Purpose: This study aimed to assess the survival rate (SR) and death risk for associated pulmonary arterial hypertension (aPAH; 10th revision of the International Statistical Classification of Diseases [ICD-10], I27.2) in Koreans.Methods: The data were collected from the Korean National Health Insurance Service from 2006 through 2017 (n= 15,448). We analyzed the SR using the Kaplan-Meier method and carried out Cox proportional hazards analyses.Results: Patients’ mean age upon aPAH diagnosis was 60.1±24.0 years, and 60.7% of the patients were female. The 10-year SR of aPAH was 46.3% (95% confidence interval, 45.0 to 47.6). The factors associated with an increase in the adjusted death risk included age of 0 to 9 years, advancing age, male sex, lower income level, and comorbidities including diabetes mellitus, myocardial infarction, heart failure, hemorrhagic stroke, chronic kidney disease, malignant neoplasm, hereditary hemorrhagic telangiectasia, and systemic lupus erythematosus.Conclusion: The 10-year SR of aPAH was over 46%. The risk of death from aPAH was significantly higher with advancing age, sex, lower income level, and comorbidities.

Paraneoplastic neurological syndromes (PNS) are rare and often severe neurological complications of malignancies, significantly impacting patient prognosis and quality of life. They are characterized by a diverse range of onconeural autoantibodies, with further discoveries likely due to ongoing research. Among these, high-risk autoantibodies primarily target intracellular neural cell antigens. We present cases of lung cancer patients who developed limbic encephalitis and seizures at diagnosis, suggestive of PNS. Each case demonstrated distinct autoantibody profiles. Recognition of these potentially life-altering neurological sequelae, as paraneoplastic manifestations of malignancies, is crucial for physicians. PNS may precede primary cancer diagnosis and substantially affect patient presentation and overall outcome. We provide in detail the diagnostic work-up and available treatment options for these complex cases.

Central nervous system (CNS) metastases, including brain and leptomeningeal metastasis, are associated with poor prognosis in epidermal growth factor receptor (<i>EGFR</i>)-mutated non-small cell lung cancer (NSCLC) patients. CNS metastasis occurs in more than 50% of <i>EGFR</i>-mutated NSCLC cases during the treatment course. The treatment options for CNS metastases in these patients are limited, and there have been ongoing efforts to develop targeted agents with enhanced CNS penetration. AZD3759 (zorifertinib) is a novel <i>EGFR</i> tyrosine kinase inhibitor with a high capability of CNS penetration and proven efficacy with tolerable safety profiles. In this report, we describe a case of a patient with <i>EGFR</i>-mutant NSCLC that was initially diagnosed with multiple brain metastasis who demonstrated prolonged response of both intra- and extracranial lesions over 7 years with AZD3759 as first-line treatment.

Purpose: Colistin heteroresistance mediates the failure of antibiotic treatments, is prone to lead to colistin resistance, and has been frequently reported in <i>Klebsiella pneumoniae</i>. This study investigated origins of the increase in colistin resistance following colistin exposure to colistin-heteroresistant <i>K. pneumoniae</i>.Methods: A modeled colistin-heteroresistant <i>K. pneumoniae</i> strain (i.e., mimicking colistin- heteroresistant [m-CL<sup>HR</sup>]) was generated using a susceptible <i>K. pneumoniae</i> strain ATCC 10031 and its resistance-induced mutant. Heteroresistance patterns were investigated through population analysis profiling (PAP), competition assays, and fluctuation and stability tests. An <i>in vitro</i> time-killing assay for colistin was performed for the m-CL<sup>HR</sup> to identify the change in susceptible and resistant populations before and after colistin exposure.Results: The generated m-CL<sup>HR</sup> strain showed a typical heteroresistance pattern for colistin in PAP, and its competition assay did not show fitness costs for any population. The ratio of resistant cells to susceptible cells did not deviate significantly from the range of heteroresistance in the fluctuation test, while the ratios of resistant cells preserved their stability. The <i>in vitro</i> time-killing assay thus showed that the resistant cells increased upon colistin exposure; sequencing analyses confirmed that the surviving resistant cells did not originate from susceptible cells by mutation. This study successfully modeled a colistin-heteroresistant <i>K. pneumoniae</i> strain, i.e., m-CL<sup>HR</sup>.Conclusion: In this modeled heteroresistant strain, only the colistin-resistant population survived the colistin treatment—this suggests that the development of colistin resistance from heteroresistant strain is because of the selection of a resistant population and not by the induction of resistance through mutations in susceptible populations.

The onset of puberty is a pivotal developmental milestone, and the release of gonadotropin-releasing hormone (GnRH) and luteinizing hormone is a key factor in the initiation of puberty. Both kisspeptin and its receptor (KISS1) and KISS1 receptor (KISS1R) play significant roles in regulating GnRH release, and consequently, the initiation of puberty. Central precocious puberty (CPP) is a condition in which the development of puberty is driven by the premature activation of the hypothalamic-pituitary-gonadal axis. In girls, CPP is primarily idiopathic, and genetic and epigenetic aspects of <i>KISS1</i> and <i>KISS1R</i> have been implicated in its etiology. This review aimed to provide an overview of the current knowledge regarding mutations and polymorphisms in <i>KISS1</i> and <i>KISS1R</i> associated with CPP. Additionally, this study provides a comprehensive review of the epigenetic regulation of the <i>KISS1</i> gene in the context of puberty onset and CPP.

Acute invasive fungal sinusitis (AIFS) is a rapidly progressing, life-threatening infection. The advent of immunomodulatory therapies has expanded the population susceptible to AIFS. In this case report, we describe a patient who defies the conventional profile of AIFS. This 70-year-old woman is immunocompetent and non-diabetic, with a history of multiple sclerosis (MS) and ongoing treatment with glatiramer acetate (GA), immunomodulator. She came to the emergency room due to acute vision changes, and images revealed an enhancing mass in the left pterygopalatine fossa. The diagnosis of AIFS was confirmed by biopsy in the operating room. Subsequently, anti-fungal therapies were initiated with a follow-up operative debridement. Follow-up magnetic resonance imaging (10 months since treatment) showed no progression of AIFS. GA was discontinued since the diagnosis, and MS has remained stable. Recognizing this unique group of atrisk patients is crucial, as early detection and treatment play a pivotal role in preventing significant morbidity and mortality.

A 70-year-old male with risk factors for vascular disease presented with dizziness and instability. The patient showed horizontal geotropic nystagmus when turning his head while lying down, with larger slow phase velocity observed when turning to the left. There were no other neurological deficits. Video head impulse tests and vestibular evoked myogenic potentials were normal. The initial magnetic resonance imaging (MRI) findings were negative; however, the patient experienced subsequent right-side weakness, right tilting, and recurrent episodes of vertigo. A follow-up MRI revealed an acute left medial medullary infarction, which seems to have caused the paroxysmal geotropic central positional nystagmus in this patient.

Crohn’s disease (CD) is a type of inflammatory bowel disease (IBD) characterized by chronic granulomatous inflammation of any part of the body, primarily the gastrointestinal (GI) tract, and is increasing in incidence worldwide. As CD is a systemic disease, the features of CD typically manifest in the GI tract; however, a variety of extra-intestinal manifestations, such as the involvement of joints, skin, and eyes may also occur. Although pyogenic liver abscess itself is rare in the general population (approximately 3–5 per 100,000 hospital admissions), it is also an unusual and rare presentation in pediatric CD patients. In this report, we present a case of pyogenic liver abscess in a 7-year-old female CD patient and discuss the clinical features, laboratory findings, imaging studies, and pathologic report of liver biopsy.

Leukemia and Crohn’s disease are both diseases that can be influenced by genetic factors. Tuberous sclerosis complex (TSC) is a rare autosomal dominant neurogenetic disorder caused by genetic mutation. This report presents a pediatric case of concomitant development of leukemia, Crohn’s disease, and TSC. We aimed to study the pathogenesis of each disease and report this case to provide data for future reports and research on correlation of these three diseases.