Management of newborns and healthcare workers exposed to isoniazid-resistant congenital tuberculosis in the neonatal intensive care unit.

BACKGROUND: Management of newborns and healthcare workers (HCWs) exposed to congenital tuberculosis (TB) in the neonatal intensive care unit (NICU) has been reported rarely. AIM: To outline a contact investigation process for individuals exposed to congenital TB in the NICU and investigate nosocomial transmission. Additionally, to assess the efficacy and safety of window prophylaxis in exposed newborns. METHODS: A baby, born at a gestational age of 28 + 1 weeks, was diagnosed with isoniazid-resistant congenital TB on the 39th day of admission to the level IV NICU. Newborns and HCWs exposed cumulatively for ≥8 h underwent contact investigation and follow-up for a year. FINDINGS: Eighty-two newborns underwent contact investigation. All newborns displayed normal chest X-rays, and 42 hospitalized newborns tested negative for acid-fast bacilli stain and Xpert® MTB/RIF assay in their endotracheal sputum or gastric juices. Eighty received window prophylaxis: six of 75 on rifampin experienced mild adverse events, and none of the five on levofloxacin. After 12 weeks, five (6.1%) had a positive tuberculin skin test, all of whom had already received the Bacillus Calmette-Guérin vaccine and tested negative on TB interferon-gamma releasing assay. Of 119 exposed HCWs, three (2.5%) were diagnosed with latent TB infection and completed a four-month rifampin therapy. There was no active TB disease among exposed newborns and HCWs during a one-year follow-up. CONCLUSION: Timely diagnosis of congenital TB is crucial for minimizing transmission among exposed neonates and HCWs in the NICU setting. In cases of isoniazid-resistant index patients, even premature newborns may consider the use of rifampin or levofloxacin for window prophylaxis.

Melanoma of the Sinonasal Tract: Value of a Septate Pattern on Precontrast T1-Weighted MR Imaging.

BACKGROUND AND PURPOSE: Various tumors of the sinonasal tract can exhibit high signal intensity on T1WI. The purpose of this study was to determine the value of a septate pattern on precontrast T1WI for diagnosing sinonasal melanoma. MATERIALS AND METHODS: Retrospectively, 3 observers independently reviewed MR images of 31 histologically proved sinonasal melanomas with special attention to the presence or absence of a septate pattern on precontrast T1WI, defined as alternating hyperintense and hypointense striations on precontrast T1WI. For comparison, we evaluated the prevalence of a septate pattern on precontrast T1WI in 106 nonmelanomatous sinonasal malignant tumors with 16 different histologic types. We also tried to identify the histopathologic features responsible for the septate pattern on precontrast T1WI. RESULTS: Twenty-seven (87.1%) of 31 sinonasal melanomas showed hyperintense foci on T1WI, among which a septate pattern on precontrast T1WI was seen in 23 (74.2%), while 22 (20.8%) of 106 nonmelanomatous malignant tumors demonstrated hyperintense foci on T1WI, among which only 3 (2.8%) showed a septate pattern on precontrast T1WI. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of a septate pattern on precontrast T1WI for the diagnosis of sinonasal melanoma were 74%, 97%, 88%, 93%, and 92%, respectively. Although limited due to the retrospective nature, 4 of 23 histologically reviewed sinonasal melanomas revealed an uneven distribution of melanin with alternating melanin and fibrous bands within the tumors. CONCLUSIONS: A septate pattern on precontrast T1WI might be an adjunctive imaging finding for the diagnosis of sinonasal melanoma. This might be attributed histologically to an uneven distribution of melanin and hemorrhage within the tumors.

Infection Status with Plerocercoid of Ligulid Tapeworm in Cyprinid Fish from Three Lakes in Republic of Korea.

We have investigated freshwater cyprinid fish for its current infection status with plerocercoid of ligulid tapeworm in the Republic of Korea. A total of 6,049 (517 Euiam Lake and 4,071 Hoengseong Lake in Gangweon-do and 1,461 Chungju Lake in Chungcheongbuk-do) fish were examined by dissecting the peritonial cavity between March 2015 and December 2016. Totally 45 (0.74 %) fish in of 5 (26.3 %) species (8 Squalidus japonicus coreanus, 6 Squalidus gracilis majimae, 7 Opsariichthys uncirostris amurensis, 15 Zacco platypus and 9 Erythroculter erythropterus) were infected with plerocercoids of ligulid tapeworm. The infection density with plerocercoids in Erythroculter erythropterus was 12 - 26 per fish infected in Erythroculter erythropterus, and 1 - 2 in other 4 fish species. The plerocercoid was ivory-white and 26.2 - 57.8 cm long. The prevalence value in this survey was 0.9 % (45/6,049). The genetic analysis in this study was conducted to identify plerocercoid species. Based on genetic analysis with data in GenBank, these plerocercoids were identified as the L. intestinalis.

Differentiation of Hemangioblastoma from Metastatic Brain Tumor using Dynamic Contrast-enhanced MR Imaging.

PURPOSE: The aim of this study was to differentiate hemangioblastomas from metastatic brain tumors using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and compare the diagnostic performances with diffusion-weighted imaging (DWI) and dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI). METHODS: We retrospectively reviewed 7 patients with hemangioblastoma and 15 patients with metastatic adenocarcinoma with magnetic resonance imaging (MRI) including DWI, DSC-MRI, and DCE-MRI. Apparent diffusion coefficient (ADC), relative cerebral blood volume (rCBV), and DCE-MRI parameters (K trans, k ep, v e, and v p) were compared between the two groups. The diagnostic performance of each parameter was evaluated with receiver operating characteristic (ROC) curve analysis. RESULTS: v p, k ep, and rCBV were significantly different between patients with hemangioblastoma and those with metastatic brain tumor (p < 0.001, p = 0.005, and p = 0.017, respectively). A v p cutoff value of 0.012 and a rCBV cutoff value of 8.0 showed the highest accuracy for differentiating hemangioblastoma from metastasis. The area under the ROC curve for v p and rCBV was 0.99 and 0.89, respectively. A v p > 0.012 showed 100 % sensitivity, 93.3 % specificity, and 95.5 % accuracy and a rCBV > 8.0 showed 85.7 % sensitivity, 93.3 % specificity, and 90.9 % accuracy for differentiating hemangioblastoma from metastatic brain tumor. CONCLUSION: DCE-MRI was useful for differentiating hemangioblastoma from metastatic brain tumor.

Family history of diabetes and the risk of subclinical atherosclerosis.

AIM: This study investigated the influence of a family history of diabetes on the risk of subclinical coronary atherosclerosis according to coronary computed tomography angiography (CCTA) in asymptomatic individuals. METHODS: A total of 6434 consecutive asymptomatic individuals with no prior history of coronary artery disease voluntarily underwent CCTA evaluation as part of a general health examination. Coronary atherosclerotic plaque and significant coronary artery stenosis (degree of stenosis ≥50%) on CCTA were assessed. Logistic regression analysis was used to determine the association between a family history of diabetes and atherosclerotic plaque or significant coronary artery stenosis according to the degree of diabetes (normal, prediabetic and diabetic). RESULTS: Mean age of study participants was 53.7±7.6 years, and 4694 (73.0%) were male. A total of 1593 (24.8%) participants had a family history of diabetes in a first-degree relative. Among the study participants, 1115 (17.3%), 3122 (48.5%) and 2197 (34.1%) were categorized as diabetic, prediabetic and normal, respectively. In diabetic participants, after stepwise adjustments for clinical and laboratory variables, a family history of diabetes was significantly associated with non-calcified plaque (P<0.05 for all), but did not appear to be associated with either calcified or mixed plaques or with significant coronary artery stenosis (P>0.05 for all). In prediabetic and normal participants, a family history of diabetes was not associated with either atherosclerotic plaque or significant coronary artery stenosis (P>0.05 for all). CONCLUSION: In asymptomatic diabetic individuals, a family history of diabetes is consistently associated with non-calcified coronary plaque after adjusting for risk factors.

Higher serum uric acid as a protective factor against incident osteoporotic fractures in Korean men: a longitudinal study using the National Claim Registry.

UNLABELLED: In this large longitudinal study of 16,078 Korean men aged 50 years or older, we observed that baseline elevation of serum uric acid level significantly associated with a lower risk of incident fractures at osteoporosis-related sites during an average follow-up period of 3 years. INTRODUCTION: Male osteoporosis and related fractures are becoming recognized as important public health concerns. Oxidative stress has detrimental effects on bone metabolism, and serum uric acid (UA) is known to be a strong endogenous antioxidant. In the present study, we performed a large longitudinal study with an average follow-up period of 3 years to clarify the role of UA on the risk of incident osteoporotic fractures (OFs). METHODS: A total of 16,078 Korean men aged 50 years or older who had undergone comprehensive routine health examinations were enrolled. Incident fractures at osteoporosis-related sites (e.g., hip, spine, distal radius, and proximal humerus) that occurred after the baseline examinations were identified from the nationwide claims database of the Health Insurance Review and Assessment Service of Korea by using selected International Classification of Diseases, 10th revision codes. RESULTS: In total, 158 (1.0 %) men developed incident OFs. The event rate was 33.1 per 10,000 person-years. Subjects without incident OFs had 6.0 % higher serum UA levels than subjects with OFs (P = 0.001). Multivariable-adjusted Cox proportional hazard analyses adjusted for age, body mass index, glomerular filtration rate, lifestyle factors, medical and drug histories, and the presence of baseline radiological vertebral fractures revealed that the hazard ratio per standard deviation increase of baseline UA levels for the development of incident OFs was 0.829 (95 % CI = 0.695-0.989, P = 0.038). CONCLUSIONS: These data provide the epidemiological evidence that serum UA may act as a protective factor against the development of incident OFs in Korean men.

Paradoxical response in HIV-negative patients with pleural tuberculosis: a retrospective multicentre study.

OBJECTIVE: To evaluate the incidence, clinical characteristics and predicting factors for the development of paradoxical response in human immunodeficiency virus negative patients with isolated pleural tuberculosis (TB). DESIGN: A multicentre, retrospective cohort study including 458 patients who were diagnosed and treated with isolated pleural TB between March 2005 and February 2010. RESULTS: Paradoxical response developed in 72 patients (16%) with isolated pleural TB. The mean time to development of paradoxical response was 8.8 ± 6.4 weeks after initiation of anti-tuberculosis treatment. The main presentation of paradoxical response was aggravation of pre-existing pleural effusion in 58 patients (81%). However, the majority of the patients who developed paradoxical response had no associated symptoms (n = 49, 68%). In multiple logistic regression analysis, development of paradoxical response was independently associated with the proportion of eosinophils (adjusted OR 1.293, 95%CI 1.077-1.553) and protein concentrations (adjusted OR 0.590, 95%CI 0.397-0.878) in the pleural fluid at the time of diagnosis. CONCLUSION: Paradoxical response developed in 16% of the patients approximately 2 months after initiation of anti-tuberculosis treatment, presenting with aggravation of pre-existing pleural effusion. Development of paradoxical response was associated with the proportion of eosinophils and protein concentrations in the pleural fluid at the time of diagnosis.

Host specificity of Pisidium coreanum (Bivalvia: Sphaeriidae) to larval infection with a human intestinal fluke Echinostoma cinetorchis (Trematoda: Echinostomatidae) in Korea.

The fingernail clam, Pisidium coreanum, has been traditionally consumed raw as a so-called drug therapy by patients with bone fractures in Korea. The present study was designed to determine the possible occurrence and, if present, the prevalence of Echinostoma cinetorchis in P. coreanum collected at a local site, and to determine the susceptibility of the clams in the laboratory to infection with miracidia and cercariae of E. cinetorchis. No cercariae or metacercariae of E. cinetorchis were observed in field-collected P. coreanum clams. In susceptibility experiments with laboratory-reared clams, individuals exposed to miracidia of E. cinetorchis did not release cercariae by 20 days after exposure; necropsy of exposed clams failed to show development of any sporocysts or rediae. To confirm the possibility of these clams serving as an experimental second intermediate host of E. cinetorchis, 20 of them were exposed to E. cinetorchis cercariae from experimentally infected Segmentina hemisphaerula that had been previously exposed to miracidia of E. cinetorchis; all exposed clams became infected. Metacercariae from clams at 14 days postinfection were fed to rats, and adult worms were recovered from the ileocecal regions. This is the first report of P. coreanum serving as second intermediate host of E. cinetorchis.

Occurrence of a diploid type and a new first intermediate host of a human lung fluke, Paragonimus westermani, in Korea.

The biology, chromosome number, and karyotype of a lung fluke, Paragonimus westermani (Kerbert, 1878) collected in Haenam, Haenam-gun Chollanam-do, Korea were analyzed. We compared the size of metacercariae from Haenam with those taken from a crayfish collected at Youngam, Youngam-gun, Chollanam-do, Korea. The mean length of P. westermani metacercariae from Haenam was 300.3 microm and that from Youngam was 362.0 microm. Adult worms were recovered from the lungs of experimentally infected dogs. The mean egg sizes obtained from adult flukes were 72.1 x 46.8 microm from Haenam and 93.5 x 54.2 microm from Youngam. Semisulcospira tegulata collected in the Youngam area were found to be infected with cercariae of P. westermani, one of the snail-borne human lung fluke trematodes in Korea. Of 4218 snails studied, 5 (0.12%) harbored P. westrermani larvae. This is the first report of S. tegulata serving as the initial intermediate host of P. westermani. The chromosome numbers of P. westermani from Haenam and Youngam were 2n = 22 and 3n = 33. The diploid type of P. westermani has not been previously reported in Korea.

Geographical variation of the liver fluke, Clonorchis sinensis, from Korea and China based on the karyotypes, zymodeme and DNA sequences.

Genetic characterization was carried out in order to reveal the geographical variations of the oriental liver fluke, Clonorchis sinensis (Trematoda: Opisthorchiidae), collected in Korea and China. The chromosome number was 2n=56 in both Korean (Kimhae) and Chinese (Liaoning) flukes, and chromosomes were divided into two groups based on their sizes; consisting of 8 pairs of large and 20 pairs of small chromosomes. However, the karyotypes showed some differences between Korean and Chinese flukes. Isozyme analysis showed that two loci from each enzyme of aconitase and esterase (alpha-Na and beta-Na); only one locus each from six enzymes, glucose-6-phosphate dehydrogenase (G6PD), alpha-glycerophosphate dehydrogenase (GPD), 3-hydroxybutyrate dehydrogenase (HBDH), malate dehydrogenase (MDH), phosphoglucose isomerase (PGl) and phosphoglucomutase (PGM). Most of loci in two populations of C. sinensis showed homozygous monomorphic banding patterns and one of them, GPD was specific as genetic markers between two different populations. Two populations were very closely clustered within the range of genetic identity value of 0.998-1.0. We also compared patterns of intraspecific polymorphism of two markers with contrasted modes of evolution, nuclear ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA) of the liver fluke from Kimhae, Guangxi and Liaoning. They showed a high homology. In conclusion, three populations of C. sinensis from Korea and China showed high homogeneity in the nucleotide sequences of the 18S rDNA, ITS2 and mtCOI gene.

Localization of a major allergen, Der p 2, in the gut and faecal pellets of Dermatophagoides pteronyssinus.

BACKGROUND: The house dust mite Dermatophagoides ptronyssinus is one of the most significant indoor sensitizing agents of allergy. Allergen localization may indicate the importance of secreted materials, faeces, and nonexcreted mite body components as allergen sources. OBJECTIVE: This study attempted to localize the sites and concentrations of Der p 2 in the cryostat sections of D. pteronyssinus using antirecombinant Der p 2 monoclonal antibody. METHODS: Male and female mites and mite faeces collected separately from both sexes were used. Live mites were embedded and serial cryostat sections for light microscopy were performed. Anti-recombinant Der p 2 monoclonal antibody previously produced by the authors was used. For immunoprobing, mite cryostat sections were incubated in the following antibody-containing solutions: monoclonal antibody against Der p 2 was initially applied to the sections and fluorescent isothiocyanate conjugated antimouse immunoglobulin G was reacted as the secondary antibody. The faecal pellets were treated the same as described above. RESULTS: Immunofluorescent probing of cryostat sections with the monoclonal antibody showed labelling of the gut lining, gut contents and defecated faecal pellets. No other internal organs were identified as positively labelled. CONCLUSION: This study suggested that a major allergen, Der p 2, found in the house dust mite D. pteronyssinus is derived from the digestive tract and concentrated in the faeces.

Intestinal parasite infections at an institution for the handicapped in Korea.

Stool and cellotape anal swab examinations were carried out in August 1997 on handicapped people at an institution located in Chorwon-gun, Kangwon-do, Korea. A total of 112 stool samples (78 males and 34 females) revealed three cases of Trichuris trichiura infection and one case of Enterobius vermicularis infection. Other helminth eggs were not detected. The overall prevalence rate was 35.7% (38.5% for males and 29.4% for females). More than two different kinds of parasites were found in 42.0% of the positive stool samples (17 cases). The infection rates for protozoan cysts are as follow: Entamoeba coli (25.0%), E. histolytica (1.8%), Endolimax nana (21.4%), Iodoamoeba bütschlii (1.8%) and Giardia lamblia (0.9%). In cellotape anal swab examinations (165 samples), the prevalence rate of E. vermicularis was 20.6% (25.7% of males and 9.6% of females). In conclusion, the handicapped people in the institution showed higher infection rates of protozoan parasites and E. vermicularis, possibly due to more accessibility to the infection.

Chromosomes of the liver fluke, Clonorchis sinensis.

A karyological study was carried out in order to compared the chromosome numbers, chromosome morphologies and karyotypes of the oriental liver fluke, Clonorchis sinensis (Trematoda: Opisthorchiidae), collected from Korea and China. Chromosome preparations were made by means of air-drying method. The chromosome number was 2n = 56 in both Korean and Chinese flukes, and chromosomes were divided into two groups based on this size; consisting of 8 pairs of large and 20 pairs of small chromosomes. However, the karyotypes showed some differences between Korean and Chinese flukes. The karyotype of liver flukes from Korea consisted of three metacentric pairs, one meta-/submetacentric pair, 16 submetacentric pairs and eight subtelocentric pairs of chromosomes. On the other hand, liver flukes from China consisted of two metacentric pairs, two meta-/submetacentric pairs, 16 submetacentric pairs and eight subtelocentric pairs of chromosomes.

The first Korean case of human pulmonary dirofilariasis.

Human pulmonary dirofilariasis has been documented from many parts of the world, but not in Korea so far. We experienced a patient of pulmonary dirofilariasis who had visited a local clinic because of chest pain for 1 month. On chest radiograph, a coin lesion of 2 cm diameter and enlargement of the mediastinal lymph node were shown. An exploratory lung resection was done. Pathologically the lesion was a pulmonary dirofilariasis complicated with necrotic pneumonia, fibrosis, and infarction. At the center of the lesion, degenerated nematode sections with multilayered cuticle, thick musculature, and bilateral internal ridges on each side were found, which was identified to be Dirofilaria immitis. This is the first report of human pulmonary dirofilariasis in Korea.

Isozyme electrophoresis patterns of the liver fluke, Clonorchis sinensis from Kimhae, Korea and from Shenyang, China.

An enzyme analysis of the liver fluke, Clonorchis sinensis from Kimhae, Korea and from Shenyang, China was conducted using a horizontal starch gel electrophoresis in order to elucidate their genetic relationships. A total of eight enzymes was employed from two different kinds of buffer systems. Two loci from each enzyme of aconitase and esterase (alpha-Na and beta-Na); and only one locus each from six enzymes, glucose-6-phosphate dehydrogenase (G6PD), alpha-glycerophosphate dehydrogenase (GPD), 3-hydroxybutyrate dehydrogenase (HBDH), malate dehydrogenase (MDH), phosphoglucose isomerase (PGI), and phosphoglucomutase (PGM) were detected. Most of loci in two populations of C. sinensis showed homozygous monomorphic banding patterns and one of them, GPD was specific as genetic markers between two different populations. However, esterase (alpha-Na), GPD, HBDH and PGI loci showed polymorphic banding patterns. Two populations of C. sinensis were more closely clustered within the range of genetic identity value of 0.998-1.0. In summarizing the above results, two populations of C. sinensis employed in this study showed mostly monomorphic enzyme protein banding patterns, and genetic differences specific between two populations.

Monoclonal antibodies to recombinant Der p 2, a major house dust mite allergen: specificity, epitope analysis and development of two-site capture ELISA.

House dust mite allergens have been well established as sensitizing agents that are important in the induction of allergic diseases. In order to analyze epitopes of the allergen and to develop a quantitative method of the allergen exposure, monoclonal antibodies against a recombinant Der p 2 (rDer p 2), one of the major allergens of Dermatophagoides pteronyssinus, were produced. Four monoclonal antibodies produced were species-specific and did not cross-react to the D. farinae crude extract. Two of the monoclonal antibodies were found to be IgG1 and the others were IgM. For the analysis of epitopes, a Der p 2 cDNA encoding 126 amino acids (aa) was dissected into three fragments with several overlapping peptides. A (aa residues 1-49), B (44-93), and C fragment (84-126). Three monoclonal antibodies showed reactivities to the recombinant B fragment and to the full-length rDer p 2, but one monoclonal antibody reacted only with the full-length rDer p 2. Two-site capture ELISA was developed using two different monoclonal antibodies for quantitating Der p 2 in house dust. The sensitivity limit was 4 ng/ml with rDer p 2 and 8 micrograms/ml with the D. pteronyssinus crude extract. The result suggested that the assay using monoclonal antibodies against rDer p 2 could be useful for the environmental studies and for the standardization of mite allergen extracts.

Identification of Chironomus kiiensis allergens, a dominant species of non-biting midges in Korea.

Non-biting midges are known to contain potent inhalant allergens. IgE antibody responses to the crude extract of Chironomus kiiensis adults, a dominant chironomid species in Korea, were examined. With the IgE-ELISA or passive cutaneous anaphylaxis reactions, increased levels of chironomid-specific IgE were detected in the skin test positive human sera, or immunized BALB/c mouse sera with the crude extract adsorbed to alum. IgE-immunoblot analysis showed major IgE-reacting protein band patterns, which reacted with more than 50% of the skin test positive human sera, at 110, 80, 73, 46, 40, 37, 34, and 31 kDa. The reactive band patterns were largely similar between skin test positive humans and immune BALB/c mice. However, the bands of 55, 31, 27, 26, 24, and 23 kDa were found only in sensitized humans, but not in immunized mice.

Karyotypes on three species of Chinese mesogastropod snails, Semisulcospira libertina, S. dolichostoma and Viviparus rivularis.

Three species of the families Viviparidae and Pleuroceridae, the first intermediate host of paragonimiasis, metagonimiasis and echinostomiasis were studied cytologically. The observed diploid chromosome number was as follows: Semisulcospira libertina 36, S. dolichostoma 34, and Viviparus rivularis 64. The mitotic chromosome complement of S. libertina has nine metacentric pairs and nine submetacentric pairs, and S. dolichostoma has three metacentric pairs and 14 submetacentric pairs of chromosomes. Viviparus rivularis showed two metacentric pairs and 30 submetacentric pairs of chromosomes.

A cytogenetic study on human intestinal trematodes of the genus Metagonimus (Digenea: Heterophyidae) in Korea.

In order to analyze chromosome numbers and karyotypes of intestinal trematodes belonging to the genus, Metagonimus, the gonad tissues of M. takahashii, M. miyatai, and M. yokogawai were prepared and examined. The number of bivalents in the first meiotic division of M. takahashii was nine (n = 9). The diploid number of M. miyatai was observed to be eighteen (2n = 18) and their chromosomes consisted of one pair of metacentric, 7 pairs of submetacentric, and one pair of telocentric chromosomes. The diploid number of M. yokogawai was thirty-two (2n = 32) and the chromosome complements were composed of two pairs of metacentric, 11 pairs of submetacentric, and three pairs of subtelocentric chromosomes. These results could be a supporting evidence for the validity of the new species, M. miyatai, distinct from M. yokogawai.

Karyotype analysis of Neodiplostomum seoulense.

A karyotype analysis of the chromosome of Neodiplostomum seoulense, one of causative agents of human intestinal trematodiasis, was done from the gonad tissue by the squashing method. The chromosome number was n = 10 and 2n = 20. Chromosome length was 1.30-4.0 microns. Chromosome pairs in the complement consisted of two pairs of metacentric, five pairs of submetacentrics/subtelocentric and three pairs of telocentric chromosomes. These data were comparable with those of other intestinal trematodes.