Hypereosinophilic Syndrome Presenting with Gastrointestinal Symptoms in an Adolescent / 계명의대학술지

Hypereosinophilic syndrome (HES) is defined as peripheral eosinophilia, organ involvement of eosinophils and exclusion of other disorders or dysfunction. HES is subclassified as myeloproliferative variant, T-lymphocytic, overlap, idiopathic, familial and associated type according to the new classification using molecular and immunologic markers. HES presenting with gastrointestinal symptoms is very rare but characterized by peripheral eosinophilia, eosinophilic infiltration of the gastrointestinal tract with other organs such as liver and bone marrow. We report a rare case of idiopathic HES in 18-year-old adolescent who presented with gastrointestinal symptoms including abdominal pain, diarrhea and ascites which resolved rapidly with corticosteroid therapy. HES should be included in the differential diagnosis of abdominal pain and ascites in children and adolescents.

The Combination of Real-Time PCR and HPLC for the Identification of Non-Tuberculous Mycobacteria

We used HPLC and AdvanSure real-time PCR (LG Life Sciences, Korea) to retrospectively analyze non-tuberculous mycobacteria (NTM) in 133 clinical specimens. The specimens were culture-positive for NTM and the HPLC method identified 130 strains of mycobacteria from the cultures (97.7%) at the species level. Among the isolates, 48 Mycobacterium. kansasii (36.1%), 39 M. intracellulare (29.3%), 17 M. avium (12.8%), 16 M. abscessus (12.0%), 6 M. fortuitum (4.5%), 2 M. szulgai (1.5%), 2 M. gordonae (1.5%), and 3 unclassified NTM strains (2.3%) were identified. The real-time PCR assay identified 60 NTM-positive specimens (45.1%), 65 negative specimens (48.9%), and 8 M. tuberculosis (TB)-positive specimens (6.0%). The real-time PCR assay is advantageous because of its rapid identification of NTM. However, in our study, the real-time PCR assay showed relatively low sensitivity (45.1%) when using direct specimens including sputum and bronchoalveolar lavage (BAL) fluid. HPLC is useful as it discriminates NTM at the species level, although it is time-consuming and requires specific equipment and technical expertise. A combination of both methods will be helpful for the rapid and accurate identification of mycobacteria in clinical laboratories.

Performance Evaluation of 3 Kinds of HBsAg Qualitative Assays and 2 Kinds of Quantitative Assays

BACKGROUND: Currently used techniques for quantitation of HBsAg often yield discordant results; therefore, development of quantitation techniques that can detect HBsAg with high accuracy has become very important. Recent advances have led to the development of several HBsAg detection systems. Here, we evaluated the performance of 3 newly developed detection systems, which can detect HBsAg both qualitatively and quantitavely, and determined the concordance among their results. METHODS: Four hundred and thirty two samples assigned to 4 groups-patient group, dilution group, weakly reactive group, and linearity group- were subjected to qualitative and quantitative detection of HBsAg by using the 3 systems developed by 3 major manufacturers; Abbott Architect, Roche E170 and Siemens Centaur XP. RESULTS: The results for the qualitative analyses were closely concordant among the three systems (98.3%) for all 432 samples. In 123 samples that were determined as HBsAg-negative, E170 (76%) distributed frequently at the upper half level (0.5-1.0) of negative reference range, compared with Architect (11%) and Centaur XP (22%). In particular, in 65 samples that were diluted from the strongly positive samples to obtain weakly positive samples, the average index values obtained using Architect (3.6 S/CO), E170 (4.2 COI) and Centaur XP (11.4 index value) differed significantly (P<0.0001). In the antiviral treatment group and the post-liver transplantation group, no inconsistency was observed among the results of the qualitative and quantitative assays. In the 18-fold serially diluted samples, no linearity was observed. CONCLUSIONS: Because of the possibility of false-positive detection in the HBsAg-negative samples, regular management of equipment and appropriate selection of reagents are very important. In weakly positive samples, quantitative assay has not to be replaced for qualitative assay. Therefore, the qualitative assays should be used for screening the samples, whereas the quantitative assays should be used for monitoring the Hepatitis B virus (HBV) load in the samples determined as HBsAg-positive. The qualitative index value should not be interpreted as a quantitative measure of HBV load.

Performance Evaluation of Immunoassay Detection of HBsAg Mutants and Their Clinical Significance in the High Risk Groups

BACKGROUND: False negative results have been reported in the immunodetection of hepatitis B virus (HBV) because of the existence of the various mutants of the virus, causing most suppliers to try to develop superior reagents by using highly sensitive and specific monoclonal or polyclonal antibodies. In this study, we evaluated the effectiveness of 3 newly developed reagents by major manufacturers by adopting automated methods with increased sensitivity and specificity in the detection and discrimination of native and recombinant mutant antigens. METHODS: We analyzed samples confirmed positive for hepatitis B surface antigen (HBsAg), high-risk samples from chronic hepatitis patients treated with antiviral agents, and samples from patients who had undergone liver transplantation and were treated with high-dose hepatitis B immunoglobulin (HBIG) by using reagents and systems newly developed by Abbott Laboratories (USA), Roche Diagnostics (Germany), and Siemens Healthcare Diagnostics (USA). Recombinant sample panels from these manufacturers with low and high concentrations were also analyzed for comparing the 3 reagents. RESULTS: There were no discrepant results among the various selected patient groups; however, for the recombinant mutant panels, all of the 3 reagents showed highly positive detection rates for their corresponding mutant panels, but showed relatively discrepant mutant detection rates when cross-tested with the other mutant panels. Detection rates of the HBsAg mutant panels were higher at a higher concentration of the mutant samples, but were lower for the same mutant receptor sites at a lower concentration. CONCLUSIONS: The 3 major detection methods seem to recognize the major native mutants commonly encountered in clinical practice. However, in the case of recombinant mutants, we believe that our data are not to be interpreted as a reference standard for any reagent, because the results can only be validated for the reagents' corresponding mutant panels; such results tend to be mutually exclusive, and the enough concentration of mutants was required to be adjusted for a comparative analysis.

Lung Infection Caused by Mycobacterium riyadhense Confused with Mycobacterium tuberculosis: The First Case in Korea

A slowly growing, non-chromogenic mycobacterial strain was isolated from sputum and bronchial lavage fluid samples of a patient presenting with productive cough, blood-tinged sputum, low-grade fever, and weakness. A positive acid-fast bacilli sputum smear result prompted the initiation of an anti-tuberculosis regimen. Multiplex real-time PCR showed a negative result for Mycobacterium tuberculosis complex and a positive result for nontuberculous mycobacteria. The DNA chip test confirmed this organism as a member of the genus Mycobacterium, but could not specify the species. Interestingly, the mycolic acid patterns obtained by HPLC nearly overlapped with those of M. simulans. The sequences of the Mycobacterium 16S rRNA gene and 16S-23S internal transcribed spacer region were unique and were found to have 100% similarity with those of M. riyadhense. After a review of the literature, we report this case as the first Korean case of M. riyadhense lung infection.

Comparison of an Automated Repetitive Sequence-based PCR Microbial Typing System with IS6110-Restriction Fragment Length Polymorphism for Epidemiologic Investigation of Clinical Mycobacterium tuberculosis Isolates in Korea / 대한진단검사의학회지

Tuberculosis remains a severe public health problem worldwide. Presently, genotyping is used for conducting epidemiologic and clinical studies on tuberculosis cases. We evaluated the efficacy of the repetitive sequence-based PCR (rep-PCR)-based DiversiLab(TM) system (bioMerieux, France) over the IS6110-restriction fragment length polymorphism analysis for detecting Mycobacterium tuberculosis. In all, 89 clinical M. tuberculosis isolates collected nationwide from Korea were used. The DiversiLab system allocated the 89 isolates to 8 groups with 1 unique isolate when a similarity level of 95% was applied. Seventy-six isolates of the Beijing family and 13 isolates of non-Beijing family strains were irregularly distributed regardless of rep-PCR groups. The DiversiLab system generated a rapid, sensitive, and standardized result. It can be used to conduct molecular epidemiologic studies to identify clinical M. tuberculosis isolates in Korea.

A Case of Death Due to Hemophagocytic Lymphohistiocytosis Accompanied by Scrub Typhus

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease with a high mortality rate. It is associated with a variety of bacterial, viral, fungal, and parasitic infections. In the literature, there are several cases of HLH associated with scrub typhus in adults, all of which were successfully treated with antibiotic therapy for scrub typhus. This report describes a case of HLH accompanied by scrub typhus in an 81-year-old woman, in whom the disease progressed despite doxycyclin therapy. The patient refused to receive immunosuppressive chemotherapy for HLH and died 5 weeks after admission due to multi-organ failure. To our knowledge, this is the first case of death due to scrub typhus-associated HLH in an adult.

Identification of Mycobacteria Species by HPLC and Species Distribution during Five Years at Ulsan University Hospital / 대한진단검사의학회지

BACKGROUND: Infections caused by mycobacteria have been significantly increasing. Due to the difficulty of making a decision about the pathogenicity of mycobacteria, species-level identification is very important for patients' diagnosis and treatment. The purpose of this study was to identify mycobacteria species using a high performance liquid chromatography (HPLC) method and to provide an initial database for the distribution of mycobacteria in Korea. METHODS: Acid fast bacteria isolated from 3,107 clinical specimens were identified by mycolic acid analysis using HPLC. The HPLC patterns were compared with those of standard mycobacteria species. RESULTS: The HPLC patterns were divided into single, double, and triple cluster groups, each group comprising 9, 20, and 4 species, respectively. Mycobacteria and non-tuberculous mycobacteria (NTM) were identifies by HPLC at the rates of 99.5% and 95.6%, respectively. NTM was isolated in 12.4% of the mycobacteria positive specimens. This study also found that there were 20 different NTM species with the distribution of each species ranging from 0.3% to 15.9% of the total NTM. While the rate of NTM has been increasing in Korea, M. avium-intracellulare, M. fortuitum, and M. chelonae are relatively decreasing, and M. kansasii and M. gordonae are relatively increasing. CONCLUSIONS: HPLC method was highly discriminative for the identification of NTM in clinical specimens.

Clinical significance of E. coli O26 isolates on urine specimen of urinary tract infection / 대한산부인과학회지

OBJECTIVE: Escherichia coli (E. coli) O26 has been the most common type of non-O157 human isolates and it has been related with urinary tract infection and its sequelae. So we investigated the clinical significance of E. coli O26 among the cases of urinary tract infection. METHODS: From January, 2005 to December, 2007, the 22 E. coli isolates that were related with urinary tract infection were analyzed. The isolates were identified biochemically by Vitek 1. We performed antisera test by O157, O26, O111 diagnostic antisera about the 22 E. coli isolates. We reviewed clinical history of the same patients retrospectively. RESULTS: 331 E. coli isolates in the urine specimen were isolated from January, 2005 to December, 2007. 175 E. coli isolates that were related with urinary tract infection were analyzed by O157, O26, O111 antisera test. As a result, 22 isolates (13.5%) were O26 antisera positive. There were 8, 3, and 2 cases of watery diarrhea, hemolytic uremic syndrome, thrombotic thrombocytopenic purpura repectively. CONCLUSION: In our study, because E. coli O26 was pathogenic and developed major complications, we concluded that patients with urinary tract infection with E. coli. should examine the antisera test about E. coli O157 and O26.

Distribution and Clinical Significance of Nontuberculous Mycobacteria Identified by High Performance Liquid Chromatography in Clinical Specimens / 대한임상미생물학회지

BACKGROUND: Infections caused by nontuberculous mycobacteria (NTM) are significantly increasing over the last decade. Due to the uncertainty in the clinical significance of these organisms, their effective diagnosis and treatment has been challenging. The purpose of this study was to investigate the distribution and clinical significance of NTM in clinical specimens. METHODS: Acid-fast culture positive 3,107 clinical specimens were identified by mycolic acid analysis using high performance liquid chromatography (HPLC.) The HPLC patterns of 384 NTM strains were compared with those of standard mycobacterium species. Clinical significance of NTM was investigated by a retrospective study including acid-fast stain and culture, medical history, symptoms and signs, radiological and other laboratory findings, pathologic findings, response to treatment, and follow-up study, and was confirmed according to the guideline of American Thoracic Society. RESULTS: Among the 3,107 Mycobacterium-positive specimens, 384 (12.4%) were found to be positive for NTM. Of these, 367 (95.6%) were successfully identified by HPLC as 19 different species, each of which comprising 0.3% to 15.9% of the total NTM, Studies on the pathogenic role of NTM showed that 0~79.6% of each species or 0~100% of isolates from each specimen could be considered clinically significant. CONCLUSION: HPLC method is highly discriminative for the identification of NTM in clinical specimens. When NTM is isolated from clinical specimens in the Ulsan area, the findings from this study could serve as a database on which to determine its clinical significance depending on species type and also specimen type.

Experience with the Automatic Blood Bank Instrument AutoVue Innova / 대한수혈학회지

BACKGROUND: The AutoVue Innova (Ortho Clinical Diagnostic, Raritan, NJ, USA) is an automatic instrument for blood bank tests, and it has recently been introduced in Korea for the first time at our hospital. This instrument employs column agglutination technology and it performs blood bank tests automatically. We evaluated this instrument and we report on the results. METHODS: We performed ABO/RhD typing and antibody screening for 250 randomly selected samples, and crossmatching for 261 samples with using the AutoVue Innova in parallel with the conventional manual methods. For a sensitivity test, we added 3 samples of A(2)B(3) and 2 samples of weak-D and serially diluted reagent antisera to the test pool and we measured turnaround time (TAT) for the antibody screening test. RESULTS: The concordance rates between AutoVue Innova and the manual methods for ABO/RhD blood typing, antibody screening and crossmatching tests were 99.6%, 100% and 98.9%, respectively. The overall retest rate was 0.5% and the main cause of the discrepancy was revealed to be hemolysis or an inadequate amount of the samples. The overall sensitivity of AutoVue Innova seems to be same as or better than the manual methods. The TAT for the antibody screening test was significantly shorter for the AutoVue Innova (64+/-43 min, n=512) than for the tube method (89+/-57 min, n=99) (P<0.001). CONCLUSION: The test results of AutoVue Innova were accurate and sensitive for the ABO/RhD typing, crossmatching and antibody screening tests. The TAT for the antibody screening test was remarkably shortened up to five times more samples could be tested without an increase of manpower.

The Frequency and Related Factors of Masked Hypertension among Volunteers

BACKGROUND: 'Masked Hypertension' is a phenomenon of blood pressure that is normotensive by clinic measurement but proves to be hypertensive by 24 hour-AMBP and is associated with many cardiovascular complications and its clinical importance has become the center of public interest. However, in Korea no study concerning masked hypertension has ever been published so far. We investigated the frequency and the related factors of masked hypertension among Koreans. METHODS: Overall, 53 volunteers from Incheon and Seoul, Korea, who were 40 years old and abov were enrolled from August 2003 to August 2004. We checked their blood pressure and pulse rate every hour using an ambulatory blood pressure monitoring device [SpaceLabs 90207] for 24 hours. Masked hypertension was defined as office mean BP less than 140/90 mmHg and daytime mean BP over 135/85 mmHg. RESULTS: Among the total, 15 subjects met the criteria of masked hypertension (28.3%) Current smoking (P=0.021), higher clinic mean SBP (P=0.011) and DBP (P=0.027), and prehypertension (P=0.04) were identified as related factors. And when adjusted for sex by logistic regression, only current smoking was statistically significant (P=0.039) and prehypertension showed borderline significance (P=0.092) (CI=95%). Additionally, mean pulse pressures and mean standard deviation of individual mean SBP were higher in the masked hypertension group. CONCLUSION: The frequency of masked hypertension was 28.3% the and related factors were current smoking and higher office BP, especially prehypertension that was introduced in JNC-7. The fact that the pulse pressure and the variability of individual SBP were higher in the masked hypertension group remains thought-provoking.

A Case of Group O Losing Anti-B Selectively / 대한수혈학회지

We report a case of group O losing anti-B selectively. A 25-year-old male donated blood; on the donor test an ABO discrepancy was noted, and a further evaluation study was performed. ABO genotyping with an allele specific polymerase chain reaction assay revealed O/O and DNA sequencing of exons 6 and 7 of the ABO gene showed O01/O02. The serum gammaglobulin level was decreased and only 0.2% CD19 pan-B positive lymphocytes were present in a subset of lymphocytes. In a previous donor study, anti-B of the patient was lost from a third donor study and was still not detected.

Drug Susceptibility and Clinical Significance of Rapidly Growing Mycobacteria Isolated from Patients with Non-Tuberculous Mycobacteriosis / 대한임상미생물학회지

BACKGROUND: It is recommended that all rapidly growing mycobacteria (RGM) isolated from patients with mycobacteriosis are subjected to antimicrobial susceptibility testing. The current study was aimed to perform susceptibility test on clinical strains of RGM isolated from patients with mycobacteriosis and to determine the clinical significance of the isolates. METHODS: For 17 patients with RGM infection from 2002 to 2006 at Ulsan University Hospital, medical records were reviewed retrospectively and anti-mycobacterial susceptibility test was performed for the clinical isolates by broth microdilution method. RESULTS: Rates of susceptible strains of RGMs against individual drugs were as follows: amikacin 100%, cefoxitin 59%, ciprofloxacin 82%, clarithromycin 71%, doxycycline 18%, imipenem 91% (M. fortuitum), sulfamethoxazole 71%, and tobramycin 100% (M. chelonae). Ten of the 17 nontuberculous mycobacteria (NTM) patients had been treated with anti-tuberculosis drugs initially. Anti-tuberculosis drugs were continued in 3 patients and changed to other antimicrobial agents effective to NTM in 4 patients, all of whom were cured. Five of 7 NTM patients who had been treated with anti-NTM treatment were cured. All isolates from the patients treated with anti-NTM drugs were susceptible to at least one of the drugs administered. CONCLUSION: Clinical isolates of RGMs showed fully susceptible to amikacin, while highly resistant to doxycycline and variable to other drugs depending on the species.

Standardization of the Korean Version of Patient Health Questionnaire-9 as a Screening Instrument for Major Depressive Disorder

BACKGROUND: Depression is the most frequently encountered mental disorder in primary care. In it is necessary to order to, have a screening tool has high sensitivity and specificity and consumes less time. Therefore, the aim of this study was to assess the validity of the Korean version of Patient Health Questionnaire-9 (PHQ-9). METHODS: A convenience sample of 160 ambulatory patients in a family practice clinic at Inha university hospital and the health care center at Bakae hospital received the Korean version of PHQ-9. Then the subjects were interviewed by a resident of family medicine according to DSM- IV criteria. The sensitivity, the specificity, the likelihood ratio, the ROC curve, the validity and the reliability of the Korean version of PHQ-9, and the consumptive time were examined. RESULTS: There were 22 pationts in the depression group and 138 in the non-depression group. The Cronbach's alpha was 0.852. The sensitivity and the specificity were 81.8% and 89.9%, respectively, and the positive likelihood ratio was 8.10. The area under curve had an excellent value, 0.944 (P<0.05). The consumptive time was 2.66+/-1.13 minutes. CONCLUSION: The Korean version of PHQ-9 hay a good reliability and validity, less consumptive time, and easy calculating score. Therefore, the Korean version of PHQ-9 seems to be a useful measure for detecting depression in primary care.

A Case Report of Disseminated Extranodal Marginal Zone B-Cell Lymphoma of MALT Manifested by Solitary Pulmonary Nodule / 결핵및호흡기질환

Extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) is usually indolent. Although it was reported recently that about 20-30% cases of MALT lymphoma presented with a disseminated disease at diagnosis, it was described as a disease localized at diagnosis and remaining stable for a prolonged period. However, only a few cases of MALT lymphoma involved the lung and gastrointestinal tract all at once. We report a case of a 73-year-old man with disseminated MALT lymphoma. He presented with non-productive cough, initial chest radiograph showed a nodule in the right lower lobe. The diagnosis of stage IV MALT lymphoma was made by CT scan, video-assisted thoracoscopic excisional biopy, gastrofiberscopic biopsy and bone marrow biopsy. The lymphoma involved the lung, stomach and bone marrow at the time of diagnosis. Because he refused chemotherapy, he discharged after Helicobacter pylori eradication without chemotherapy. Regular follow-up examination did not show any evidence of disease progression over 22 months.

The Relation of Health-related Behaviors and Family Function in Adolescents

BACKGROUND: It is well known that family is not only the basis but also one of the major factors for personal health management. In this study, we examined to find out the association of family function with health behavior. METHODS: From June to August, 1999, a total of 800 middle and high school students, selected from several metropolitan, medium and small sized cities and a 'myon', were questionnaired on their health-related behaviors like smoking, alcohol intake, diet, exercise and sleeping by means of 'Korean Family Function Assessment Tool'. RESULTS: Among the total, 599 students gave appropriate answers. They were composed of 323 (53.9%) middle school and 276 (46.1%) high school students. Male to female sex ratio was 307 (51.3%) to 292 (48.7%). In the aspect of smoking, smoking group and non-smoking group showed 127.0 +/- 23.3 and 144.9 +/- 23.6, respectively, in terms of Korean Family Function Assessment Tool and were statistically significant (P<0.01). The students were divided into three groups as heavy alcohol drinkers who consumed alcohol more than 168 g-in case of girls the datum point was 132 g-per week, light drinkers and non-drinkers. Their KFFAT scores were also significantly different from each other (P<0.01). On tukey multiple comparison, there was a significant difference primarily between the drinkers and the non-drinkers (P<0.05). Similer findings were shown between the regular and the irregular diet group (P<0.01). But there as no significance with respect to exercise and sleeping. CONCLUSION: Among the health-related behaviors of adolescents, smoking, alcohol intake and diet habit were significantly associated with family function, but exercise and sleeping were not.

The Relation between Father's and Adolescent's Health Behavior

BACKGROUND: Adolescence is an important period with respect to health promotion, because development of health behavior at this stage is the foundation of health in adalts. Among the social factors, family factor which affects the primary social function can be the most fundamental. We investigated the effects of father's health behavior on the health behavior of their children during adolescence. METHODS: From June to August 1999, 300 adolescent students from middle schools and high schools of areas including four cities (Seoul, Incheon, Anyang, Gunpo) and their fathers were questioned about general characteristics and health behavior such as smoking, alcohol drinking, exercise, duration of sleep, body weight, height and eating habits for breakfast ('Alameda 7'). The relationship between father's health behavior and their adolescents' health behavior was analyzed by chi-squared test. RESULTS: Among 300 adolescents and their fathers, 211 pairs responded appropriately to the questionnaires. Adolescent's smoking was not associated with father's smoking. In drinking there was no significant association between father and adolescent, but in drinking amount, father's high drinking amount was significantly associated in all students, especially in females and high school students. Regular diet, exercise, sleep did not show significant association between father and adolescent. The proportion of obesity in adolescents whose fathers were obese was significantly greater compared to those whose fathers were not. CONCLUSION: High drinking amount and obesity had a statistical significance of association between fathers and adolescents. When we consider adolescents' health behavior, their fathers' health behavior must be considered.

The Relation between Father's and Adolescent's Health Behavior

BACKGROUND: Adolescence is an important period with respect to health promotion, because development of health behavior at this stage is the foundation of health in adalts. Among the social factors, family factor which affects the primary social function can be the most fundamental. We investigated the effects of father's health behavior on the health behavior of their children during adolescence. METHODS: From June to August 1999, 300 adolescent students from middle schools and high schools of areas including four cities (Seoul, Incheon, Anyang, Gunpo) and their fathers were questioned about general characteristics and health behavior such as smoking, alcohol drinking, exercise, duration of sleep, body weight, height and eating habits for breakfast ('Alameda 7'). The relationship between father's health behavior and their adolescents' health behavior was analyzed by chi-squared test. RESULTS: Among 300 adolescents and their fathers, 211 pairs responded appropriately to the questionnaires. Adolescent's smoking was not associated with father's smoking. In drinking there was no significant association between father and adolescent, but in drinking amount, father's high drinking amount was significantly associated in all students, especially in females and high school students. Regular diet, exercise, sleep did not show significant association between father and adolescent. The proportion of obesity in adolescents whose fathers were obese was significantly greater compared to those whose fathers were not. CONCLUSION: High drinking amount and obesity had a statistical significance of association between fathers and adolescents. When we consider adolescents' health behavior, their fathers' health behavior must be considered.

Expression of Cyclooxygenase-2 and Matrix Metalloproteinases in Sinonasal Tumor / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The matrix metalloproteinases (MMPs) have been associated with tumor cell invasion and metastasis by mediating the degradation of extracellular matrix components. Cyclooxygenase-2 (COX-2) plays an important role in promotion of carcinogenesis, tumor invasiveness and angiogenesis. Recently, some investigators have reported that COX-2 could promote secretion of MMP-2 and MMP-9. Therefore, an interrelation between MMPs and the associated COX-2 may play a significant role in the invasive phenotype of malignant tumors. In the present study, the authors investigated the correlation between expressions of COX-2 and MMPs. MATERIALS AND METHOD: Immunohistochemical staining of MMP-2, -3 and -9, and COX-2 were performed on paraffin-embedded tissue sections of 51 nasal cavity and paranasal sinuses tumors (27 inverted papillomas, 5 inverted papillomas with malignant transformation, and 19 squamous cell carcinomas). Co-expression of these MMPs and COX-2 was visualized with confocal laser scanning microscope. RESULTS: MMP-2, -3 and -9 were found mainly in malignant lesions in concert with COX-2. However, the co-expressions of MMP-2 and COX-2, MMP-9 and COX-2 were detected with significance. CONCLUSION: These results suggest a potentially important role for COX-2 in the regulation of MMPs, malignant transformation, and progression of squamous cell carcinoma, and it points out the potential use of COX-2 inhibitors, in the prevention and treatment of squamous cell carcinoma of nasal cavity and paranasal sinuses.