunohistochemical assays. The histological characteristics of lymph nodes showed a caseous necrosis. Histopathologically, the pulmonary lesion was composed of exudative and proliferative lesions. CD4(+), CD8(+), CD57(+), and CD25(+)/FoxP3(+) cells were observed in both types of lesions. Clusters of CD20(+) cells and GATA3(+) cells were predominantly observed in exudative lesions, while T-bet(+) cells were dominant in proliferative lesions. ROR-γ(+) cells were also observed in exudative lesions. These results indicate that the cellular immunity to mycobacteria was recovering in the lung tissue. In M. parascrofulaceum pulmonary infection, the exudative lesion had characteristics of Th2 and Th17-type immunities. In contrast, the proliferative lesion had characteristics of Th-1 type immunity. Our data provide the first evidence to reveal the status of the axis of distinctive immunity in the process of granuloma formation caused by a mycobacterium-related infection.

Hepatocyte growth factor levels in Legionella pneumonia: a retrospective study.

BackgroundHepatocyte growth factor (HGF) is known to be involved in the resolution of pulmonary inflammation and repair of acute lung injury. Legionella pneumonia is sometimes complicated by acute lung injury. Our study aimed to determine the role of serum HGF levels in Legionella pneumonia.MethodsSera from patients with Legionella pneumonia (42 cases), other bacterial pneumonia (33 cases), pulmonary tuberculosis (19 cases), and normal controls (29 cases) were collected. The serum HGF levels for each serum sample were determined by sandwich ELISA. Clinical and laboratory data were collected by reviewing the medical charts.ResultsSerum HGF levels were higher in patients with Legionella pneumonia than in those with other bacterial pneumonia, pulmonary tuberculosis, and controls. The HGF levels were compared with white blood cell counts, C-reactive protein, Alanine amino- transferase, and lactate dehydrogenase (LDH). The HGF levels were correlated to serum LDH levels. Moreover, serum HGF levels were significantly higher in non-survivors than in survivors.ConclusionsHGF levels increased in severer pneumonia caused by Legionella, suggesting that HGF might play a significant role in the Legionella pneumonia.

Surface electromyographic evaluation of the neuromuscular activation of the inspiratory muscles during progressively increased inspiratory flow under inspiratory-resistive loading

This study aimed to evaluate neuromuscular activation in the scalene and sternocleidomastoid muscles using surface electromyography (EMG) during progressively increased inspiratory flow, produced by increasing the respiratory rate under inspiratory-resistive loading using a mask ventilator. Moreover, we attempted to identify the EMG inflection point (EMGIP) on the graph, at which the root mean square (RMS) of the EMG signal values of the inspiratory muscles against the inspiratory flow velocity acceleration abruptly increases, similarly to the EMG anaerobic threshold (EMGAT) reported during incremental-resistive loading in other skeletal muscles. We measured neuromuscular activation of healthy male subjects and found that the inspiratory flow velocity increased by approximately 1.6-fold. We successfully observed an increase in RMS that corresponded to inspiratory flow acceleration with ρ ≥ 0.7 (Spearmans rank correlation) in 17 of 27 subjects who completed the experimental protocol. To identify EMGIP, we analyzed the fitting to either a straight or non-straight line related to the increasing inspiratory flow and RMS using piecewise linear spline functions. As a result, EMGIP was identified in the scalene and sternocleidomastoid muscles of 17 subjects. We believe that the identification of EMGIP in this study infers the existence of EMGAT in inspiratory muscles. Application of surface EMG, followed by identification of EMGIP, for evaluating the neuromuscular activation of respiratory muscles may be allowed to estimate the signs of the respiratory failure, including labored respiration, objectively and non-invasively accompanied using accessory muscles in clinical respiratory care.

Successful conservative management of a case of caustic esophagitis based on computed tomography assessment

We describe the case of a female patient who ingested approximately 100 mL of toilet bowl cleaner containing 9.5% hydrochloric acid in a suicide attempt. Upon admission for hematemesis and epigastric pain, she was alert and oriented with stable vital signs. Initial contrast‐enhanced computed tomography (CT) demonstrated edematous changes with no evidence of upper gastrointestinal tract perforation. Endoscopy was not performed owing to the high risk of perforation. We managed this patient conservatively. Repeat contrast‐enhanced CT revealed mediastinal emphysema on day 2, which resolved by day 6. The patient was subsequently discharged with no apparent strictures of the upper gastrointestinal tract.