Development of a user-friendly training software for pharmacokinetic concepts and models

Although there are many commercially available training software programs for pharmacokinetics, they lack flexibility and convenience. In this study, we develop simulation software to facilitate pharmacokinetics education. General formulas for time courses of drug concentrations after single and multiple dosing were used to build source code that allows users to simulate situations tailored to their learning objectives. A mathematical relationship for a 1-compartment model was implemented in the form of differential equations. The concept of population pharmacokinetics was also taken into consideration for further applications. The source code was written using R. For the convenience of users, two types of software were developed: a web-based simulator and a standalone-type application. The application was built in the JAVA language. We used the JAVA/R Interface library and the ‘eval()’ method from JAVA for the R/JAVA interface. The final product has an input window that includes fields for parameter values, dosing regimen, and population pharmacokinetics options. When a simulation is performed, the resulting drug concentration time course is shown in the output window. The simulation results are obtained within 1 minute even if the population pharmacokinetics option is selected and many parameters are considered, and the user can therefore quickly learn a variety of situations. Such software is an excellent candidate for development as an open tool intended for wide use in Korea. Pharmacokinetics experts will be able to use this tool to teach various audiences, including undergraduates.

A Case of Cerebellopontine Angle Diffuse Large B Cell Lymphoma in a Systemic Lupus Erythematosus Patient / 대한내과학회지

Patients with systemic lupus erythematosus (SLE) are at higher risk for malignant lymphomas, among which, however, primary CNS lymphoma (PCNSL) is rare. PCNSL usually occurs within the cerebral hemispheres, occasionally in the cerebellum, but rarely in the cerebellopontine angle (CPA). We report our findings in a 45-year-old man with SLE on azathioprine, who presented with sudden hearing loss and dysphagia. The brain MRI revealed a mass lesion in the right CPA. A biopsy was performed and the final diagnosis was diffuse large B cell lymphoma. This is the first report of CPA lymphoma in a SLE patient. The patient was treated with whole brain radiotherapy only because of recurrent pneumonia that was a result of dysphagia from permanent cranial nerve injury. He has been in complete remission for over 10 months.

Asymptomatic Isolate Tricuspid Regurgitation with Chordae Tendineae Rupture Caused by Blunt Chest Injury / 영남의대학술지

The incidence and importance of tricuspid valve regurgitation after a blunt chest injury has risen with the increase in the number of automobile accidents and steering wheel traumas. This kind of injury has been reported more frequently in the last decade because of the better diagnostic procedures and understanding of the pathology. However, tricuspid valve regurgitation following a blunt chest injury can still be easily missed because most patients do not show symptoms at the time of the trauma. A 55-year-old male patient presented himself at our facility after suffering a chest injury from an automobile accident. His transthoracic echocardiography (TTE) revealed severe tricuspid valve regurgitation due to the prolapse of his anterior valve leaflet. We report a case of asymptomatic tricuspid regurgitation that developed after a blunt chest injury.

A Case of Pseudohyperphosphatemia in a Patient with Multiple Myeloma / 대한내과학회지

Hyperphosphatemia develops when there is impaired renal phosphate excretion or massive extracellular fluid phosphate load. For example, renal insufficiency, hypoparathyroidism, exogenous phosphate administration, and extensive cellular injury induce a hyperphosphatemic state. In patients with multiple myeloma, renal insufficiency occurs as a result of hypercalcemia, light chain tubulopathy, urate nephropathy or infection, and hyperphosphatemia usually results from renal failure. We report here a case of a patient with multiple myeloma who had an elevated serum phosphate level measured by the phosphomolybdate UV method without significant renal insufficiency and was finally diagnosed with pseudohyperphosphatemia.

Synchronous, Orthotopic Occurrence of Early Gastric Cancer with Gastrointestinal Stromal Tumor that Mimicked Advanced Gastric Cancer

In recent years, the synchronous occurrence of two adjacent but histologically distinct tumors arising in the same organ has been reported. The simultaneous development of gastric adenocarcinoma and gastrointestinal stromal tumor (GIST) is very uncommon. The question raised was whether such a coexistence is a simple incidental finding or whether the two neighboring tumors are caused by a same unknown carcinogenic agent. Many doctors may have an interest in this rare condition and we expect further studies will be done in order to determine if there is any association between the two different tumors. We report a unique case of a synchronous, orthotopic occurrence of an early gastric cancer with GIST in the same location that mimicked advanced gastric cancer.

Relationship between bronchial anthracofibrosis and endobronchial tuberculosis

BACKGROUND/AIMS: Various pulmonary diseases may be associated with bronchial anthracofibrosis (BAF). Our aim was to identify a relationship between BAF and endobronchial tuberculosis (EBTB). METHODS: In total, 156 patients, diagnosed with EBTB using bronchoscopy, between June 1999 and May 2008, were included. Clinical and bronchoscopic findings between patients with BAF (n = 72, BAF group) and without BAF (n = 84, non-BAF) were analyzed retrospectively. RESULTS: The crude odds ratio (OR) of BAF for EBTB was 8.88 (95% confidence interval, 6.37 to 12.37). On multivariate analysis, adjusting for age, history of biomass smoke exposure, and comorbidities, the most significant independent factor for EBTB was a history of biomass smoke exposure (adjusted OR, 17.471; adjusted p < 0.001). EBTB was more frequent in the right lung, particularly the right middle lobar bronchus, in the BAF group. Actively caseating, edematous-hyperemic, and ulcerative were the major types, with 77 (49%), 33 (21%), and 31 cases (20%), respectively. The BAF group had more ulcerative type, while the non-BAF group had more actively caseating type. The duration of EBTB treatment was similar between the groups. No significant difference was observed in the development of complications during treatment and posttreatment bronchostenosis between the groups. CONCLUSIONS: These findings suggest that BAF may be a risk factor for EBTB and affect the location and morphological type at the time of EBTB development.

A Case of Anaplastic Lymphoma Kinase-Negative Primary Gastric Anaplastic Large Cell Lymphoma / 대한내과학회지

Primary malignant lymphoma of the stomach comprises 1 to 7% of all gastric malignancies and is mostly B-cell type. Anaplastic large cell lymphoma (ALCL) of the stomach is very rare and regarded to have a poor prognosis. A 66-year-old man complained of dyspepsia for 3 days. A esophagogastroduodenoscopic examination revealed a flat, depressed ulcer at the distal antrum. Biopsy of the lesion showed diffuse infiltration of large pleomorphic lymphoid cells that were positive for CD3 and CD30 and negative for cytokeratin and anaplastic lymphoma kinase (ALK). We diagnosed the patient with ALK-negative primary gastric ALCL with multiple lymphadenopathies, and he received systemic chemotherapy. CHOP-like regimens followed by consolidation therapy have been widely used for ALK-negative ALCL. However, the patient maintained complete remission for 36 months with only induction chemotherapy. This case suggests that heavy treatment for ALK-negative ALCL is not required for all patients.

A Case of Brain Death Caused by Salmonella Enterica Serovar Enteritidis Bacteremia / 대한내과학회지

We present a case report of brain death caused by Salmonella enterica serovar Enteritidis bacteremia. A 53-year-old diabetic male was admitted to our hospital with stupor mentality and fever. No evidence of meningitis was found upon cerebrospinal fluid analysis, but diffuse brain edema was shown by magnetic resonance imaging. S. Enteritidis phage type 7 was isolated from blood cultures. We diagnosed the patient with encephalopathy associated with S. Enteritidis bacteremia and treated him by intravenous administration of ceftriaxone and dexamethasone. Fifteen days after admission, the patient was diagnosed with brain death and became a cadaveric donor. Although encephalopathy associated with S. Enteritidis bacteremia is rare, it should be considered as a serious and potentially lethal complication.

A Case of Brain Death Caused by Salmonella Enterica Serovar Enteritidis Bacteremia / 대한내과학회지

We present a case report of brain death caused by Salmonella enterica serovar Enteritidis bacteremia. A 53-year-old diabetic male was admitted to our hospital with stupor mentality and fever. No evidence of meningitis was found upon cerebrospinal fluid analysis, but diffuse brain edema was shown by magnetic resonance imaging. S. Enteritidis phage type 7 was isolated from blood cultures. We diagnosed the patient with encephalopathy associated with S. Enteritidis bacteremia and treated him by intravenous administration of ceftriaxone and dexamethasone. Fifteen days after admission, the patient was diagnosed with brain death and became a cadaveric donor. Although encephalopathy associated with S. Enteritidis bacteremia is rare, it should be considered as a serious and potentially lethal complication.