• Tuberculosis and Respiratory Diseases
• /
• v.43 no.6
• /
• pp.833-841
• /
• 1996

• IMMUNE NETWORK
• /
• v.21 no.6
• /
• pp.40.1-40.20
• /
• 2021

Mycobacteroides abscessus (previously Mycobacterium abscessus; Mabc), one of rapidly growing nontuberculous mycobacteria (NTM), is an important pathogen of NTM pulmonary diseases (NTM-PDs) in both immunocompetent and immunocompromised individuals. Mabc infection is chronic and often challenging to treat due to drug resistance, motivating the development of new therapeutics. Despite this, there is a lack of understanding of the relationship between Mabc and the immune system. This review highlights recent progress in the molecular architecture of Mabc and host interactions. We discuss several microbial components that take advantage of host immune defenses, host defense pathways that can overcome Mabc pathogenesis, and how host-pathogen interactions determine the outcomes of Mabc infection. Understanding the molecular mechanisms underlying host-pathogen interactions during Mabc infection will enable the identification of biomarkers and/or drugs to control immune pathogenesis and protect against NTM infection.

• Journal of Chest Surgery
• /
• v.34 no.7
• /
• pp.539-546
• /
• 2001

Background: Pulmonary complications in immunocompromised patients are often fatal. Empirical treatment is usually applied based on the clinical and radiological findings because of the risk of the aggressive diagnostic procedures such as open lung biopsy. However, recent advancements in operative procedures and perioperative management has decreased the procedure-related risks. We have prospectively analyzed the risks and benefits of the early application of open lung biopsy in such patients. Material and Method: Forty-two consecutive immunocompromised patients with critical pulmonary complications were included from June, 1996 to December, 1999. The definition of the immunocompromised is as those with chemotherapy and/or other modality for hematologic disorders, with usage of immunosuppressive drug after transplantation, with usage of steroid for more than 1 month, and with primary immunodeficiency disorders. The indication of open lung biopsy was those with no significant improvement after a week of aggressive application of empirical treatment or with rapidly aggressive process. The underlying disease included hematologic disorder(31 patients), post-transplantation(3 patients), chemotherapy for solid tumor(2 patients), and others(6 patients). Operations were done through thoracotomy(conventional or mini-) or VATS.

• Tuberculosis and Respiratory Diseases
• /
• v.83 no.2
• /
• pp.132-140
• /
• 2020

In human immunodeficiency virus (HIV)-infected patients, Pneumocystis jirovecii pneumonia (PCP) is a well-known opportunistic infection and its management has been established. However, PCP is an emerging threat to immunocompromised patients without HIV infection, such as those receiving novel immunosuppressive therapeutics for malignancy, organ transplantation, or connective tissue diseases. Clinical manifestations of PCP are quite different between patients with and without HIV infections. In patients without HIV infection, PCP rapidly progresses, is difficult to diagnose correctly, and causes severe respiratory failure with a poor prognosis. High-resolution computed tomography findings are different between PCP patients with HIV infection and those without. These differences in clinical and radiological features are due to severe or dysregulated inflammatory responses that are evoked by a relatively small number of Pneumocystis organisms in patients without HIV infection. In recent years, the usefulness of polymerase chain reaction and serum β-D-glucan assay for rapid and non-invasive diagnosis of PCP has been revealed. Although corticosteroid adjunctive to anti-Pneumocystis agents has been shown to be beneficial in some populations, the optimal dose and duration remain to be determined. Recent investigations revealed that Pneumocystis colonization is prevalent and that asymptomatic carriers are at risk for developing PCP and can serve as the reservoir for the spread of Pneumocystis by airborne transmission. These findings suggest the need for chemoprophylaxis in immunocompromised patients as well as infection control measures, although the indications remain controversial. Because a variety of novel immunosuppressive therapeutics have been emerging in medical practice, further innovations in the diagnosis and treatment of PCP are needed.

• Pediatric Infection and Vaccine
• /
• v.27 no.3
• /
• pp.190-197
• /
• 2020

Laryngotracheobronchitis (LTB) is a common disease in the pediatric population, and it is rarely caused by a fungal infection. Acute respiratory failure caused by fungal LTB mainly occurs in immunocompromised patients, and early diagnosis is closely associated with morbidity and mortality. However, an appropriate diagnosis is challenging for pediatricians because symptoms and signs of LTB caused by Aspergillus spp. are nonspecific. Here, we report a case of progressive respiratory failure caused by pseudomembranous LTB in a child with a suspicion of primary immunodeficiency and highlight the importance of an early investigation, especially in immunocompromised patients.

• Korean Journal of Radiology
• /
• v.25 no.5
• /
• pp.481-492
• /
• 2024

Objective: To evaluate the clinical and imaging characteristics of SARS-CoV-2 breakthrough infection in hospitalized immunocompromised patients in comparison with immunocompetent patients. Materials and Methods: This retrospective study analyzed consecutive adult patients hospitalized for COVID-19 who received at least one dose of the SARS-CoV-2 vaccine at two academic medical centers between June 2021 and December 2022. Immunocompromised patients (with active solid organ cancer, active hematologic cancer, active immune-mediated inflammatory disease, status post solid organ transplantation, or acquired immune deficiency syndrome) were compared with immunocompetent patients. Multivariable logistic regression analysis was performed to evaluate the effect of immune status on severe clinical outcomes (in-hospital death, mechanical ventilation, or intensive care unit admission), severe radiologic pneumonia (≥ 25% of lung involvement), and typical CT pneumonia. Results: Of 2218 patients (mean age, 69.5 ± 16.1 years), 274 (12.4%), and 1944 (87.6%) were immunocompromised an immunocompetent, respectively. Patients with active solid organ cancer and patients status post solid organ transplantation had significantly higher risks for severe clinical outcomes (adjusted odds ratio = 1.58 [95% confidence interval {CI}, 1.01-2.47], P = 0.042; and 3.12 [95% CI, 1.47-6.60], P = 0.003, respectively). Patient status post solid organ transplantation and patients with active hematologic cancer were associated with increased risks for severe pneumonia based on chest radiographs (2.96 [95% CI, 1.54-5.67], P = 0.001; and 2.87 [95% CI, 1.50-5.49], P = 0.001, respectively) and for typical CT pneumonia (9.03 [95% CI, 2.49-32.66], P < 0.001; and 4.18 [95% CI, 1.70-10.25], P = 0.002, respectively). Conclusion: Immunocompromised patients with COVID-19 breakthrough infection showed an increased risk of severe clinical outcome, severe pneumonia based on chest radiographs, and typical CT pneumonia. In particular, patients status post solid organ transplantation was specifically found to be associated with a higher risk of all three outcomes than hospitalized immunocompetent patients.

• Journal of Yeungnam Medical Science
• /
• v.37 no.1
• /
• pp.63-66
• /
• 2020

Purulent pericarditis is defined as a localized pericardial infection with gross pus formation in the pericardial space. Although purulent pericarditis is now rare in the antibiotic era, it may be life-threatening. We describe a rare case of purulent pericarditis that originated from a subdiaphragmatic suppurative focus in an immunocompromised host.

• Tuberculosis and Respiratory Diseases
• /
• v.77 no.5
• /
• pp.223-226
• /
• 2014

Aspergillus tracheobronchitis is a form of invasive pulmonary aspergillosis in which the Aspergillus infection is limited predominantly to the tracheobronchial tree. It occurs primarily in severely immunocompromised patients such as lung transplant recipients. Here, we report a case of Aspergillus tracheobronchitis in a 42-year-old man with diabetes mellitus, who presented with intractable cough, lack of expectoration of sputum, and chest discomfort. The patient did not respond to conventional treatment with antibiotics and antitussive agents, and he underwent bronchoscopy that showed multiple, discrete, gelatinous whitish plaques mainly involving the trachea and the left bronchus. On the basis of the bronchoscopic and microbiologic findings, we made the diagnosis of Aspergillus tracheobronchitis and initiated antifungal therapy. He showed gradual improvement in his symptoms and continued taking oral itraconazole for 6 months. Physicians should consider Aspergillus tracheobronchitis as a probable diagnosis in immunocompromised patients presenting with atypical respiratory symptoms and should try to establish a prompt diagnosis.

• BMB Reports
• /
• v.47 no.4
• /
• pp.184-191
• /
• 2014

Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in infants and young children. Severe clinical manifestation of RSV infection is a bronchiolitis, which is common in infants under six months of age. Recently, RSV has been recognized as an important cause of respiratory infection in older populations with cardiovascular morbidity or immunocompromised patients. However, neither a vaccine nor an effective antiviral therapy is currently available. Moreover, the interaction between the host immune system and the RSV pathogen during an infection is not well understood. The innate immune system recognizes RSV through multiple mechanisms. The first innate immune RSV detectors are the pattern recognition receptors (PRRs), including toll-like receptors (TLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), and nucleotide-biding oligomerization domain (NOD)-like receptors (NLRs). The following is a review of studies associated with various PRRs that are responsible for RSV virion recognition and subsequent induction of the antiviral immune response during RSV infection.

• Korean Journal of Pharmacognosy
• /
• v.40 no.1
• /
• pp.35-40
• /
• 2009

The immunomodulatory activities of the ethanol extract of Gynostemma pentaphyllum, termed hereafter as GPE, were examined in immunosuppressed mice as well as in normal mice in the present study. Oral administration of GPE into mice prevented dexamethasone (DEX)-induced immunosuppression as determined by the mitogen-induced proliferation of the splenocytes and the the cytokine production (TNF-$\alpha$, IL-$1{\beta}$) in the whole blood culture. In addition, oral administration of GPE increased antitumor host defense in mice implanted with sarcoma-180 tumor cells. The immunoaugmenting activity of orally administered GPE was also confirmed in mice immunized with ovalbumin (OVA). Mice that were orally administered with GPE generated much more potent OVA-specific cytotoxic T lymphocyte (CTL) responses upon intravenous OVA injection compared to the untreated controls. These results demonstrate that oral administration of the ethanol extract of Gynostemma pentaphyllum could be useful to increase host defense in immunocompromised situations such as stress- or tumor-induced immunosuppression.