Serotype Prevalence and Penicillin-susceptibility of Streptococcus pneumoniae in Oman

Serotype distribution and antibiotic resistance among invasive Streptococcus pneumoniae from Oman post 13-valent vaccine introduction

OBJECTIVE

This study was undertaken to determine the serotype distribution and drug susceptibility patterns in pneumococcal isolates recovered from patients with invasive pneumococcal disease (IPD).

METHODS

All invasive pneumococcal isolates received between June 2014 and June 2016 were included in the study as part of a national laboratory-based IPD surveillance program. Isolates recovered from clinical specimens of normally sterile body sites were included.

RESULTS

A total of 41 different serotypes were identified among the 132 pneumococcal isolates included in this study. The most prevalent serotypes/serogroups were 12 (8.3%), 15 (8.3%), 19F (7.6%), 3 (6.1%), and 19A (6.1%);. It was observed that overall vaccine coverage rates for pneumococcal conjugate vaccines (PCV), PCV7, PCV10 and PCV13 were 15.9%, 24.2% and 37.1% respectively. 56.8% (n=75) of the isolates were non-susceptible to at least one antibiotic and 40.9% (n=54) of the isolates were resistant to PEN (M). 18.9% (n=25) of the isolates were multi-drug resistant (MDR).The case fatality rate was 15.9%.

CONCLUSION

Our study results call for broader vaccine coverage, emphasizes the need to introduce the conjugate pneumococcal vaccine for the high risk adult population and stress the importance of continuous surveillance of serotypes and antimicrobial resistance to guide vaccine development and antimicrobial stewardship activities.

Trends in Antimicrobial Drug Resistance of Streptococcus pneumoniae Isolates at Jordan University Hospital (2000⁻2018)

Antimicrobial drug resistance (AMR) in pneumococci complicates the treatment of serious pneumococcal infections. Country-specific AMR patterns can help to establish guidelines for empiric therapy. The aim of the current study was to analyze the distribution of AMR among Streptococcus pneumoniae isolates at Jordan University Hospital (JUH) during 2000⁻2018. Paper-based and electronic clinical data registry records from 2000 to 2018 were retrospectively analyzed to study the AMR among pneumococcal isolates at JUH. Temporal trend analysis was done using two-tailed linear-by-linear test for association. The total number of unique pneumococcal isolates that were identified was 556, of which 544 isolates had antimicrobial susceptibility testing results. The most frequent specimens were eye (n = 117, 21.0%), bloodstream (n = 93, 16.7%) and sputum (n = 81, 14.6%). Invasive infections represented 23.6% of all unique isolates. The overall susceptibility of S. pneumoniae isolates during the study period to different antimicrobials was: 100% to vancomycin, 97.7% to ceftriaxone, 97.1% to cefotaxime, 94.9% to chloramphenicol, 89.7% to penicillin, 83.8% to levofloxacin, 67.7% to clindamycin and 52.1% to erythromycin. The prevalence of multi-drug resistance (MDR) was 8.6% (95% confidence interval: 6.4⁻11.5%). Trend analysis showed an increase in the prevalence of non-susceptibility to erythromycin, clindamycin and levofloxacin (p < 0.001). MDR prevalence increased from 1.6% in the first quarter to 14.6% in the fourth quarter (p < 0.001). The incidence of invasive infections declined over the study period (p < 0.001). The increase in the prevalence of AMR and MDR among pneumococcal isolates in Jordan demands judicious use of antimicrobials and regular surveillance of resistance.

Epidemiology of common resistant bacterial pathogens in the countries of the Arab League

No uniformly organised collection of data regarding antimicrobial resistance has occurred in the countries of the Arab League. 19 countries of the Arab League have published data for antimicrobial susceptibility for the WHO priority organisms, and seven of 14 of these organisms are included in this Review (Escherichia coli, Klebsiella spp, Pseudomonas aeruginosa, Acinetobacter baumannii, Salmonella spp, Staphylococcus aureus, and Streptococcus pneumoniae). Although E coli and Klebsiella spp resistance to third-generation cephalosporins is common in all countries, with prevalence reaching more than 50% in Egypt and Syria, carbapenem resistance is emerging, albeit with a prevalence of less than 10%. Conversely, a large amount of carbapenem resistance has been reported for P aeruginosa and A baumannii across the Arab League, reaching 50% and 88% of isolates in some countries. As for Salmonella spp, the prevalence of fluoroquinolone resistance has exceeded 30% in several areas. With regards to the Gram-positive pathogens, the prevalence of meticillin resistance in S aureus is reported to be between 20% and 30% in most countries, but exceeds 60% in Egypt and Iraq. The prevalence of penicillin non-susceptibility among pneumococci has reached more than 20% in Algeria, Egypt, Morocco, Saudi Arabia, and Tunisia. These findings highlight the need for structured national plans in the region to target infection prevention and antimicrobial stewardship.

Intrapancreatic accessory spleen: Evaluation with CT and MRI

The aim of the present study was to evaluate the characteristics of computed tomography (CT) and magnetic resonance imaging (MRI), particularly diffusion-weighted imaging (DWI), in the imaging of intrapancreatic accessory spleen (IPAS). The clinical and pathological records of 9 patients, including 8 patients with IPAS and 1 patient with splenosis, were reviewed. The patients had undergone plain and triple-phase enhanced CT scanning (n=9) and MRI scanning (n=8). The lesions of the 8 IPAS patients were located in the pancreatic tail, and were round (n=3), oval (n=4) or triangular (n=1) in shape. The CT and/or MRI densities, signal intensities and dynamic enhanced patterns of the lesions were similar to those of the orthotopic spleen. In DWI images (n=5), the IPAS regions presented high signal intensity (SI), and no significant difference in the apparent diffusion coefficient determined using a b-value of 600 sec/mm² was identified between the IPAS and orthotopic spleen (P>0.05). One patient with splenosis complicated with cirrhosis had a nodule located in the pancreatic tail with an unenhanced CT value of 65 HU. In MRI examination, with the exception of the dynamic enhancement pattern, the T1-weighted, T2-weighted and DWI signals of splenosis were inconsistent with those of the normal spleen. In conclusion, in pre-contrast and post-contrast-enhanced CT and MRI images, IPAS exhibits similar characteristics to the orthotopic spleen. CT and MRI used in combination with DWI are important in the diagnosis of IPAS.

Using Nanoparticles in Medicine for Liver Cancer Imaging

One of the most important types of liver cancer is hepatocellular carcinoma (HCC). HCC is the fifth most common cancer, and its correct diagnosis is very important. For the quick diagnosis of HCC, the use of nanoparticles is helpful. The major applications of nanoparticles are in medicine for organ imaging. Two methods of liver imaging are X-ray computed tomography (CT) and magnetic resonance imaging (MRI). In this review, we attempt to summarize some of the contrast agents used in imaging such as superparamagnetic iron oxide nanoparticles (SPIONs) and iron oxide nanoparticles (IONPs), various types of enhanced MRI for the liver, and nanoparticles like gold (AuNPs), which is used to develop novel CT imaging agents.

Incidence and economic burden of acute otitis media in children aged up to 5years in three Middle Eastern countries and Pakistan: A multinational, retrospective, observational study

Epidemiological data on acute otitis media (AOM), an infectious disease frequently affecting children, are lacking in some countries. This study was undertaken to assess the incidence of AOM in children ≤5 years in Saudi Arabia, Oman, Pakistan, and Turkey, as well as the economic burden from a parent/caregiver perspective. Medical records of 4043 children (Saudi Arabia = 1023, Oman = 998, Pakistan = 1022, Turkey = 1000) were retrospectively reviewed and the incidence of AOM episodes calculated from suspected and confirmed cases. Using a standardized Health Economics Questionnaire, parents recorded resource use and expenses incurred per AOM episode [in local currency and converted to US dollars (USD)]. The overall incidence of AOM episodes per 1000 person–years was: Saudi Arabia, 207 [95% confidence interval (CI): 178–238]; Oman, 105 (95% CI: 85–127); Pakistan, 138 (95% CI: 116–163); and Turkey, 99 (95% CI: 79–123). The mean total out-of-pocket healthcare expense incurred by parents/caregivers per episode was: Saudi Arabia USD67.1 [standard deviation (SD) = 93.0], Oman USD16.1 (SD = 16.4), Pakistan USD22.1 (SD = 20.5), and Turkey USD33.6 (SD = 44.9). The incidence of AOM episodes varied across all four countries, probably due to different diagnostic and management practices. Nevertheless, our results confirm that AOM causes a substantial burden to public health, reinforcing the need for cost-effective prevention strategies.

Serotype distribution and penicillin-non-susceptibility of Streptococcus pneumoniae causing invasive diseases in Kuwait: A 10-year study of impact of pneumococcal conjugate vaccines

OBJECTIVES

The impact of PCV7 and PCV13 on pneumococcal infections in Kuwait is not known. Therefore we evaluated the impact on pneumococcal serotype distribution and penicillin-non-susceptibility in invasive infections in Kuwait.

METHODS

Children < 2 y were given PCV7 from Aug 2006 to Jul 2010 (period I), and PCV13 from Aug 2010 to Jul 2013 (period II) with a pre-vaccination period from Aug 2003 to Jul 2006. Serotype and penicillin-non-susceptibility of blood and cerebrospinal fluid isolates from all ages were determined.

RESULTS

In <2 y old children, even with a small number of infections, a drop in PCV7 serotypes was evident after vaccination. For all age groups combined, in the pre-vaccination period, PCV7, PCV13, PCV13 non-PCV7 serotypes and penicillin-non-susceptibility constituted 53.2%, 72.6%, 19.4% and 6.5% of the isolates respectively. PCV7, PCV13 non-PCV7 serotypes and penicillin-non-susceptibility changed to 32.7%, 28.2% and 7.3% (period I) and 6.6%, 22.2% and 8.9% (period II).

CONCLUSIONS

Vaccines reduced invasive infections due to PCV7 serotypes.

Streptococcus pneumoniae from Palestinian nasopharyngeal carriers: serotype distribution and antimicrobial resistance

Infections of Streptococcus pneumoniae in children can be prevented by vaccination; left untreated, they cause high morbidity and fatalities. This study aimed at determining the nasopharyngeal carrier rates, serotype distribution and antimicrobial resistance patterns of S. pneumoniae in healthy Palestinian children under age two prior to the full introduction of the pneumococcal 7-valent conjugate vaccine (PCV7), which was originally introduced into Palestine in a pilot trial in September, 2010. In a cross sectional study, nasopharyngeal specimens were collected from 397 healthy children from different Palestinian districts between the beginning of November 2012 to the end of January 2013. Samples were inoculated into blood agar and suspected colonies were examined by amplifying the pneumococcal-specific autolysin gene using a real-time PCR. Serotypes were identified by a PCR that incorporated different sets of specific primers. Antimicrobial susceptibility was measured by disk diffusion and MIC methods. The resulting carrier rate of Streptococcus pneumoniae was 55.7% (221/397). The main serotypes were PCV7 serotypes 19F (12.2%), 23F (9.0%), 6B (8.6%) and 14 (4%) and PCV13 serotypes 6A (13.6%) and 19A (4.1%). Notably, serotype 6A, not included in the pilot trial (PCV7) vaccine, was the most prevalent. Resistance to more than two drugs was observed for bacteria from 34.1% of the children (72/211) while 22.3% (47/211) carried bacteria were susceptible to all tested antibiotics. All the isolates were sensitive to cefotaxime and vancomycin.

Any or all of these might impinge on the type and efficacy of the pneumococcal conjugate vaccines and antibiotics to be used for prevention and treatment of pneumococcal disease in the country.

Pneumococcal disease in the Arabian Gulf: recognizing the challenge and moving toward a solution

Pneumococcal disease has substantial incidence, morbidity and mortality in older adults. Decreased birth rates and longer lifespans indicate that the global population is aging, although rates of aging differ between countries [1]. In 2010, the proportion of the population aged >60 years in the general Arab Region was 7%, and this proportion is expected to rise to 19% by 2050 for the region as a whole [2]; the United Nations estimates for the individual countries of the Arabian Gulf by 2050 are 25.7%, 24.9%, 20.7%, 26.7% and 10.5% in the Kuwait, Bahrain, Qatar, United Arab Emirates (UAE) and Oman, respectively, which are comparable to the 26.9% predicted for the USA and lower than that predicted in European countries, in which the 2050 estimates are 32.7%, 34.0% and 38.1% for France, the UK and Germany, respectively [1]. Globally and in the Gulf Region, pneumococcal disease is an increasingly important public health burden in the elderly. The burden of pneumococcal disease can be reduced by effective vaccination programs, but the recommendations on pneumococcal vaccination in adults vary widely. The major barriers to vaccine implementation among healthcare professionals are an incomplete awareness of pneumococcal disease and the vaccination options in adults. The Gulf Advocate Group calls for healthcare providers in the countries of the Arabian Gulf (Kuwait, Bahrain, Qatar, United Arab Emirates and Oman) to support awareness and education programs about adult pneumococcal disease, particularly in high-risk groups such as those >65 years of age, those with type 2 diabetes mellitus, hematological malignancy, organ and bone marrow transplantation or chronic kidney or lung diseases and pilgrims undertaking the Hajj to improve pneumococcal disease surveillance and optimize and disseminate recommendations for adult vaccination. The Gulf Advocate Group recommends following the U.S. Centers for Disease Control and Prevention (CDC) guidelines for pneumococcal vaccination [3,4].