Occurrence of carbapenem-resistant hypervirulent Klebsiella pneumoniae in oysters in Egypt: a significant public health issue.

BACKGROUND: The global dissemination of critical-priority carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKp) via food sources represents a significant public health concern. Epidemiological data on CR-hvKp in oysters in Egypt is limited. This study aimed to investigate the potential role of oysters sold in Egypt as a source for carbapenem-resistant K. pneumoniae (CRKP), hypervirulent K. pneumoniae (hvKp), and CR-hvKp and assess associated zoonotic risks. METHODS: A sample of 330 fresh oysters was randomly purchased from various retail fish markets in Egypt and divided into 33 pools. Bacteriological examination and the identification of Klebsiella pneumoniae were performed. Carbapenem resistance in K. pneumoniae isolates was determined by phenotypic and molecular methods. Additionally, the presence of hypervirulent K. pneumoniae was identified based on virulence gene markers (peg-344, rmpA, rmpA2, iucA, and iroB), followed by a string test. The clustering of CR-hvKp strains was carried out using R with the pheatmap package. RESULTS: The overall prevalence of K. pneumoniae was 48.5% (16 out of 33), with 13 isolates displaying carbapenem resistance, one intermediate resistance, and two sensitive. Both carbapenem-resistant K. pneumoniae and carbapenem-intermediate-resistant K. pneumoniae strains exhibited carbapenemase production, predominantly linked to the blaVIM gene (68.8%). HvKp strains were identified at a rate of 62.5% (10/16); notably, peg-344 was the most prevalent gene. Significantly, 10 of the 13 CRKP isolates possessed hypervirulence genes, contributing to the emergence of CR-hvKp. Moreover, cluster analysis revealed the clustering of two CR-hvKp isolates from the same retail fish market. CONCLUSION: This study provides the first insight into the emergence of CR-hvKp among oysters in Egypt. It underscores the potential role of oysters as a source for disseminating CR-hvKp within aquatic ecosystems, presenting a possible threat to public health.

Radiographic Assessment of Three-implant-retained Mandibular Overdentures: A Clinical Study of Alveolar Bone Height Changes (Randomized Clinical Trial).

AIM: To evaluate the residual alveolar ridge bone height changes regarding the impact of the block-out spacer used during the pick-up procedures of implant-assisted mandibular complete overdentures. MATERIALS AND METHODS: This study was a randomized clinical trial conducted on 18 patients. All patients received three mandibular dental implants with definitive locator attachments which were directly picked up with two different techniques. Patients were classified randomly without any bias into two equal groups (Group I block-out spacer) and (Group II without block-out spacer). Over a year, the digital radiographic technique with new technique of reference points was employed to evaluate the changes in the residual alveolar ridge bone heights. The data were statistically analyzed to test the significance difference between groups. RESULTS: Concerning the residual alveolar ridge resorption RRR, group I exhibited a significantly higher RRR than group II. CONCLUSION: In terms of residual alveolar ridge preservation, not using the block-out spacer was more beneficial than using it. CLINICAL SIGNIFICANCE: Alveolar bone heights can be affected by the use of block-out spacer during pick-up procedure within accepted physiologic values. The removal of the block-out spacer could be more beneficial with respect to the preservation of the residual alveolar ridge. How to cite this article: Mohammed REL, Askar OM, El-Waseef FAE, et al. Radiographic Assessment of Three-implant-retained Mandibular Overdentures: A Clinical Study of Alveolar Bone Height Changes (Randomized Clinical Trial). J Contemp Dent Pract 2023;24(11):847-852.

Horse: a potential source of Cryptococcus neoformans and Cryptococcus gattii in Egypt.

BACKGROUND: Cryptococcosis is an opportunistic mycozoonosis of global significance in a wide variety of host species. In equines, cryptococcosis is uncommon, and sporadic cases have been reported with rhinitis, sinusitis, pneumonia, and meningitis. Cryptococcus spp. represents a potential risk for immunosuppressed and healthy persons. In Egypt, epidemiological data on cryptococcal infection in horses are limited. The current study was carried out to investigate the occurrence of Cryptococcus spp. in horses and its possible role in the epidemiology of such disease in Egypt. A total of 223 samples was collected from different localities in Egypt included 183 nasal swabs from horses, 28 nasal swabs from humans, and 12 soil samples. Bacteriological examination and the identification of Cryptococcus spp. were performed. Molecular serotyping of Cryptococcus spp. was determined by multiplex PCR using CNa-70S/A-CNb-49S/A. The virulence genes (LAC1, CAP59, and PLB1) of the identified isolates were detected by PCR. Moreover, sequencing and phylogenetic analysis of the C. gattii gene from horses, humans, and soil isolates found nearby were performed. RESULT: The overall occurrence of Cryptococcus spp. in horses were 9.3, 25, and 10.7% in horses, the soil, and humans, respectively. Molecular serotyping of the Cryptococcus spp. isolates recovered from the nasal passages of horses proved that C. gattii (B), C. neoformans, and two hybrids between C. neoformans (A) and C. gattii (B) were identified. Meanwhile, in case of soil samples, the isolates were identified as C. gattii (B). The human isolates were serotyped as C. gattii in two isolates and C. neoformans in only one isolate. Molecular detection of some virulence genes (LAC1), (CAP59), and (PLB1) were identified in both C. gattii and C. neoformans isolates. The C. gattii gene amplicons of the isolates from horses, humans, and the soil were closely related. CONCLUSION: This study provides the first insights into the Egyptian horse ecology of Cryptococcus species and highlights the role of horses as asymptomatic carriers in disseminating the potentially pathogenic Cryptococcus spp. It also presents the possible risk of cryptococcosis infection in humans.

Corrigendum to "Incidence of Calf Morbidity and Its Predictors in North Shewa, Amhara, Ethiopia".

[This corrects the article DOI: 10.1155/2020/6490710.].