Retroperitoneal Schwannoma Mimicking an Adrenal Mass / 대한내과학회지

A schwannoma is a benign neoplasm originating from the Schwann cells of the neural sheath. The most common type of benign schwannomas is the acoustic neuroma presenting with deafness. We report a rare case of schwannoma mimicking an adrenal mass. A 66-year-old woman was diagnosed with an adrenal incidentaloma measuring 10 cm in length on a health checkup. The hormonal study revealed that the adrenal mass was non-functioning. Due to a high risk of adrenal malignancy, a retroperitoneal mass excision, distal pancreatectomy, splenectomy, wedge resection of stomach, and left adrenalectomy were conducted. The subsequent histopathologic examination revealed it to be a benign schwannoma.

Population Pharmacokinetic Analysis of Piperacillin/Tazobactam in Korean Patients with Acute Infections / 감염과화학요법

BACKGROUND: For more effective and safer usage of antibiotics, the dosing strategy should be individualized based on the patients’ characteristics, including race. The aim of this study was to investigate the population pharmacokinetic (PK) profiles of piperacillin and tazobactam in Korean patients with acute infections. MATERIALS AND METHODS: At least four consecutive 2/0.25 g or 4/0.5 g doses of piperacillin/tazobactam (TZP) were intravenously infused over 1 h every 8 h for patients with creatinine clearance (CL(cr)) ≤50 ml/min or CL(cr) >50 mL/min, respectively. Blood samples from 33 patients at a steady-state were taken pre-dose and at 0 min, 30 min, and 4-6 h after the fourth infusion. The population PK analysis was conducted using a non-linear mixed-effects method. A likelihood ratio test was used to select significant covariates, with significance levels of P <0.05 for selection and P <0.01 for elimination. RESULTS: Both piperacillin PK and tazobactam PK were well described by a two-compartment model with first-order elimination. Creatinine clearance and body weight, as covariates on clearance (CL) and volume of central compartment (V1), were selected among the covariates possibly affecting PK parameters of both drugs. CL was defined as CL = 2.9 + 4.03 × CL(cr)/47 for piperacillin and CL = 1.76 + 4.81 × CL(cr)/47 for tazobactam. V1 was defined as V1 = 19.5 × weight/60 for piperacillin and V1 = 22.6 × weight/60 for tazobactam. CONCLUSION: The PK profiles of TZP at a steady-state in Korean patients with acute infections were well described by a two-compartment model with first-order elimination. Both piperacillin and tazobactam clearances were significantly influenced by creatinine clearance.

A Case of Polymicrobial Fungal and Bacterial Spondylodiscitis / 대한내과학회지

A 66-year-old female who had undergone surgery for a herniated disc at the L5-S1 level at another hospital 3 months earlier was admitted with persistent back and leg pain. She was diagnosed with spondylodiscitis at the L5-S1 level by magnetic resonance imaging. A biopsy was performed, and Candida parapsilosis and Enterococcus faecium were isolated from the excised material. We report herein a case of successful treatment of polymicrobial spondylodiscitis in accordance with accurate microbiological diagnosis. Based on this case, we hope to encourage physicians to perform biopsies more aggressively or repeatedly to improve the diagnostic yield.

Delta Neutrophil Index as a Prognostic Marker of Early Mortality in Gram Negative Bacteremia / 감염과화학요법

BACKGROUND: Sepsis is a syndrome that results in high morbidity and mortality. We investigated the delta neutrophil index (DN) as a predictive marker of early mortality in patients with gram-negative bacteremia. MATERIALS AND METHODS: We conducted a retrospective study at a tertiary referral hospital in South Korea from November 2010 to March 2011. The DN was measured at onset of bacteremia and 24 hours and 72 hours later. The DN was calculated using an automatic hematology analyzer. Factors associated with 10-day mortality were assessed using logistic regression. RESULTS: A total of 172 patients with gram-negative bacteremia were included in the analysis; of these, 17 patients died within 10 days of bacteremia onset. In multivariate analysis, Sequental organ failure assessment scores (odds ratio [OR]: 2.24, 95% confidence interval [CI]: 1.31 to 3.84; P = 0.003), DN-day 1 > or = 7.6% (OR: 305.18, 95% CI: 1.73 to 53983.52; P = 0.030) and DN-day 3 > or = DN-day 1 (OR: 77.77, 95% CI: 1.90 to 3188.05; P = 0.022) were independent factors associated with early mortality in gram-negative bacteremia. Of four multivariate models developed and tested using various factors, the model using both DN-day 1 > or = 7.6% and DN-day 3 > or = DN-day 1 was most predictive early mortality. CONCLUSIONS: DN may be a useful marker of early mortality in patients with gram-negative bacteremia. We found both DN-day 1 and DN trend to be significantly associated with early mortality.

A Case of Giant Hemangioma of the Liver Presenting with Fever and Cough / 대한내과학회지

Hemangioma of the liver is usually asymptomatic and incidentally discovered. However, giant hemangioma of the liver may be symptomatic, which is an indication for treatment. A 31-year-old female was admitted with a fever and 1-month history of a nonproductive cough. Her blood test results revealed thrombocytopenia, anemia, and mild coagulopathy. A giant hemangioma of the liver was the cause of her symptoms and signs, and was too large for surgical treatment. Therefore, we performed two sessions of transcatheter hepatic arterial embolization (TAE). The patient has been doing well without fever for 1 year following the second TAE procedure. Surgical resection and enucleation are the traditional treatments of choice for symptomatic giant hemangioma of the liver. However, the signs and symptoms of giant hemangioma of the liver improved by TAE in the present case. We herein report a case of complicated giant hemangioma of the liver that was partially treated by TAE and conservative management.

A Case of Skin and Soft Tissue Infection by Mycobacterium massiliense / 대한내과학회지

Mycobacterium massiliense (M. massiliense) was identified recently as a species that separated from M. abscessus. Unlike M. abscessus, M. massiliense responds well to clarithromycin-based antibiotic treatment. Many cases of M. massiliense infections related to iatrogenic procedures have been reported. We report a case of skin and soft tissue infection by M. massiliense, which was not caused by medical appliances, that was treated successfully using clarithromycin monotherapy for -6 months after initial treatment with empirical antibiotics for 4 weeks.

Underestimation of the Calculated Area Under the Concentration-Time Curve Based on Serum Creatinine for Vancomycin Dosing / 감염과화학요법

BACKGROUND: The ratio of the steady-state 24-hour area under the concentration-time curve (ssAUC24) to the MIC (AUC24/MIC) for vancomycin has been recommended as the preferred pharmacodynamic index. The aim of this study was to assess whether the calculated AUC24 (cAUC24) using the creatinine clearance (CLcr) differs from the ssAUC24 based on the individual pharmacokinetic data estimated by a commercial software. MATERIALS AND METHODS: The cAUC24 was compared with the ssAUC24 with respect to age, body mass index, and trough concentration of vancomycin and the results were expressed as median and interquartile ranges. A correlation between the cAUC24 and ssAUC24 and the trough concentration of vancomycin was evaluated. The probability of reaching an AUC24/MIC of 400 or higher was compared between the cAUC24 and ssAUC24 for different MICs of vancomycin and different daily doses by simulation in a subgroup with a trough concentration of 10 mg/L and higher. RESULTS: The cAUC24 was significantly lower than the ssAUC24 (392.38 vs. 418.32 mg.hr/L, P < 0.0001) and correlated weakly with the trough concentration (r = 0.649 vs. r = 0.964). Assuming a MIC of 1.0 mg/L, the probability of reaching the value of 400 or higher was 77.5% for the cAUC24/MIC and 100% for the ssAUC24/MIC in patients with a trough concentration of 10 mg/L and higher. If the MIC increased to 2.0 mg/L, the probability was 57.7% for the cAUC24/MIC and 71.8% for the ssAUC24/MIC at a daily vancomycin dose of 4,000 mg. CONCLUSIONS: The cAUC24 using the calculated CLcr is usually underestimated compared with the ssAUC24 based on individual pharmacokinetic data. Therefore, to obtain a more accurate AUC24, therapeutic monitoring of vancomycin rather than a simple calculation based on the CLcr should be performed, and a more accurate biomarker for renal function is needed.

A Case of Acute Pyelonephritis Caused by Enterococcus Hirae in a Patient with a Horseshoe Kidney / 대한내과학회지

Enterococcus hirae mainly causes infections in animals. It has been rarely encountered in humans and, in most such cases, it is considered to be a contaminant or resident flora. Since the first case of septicemia by E. hirae was reported in 1998, only two cases of acute pyelonephritis (APN) have been reported in Korea. We describe herein a case of APN caused by E. hirae in an 83-year-old man with a horseshoe kidney. Although E. hirae was isolated only from urine and not from the blood, we were able to diagnose it as the causative organism based on the patient's clinical findings, imaging study results, and risk factors including old age, benign prostatic hypertrophy, and a horseshoe kidney.

A Case of Systemic Capillary Leak Syndrome Presenting as Septic Shock / 대한내과학회지

Systemic capillary leak syndrome is a rare disease characterized by life-threatening attacks of reversible plasma extravasation and vascular collapse accompanied by hypotension, hemoconcentration, and hypoalbuminemia. A 36-year-old woman was admitted to this hospital with a fever, along with symptoms consistent with an upper respiratory tract infection and hypotension. Initial laboratory tests revealed several abnormal findings, including an elevated leukocyte count and hematocrit, hypoalbuminemia, and acute renal failure. Here, we report a case of successful treatment of systemic capillary leak syndrome, which can be difficult to distinguish from septic shock.

Serum Cystatin C Is a Major Predictor of Vancomycin Clearance in a Population Pharmacokinetic Analysis of Patients with Normal Serum Creatinine Concentrations

We developed a population pharmacokinetic model of vancomycin by integrating the effects of cystatin C and other demographic factors in a large population of Korean patients with normal serum creatinine concentrations to elucidate the precise role of serum cystatin C concentrations in the prediction of vancomycin clearance. A population pharmacokinetic model of vancomycin was developed using NONMEM software from a total of 1,373 vancomycin concentration measurements in 678 patients whose serum creatinine concentrations were lower than 1.2 mg/dL. Covariate selection revealed that cystatin C was the most influential factor and had negative influence (-0.78) in the relationship. Total body weight, sex, age, and serum creatinine were also significantly correlated with the clearance. The estimated intersubject variabilities of clearance and volume of distribution were 24.7% and 25.1%, respectively. A 14-fold difference in predicted trough concentrations was observed according to only cystatin C concentrations in a population of simulated individuals with median demographic characteristics. The use of serum cystatin C as marker of vancomycin clearance for more accurate predictions of serum vancomycin concentrations could be useful, particularly among patients with normal serum creatinine concentrations.

Serum Retinol-Binding Protein-4 Levels Are Increased in HIV-Infected Subjects with Metabolic Syndrome Receiving Highly Active Antiretroviral Therapy

Metabolic syndrome is an important long term complication in chronic asymptomatic HIV-infected subjects under highly active antiretroviral therapy (HAART), because it can contribute to morbidity and mortality via cardiovascular disease (CVD). Therefore, a predictive marker for early detection of metabolic syndrome may be necessary to prevent CVD in HIV-infected subjects. Retinol-binding protein-4 (RBP-4) has been shown to be associated with metabolic syndrome in various non-HIV-infected populations. We performed a cross-sectional study to evaluate whether serum RBP-4 levels are correlated with metabolic syndrome in HIV-infected subjects receiving HAART. In total, 98 HIV-infected Koreans who had been receiving HAART for at least 6 months were prospectively enrolled. Metabolic syndrome was diagnosed according to the Adult Treatment Panel III criteria, and serum RBP-4 concentrations were measured using human RBP-4 sandwich enzyme-linked immunosorbent assay. Serum RBP-4 levels were significantly higher in HIV-infected subjects receiving HAART with metabolic syndrome (n=33, 33.9+/-7.7 microg/mL) than in those without it (n=65, 29.9+/-7.2 microg/mL) (p=0.012). In multivariate linear regression analysis, the number of components of metabolic syndrome presented and waist circumference were independently, significantly correlated with RBP-4 (p=0.018 and 0.030, respectively). In conclusion, we revealed a strong correlation between RBP-4 and the number of components of metabolic syndrome in HIV-infected subjects receiving HAART.

ERRATUM: Risk Factors and Prognosis for Persistent Candidemia without Catheter Colonization / 감염과화학요법

No abstract available.

The First Case of Abacavir Hypersensitivity Associated with the HLA-B*57:01-Positive Allele in Korea / 감염과화학요법

On the 12th day of abacavir treatment, a 39-year old HIV-infected male patient was admitted with fever, generalized rash, abdominal pain, and watery diarrhea that had persisted for five days. Results of blood tests indicated rapid progression of hepatitis and renal failure. The day after stopping anti-retroviral therapy, his fever subsided and his liver function began to normalize. He was clinically diagnosed with abacavir hypersensitivity and was found to carry the HLA-B*57:01 allele. This is the first reported case of abacavir hypersensitivity associated with the presence of the HLA-B*57:01 allele in Korea.

Clinical Features of Re-Emerging Hepatitis A: An Analysis of Patients Hospitalized during an Urban Epidemic in Korea

From April 2008 to November 2008, many cases of hepatitis A were reported in Seoul and Gyeonggi Province in Korea. Furthermore, the rate of severe or fulminant hepatitis have significantly increased during the latest epidemic (13.4% vs. 5.2%, p=0.044). Therefore, widespread use of vaccine is warranted to reduce the burden of hepatitis A in Korea.

A Case of Libman-Sacks Endocarditis that Developed after Infective Endocarditis / 감염과화학요법

Libman-Sacks endocarditis (LSE) is a valvular heart disease that is associated with autoimmune diseases such as systemic lupus erythematosus and antiphospholipid syndrome (APS). Cases of LSE and APS associated with infection have been reported during the last several years. Herein, we present a patient who was suspected to have developed LSE and catastrophic APS during the treatment of her definite infective endocarditis, which was caused by Staphylococcus aureus, and the patient's condition was complicated with cerebral abscess, sensorineural hearing loss, endophthalmitis, renal infarction, splenic abscess, and septic arthritis.

Risk Factors and Prognosis for Persistent Candidemia without Catheter Colonization / 감염과화학요법

BACKGROUND: Candidemia is one of the most common causes of nosocomial bloodstream infection, and increases the morbidity and mortality rate of seriously ill patients. We evaluated the risk factors and outcomes associated with persistent candidemia without catheter colonization (non-catheter related candidemia) and compared them with those of non-persistent candidemia. MATERIALS AND METHODS: A retrospective case-control study was performed to identify risk factors for, and outcomes of, persistent candidemia. All adults who experienced candidemia in a university-affiliated hospital in Korea between January 2005 and December 2009 were included. Patients with catheter colonization were excluded. Persistent candidemia was defined as the occurrence of candidemia in a patient receiving at least 3 days of systemic antifungal agents prior to the second positive blood culture. RESULTS: Of 605 adult patients with candidemia, 104 (17.2%) patients had persistent candidemia and 23 (3.8%) patients were free of catheter colonization. There were no statistically significant differences in baseline characteristics between patients with persistent and non-persistent candidemia. In univariate analysis, less use of metronidazole, glycopeptide, fluoroquinolone, and aminoglycoside, and presence of Candida parapsilosis were significantly associated with persistent candidemia. In multivariate analysis, less use of metronidazole was an independent factor associated with persistent candidemia. The candidemia related mortality was insignificantly (P=0.094) higher in persistent candidemia than non-persistent candidemia. CONCLUSIONS: Persistent candidemia can occur without catheterization. Patterns of antibiotic use could be associated with the occurrence of persistent candidemia, and prognosis of persistent candidemia seems to be worse than non-persistent candidemia. Further studies for persistent candidemia should be performed.

Cryptococcal Meningitis : 12 Years Experience in a Single Tertiary Health Care Center / 감염과화학요법

BACKGROUND: Cryptococcal infections are frequent in human immunodeficiency virus (HIV)-infected patients. This infection may occur in other immunocompromised patients, and the diagnosis is often delayed in these cases. There are a few reports on cryptococcal meningitis in non-HIV-infected patients in Korea. We reviewed the clinical features and efficacy of antifungal therapy in 33 patients who were treated at a single tertiary health care center of Korea. MATERIALS AND METHODS: The medical records of 33 consecutive patients who were admitted to one tertiary hospital for cryptococcal meningitis between 1995 and 2008 were reviewed retrospectively. Cryptococcal meningitis was confirmed by positive cerebral spinal fluid (CSF) cultures or compatible clinical features plus a positive cryptococcal antigen test of CSF. RESULTS: Of the 33 patients analyzed, 30 cases were non-HIV patients. The outcomes were complete cure in 23 cases, relapse after initial treatment in four cases, and death due to treatment failure in six cases. The main initial manifestations were headache (84.8%), fever (54.5%), and seizure (33.3%). Factors significantly associated with unfavorable outcomes, including mortality and relapse, were afebrile condition, mental change, hearing impairment, initial high opening pressure of CSF (>250 mmH2O), and low initial absolute neutrophil count. On multivariate analysis, afebrile condition was an independent predictor of an unfavorable outcome (odds ratio 17.3; 95% confidence interval 1.0-28.3; P=0.045). CONCLUSIONS: It is necessary to observe closely cryptococcal meningitis patients without fever on admission.

A Case of Meropenem-Resistant Ochrobactrum anthropi Bacteremia / 감염과화학요법

Ochrobactrum anthropi is an oxidase-producing, non-lactose-fermenting, gram-negative bacillus that is frequently isolated from the environment including sinks, baths, soil, and hospital water sources. Recently O. anthropi have been reported as an emerging opportunistic pathogen in immunocompromised patients, particularly in those with indwelling venous catheters. Most O. anthropi were highly resistant to beta-lactam antibiotics except carbapenem. We report a case of O. anthropi bacteremia with an unusual pattern of antibiotic resistance compared to previous reports. A 47-year-old woman undergoing camptobell/cisplatin chemotherapy via indwelling venous catheter (chemoport) for stage IV ovarian cancer, had septicemia due to O. anthropi of unknown origin. The isolates were resistant to all beta-lactams and meropenem and susceptible to aminoglycoside, ciprofloxacin, and trimethoprim-sulfamethoxazole. She recovered from sepsis with combination treatment with imipenem and ciprofloxacin for 3 weeks.

Evaluation of the Effect of Initial dose of Vancomycin using Serum Cystatin C as a Marker in Elderly Patients / 감염과화학요법

BACKGROUND: It has been suggested that the glomerular filtration rate can be predicted on the basis of serum cystatin C concentration. The aim of this study was to investigate the clinical utility of serum cystatin C as a marker of renal function and to evaluate the effect of an initial dose of vancomycin using serum cystatin C concentration in elderly patients. MATERIALS AND METHODS: Data was collected from July 2006 to September 2008. The subjects were elderly patients (> or =60-years-of-age; n=number of patients) who had been treated with vancomycin. Serum concentrations of parameters including vancomycin, creatinine, and cystatin C were measured. Correlations between measured vancomycin concentrations and predicted vancomycin concentrations based on serum cystatin C or serum creatinine were compared, and the initial dose setting of vancomycin on the basis of serum cystatin C concentration was evaluated. RESULTS: Serum cystatin C was a good marker of renal function in comparison with serum creatinine for various doses of vancomycin in the elderly subject. In subpopulation (n=88) with normal serum cystatin C level (< or =1.2 mg/L) who were treated with routine adult vancomycin dose (1g q 12 hours), vancomycin concentration was within the therapeutic range (5-15 mg/L) in 68 patients (77.3%), and was <20 mg/L in 77 of the 88 patients (88.5 %). CONCLUSIONS: Predictive prowess of serum vancomycin concentrations on the basis of the serum cystatin C concentration could be better than that based on the serum creatinine concentration in elderly patients.

A Case of Meropenem-Resistant Ochrobactrum anthropi Bacteremia / 감염과화학요법

Ochrobactrum anthropi is an oxidase-producing, non-lactose-fermenting, gram-negative bacillus that is frequently isolated from the environment including sinks, baths, soil, and hospital water sources. Recently O. anthropi have been reported as an emerging opportunistic pathogen in immunocompromised patients, particularly in those with indwelling venous catheters. Most O. anthropi were highly resistant to beta-lactam antibiotics except carbapenem. We report a case of O. anthropi bacteremia with an unusual pattern of antibiotic resistance compared to previous reports. A 47-year-old woman undergoing camptobell/cisplatin chemotherapy via indwelling venous catheter (chemoport) for stage IV ovarian cancer, had septicemia due to O. anthropi of unknown origin. The isolates were resistant to all beta-lactams and meropenem and susceptible to aminoglycoside, ciprofloxacin, and trimethoprim-sulfamethoxazole. She recovered from sepsis with combination treatment with imipenem and ciprofloxacin for 3 weeks.