Serotype distribution and antimicrobial susceptibility of invasive Streptococcus pneumoniae isolates among adult and elderly population before and after introduction of pneumococcal conjugate vaccine in Casablanca, Morocco.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae), remains a major cause of mortality and morbidity worldwide. The objective of this study was to determine the trends of invasive pneumococcal diseases (IPD) in adult and elderly population in Casablanca (Morocco) before and after introduction of pneumococcal conjugate vaccine (PCV) by determining the distribution of pneumococcal serotypes and antibiotic resistance profile of isolated strains. METHOD: The proposed study is a retrospective laboratory-based surveillance of IPD in hospitalized adult (15-59 years old) and elderly (≥ 60 years old) patients in Ibn Rochd University Hospital Centre from 2007 to 2019 (13 years). All the 250 non-duplicate clinical invasive isolates from adult and elderly patients, confirmed as S. pneumoniae according to the laboratory standard identification procedures, are included in this study. RESULTS: A significant decrease of the overall incidence in IPD was observed only in adults from 0.71 to 0.54/100000 populations (P = 0.02) and to 0.47/100000 populations (P = 0.0137) in the early and mature post-vaccine period respectively compared to the pre-vaccine period. Our results also showed a significant reduction in the overall prevalence of vaccine serotypes from 28.17 to 6.90% (P = 0.0021) for the PCV-10 serotypes, and from 46.48 to 25.86% (P = 0.0164) for the PCV-13 serotypes only in the mature post-vaccine period (2015-2019). In parallel, the rate of non-vaccine serotypes did not significantly change in the early post-vaccine period (2011-2014) while it increased considerably from 54 to 74.14% (P = 0.0189) during the mature post-vaccine period. The rate of penicillin non-susceptible pneumococcal isolates decreased significantly from 23.94 to 8.77% (P = 0.02) in adult patients, and the rate of cotrimoxazole non-susceptible pneumococcal isolates significantly decreased from 29.58 to 8.77% in the early post-vaccine period (P = 0.003) and to 7.24% in the mature post-vaccine period (P = 0.0007). CONCLUSION: Although childhood vaccination has considerably reduced the incidence of IPD in adult population through the herd effect, IPD remain a real public health problem due to the alarming increase in non-vaccine serotypes (NVS) and the lack of herd effect among elderly population. The rate of antibiotic resistance was relatively low. Nevertheless, resistance constitutes a serious problem to the therapeutic arsenal due to the known capacity for genetic dissemination in the pneumococcus.

Whole genomic comparative analysis of Streptococcus pneumoniae serotype 1 isolates causing invasive and non-invasive infections among children under 5 years in Casablanca, Morocco.

BACKGROUND: Streptococcus pneumoniae serotype 1 remains a leading cause of invasive pneumococcal diseases, even in countries with PCV-10/PCV-13 vaccine implementation. The main objective of this study, which is part of the Pneumococcal African Genome project (PAGe), was to determine the phylogenetic relationships of serotype 1 isolates recovered from children patients in Casablanca (Morocco), compared to these from other African countries; and to investigate the contribution of accessory genes and recombination events to the genetic diversity of this serotype. RESULTS: The genome average size of the six-pneumococcus serotype 1 from Casablanca was 2,227,119 bp, and the average content of coding sequences was 2113, ranging from 2041 to 2161. Pangenome analysis of the 80 genomes used in this study revealed 1685 core genes and 1805 accessory genes. The phylogenetic tree based on core genes and the hierarchical bayesian clustering analysis revealed five sublineages with a phylogeographic structure by country. The Moroccan strains cluster in two different lineages, the five invasive strains clusters altogether in a divergent clade distantly related to the non-invasive strain, that cluster with all the serotype 1 genomes from Africa. CONCLUSIONS: The whole genome sequencing provides increased resolution analysis of the highly virulent serotype 1 in Casablanca, Morocco. Our results are concordant with previous works, showing that the phylogeography of S. pneumoniae serotype 1 is structured by country, and despite the small size (six isolates) of the Moroccan sample, our analysis shows the genetic cohesion of the Moroccan invasive isolates.

Prevalence of multidrug-resistant and extensively drug-resistant phenotypes of Gram-negative bacilli isolated in clinical specimens at Centre Hospitalo-Universitaire Ibn Rochd, Morocco.

Introduction: antimicrobial resistance in gram-negative bacilli is one of the major concerns in public health. We aimed to evaluate gram-negative bacilli epidemiology, antimicrobial profiles, and the resistance´s mechanism for Enterobacteriaceae isolated from specimens of hospitalized patients in wards of University Hospital Center Ibn Rochd of Casablanca, Morocco. Methods: a prospective study of the patient's specimens, collected from December 2016 to 31st March 2017. Isolation and identification were performed using conventional biochemical tests. According to the European Committee on Antimicrobial Susceptibility Testing guidelines, antibiotic susceptibility was determined. Polymerase Chain Reaction (PCR) was used to detect ß-lactamase and carabapenemase genes: CTX-M, SHV, TEM, OXA-48, NDM, and VIM among the Enterobacteriaceae. Results: according to inclusion criteria, 38 Enterobacteriaceae, 25 Acinetobacter baumannii (A. baumannii), and 10 Pseudomonas aeruginosa (P. aeruginosa) were included during the study period; these bacteria were mainly responsible for bacteremia. Fifty-five percent of enterobacteria were extended-spectrum ß-lactamase (ESBL), 42% EBSL and carbapenemase, and 3% carbapenemase, with high coresistances. Eighty-four percent of A. baumannii were XDR. All P. aeruginosa were MDR; amikacin showed the best activity (70% susceptibility). The genotypic approach revealed the presence of blaCTX-M, blaSHV, blaTEM in 68%, 22%, and 11% respectively. Of the 22 carbapenemase-producers, 41% were blaOXA-48 and 18% blaNDM; none had blaVIM. Furthermore, various genes coexistence were detected: blaCTX-M+blaOXA-48; blaCTX-M+blaNDM; blaCTX-M+blaSHV+blaOXA-48; and blaSHV+blaOXA-48. Conclusion: findings revealed highly resistance rate among isolates. This raises the need to control antibiotics and regular screening to identify dynamics promoting resistance. Thus, we recommend developing antimicrobial stewardship programs and improving hygiene systems to prevent the nosocomial spreading of these phenotypes in our center.

Evaluation of the Performances of the Rapid Test RESIST-5 O.O.K.N.V Used for the Detection of Carbapenemases-Producing Enterobacterales.

BACKGROUND: The emergence of carbapenemase-producing Enterobacterales (CPE) is a public health problem, requiring rapid and reliable diagnostic methods. The aim is to compare the new rapid immunochromatographic (IC) test: RESIST-5 O.O.K.N.V with PCR and the predictive model of EUCAST algorithm for the detection of CPE. METHODS: A longitudinal cross-sectional study was carried out in the bacteriology-virology laboratory of the Ibn Rochd-Casablanca University Hospital, from 1 February 2019 to 28 February 2020, concerning strains with reduced sensitivity to Ertapenem. The identification of bacterial species was carried out according to the standard criteria of microbiology and antibiogram according to CASFM-EUCAST 2019 recommendations. The sensitivity and specificity of the rapid IC test were calculated. RESULTS: The results of the new IC test showed a sensitivity and specificity of 100% for the detection of OXA-48 and NDM. These carbapenemases were detected simultaneously with a sensitivity and specificity of 100%. OXA-48 was the most common carbapenemas found (36%), followed by NDM (24%) and (13.4%) cases of OXA-48 and NDM coexistence. CONCLUSION: The rapid IC test could be a rapid and effective diagnostic tool for detecting the most common carbapenemases in our context, and to accelerate the implementation of adequate antibiotic therapy and infection control measures in patients with CPE infections.

Early neonatal respiratory distress revealing meningitis caused by Streptococcus pneumoniae serotype 17F: a case report.

Background: Streptococcus pneumoniae (S. pneumoniae) is the first leading cause of invasive diseases such as meningitis, bacteremia and pneumoniae in children. In this case we report an early neonatal respiratory distress revealing meningitis caused by S. pneumoniae Serotype 17F through vertical transmission, in the newborn of 3 hours of live. Case description: A male late preterm newborn was born by vaginal delivery at a gestational age of 34 weeks. At 3 hours of life, he was admitted for early moderate neonatal respiratory distress in the Neonatal Medicine and Resuscitation Service. Cerebrospinal fluid culture yielded S. pneumoniae belonging to serotype 17F while the blood culture was negative. The same pneumococcal serotype was recovered from the high vaginal swab of the mother. Both isolates were found susceptible to all tested antibiotics except tetracycline and chloramphenicol to which the strain was resistant. Antibiotherapy management of the child included ceftriaxone at 150mg/kg/day for 21 days, in combination with gentamycin at 5 mg/kg/day for 5 days. ciprofloxacin was added at 40mg/kg/day in two doses for a period of three weeks as the baby presented a hydrocephalus. Conclusion: This finding shows that clinical manifestations of neonatal pneumococcal meningitis may be atypical and/or misleading.

Surgical wound infection caused by a multi drug resistant Streptococcus pneumoniae Serotype 19A after a total coloproctectomy with ileostomy.

Streptococcus pneumoniae (S. pneumoniae) colonizes asymptomatically the human nasopharynx. This pathogen is responsible for sinusitis, otitis media, pneumonia, bacteremia and meningitis. We report the case of a 35-year-old female patient who developed a surgical wound infection by a multi drug resistant S. pneumoniae serotype 19A after a total coloprotectomy. This first found in Morocco shows the implication of multidrug resistant S. pneumoniae in surgical wound infections.

Epidemiological profile of Neisseria meningitidis in Casablanca, Morocco: 2010-2019.

Surveillance of invasive meningococcal diseases (IMD) must be carried out regularly and continuously in order to detect the emergence of strains of reduced susceptibility to antibiotics for therapeutic and prophylactic use and the appearance of new invasive clones. Molecular-typing approaches allow reliable traceability and powerful epidemiological analysis. This is an epidemiological study of Neisseria meningitidis causing meningitis in Casablanca, Morocco. The grouping was confirmed by PCR mainly on the isolates from cerebrospinal fluid (CSF). A total of 245 confirmed isolates of N .meningitidis were obtained between 2010 and 2019 of which 93 % are of group B. Overall, 24 % of all the isolates have a reduced susceptibility to penicillin G, but no resistance to penicillin G has been reported. All the isolated strains are susceptible to third-generation cephalosporins (3GCs). Genotyping by multilocus sequence typing (MLST) of a selection of 18 strains showed that the majority of isolates belong to the invasive clonal complex CC 32(9/18) followed by the CC 41/44(3/18).

[Meningitis caused by Streptococcus pneumoniae serotype 7a in an infant vaccinated with two doses of 13-valent pneumococcal conjugate vaccine: a case study]. / Méningite à Streptococcus pneumoniae sérotype 7A chez un nourrisson immunisé par deux doses du vaccin pneumococcique conjugué 13-valent: à propos d'un cas.

Pneumococcal meningitis is a global scourge. It is a major cause of morbidity and mortality. In Morocco, 13-valent pneumococcal conjugate vaccine (PCV13) was introduced into the National Immunization Program in October 2010 according to the immunization schedule 2 + 1 and replaced by PCV10 in July 2012, according to the same schedule. Despite the use of the PCV13, which is essential in the fight against pneumococcal disease, the emergence of new non-vaccine serotypes always results in meningitis in children, causing serious sequelae. We report the case of an infant vaccinated with two doses of PCV13 with meningitis caused by Streptococcus pneumoniae serotype 7a. The peculiarity of this case study lies in pneumococcal meningitis due to Streptococcus pneumoniae serotype 7a not included in the PCV13 in an infant immunized by 2 doses of PCV13. We here insist on the need and the importance of an observatory for pneumococcal meningitis and of a wide epidemiological study in order to determine the serotypes in Morocco after the introduction of PCV13 and then of PCV10.

[HIV co-infection in patients followed up for tuberculosis in the Division of Infectious Diseases at the Ibn Rochd University Hospital in Casablanca]. / Co-infection VIH chez les tuberculeux suivis au service des maladies infectieuses du CHU Ibn Rochd-Casablanca.

This study aims to determine the prevalence of HIV infection among patients hospitalized for tuberculosis in the Division of Infectious Diseases at the Ibn Rochd University Hospital in Casablanca and factors associated with TB-HIV co-infection. We conducted a cross-sectional retrospective study in November 2016. The database of the Division of Infectious Diseases, Laboratory of Microbiology and Immunology at the Ibn Rochd University Hospital was examined. All the patients with tuberculosis confirmed using Lowenstein Jensen culture medium and HIV Infection confirmed using Western Blot test between January 2013 and December 2015 were included. During the study period, 117 cases of tuberculosis were confirmed by culture. Fourty six (39.3%) patients had confirmed HIV infection. Thirty-four co-infected patients (73.9%) had extrapulmonary tuberculosis (this form was associated with co-infection (p=0.04)). All patients underwent TB treatment and anti-retroviral treatment according to the indication. The Evolution was favorable in 32 patients (69.6%) and 10 deaths were recorded (21.7%). Mortality rate was higher in co-infected patients than in TB patients without HIV (8.4%), (p=0.04). This study highlights a relatively high prevalence of HIV infection among tuberculosis patients. TB-HIV co-infection is associated with severe forms of tuberculosis and with an increase in mortality rate among TB patients; hence the importance of strengthening anti-co-infection joint activities.

Prevalence of Acinetobacter baumannii bacteremia in intensive care units of Ibn Rochd University Hospital, Casablanca.

BACKGROUND AND OBJECTIVES: Acinetobacter baumannii bacteremia are grave because of the multi-resistance of the organism to antibiotics. This study aimed to determine the prevalence of A. baumannii isolated from blood cultures and to describe their antibiotic resistance patterns. MATERIALS AND METHODS: A retrospective longitudinal study was conducted on blood cultures between 2010 and 2014 from all Ibn Rochd University Hospital intensive care units; it was based on the exploitation of microbiology laboratory database (duplicates were excluded). Isolation and identification of A. baumannii were performed according to standard techniques of bacteriology and susceptibility testing as recommended by the CLSI. PCR was used to detect ß-Lactamase genes, blaOXA-51, blaOXA-23. RESULTS: Among the 4232 samples received at the laboratory, 2402 (56.8%) were positive. Negative coagulase Staphylococcus was isolated in 21.6% of cases followed by A. baumannii (9.2%), and K. pneumoniae (9.1%). A. baumannii strains were resistant to most antibiotics tested: imipenem (75.7%), ceftazidim (85.4%), cefotaxim (98.6%), gentamicin (78.1%), amikacin (63.5%) and ciprofloxacin (88.2%). All A. baumannii strains, resistant to carbapenem, tested were positive for blaOXA-51 genes and 87.5% expressed the blaOXA-23 genes. CONCLUSION: A. baumannii was the second germ frequently isolated from blood cultures in intensive care units. It was multi-resistant to antibiotics. The strengthening of hospital hygiene measures and surveillance of antibiotic resistance is needed to limit the spread of germs and to optimize the management of antibiotics.