Retrobulbar optic neuritis and meningoencephalitis following progressive outer retinal necrosis due to CMV in a patient with AIDS.

We report on a 34-year-old male patient with AIDS who developed retrobulbar optic neuritis and meningoencephalitis following bilateral progressive outer retinal necrosis (PORN) caused by cytomegalovirus (CMV). This case documents the presumed association of PORN with retrobulbar optic neuritis, and CMV meningoencephalitis in an AIDS patient.

Clinical features and outcome of community-onset bloodstream infections caused by extended-spectrum beta-lactamase-producing Escherichia coli.

This study was conducted to evaluate the epidemiology and clinical features of bloodstream infections caused by extended-spectrum beta-lactamase-producing E. coli (ESBL-EC) in community-onset bacteremia. Of 929 episodes of community-onset E. coli bacteremia, 4.1% (38/929) had bacteremia with ESBL producers. Of these, 63.2% (24/38) were further classified as healthcare-associated infections. Although most patients had risk factors for infection due to ESBL producers, three patients with urinary tract infection, four patients with cholangitis, and one patient with a liver abscess had no identified predisposing risk factors. The 30-day mortality was 21.1% (8/38). ESBL-EC is a significant cause of bloodstream infection, even in patients with community-onset infection.

One-year adherence to clinic visits after highly active antiretroviral therapy: a predictor of clinical progress in HIV patients.

OBJECTIVE: To determine whether adherence to clinic visits early after initiation of highly active antiretroviral therapy (HAART) is predictive of long-term clinical outcome. DESIGN: Observational cohort study. SETTING: A tertiary referral hospital. SUBJECTS: A total of 387 adult HIV patients who were followed for at least 1 year after initiation of HAART between January 1998 and December 2004. MAIN OUTCOME MEASUREMENTS: The effect of 1-year adherence to clinic visits on the occurrence of new AIDS-defining illness or death was assessed using Kaplan-Meier survival estimates, and hazard ratios were estimated using Cox proportional hazards regression model. RESULTS: Multivariate analysis revealed that advanced clinical stage, fewer new drugs in HAART, and longer total elapsed time without clinical visits for 1 year after HAART were all significant risk factors for the occurrence of new AIDS-defining illnesses or death. Compared with no missed visits, the hazard ratio adjusted by clinical stage and number of new drugs in HAART was 2.87 (95% confidence interval [CI], 1.34-6.16, P = 0.007) for one missed appointment, 4.37 (95% CI: 1.74-10.98, P = 0.002) for two, and 8.19 (95% CI: 2.95-22.78, P < 0.001) for three or more. CONCLUSION: Adherence to clinic visits early after initiation of HAART is an independent predictor for long-term clinical progression in HIV patients.

The persistence of humoral and cellular immunities more than three decades after smallpox vaccination.

This study assessed the persistence of humoral (neutralising antibody titre to vaccinia virus) and cellular (immediate vaccinia-specific interferon (IFN)-gamma-producing T-cell) immunities to smallpox in a Korean population. Individuals who were vaccinated 25-60 years previously had higher neutralising antibody titres (geometric mean titre (GMT) 13.7; 95% CI 11.0-17.2) than vaccinia-naive individuals (GMT 6.7; 95% CI 5.5-8.0; p <0.001). However, there was no significant difference in cellular immunity between individuals vaccinated previously and vaccinia-naive individuals, and only 15% of the individuals vaccinated previously displayed an immediate IFN-gamma-producing effector-memory response in ELISPOT assays.

Pulmonary tuberculosis in young Korean soldiers: incidence, drug resistance and treatment outcomes.

OBJECTIVE: To determine the incidence and treatment outcomes of pulmonary tuberculosis (PTB) in young soldiers of South Korea. DESIGN: From 2000 to 2004, all soldiers with a new diagnosis of tuberculosis (TB) were enrolled in the study, based on the official records of the Armed Forces Medical Command. The demographic and clinical data of the cases were evaluated retrospectively. RESULTS: A total of 3115 TB cases were reported during the study period, of whom 2071 (66.5%) were reported as PTB. The annual incidence rates of PTB were 96.4 per 100,000 population in 2000, 89.3 in 2001, 67.6 in 2002, 60.2 in 2003, and 63.1 in 2004. A total of 270 patients diagnosed and treated at the Armed Forces Capital Hospital were analysed. Of the Mycobacterium tuberculosis isolates, 87.4% were susceptible to all available anti-tuberculosis drugs; 253 (93.7%) patients eventually completed initial anti-tuberculosis treatment. Among the patients with smear-positive PTB, the cure rate was 89.3% (100/112). CONCLUSION: Our results demonstrate that the incidence of PTB in Korean soldiers, although still high, was declining steadily. With good case management, the overall success rate of initial treatment was approximately 90%.

Outcome of inappropriate empirical antibiotic therapy in patients with Staphylococcus aureus bacteraemia: analytical strategy using propensity scores.

Patients with Staphylococcus aureus bacteraemia (SAB) who received either inappropriate or appropriate empirical therapy were compared by using two risk stratification models: (1) a cohort study using a propensity score to adjust for confounding by empirical treatment assignment; and (2) a propensity-matched case-control study. Inappropriate empirical therapy was modelled on the basis of patient characteristics, and included in the multivariate model to adjust for confounding. For case-matching analysis, patients with inappropriate empirical therapy (cases) were matched to those with appropriate empirical therapy (controls) on the basis of the propensity score (within 0.03 on a scale of 0-1). In total, 238 patients with SAB were enrolled in the cohort study. Characteristics associated with inappropriate empirical therapy were methicillin resistance, underlying haematological malignancy, no history of colonisation with methicillin-resistant S. aureus, and a long hospital stay before SAB. These variables were included in the propensity score, which had an area under the receiver operating characteristics curve of 85%. In the cohort study, SAB-related mortality was 39% (45/117) for inappropriate empirical therapy vs. 28% (34/121) for appropriate empirical therapy (odds ratio (OR) 1.60; 95% CI 0.93-2.76). After adjustment for independent predictors for mortality and the propensity score, inappropriate empirical therapy was not associated with mortality (adjusted OR 1.39; 95% CI 0.62-3.15). In the matched case-control study (50 pairs), SAB-related mortality was 32% (16/50) for inappropriate empirical therapy and 28% (14/50) for appropriate empirical therapy (McNemar's test; p 0.85; OR 1.15; 95% CI 0.51-2.64). In conclusion, inappropriate empirical therapy resulted in only a slight tendency towards increased mortality in patients with SAB.

Epidemiological characteristics of occupational blood exposures of healthcare workers in a university hospital in South Korea for 10 years.

This study investigated the epidemiological characteristics of occupational blood exposures (OBEs) of healthcare workers (HCWs) in South Korea, and examined trends of OBEs after implementing blood exposure prevention (BEP) programmes. The study was conducted between 1 January 1992 and 31 December 2001 at a university-affiliated acute care hospital in Seoul. The BEP programmes comprised in-service education, hepatitis B virus (HBV) vaccination, and postexposure evaluation and prophylaxis. From 959 reported cases of OBEs, the crude incidence density (ID) was 2.62 cases per 100 person-years. The major risk groups for OBEs were physicians (ID 4.34) and new employees. The major type of OBE was from sharps injuries, including needlesticks (94.0%). OBE cases occurred more frequently during the spring (36.4%). The frequency of the serological tests of anti-hepatitis B surface antigen of HCWs changed significantly each year (P<0.05). The major serological risk for source patients was HBV (52.1%), but the risks for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) increased significantly each year (P<0.05). There were no seroconversion cases following OBEs among the tested HCWs. In summary, we established the epidemiological characteristics of OBEs in a South Korean university hospital, and reduced the risk of OBEs of major risk groups by BEP programmes. We also found an increase in the risk of HCV and HIV during the study period, suggesting that OBEs could be a serious threat to HCWs.

Clinical features and outcome of patients with community-acquired Pseudomonas aeruginosa bacteraemia.

Cases of community-acquired Pseudomonas aeruginosa bacteraemia (n = 39) that occurred at a tertiary-care hospital during a 5-year period were analysed retrospectively. The commonest underlying diseases were solid tumour (41%) and haematological malignancy (18%). Most (44%) of the patients were neutropenic, and 39% had septic shock at initial presentation. The 30-day attributable mortality rate was 39%. Two previously healthy patients were identified with fatal P. aeruginosa pneumonia with bacteraemia. P. aeruginosa bacteraemia is a fatal infection that should be considered in the differential diagnosis of patients presenting from the community with rapidly progressive sepsis.

Enhanced neutrophil functions by recombinant human granulocyte colony-stimulating factor in diabetic patients with foot infections in vitro.

This study was performed to evaluate the effect of granulocyte-colony stimulating factor on neutrophil functions in diabetic patients with active foot infections in vitro. Twelve diabetic patients with foot infections and 12 normal volunteers were enrolled. Neutrophils from peripheral blood were incubated with granulocyte colony-stimulating factor (G-CSF, 50 ng/mL) for 20 min. Superoxide production of neutrophils was measured by the reduction of ferricytochrome C. Neutrophil phagocytosis was assayed using Staphylococcus aureus and the weighted phagocytic index was calculated. Superoxide production of neutrophils in diabetic patients with foot infections was 7.7 (unit: nmol/2 x 10(5) cells/60 min), which was significantly lower than that in controls (12.0) (p<0.05). G-CSF increased neutrophil superoxide production to 12.1 in diabetic patients with foot infections and to 19.8 in controls (p<0.05 for each). Weighted phagocytic index in diabetic patients with foot infections was 0.77, which was not significantly different from that of the controls (0.69). Weighted phagocytic index was increased significantly by G-CSF to 0.88 in diabetic patients with foot infections and to 0.79 in controls (p<0.05 for each). In conclusion, G-CSF significantly enhanced neutrophil functions in diabetic patients with foot infections in vitro.

A case of disseminated Cryptococcosis with skin eruption in a patient with acute leukemia.

Disseminated cryptococcosis is a life-threatening infection caused by Cryptococcus neoformans and cutaneous dissemination occurs in 10-15% of patients. We report a case of a 49-y-old leukemic patient with disseminated cryptococcosis who presented with fever, headache, normal cerebrospinal fluid profile and multiple skin lesions mimicking molluscum contagiosum.

Carbapenem resistance mechanisms in Pseudomonas aeruginosa clinical isolates.

In order to define the contributions of the mechanisms for carbapenem resistance in clinical strains of Pseudomonas aeruginosa, we investigated the presence of OprD, the expressions of the MexAB-OprM and MexEF-OprN systems, and the production of the beta-lactamases for 44 clinical strains. All of the carbapenem-resistant isolates showed the loss of or decreased levels of OprD. Three strains overexpressed the MexAB-OprM efflux system by carrying mutations in mexR. These three strains had the amino acid substitution in MexR protein, Arg (CGG) --> Gln (CAG), at the position of amino acid 70. None of the isolates, however, expressed the MexEF-OprN efflux system. For the characterization of beta-lactamases, at least 13 isolates were the depressed mutants, and 12 strains produced secondary beta-lactamases. Based on the above resistance mechanisms, the MICs of carbapenem for the isolates were analyzed. The MICs of carbapenem were mostly determined by the expression of OprD. The MICs of meropenem were two- to four-fold increased for the isolates which overexpressed MexAB-OprM in the background of OprD loss. However, the elevated MICs of meropenem for some individual isolates could not be explained. These findings suggested that other resistance mechanisms would play a role in meropenem resistance in clinical isolates of P. aeruginosa.

Multicenter surveillance study for nosocomial infections in major hospitals in Korea. Nosocomial Infection Surveillance Committee of the Korean Society for Nosocomial Infection Control.

BACKGROUND: The goals of a surveillance for nosocomial infections (NIs) are to observe the magnitude and characteristics of NIs and to plan and evaluate policies and guidelines of infection control. This study was designed to determine the rate and distribution of NIs and their causative pathogens in Korean hospitals. METHODS: Prospective surveillance was performed at 15 acute care hospitals with more than 500 beds during a 3-month period from June to August 1996. The case-finding methods were laboratory-based surveillance for patients in the general wards and a direct review of medical charts done regularly for all the patients in the intensive care units. RESULTS: A total of 3162 NIs were found among 85,547 discharged patients, with an overall nosocomial infection rate of 3.70 per 100 patients discharged. Urinary tract infections constituted 30.3% of all NIs. Other infections were pneumonias, 17.2%, surgical site infections, 15.5%, and primary bloodstream infections, 14.5%. The infection rate was the highest in neurosurgery (14.21), followed by neurology (8. 62) and ontology services (6.70). The infection rate in intensive care units was higher than it was in the general wards (10.74 vs 2. 57, P =.001). The commonly isolated organisms were Staphylococcus aureus (17.2%), Pseudomonas aeruginosa (13.8%), and Escherichia coli (12.3%). CONCLUSIONS: This first multicenter surveillance study provided extensive information on the current status and trends of NIs in major hospitals in Korea. The results may contribute to the evaluation of infection control programs and the development of effective strategies in these hospitals.

Apoptotic chondrocyte death in human osteoarthritis.

OBJECTIVE: To define apoptotic chondrocyte death and the expression of Bcl-2, Bax, and Fas in human osteoarthritis (OA) cartilage. METHODS: Cartilage samples were obtained from patients with knee OA at the time of joint replacement surgery and from normal autopsy cases. In OA, sections were obtained both from the lesional area, usually within 1 cm of bony exposure, and from the non-lesional area, which had macroscopically normal appearance or only mild surface irregularities. Apoptosis was verified by microscopic examination of hematoxylin and eosin stained specimens, TUNEL staining, electron microscopy, and DNA ladder analysis by electrophoresis. Immunohistochemistry was done to study the expression of Bcl-2, Bax, and Fas. Apoptotic cells and Bcl-2, Bax, and Fas positive cells were counted within defined microscopic fields. Expression of Bcl-2 and Bax was verified by Western blot. RESULTS: The percentage of apoptotic cells in the lesional area was significantly higher than in the non-lesional area in cartilage from the same patient with OA, while apoptotic cells were rarely seen in normal cartilage. This result was confirmed by TUNEL stain. Many chondrocytes with chromatin condensation were verified in electron microscopy, and DNA from OA lesional cartilage revealed a DNA ladder on electrophoresis. Bcl-2 and Fas expressions were significantly higher in the OA lesional area than in the non-lesional area. On the other hand, Bcl-2 expression in normal cartilage was significantly higher than in OA cartilage. There was no significant difference in Bax expression among normal, OA lesional, and OA non-lesional cartilage. CONCLUSION: These results show that apoptotic chondrocyte death occurs more frequently in OA compared to normal cartilage and in OA lesional compared to OA non-lesional cartilage. The different expression patterns of Bcl-2 and Fas in OA lesional and non-lesional cartilage suggest that they might be involved in the pathogenesis of OA.

Survey of extended-spectrum beta-lactamases in clinical isolates of Escherichia coli and Klebsiella pneumoniae: prevalence of TEM-52 in Korea.

Two hundred ninety isolates of Escherichia coli were investigated for the production of extended-spectrum beta-lactamases (ESBLs). Fourteen (4.8%) of the 290 strains were found to produce ESBLs. Each of the 14 strains produced one or two ESBLs, as follows: 10 strains produced TEM-52, 1 strain produced SHV-2a, 1 strain produced SHV-12, 1 strain produced a CMY-1-like enzyme, and 1 strain expressed SHV-2a and a CMY-1-like enzyme. Another two strains for which the MICs of ceftazidime and cefoxitin were high, were probable AmpC enzyme hyperproducers. Because of the high prevalence of TEM-52 in E. coli isolates, we further investigated the TEM-type ESBLs produced by Klebsiella pneumoniae in order to observe the distribution of TEM-52 enzymes among Enterobacteriaceae in Korea. All TEM enzymes produced by 12 strains of K. pneumoniae were identified as TEM-52. To evaluate the genetic relatedness among the organisms, ribotyping of TEM-52-producing E. coli and K. pneumoniae was performed. The ribotyping profiles of the organisms showed similar but clearly different patterns. In conclusion, TEM-52 is the most prevalent TEM-type ESBL in Korea.

Mycobacterium tuberculosis infection in a corticosteroid-treated rheumatic disease patient population.

OBJECTIVE: To investigate the incidence and risk factors of Mycobacterium tuberculosis infection in longterm corticosteroid treated rheumatic disease patients. METHODS: We assessed retrospectively the incidence of active tuberculosis and its risk factors in 269 rheumatic disease patients treated with moderate to high doses of corticosteroid for an evaluation period representing 1,035 corticosteroid years of therapy. RESULTS: The mean daily dose of steroid was 18.7 mg prednisolone and the mean daily dose during the first year of treatment was 20.4 mg prednisolone. 21 of these patients developed active tuberculosis resulting in an incidence rate of 20/1,000 patient-years. Cumulative and mean daily steroid doses during the follow-up period and during the first year of treatment, and a history of steroid pulse therapy were significantly correlated with the development of tuberculosis. A past history of tuberculosis, initial chest P-A abnormality, the starting dose of steroid, a history of more than 30 mg/day of prednisolone for more than one month, and a history of cytotoxic therapy were not related to the development of tuberculosis. CONCLUSION: The incidence of active tuberculosis is increased in rheumatic patients on moderate-to-high dose steroid treatment. Its risk factors are the cumulative and mean daily steroid doses during the follow-up period and during the first year of steroid treatment, and a history of steroid pulse therapy.

Epidemiological typing of methicillin-resistant Staphylococcus aureus outbreak isolates by pulsed-field gel electrophoresis and antibiogram.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens. In April 1997, there were five MRSA-infected patients among 16 patients in the Neonatal Intensive Care Unit (NICU), Seoul National University Hospital, which is a tertiary-care hospital with 1,500 beds. The infections had spread from twin patients with MRSA who had transferred from Hospital C. MRSA was isolated from the axilla of 15 (94%) of the 16 patients, including the two patients with obvious infections. Three (19%) of 16 doctors and nine (30%) of 30 nurses had MRSA colonization of the anterior nares. Six different PFGE patterns (A through F) were identified in the 53 isolates of MRSA tested. Twelve of 13 isolates from infected sites of five patients showed pattern F. Three MRSA strains obtained from hospital C showed closely or possibly related pattern F. MRSA of type F was isolated from three of 16 patients' axilla, and one of 3 doctors' and three of 30 nurses' nasal swabs. The antibiogram code for 12 of 13 MRSA isolates from five infected patients was 66,754. PFGE patterns of these isolates were either F, F1, F2 or Fa. Only one of three strains isolated from clinical specimens of patients in Hospital C showed the antibiogram code 66754, although they were all PFGE types F1 and Fa. In conclusion, the presumptive sources of the outbreak of MRSA infection in NICU were the twin patients transferred from hospital C. Antibiogram correlated reasonably well to the PFGE type. An effective notification system is needed when a MRSA-infected patient is transferred to another hospital to control the spread of the infection.

Central nervous system involvement in patients with scrub typhus.

Scrub typhus, which is caused by Orientia tsutsugamushi, is a systemic illness that causes generalized vasculitis. The central nervous system (CNS) is the most crucial target in other rickettsial diseases; however, there have been several reports of encephalitis or meningitis without direct evidence of rickettsial invasion of the CNS in cases of scrub typhus. To investigate CNS involvement in cases of scrub typhus, we analyzed the CSF profiles (cell count and levels of protein and glucose) and amplified rickettsial DNA in CSF specimens by means of nested polymerase chain reaction (PCR) for 25 patients with the infection. Mild pleocytosis was present in 48% of the patients: CSF white blood cell counts ranged from 0 to 110/mm3 (mean [+/- SD] count, 16.3 +/- 27.0/mm3), and the mean (+/- SD) lymphocyte proportion was 51.9% +/- 23.9%. The CSF protein level was increased (>50 mg/dL) in seven patients. Nested PCR amplified six products from the 25 CSF specimens: four of the products were Boryong genotypes, and two were Karp genotypes. The results of this study suggest that O. tsutsugamushi does invade the CSF and that scrub typhus should be considered one of the causes of mononuclear meningitis in areas of endemicity.

A case of laboratory-acquired murine typhus.

We encountered a 32-year-old Korean woman who developed murine typhus in a laboratory. She worked as a technician in a laboratory for rickettsial disease. Immunofluorescence test with rickettsial antigen (R. typhi) was positive at 1: 320 on admission and 1: 1280 after 4 weeks. A dose of 200 mg of doxycycline for 7 days proved to be effective for her condition.

Acquired immune deficiency syndrome--report of an autopsy case.

Authors report the first autopsy case of acquired immune deficiency syndrome in Korea. The patient was a 26 years old Korean male who died of respiratory failure due to mixed pulmonary infections. He had history of homosexual contacts with partners of both domestic and foreign nationalities. Initial presentation was unexplained fever for two months. Serological test and western blot test for anti-HIV were positive and T-cell subset analysis revealed T3/T4/T8 to be 73/8/67%. Pulmonary tuberculosis with mediastinal lymphadenopathy and esophagonadal fistula and oral candidiasis were presented. Respiratory infection progressed gradually and he died seven months after the initial symptom. Autopsy findings were generalized severe lymphoid cell depletion, especially of T-cell population and mixed pulmonary infections with Pneumocystis carinii and cytomegalovirus (CMV). The CMV infection involved lungs and adrenals. Oral candidiasis was also demonstrated.