The Diagnostic Value of Ultrasound-Guided Cervical Core Needle Biopsy in Diagnosis of Lymphoma in Suspected Patients.

Background: Core needle biopsy (CNB) guided by imaging modalities seems to be an acceptable modality for diagnosis of lymphoma due to its safety, good applicability, availability as well as diagnostic accuracy, however; Studies have not reached a consensus on its diagnostic accuracy and factors affecting its performance. The present study aimed to assess the value of ultrasound-guided cervical CNB in the diagnosis of lymphoma in suspected patients. Materials and Methods: This cross-sectional study was performed on 46 consecutive patients (20 to 82 years) with cervical mass or lymphadenopathy suspected of lymphoma and were candidates for diagnostic evaluation. Ultrasound-guided core needle biopsies (UGCNB) were done by a single radiologist under guided ultrasonography. The diagnostic value of UGCNB in the diagnosis and determination of specific lymphoma subtypes was assessed. Results: Using UGCNB led to the diagnosis of lymphoma in 34.8% and non-lymphoma lesions in 43.5%, while the diagnosis remained unclear in other 21.7% with a total UGCNB-based identification rate of 78.3%. No patient with lymphoma was missed. All patients were followed up over a 6-month period. In none of the cases, clinical diagnosis and treatment response were found contrary to the initial pathologic diagnosis. No significant complication such as hematoma or infection was reported. Conclusion: UGCNB has a high diagnostic value for determining the nature of the cervical lesions suspected of lymphoma.

Ectopic intrathyroidal thymic tissue in an adult patient: a case report and review of the literature.

BACKGROUND: Ectopic intrathyroidal thymic tissue is a rare diagnosis, specifically in adults. Such ectopic tissue is usually misdiagnosed as benign or malignant thyroid lesions and is mainly investigated by ultrasonography and pathologic examination. CASE PRESENTATION: We present the case of an adult 31-year-old Persian female patient with a cervical mass and no other significant medical history. The lesion had hypo- to isoechoic features on sonographic imaging, and needle aspiration examination revealed lymphoid cells suspicious of lymphoid malignancies. However, pathologic examination after resection of the lesion showed normal thymic tissue. CONCLUSIONS: The rare entity of ectopic thymic tissue within the thyroid gland in adult patients requires meticulous examination by clinicians, radiologists, and pathologists to diagnose the condition with high accuracy and plan appropriate management.

Prognostic Significance of Cancer Stem Cell Markers in Patients With Salivary Gland Carcinomas.

OBJECTIVES: Cancer stem cells (CSCs) are a small group of cells resistant to therapy and play a major role in tumor progression, recurrence, and poor clinical outcomes of patients. This study aimed to evaluate the association of CSC markers with clinicopathologic features and survival in patients with salivary gland carcinomas (SGCs). MATERIALS AND METHODS: The medical records of 48 patients affected by mucoepidermoid carcinoma (MEC) and 47 patients with adenoid cystic carcinoma (AdCC) were reviewed retrospectively. SOX2, CD133, and CD44 expression was appraised by immunohistochemistry and statistically analyzed to weigh the correlation between these markers and patients' clinicopathologic features and tumor outcomes. RESULTS: In AdCC patients showing poor outcomes, a trend toward a high expression of CD133 and CD44 and low expression of SOX2 was observed, while in MEC patients experiencing the same outcomes, there was a trend toward a high expression of CD44 and low expression of CD133 and SOX2. Only the increase of MEC histopathologic grade was statistically significant with decreased SOX2 expression. Distant metastasis in AdCC patients, tumor grade, lymph node involvement, and local recurrence in MEC patients had significant correlations with patients' survival. CONCLUSION: Besides the significant association between low SOX2 expression and higher grades of MEC, we found no statistically significant correlation between the studied CSC markers and patients' survival or clinicopathologic features. Therefore, a larger sample size with long-term follow-up is beneficial for thorough investigations toward the main role of CSCs in patients with SGCs.

Clinical Significance and Prognostic Value of SOX2 Protein Expression in Patients With Oral Squamous Cell Carcinoma.

OBJECTIVES: Cancer stem cells are a small group of highly tumorigenic cells with the trend of self-renewal, tumor progression, metastasis, recurrence, and therapeutic resistance. SOX2 is an important cancer stem cell marker that is involved in tumorigenesis and correlated with aggressive features in various types of malignancies. The present study was aimed to investigate the expression of this biomarker in neoplastic tissues of oral squamous cell carcinoma (OSCC) to determine whether it has the potential to predict the outcomes and survival of the affected patients. MATERIALS AND METHODS: The medical records of 73 patients diagnosed with OSCC were retrospectively studied. Clinical and pathologic features included age, sex, tumor size, histologic grade, lymph node involvement, recurrence, metastasis, and follow up. Immunohistochemical analysis for SOX2 protein expression was performed, and its correlations with clinicopathologic features were evaluated. RESULTS: SOX2 was significantly associated with tumor size, lymph node metastasis, and patients' survival. We found no apparent correlation between SOX2 and tumor recurrence, distant metastasis, or differentiation. The multivariate analysis identifies patients' age, sex, and SOX2 expression as independent prognostic factors for overall survival. CONCLUSION: SOX2 may worsen the prognosis and be a progressive malignant factor, which can help clinicians investigate OSCC patients' survival and plan the appropriate treatment accordingly.

Expressão estromal e epitelial de syndecan-1 em tumores de glândulas salivares benignos e malignos: qual delas reflete melhor o comportamento? / Stromal and epithelial syndecan-1 expression in benign and malignant salivary gland tumors: which is more reflective of behavior?

Resumo Introdução: Tumores de glândulas salivares são um grupo diversificado de lesões, com várias origens e comportamentos extremamente diferentes, resultam em distintos desfechos para os pacientes. Portanto, a necessidade de descobrir novos marcadores com a capacidade de predizer o comportamento de neoplasias de glândulas salivares benignas e malignas é crucial. O syndecan-1 é uma proteína da superfície celular com papéis significativos em vários aspectos da função tumoral. Sua expressão nas neoplasias das glândulas salivares, especialmente seu componente estromal, ainda não foi investigada. Objetivos: Avaliar a imunopositividade do syndecan-1 nos componentes epiteliais e estromais das neoplasias de glândulas salivares e compará-la entre os subtipos benigno e maligno, além de avaliar sua correlação com os parâmetros clínico-patológicos. Método: Foram corados 133 tumores de glândulas salivares imuno-histoquimicamente com syndecan-1 e a intensidade e porcentagem dessa proteína foram determinadas, comparadas entre as lesões e correlacionadas com fatores clínico-patológicos. Resultados: A análise estatística das lesões com tamanho amostral suficiente mostrou diferenças significantes em porcentagem e intensidade entre os componentes epiteliais e estromais de todos os tumores (p < 0,05). As comparações pareadas demonstraram uma porcentagem de coloração significantemente maior das células epiteliais (p = 0,02) no tumor de Warthin em comparação com o adenoma pleomórfico e o carcinoma adenoide cístico. Da mesma forma, foram observadas intensidades de coloração e/ou percentagens significantemente maiores no carcinoma mucoepidermoide e no carcinoma adenoide cístico em comparação ao adenoma pleomórfico e ao tumor de Warthin (p < 0,05). Dos fatores clinico-patológicos, houve apenas uma correlação negativa significante entre o percentual estromal de carcinoma mucoepidermoide e a idade; e uma diferença significante entre a intensidade estromal + porcentagem de carcinoma adenoide cístico e sexo (p < 0,05). Conclusões: De acordo com nossos achados, o syndecan-1 estromal se correlaciona com o comportamento maligno de tumores de glândulas salivares, demonstra uma expressão mais alta, indica um papel para o syndecan-1 na invasão e metástase tumoral.

Stromal and epithelial syndecan-1 expression in benign and malignant salivary gland tumors: which is more reflective of behavior?

INTRODUCTION: Salivary gland tumors are a diverse group of lesions, with various origins and extremely different behaviors, leading to a variety of outcomes for patients. Therefore, the need to discover novel markers with the ability to predict the behavior of benign and malignant salivary gland neoplasms is crucial. Syndecan-1 is a cell-surface protein with significant roles in various aspects of tumor function. Its expression in salivary gland neoplasms, especially their stromal component, has not been investigated. OBJECTIVES: We aimed to assess the immunopositivity of syndecan-1 in epithelial and stromal components of salivary gland neoplasms and to compare it between benign and malignant subtypes in addition to evaluating its correlation with clinicopathologic parameters. METHODS: 133 salivary gland tumors were immunohistochemically stained with syndecan-1 and the intensity and percentage of this protein was determined, compared between the tumors and correlated with clinicopathologic factors. RESULTS: Statistical analysis of lesions with a sufficient sample size showed significant differences in percentage and intensity between both epithelial and stromal components of all tumors (p<0.05). Pairwise-comparisons demonstrated significantly higher staining-percentage of epithelial cells (p=0.02) in Warthin's tumor compared to pleomorphic adenoma and adenoid cystic carcinoma. Similarly, significantly higher staining intensities and/or percentages was observed in mucoepidermoid carcinoma and adenoid cystic carcinoma compared to pleomorphic adenoma and Warthin's tumor (p<0.05). Of the clinicopathologic factors, there was only a significant negative correlation between stromal percentage of mucoepidermoid carcinoma and age and a significant difference between stromal intensity+percentage of adenoid cystic carcinoma and gender (p<0.05). CONCLUSIONS: According to our findings we postulate that stromal syndecan-1 correlates with the behavior of salivary gland tumors, with malignant neoplasms demonstrating a higher expression, indicating a role for syndecan-1 in invasion and metastasis.

Methylation Assessment of Two DKK2 and DKK4 Genes in Oral Squamous Cell Carcinoma Patients.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most important types of oral malignancies. DKK gene family members as well as DKK2/4 have critical roles in regulation of Wnt signaling as one of the main determining pathway in oral carcinogenesis. This study aimed to identify promoter methylation status of DKK2/4 genes to provide possible biomarkers for early detection and treatment of OSCC patients. METHODS: A case control study was performed on 31 fresh tissues obtained from oral cavity of patients affected by OSCC and 31 fresh corresponding tissues from normal healthy controls in Tehran and, between the years of 2016-2018. Purified DNA from tissue samples was subjected to bisulfite treatment and then methylation specific polymerase chain reaction (MSP-PCR) was carried out on treated DNA samples. RESULTS: DKK4 promoter was methylated in none of OSCC samples while it was methylated in 16.1% of healthy controls. 16.1% of OSCC samples were detected to be semimethylated and 22.6% of healthy normal samples were methylated for DKK2 promoter gene. Meaningful difference was found in DKK4 promoter methylation among OSCC patients and healthy controls. Significant correlation was found between DKK4 promoter methylation and tumor grade. The age of all enrolled samples was demonstrated to have strong effect on promoter methylation of studied genes. CONCLUSION: Hypomethylation of DKK2 and DKK4 genes in higher grades of OSCC samples may indicate the pivotal role of their expression in tumor cells invasion and progression through modulation of Wnt signaling pathway. Further study required to determine simultaneous expression of those genes and Wnt signaling elements at mRNA and protein levels.

Expression Analysis of GRHL3 and PHLDA3 in Head and Neck Squamous Cell Carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) includes a group of heterogeneous tumors with generally invasive behavior. The PI3K/AKT pathway plays an important role in the pathogenesis of HNSCC. METHODS: In the current study, we investigated the expression of two negative feedback regulators of the PI3K pathway, namely PHLDA3 and GRHL3, in 45 paired samples of HNSCC and adjacent non-cancerous tissues (ANCTs). RESULTS: While expression of GRHL3 was down-regulated in tumoral tissues compared with ANCTs by the factor 4.21, PHLDA3 expression levels were up-regulated by 5.99-times. Gender-based analysis revealed a significant down-regulation of GRHL3 gene expression level in male patients compared with the control samples and significant up-regulation of PHLDA3 gene expression level in both sexes compared with the control samples. Differences in the expressions of both genes were significant in patients aged more than 60 years, but not in the younger patients. Expression of GRHL3 was only down-regulated in patients with positive smoking history. Expression of GRHL3 was decreased in grades 2 and 3 samples compared with controls. There was a significant increase in transcript levels of PHLDA3 in stages II and III HNSCC samples compared with the controls group. ROC curve analysis indicated that the expression level of PHLDA3 could be a promising marker for the diagnosis of HNSCC patients with a sensitivity and specificity of 0.666 and 0.688, respectively. In addition, sensitivity and specificity of GRHL3 were 0.755 and 0.577, respectively. DISCUSSION: The current study indicates dysregulation of regulators of PI3K pathway in HNSCC and their potential application as putative biomarkers for this cancer.

Comparative Analysis of P63, Maspin and Matrix Metalloproteinase 2 Expression in Mucoepidermoid Carcinoma and Adenoid Cystic Carcinoma of Salivary Glands.

STATEMENT OF THE PROBLEM: The tumor suppressor role of myoepithelial cells and related mechanisms in breast tumors are well understood. However, the role of these cells in tumors of salivary glands is debatable. PURPOSE: The present study was designed to determine the expression of p63, mammary serine protease inhibitor (maspin) and matrix metalloproteinase 2 (MMP-2) in mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ADCC) of salivary glands due to various cellular differentiation and structure. The association between the expression of these markers and clinicopathologic features and myoepithelial differentiation were also evaluated. MATERIALS AND METHOD: P63, maspin, and MMP-2 expression were immunohistochemically studied in 67 cases including35 cases of MEC and 32 cases of ADCC. The smooth muscle actin (SMA) staining was also applied to confirm the presence of myoepithelial differentiation. Data was analyzed using Chi-square test, Mann-Whitney U test and t-test. RESULTS: The expression of p63 (p= 0.009) and maspin (p= 0.012) significantly differed between the study groups. P63 positive cells in MEC were negative for SMA staining in contrast to ADCC. Furthermore, the expression of P63 (p= 0.045) and maspin (p= 0.019) significantly and inversely correlated with histologic grade in ADCC. Likewise, positive significant correlation was detected between histologic grade and expression of P63 (p= 0.018) and MMP-2 (p= 0.003) in MEC samples. CONCLUSION: Our findings showed that MEC is devoid of myoepithelial cells. The difference in expression of P63 and maspin in ADCC and MEC highlighted the role and presence of myoepithelial cells in ADCC. Indeed, the high expression of P63 and maspin in well-differentiated ADCCs suggests the tumor suppressor effect of myoepithelial cells. Considering the association between the evaluated markers and histological grade, p63 in both tumors, maspin in ADCC and MMP-2 in MEC may be efficient predictors of clinical behavior.

Evaluation of VEGF expression correlates with COX-2 expression in pleomorphic adenoma, mucoepidermoid carcinoma and adenoid cystic carcinoma.

BACKGROUND: Pleomorphic adenoma (PA), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (AdCC) are the most common benign and malignant salivary gland tumors. Cyclooxygenase-2 (COX-2) is a key regulatory enzyme that its overexpression in various tumors is correlated with progression, metastasis, and apoptosis inhibition. Vascular endothelial growth factor (VEGF) is a potent angiogenic mediator that has an important role in neoplastic angiogenesis. The aim of this study was to immunohistochemically analyze the expression of COX-2 and VEGF and to compare the expression of benign and two malignant salivary gland tumors with varied structures. MATERIALS AND METHODS: In this cross-sectional study, 90 specimens including 30 cases of each tumor were retrieved. Immunohistochemical staining of COX-2 and VEGF was performed for all the samples. The percentage of positive tumor cells and staining intensity was evaluated by two pathologists blindly. Data were analyzed by Chi-square and Gamma test and P < 0.05. RESULTS: A statistically significant difference was noted between the expression and intensity of COX-2 and VEGF in PA, MEC, and AdCC (P < 0.05). A significant correlation was observed between COX-2 and VEGF expression in MEC and AdCC (P < 0.05). However, no significant correlation was found between the expression and intensity of COX-2 and VEGF with histologic grade and lymph node metastasis in MEC and AdCC (P < 0.05). CONCLUSION: High expression of VEGF and COX-2 in malignant tumors compared to PA suggested the role of both markers in malignant transformation. The significant correlation of VEGF expression with COX-2 may represent the role of COX-2 in tumor angiogenesis by modulating VEGF production.

Angiogenesis and Lymphangiogenesis in Salivary Gland Adenoid Cystic Carcinoma and Mucoepidermoid Carcinoma.

BACKGROUND AND PURPOSE: This study aimed to investigate the immunohistochemical expression of CD31 and podoplanin in order to examine angiogenesis and lymphangiogenesis, respectively in common malignant tumors of salivary glands. MATERIALS AND METHODS: Forty formalin-fixed, paraffinated blocks (20 adenoid cystic carcinoma and 20 mucoepidermoid carcinoma blocks) were selected from the medical archives of Amir A'lam Hospital of Tehran, Iran. Sections from the blocks were stained by CD31 and D2-40 markers via immunohistochemistry. Clinical and demographic information was extracted from the patients' records. FINDINGS: There was a significant difference between tumors in terms of intratumoral microvessel density (MVD) (P< 0.001), total MVD (P< 0.001), and intratumoral lymphatic vessel density (LVD) (P= 0.011). In mucoepidermoid carcinoma, intratumoral MVD and LVD were greater than peritumoral MVD and LVD (P= 0.001 and P< 0.001, respectively). In mucoepidermoid carcinoma, there was no relationship between histological grade with MVD (total, intratumoral or peritumoral) or LVD (total, intratumoral or peritumoral) (P> 0.05). A similar finding was reported with respect to the histopathological grade of adenoid cystic carcinoma (P> 0.05). CONCLUSION: The higher level of angiogenesis and lymphangiogenesis in mucoepidermoid carcinoma, specifically at the center of tumor, compared to adenoid cystic carcinoma, may be attributed to differences in the clinical behaviors and metastasis of tumors. Moreover, considering the high LVD at the center of tumor in mucoepidermoid carcinoma and infrequency of metastasis to regional lymph nodes in adenoid cystic carcinoma, it can play a significant role in metastasis to regional lymph nodes.

Carcinoma-associated Fibroblasts are a Common Finding in the Microenvironment of HPV-positive Oropharyngeal Squamous Cell Carcinoma.

The important role of the human papillomavirus (HPV) is widely established in oropharyngeal squamous cell carcinoma (OPSCC). The behavior of a OPSCCs especially induced by HPV might be influenced by the tissue microenvironment and its changes according to the tumor nature. Recognition of the role of the tumor microenvironment on the behavior of neoplastic cells has led to utilization of the microenvironment to use as therapeutic target. Carcinoma-associated fibroblasts (CAFs), the most abundant cells in the tumor microenvironment, show wide-spread expression of alpha-smooth muscle actin (α-SMA). We focused on CAFs, its presence in OPSCC and the relationship with HPV for the first time. Expression of α-SMA protein in CAFs of the tumor microenvironment of the 44 formalin-fixed paraffin-embedded tissue blocks from the primary tumor of OPSCC evaluated by immunohistochemistry between HPV-positive and HPV-negative tumors separated by nested polymerase chain reaction. In 44 samples 23 HPV-positive cases were detected. Statistically there were significant differences between histopathologic grade, percent and final score of α-SMA and HPV expression. Significant difference between HPV expression and inflammation, intensity, and clinical parameters was not identified in the present study. Our results indicate that CAFs are a common finding in the microenvironment of HPV-positive OPSCC and associated with higher histopathologic grade. Therapeutic strategies to use CAF-mediated drugs need to be considered and evaluated more for treatment of HPV-positive OPSCC.

CD44 expression in pleomorphic adenoma, carcinoma ex pleomorphic adenoma and their adjacent normal salivary glands.

BACKGROUND: CD44 is a transmembranous proteoglycan, with a main role of cell adhesion to other cells and to extracellular matrix involved in the preservation of three-dimensional structure of organs. Pleomorphic adenoma (PA) is a common benign salivary gland tumor, composed of myoepithelial and ductal components. Carcinoma ex-PA (CXPA) is malignant transformation of the epithelial elements in PA. The aim of this study was to evaluate CD44 expression by immunohistochemistry in these two tumors and normal salivary gland near these tumors. MATERIALS AND METHODS: In this cross-sectional immunohistochemical study, 40 paraffin blocks (formalin fixed, paraffin embedded) with thirty belonging to PA and ten blocks of CXPA and 18 paraffinized blocks of normal salivary glands' tissue adjacent to tumoral tissue (13 in the vicinity of PA and 5 in the vicinity of CXPA) were selected. Immunohistochemical expression of CD44 was observed and compared with each other. For data analysis, we used Chi-square, Kruskal-Wallis, and Mann-Whitney tests and the quantity of P values was considered 0.05. RESULTS: There was a significant difference in CD44 expression frequency between PA, CXPA, and normal salivary glands with higher expression noted in CXPA. Furthermore, expression frequency of CD44 in adjacent normal salivary gland of CXPA was significantly higher than PA. There was no significant difference in the expression of CD44 with respect to lymph node metastasis. CONCLUSION: Higher expression of CD44 in CXPA might illustrate CD44's role in malignant transformation of PA.

Evaluation of the Correlation between CD44, Tumor Prognosis and the 5-Year Survival Rate in Patients with Oral Tongue SCC.

INTRODUCTION: 90% of the tumors in the head and neck are squamous-cell carcinomas (HNSCC), which have overall 5- year survival rate between 50% -60%. CD44 has been shown to be associated with the prognosis. MATERIALS AND METHODS: Biopsy specimens of 51 patients with oral tongue SCC were evaluated by Immunohistochemistry (IHC) for the CD44 antibody. RESULTS: There was no significant correlation between CD44 and survival (P=0.77), age (P=0.4), CD44 and lymph node metastasis (P=0.87), sex (P=0.947), smoking (P=0.287) and tumor size (P=0.813). However, there was significant correlation between smoking and survival. CONCLUSION: There are widespread discrepancies among the findings in the literature regarding the prognosis of CD44 expression in OCSCC. Our study shows that the expression of CD44 is not a marker of aggressive behavior in oral tongue SCC. Consequently, CD44 cannot be considered as handy tool to establish the tumor behavior, prognosis and 5- year survival rate of these tumors.

Human endometrial stem cells as a new source for programming to neural cells.

Human EnSC (endometrial-derived stem cell) is an abundant and easily available source for cell replacement therapy. Many investigations have shown the potency of the cells to differentiate into several mesoderm-derived cell lineages, including osteocytes and adipocytes. Here, the potency of EnSC in neural differentiation has been investigated. Flow cytometric analysis showed that they were positive for CD90, CD105, OCT4, CD44 and negative for CD31, CD34, CD133. The characterized cells were induced into neural differentiation by bFGF (basic fibroblast growth factor), PDGF (platelet-derived growth factor) and EGF (epidermal growth factor) signalling molecules, respectively in a sequential protocol, and differentiated cells were analysed for expression of neuronal markers by RT-PCR (reverse transcription-PCR) and immunocytochemistry, including Nestin, GABA (γ-aminobutyric acid), MAP2 (microtubule-associated protein 2), ß3-tub (class III ß-tubulin) and NF-L (neurofilament-light) at the level of their mRNAs. The expression of MAP2, ß3-tub and NF-L proteins in EnSC was confirmed 28 days PT (post-treatment) by immunocytochemistry. In conclusion, EnSC can respond to signalling molecules that are usually used as standards in neural differentiation and can programme neuronal cells, making these cells worth considering as a unique source for cell therapy in neurodegenerative disease.

Minimal Inhibitory Concentration of Ceftazidime and Co-trimoxazole for Stenotrophomonas Maltophilia using E-test.

BACKGROUND: Stenotrophomonas maltophilia, previously named as Pseudomonas or Xanthomonas maltophilia, is an important nosocomial pathogen AIM: The purpose of the present study was to investigate the prevalence of S. maltophilia in Iranian hospitals and its susceptibility to available antimicrobial agents. SETTING AND DESIGN: A cross-sectional study in Imam Khomeini Hospital affiliated to Tehran University of Medical Sciences. MATERIALS AND METHODS: All blood specimens were sent to the laboratory for blood culture and biochemical analysis. One hundred samples were positive for S. maltophilia. We used disk diffusion and E-test in order to determine minimal inhibitory concentration (MIC) of ceftazidime and co-trimoxazole as the first line antibiotics for S. maltophilia. The tests were performed and interpreted according to the guidelines of Clinical Laboratory Standards Institute (CLSI). STATISTICAL ANALYSIS: Chi-square test and Kappa measurement of agreement were applied as appropriate. RESULTS: S. maltophilia was the most frequent pathogen (895 specimens; 38.9%) isolated from the samples which were mostly from emergency ward (780 specimens; 33.9%). Ceftazidime MIC(50) and MIC(90) were 2 and 32 µg/ml, respectively (sensitive ≤8 µg/ml and resistant ≥32 µg/ml according to CLSI guideline). MIC(50) and MIC(90) for co-trimoxazole were 0.5 and 2 µg/ml, respectively (sensitive ≤2 µg/ml and resistant ≥4 µg/ml according to CLSI guideline). CONCLUSION: S. maltophilia is the most frequent pathogen in our hospital with a high susceptibility to both ceftazidime and co-trimoxazole.