Molecular Characterization, Virulence Determinants, and Antimicrobial Resistance Profile of Methicillin-Resistant Staphylococcus aureus in the North of Iran; a High Prevalence of ST239-SCCmec III/t037 Clone

OBJECTIVES

Emergence and prevalence of methicillin-resistant Staphylococcus aureus (MRSA) have become a major universal health concern, limiting therapeutic options.

METHODS

A total number of 37 MRSA isolates, including 19 clinical isolates from hospitalized patients and 18 colonizing isolates from health care workers were identified from 3 hospitals, in Gorgan, North of Iran. Antimicrobial susceptibility test was performed using the disk diffusion method and E-test. The presence of virulence and antibiotic resistance determinants were evaluated by PCR. The genotypical characterization was further analyzed using multi-locus sequence, spa, staphylococcal cassette chromosome, mec (SCCmec), and agr typing.

RESULTS

The frequency of MRSA among S. aureus isolates was 38.14% (37/97). The most frequent S. aureus resistant isolates were found to be obstinate against penicillin (98%) and gentamicin (82.5%). Additionally, the lowest resistance rates were found against daptomycin (0%), vancomycin (2.7%), and quinupristin-dalfopristin (5.4%). All MRSA isolates were susceptible to daptomycin with minimum inhibitory concentration (MIC)50/MIC90 of 0.25/0.5 μg/mL. One isolate belonging to sequence type 239 (ST239)-SCCmecIII/t037 clone (MIC ≥16 μg/mL) was resistant to vancomycin. All but 1 isolate that shares ST22-SCCmec IV/t790 strain were positive for both tsst and pvl genes. The most predominant MRSA isolates (27%) were associated with ST239-SCCmec III/t037, and ST239-SCCmec III/t924 (16.2%) clones, subsequently. In our study, circulating MRSA strains were genetically diverse with a high prevalence of ST239-SCCmec III/t037 clone.

CONCLUSION

These findings emphasize the need for future and continuous surveillance studies on MRSA to prevent the dissemination of existing multidrug resistance MRSA clones in an effective manner.

1211 An Ameloblastoma Or Intra-Oral Basal Cell Carcinoma? A Clinical Case Report

A basal cell ameloblastoma is an uncommon benign neoplasm and has a similar histological appearance to basal cell carcinoma of the skin. This clinical case report will discuss an ameloblastoma originating in the maxilla and of the baseloid variant. The objective of report is to highlight the possibility of misdiagnosis from this challenging case.

A 34-year-old male was referred to the maxillofacial department with recurrent nasal regurgitation following dental extraction from the left maxilla 1 year previous. Clinically there was an oro-antral fistula visible and initial CT showed cystic lesion in the left maxilla likely to represent an odontogenic cyst. The patient underwent extraction and enucleation, where the diagnosis of the amelobalstoma was established with need of resection. Partial maxillectomy and primary closure with buccal fadpad was performed in the second stage and histological results showed a 6mm completely excised basal cell carcinoma within the oral mucosa and no bony invasion. Due to this extremely unusual results, secondary histological review was requested, and conclusion was a fully excised basal cell ameloblastoma. Following the procedure and subsequent reviews, the patient has no evidence of oro-antral fistula or recurrence of this rare type of neoplasm.

A basal cell ameloblastoma variant is a rare lesion and due to its’ similar histological appearance to a basal cell carcinoma, can lead to a misdiagnosis. The aim of the report is to show the unusual presentation and findings along the way to correct diagnosis in this case.

1247 Fusobacterium Necrophorum - A Rare Thyroglossal Cyst Habitat That Can Be Lethal

Thyroglossal cyst is the most frequent developmental cervical anomaly with a prevalence of 7% in the population. Infection and abscess formation are common complications. Isolation of Fusobacterium Necrophorum (F. Necrophorum) made the management of this case challenging.

An 18-year-old male presented to the emergency department with a 3-day history of a neck mass, sore throat, cachexia, dysphagia and fever. Clinical examination revealed an erythematous 4 x 5 fluctuant swelling in the midline of the neck with evident lymphadenopathy on level II on the left-hand side. A CT neck that was undertaken nine months ago was suggestive of a thyroglossal cyst and the patient was placed in the waiting list for surgical excision under general anaesthesia. He reported three episodes of midline neck swelling since then.

Upon admission, ultrasound guided drainage was arranged, and a pus sample obtained. The presence of F. Necrophorum was reported by microbiology with instructions of urgent admission and strict antibiotic regime. Excision of the cyst was scheduled after the completion of the antibiotic course.

Fusobacterium Necrophorum is a rare microorganism with increased virulence and a significant mortality rate. It has been involved in oropharyngeal infections complicated by Lemierre’s syndrome, necrobacillosis, post anginal sepsis and septic jugular thrombophlebitis making this case of particular interest.

Effect of Oral Care Protocol on Dental and Gingival Plaque Index in Patients With Endotracheal Tube Admitted to the Intensive Care Unit

Oral health is one of the most critical aspects of nursing care in critically ill patients. The study aimed to investigate the effect of oral health protocol on dental and gingival plaque index in patients with endotracheal tubes admitted into the ICU. This double-blind clinical trial was conducted on 70 patients admitted into ICU randomly by tossing a coin, and 35 patients were assigned to each of the experimental and control groups. Oral care was performed in the experimental group using the chlorhexidine (CHX) solution, toothpaste, and oral moisturizer protocol; in the control group, according to the routine method, 0.2% CHX was used twice a day. The data were collected at the time of inclusion and four days later, using the MGI and the O'Leary dental plaque index. The mean ages in the experimental and control groups were 38.4±14.4 and 41±14.5 years, respectively. In the experimental and control groups, 77% and 83% of the subjects were male, respectively. After the intervention, the mean gingival index in the experimental and control groups was 0.59±0.31 and 0.90±0.41, and the plaque index was 42.53±15.97 and 53.52±11.9, respectively. The differences before and after the intervention in each group and the difference between the two groups in both gingival and dental plaque indices were statistically significant (P=0.0001). The results showed that the oral health protocol was more effective in improving gingival and dental plaque indices than the routine (CHX) method.

Association between blood groups and COVID-19 outcome in Iranian patients

Aim: Many factors have been speculated to explain the COVID-19 complex clinical phenotype. Due to the inconsistent data published on blood groups and COVID-19, we conducted a study on Iranian patients to further assess this association. Materials & methods: This retrospective study was conducted on data collected from confirmed COVID-19 hospitalized patients during March and December 2020 in a referral hospital for COVID-19, 5 Azar Hospital, Gorgan, north of Iran. A total of 1554 confirmed COVID-19 cases were enrolled in the study with blood group (ABO and Rh), demographic, and clinical data available. Results: Of 1554 patients, 1267 and 287 cases had recovered and deceased (due to COVID-19) outcomes, respectively. Most of the cases had O+ (29.6%), the least number had AB- (0.5%), and most of the deceased cases had O+ blood types (31.4%). Logistic regression analysis revealed that groups A- and B- had higher and groups B+, AB+, O+ and O- had lower odds of death than the A+ group. Conclusion: This study indicates that blood types may be related to the clinical outcome of COVID-19. Further studies with a large cohort for multiple people are required to validate this association.

The potential use of theranostic bacteria in cancer

Conventional chemotherapy approaches have not been fully successful in the treatment of cancer, due to limitations imposed by the pathophysiology of solid tumors, leading to nonspecific drug uptake by healthy cells, poor bioavailability, and toxicity. Thus, novel therapeutic modalities for more efficient cancer treatment are urgently required. Living bacteria can be used as a theranostic approach for the simultaneous diagnosis and therapy of tumors. Herein, we summarize the currently available literature focused on the advantages and challenges for the use of theranostic bacteria in cancer therapy.

Evaluation of Arylsulfatase D (ARSD) and long noncoding RNA ARSD-AS1 gene expression in breast cancer patients and their association with oncogenic transcription factors

PURPOSE

Long non-coding RNAs (LncRNAs) are thought as tumorigenic factors in cancer progression. We investigated the clinical significance of arylsulfatase D (ARSD) and ARSD antisense in breast cancer patients.

METHODS

Eighty breast cancer tumors were obtained from the Tumor Bank of Cancer Institute, Imam Khomeini Hospital. The expression level of ARSD and ARSD-AS1 were examined in breast tumors in comparison to the margin of normal tissues using quantitative real-time PCR. Demographic information and the clinicopathologic characteristics including tumor grade, presence of cell receptors, lymph node and vascular invasion were also evaluated. Bioinformatics databases were used for identification of ARSD and ARSD-AS1 molecular targets and their association with cancer.

RESULTS

Significant up-regulation of ARSD was observed in tumor tissues in comparison with its antisense (p<0.05). Both ARSD and ARSD-AS1 expression in tumor specimens were notably lower than those in adjacent normal tissue. High expression of ARSD was associated to lower tumor grade (p<0.05). Bioinformatics results revealed the interaction of ARSD with STS and SUMF1 proteins was attributed to the inhibiting of sulfates activity. Also, ARSD co-expressed genes were associated with oncogenic transcription factors, MAF and GATA. TP53 transcription factor site was identified as a target of ARSD-AS1 mRNA. The interaction of this antisense with microRNA (miR-618) could explain its participation in tumor cell proliferation.

CONCLUSION

Low expression of ARSD was associated with higher tumor grade. The evidence from this study enhance our understanding of ARSD and ARSD-AS1 function in cancer gene therapy. Accordingly, they could be introduced as great potential targets for breast cancer treatment.