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.
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.
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).
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.
Highlights • Streptococcus pneumoniae is a major causative agent of morbidity and mortality among young children. • In October 2010, the 13-valent pneumococcal conjugate vaccine (PCV-13) was ...introduced in the Moroccan National Immunization Program and replaced by the PCV-10 in July 2012. • We report the impact of pneumococcal conjugate vaccine on invasive pneumococcal disease in children under five in Morocco before and the pneumococcal vaccine implementation. • As expected, the incidence rate of IPD associated with vaccine serotype declined after vaccine implementation. The observed decline was only significant in children ≤2 years. In fact, following the introduction of PCVs in Casablanca, the incidence rate of IPD declined from 34.6 to 13.5/ 100,000 populations with a reduction of 61%. A significant reduction of penicillin and cotrimoxazole non-susceptible strains occurred in the same age.
In recent decades, there has been a marked increase in the number of reported cases of pertussis around the world, and pertussis continues to be a frequently occurring disease despite an effective ...childhood vaccination. This study aims to determine the role of household contacts of children diagnosed with pertussis in Casablanca Morocco.
From November 2015 to October 2017, children suspected of whooping cough that consulted Ibn Rochd University hospital at Casablanca with their household contacts were enrolled in the study. Nasopharyngeal (NP) samples of the suspected children were analyzed by culture and RT-PCR. For the household contacts, NP and blood samples were collected and analyzed by RT-PCR and specific detection of pertussis toxin antibodies by ELISA, respectively.
During the study period, the survey was carried out on 128 infants hospitalized for pertussis suspicion and their families (N = 140). B. pertussis DNA was specifically detected in 73 (57%) samples, coexistence of B. pertussis and B. parapertussis DNA in 3 (2.3%) samples, coexistence of B. pertussis and B. holmesii DNA in 10 (7.81%) and only one (0.78%) sample was IS 481 RT-PCR positive without the possibility of determining the Bordetella species with the diagnostic tools used. Confirmations of Pertussis infection in household contacts by culture, RT- PCR and serology were 10, 46 and 39%, respectively. B. pertussis DNA was confirmed in the infants as well in their mothers in 38% of the cases. Co detection of B. pertussis and B. parapertussis DNA in 2% and co-detection of B. pertussis and B. holmesii DNA in 4%. B. holmesii DNA alone was detected in 5 NP samples of index cases and their mothers.
The results of this study confirm that B. pertussis is still circulating in children and adults, and were likely a source of pertussis contamination in infants still not vaccinated. The use of RT-PCR specific for B. pertussis in the diagnosis of adults is less sensitive and should be associated with serologic tests to improve diagnosis of pertussis and contributes to preventing transmission of the disease in infants.
Pertussis, a vaccine preventable disease, is still responsible of significant morbidity and mortality around the world, mostly in newborns. The aim of the present study was (1) to introduce pertussis ...surveillance in the major pediatric hospital of Casablanca (2) to analyze the prevalence of pertussis among children under 14 years of age and their entourage in Casablanca, Morocco.
This is a prospective and non-case controlled study, including children suspected of Pertussis admitted at the Abderrahim Harouchi Pediatric Hospital in Casablanca, from January 2013 to June 2015. Nasopharyngeal samples were obtained for Bordetella spp. culture and Real time PCR detection (RT-PCR) with specific primers of Bordetella spp., B. pertussis, B. parapertussis and B. holmesii. The detection of Bordetella spp. was also performed in some household contacts of the children suspected of pertussis.
During the 2.5-years period, a total of 282 samples were collected from hospitalized children (156) and in some of their contacts (126). Among 156 samples from the children (from whom 57% were under 2 month of age), Bordetella DNA was detected in 61% (96/156) by RT-PCR. Among these positive samples, 91.7% (88/96) corresponded to B. pertussis DNA. Furthermore, in 39.5% (38/96) of the Bordetella positive samples, B. holmesii DNA was also detected. B. parapertussis DNA was detected in only one sample (1/156). Out of the 156 samples collected from the hospitalized children, only 48 were tested by culture, and 4 B. pertussis were isolated (8.3%). Among the 126 samples from the contacts of the children, mostly mothers (115 cases), Bordetella DNA was detected in 47% (59/126), 90% (53/59) being B. pertussis DNA. Moreover, B. holmesii DNA was also detected in 18.6% (11/59) of the Bordetella positive samples, and coexistence of B. pertussis and B. holmesii DNA in 36.5% (35/96). Two B. pertussis were isolated by culture performed on 43 samples of the contacts of the children (4.6%).
This study highlights the circulation of B. pertussis but also of B. holmesii in Casablanca-Morocco with a high proportion of co-infections B. holmesii/B. pertussis in infants and their mothers, indicate that infection of non-vaccinated infants could be more associated with young parents. Moreover, the RT- PCR provides a sensitive and specific diagnosis of B. pertussis infections and distinguishes it from other Bordetella species, and is therefore suitable for implementation in the diagnostic laboratory.
This study aimed to investigate the nature of the amino acid motifs found in PBPs of Streptococcus pneumoniae isolates in invasive diseases from pediatric patients at Casablanca, Morocco. Five ...penicillin-susceptible (PSSP), ten penicillin-intermediate (PISP), and fifteen penicillin-resistant S. pneumoniae (PRSP) were studied by PCR-RFLP and DNA sequencing of the pbp1a, - 2b, and - 2x genes.
There were no changes in the conserved motifs of PBP1a, PBP2b and PBP2x for PSSP strains. Substitution close to PBP1a conserved motifs were found in all PRSP isolates and six/five PISP. Analysis of PBP2b showed that all but one of the 10 PISP strains and all PRSP had substitutions. Substitution close to PBP2x motifs showed that all but three of the 10 PISP strains and all PRSP had substitutions in tow conserved motifs. A total of 6, 11 and 10 genotypes were found after analysis of pbp1a, pbp2b, and pbp2x, respectively. The penicillin-nonsusceptible S. pneumoniae isolated in Casablanca share most amino acid substitutions of those reported worldwide, but they occurred among pneumococci with low level resistance to b-lactams.
IntroductionLa réalisation des hémocultures est le meilleur moyen de diagnostic des bactériémies, cependant les résultats faussement positifs peuvent entraîner une confusion concernant les schémas ...thérapeutiques antibiotiques, mettant ainsi en danger la sécurité des patients. L'objectif principal de ce travail est d'évaluer la prévalence des Staphylocoques à coagulase négative (SCN) ainsi que Corynebacterium spp et Bacillus spp dans les ballons d'hémoculture analysés au laboratoire de microbiologie du Centre Hospitalier Universitaire (CHU) Ibn Rochd de Casablanca. Cette prévalence a été aussi évaluée en fonction de différents services hospitaliers sur l'année 2016.MéthodesIl s'agit d'une étude rétrospective descriptive basée sur une analyse de la base de données informatisée du laboratoire de bactériologie-virologie du CHU Ibn Rochd de Casablanca sur une période de 12 mois allant du 1er janvier au 31 décembre 2016, Ont été inclus dans notre étude les bactéries faisant partie de la flore commensale (staphylocoque à coagulase négative,corynébactéries spp et Bacillus spp) Les ballons d'hémoculture ont été incubés sur automate Bactec FX. L'identification des germes à partir d'une culture positive a été réalisée selon les techniques standards de bactériologie et l'antibiogramme selon EUCAST 2015. L'étude est basée sur une analyse de la base de données informatisée du système KALISIL (Netika) version (2.2.10.) du Laboratoire de Microbiologie du CHU Ibn Rochd-Casablanca Maroc.RésultatsSur 7959 demandes d'hémocultures adressées au laboratoire de bactériologie provenant de 5801 patients, 2491 étaient positifs dont 848, soit 34% des ballons positifs ou 10,6% de l'ensemble des ballons reçus durant l'année 2016, ont été représentées par staphylocoque à coagulase négative, 56 soit (2,2%) ballons des hémocultures par corrynébacteruim SP, suivi par 60 soit (2,4%) ballons par bacillus sp. La fréquence d'isolement du SCN par rapport aux autres bactéries en fonction des services cliniques a montré une fréquence plus élevée dans les services de pédiatrie avec 47,2% suivie des services de médecine avec 44,1%.ConclusionCette étude montre que, Les staphylocoques à coagulase négative sont les organismes les plus fréquemment isolés des hémocultures, ils constituent une cause non négligeable d'infections nosocomiales mais, ils sont également les contaminants les plus courants des hémocultures.
the laboratory diagnosis of tuberculosis (TB) relies mainly on conventional techniques. However, it either lacks sensitivity or it is time-consuming. This study aims to evaluate the use of real-time ...polymerase chain reaction (PCR) targeting IS6110 for Mycobacterium tuberculosis (TB) Complex (MTBC) in the routine diagnosis of TB in our laboratory.
clinical samples were collected from the laboratory of bacteriology at Ibn Rochd University Hospital in Casablanca Morocco. Real-time polymerase chain reaction (PCR) results were compared to AFB smear and culture on Löwenstein-Jensen (LJ) solid media. Sensitivity, specificity, positive and negative predictive value (PPV and NPV) with 95% confidence intervals were calculated using GraphPad Prism.
on 171 clinical samples, the study showed positivity of microscopy, culture and real-time PCR for M. TB complex as 19%, 31%, and 32% respectively. Sensitivity, specificity, PPV and NPV for real-time PCR in pulmonary samples were 95.2%, 95.4%, 90.91% and 97.65% respectively. For extra-pulmonary samples, they were: 72.7%, 90.32%, 72.7%, and 90.3%.
our study shows the effectiveness of using real-time PCR IS6110 in pulmonary and extra pulmonary samples. Future multicentric studies could seek to evaluate the place of this technique on routine diagnosis for better management of TB in Morocco.
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
Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, especially among children and the elderly. The ability to effectively treat pneumococcal infection has been compromised ...due to the acquisition of antibiotic resistance, particularly to β-lactam drugs. This study aimed to describe the prevalence and molecular evolution of penicillin non-susceptible S. pneumoniae (PNSP) isolated from invasive diseases before and after pneumococcal conjugate vaccine implementation in Casablanca, Morocco.
Isolates were obtained from the Microbiology Laboratory of Ibn Rochd University Hospital Centre of Casablanca. Serogrouping was done by Pneumotest Kit and serotyping by the Quellung capsular swelling. Antibiotic susceptibility pattern was determined by disk diffusion and E-test methods. The PNSP were analyzed by pulsed-field gel electrophoresis (PFGE) and by genotyping of pbp1a, pbp2b, and pbp2x genes.
A total of 361 S. pneumoniae isolates were collected from 2007 to 2014. Of these isolates, 58.7% were obtained before vaccination (2007-2010) and 41.3% after vaccination (2011-2014). Of the 361 isolates, 80 were PNSP (22.2%). Generally, the proportion of PNSP between pre- and post-vaccination periods were 31 and 13% (p = 0.009), respectively. The proportion of PNSP isolated from pediatric and adult (age > 14 years) patients decreased from 34.5 to 22.9% (p = 0.1) and from 17.7 to 10.2% (p = 0.1) before and after vaccine implementation, respectively. The leading serotypes of PNSP were 14 (33 vs. 57%) and 19A (18 vs. 14%) before and after vaccination among children. For adults, serotypes 19A (53%) and 23F (24%) were the dominant serotypes in the pre-vaccination period, while serotype 14 (22%) was the most prevalent after vaccination. There were 21 pbp genotypes in the pre-vaccination period vs. 12 for post-vaccination period. PFGE clustering showed six clusters of PNSP grouped into three clusters specific to pre-vaccination period (clusters I, II and III), two clusters specific to post-period (clusters V and VI) and a cluster (IV) that contained clones belonging to the two periods of vaccination.
Our observations demonstrate a high degree of genetic diversity among PNSP. Genetic clustering among PNSP strains showed that they spread mainly by a restricted number of PNSP clones with vaccine serotypes. PFGE clustering combined with pbp genotyping revealed that vaccination can change the population structure of PNSP.
Urinary tract infection (UTI) diagnosis by urine culture is time- and labor- consuming. In the Ibn Rochd microbiology laboratory, up to 70% of urine culture samples yield no growth or insignificant ...growth.
To evaluate the new generation of Sysmex UF-4000i fluorescence flow cytometry analyzer with a blue semiconducting laser as a method to rule out negative urine samples for UTI, in comparison of urine culture.
Flow cytometry and microbiological analysis were performed on 502 urine samples included in the study. We used ROC analysis to determine cutoff points at which optimal sensitivity and specificity are achieved for clinical use.
Our results showed that bacteria count at a cut-off of 100/μL, and/or the leucocytes count ≥ 45/μL are the optimal indicator for positive culture results. At these cut off, bacteria sensitivity (SE), specificity (SP), Positive predictive value (PPV) and negative predictive value (NPV) were 97,3%, 95%, 87,8% and 98,8% respectively. For leucocytes, SE, SP, PPV and NPV were 99,1%, 95,8%, 88,6% and 99,7% respectively.
The bacterial and leucocytes counts generated by UF-4000i analysis may be useful in our context as a rapid screening to exclude UTI by reducing about 70% of urines cultures and then workload. Nevertheless, further validation is needed for different patient groups especially with urological disease or immunocompromised patients.
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