The Spread of Carbapenemase Genes in Klebsiella pneumoniae in Iran: a Systematic Review

Introduction: The emergence and global spread of carbapenemases produced by Klebsiella pneumoniae is a serious problem to health services worldwide. K. pneumoniae, belonging to the Enterobacteriaceae family, is commonly found in the human gastrointestinal tract and environment, especially in the hospital environment. Carbapenem is administered as the first treatment for severe infections created by multi-drug resistant K. pneumoniae. Despite the fact that the carbapenemase-producing K. pneumoniae has become more prevalent in Iran, few investigations have probed into the prevalence of different carbapenemase genes in Iran. Method: The aim of this study was to examine the prevalence of carbapenemase genes in K. pneumoniae from 2010 to 2018 in Iran. PubMed and Scopus databases were searched for the articles published between 2010 and 2018 in Iran. Results: A total of 25 papers published between 2012 and 2018 were selected. The highest frequency of blaNDM, blaIMP, blaVIM, blaKPC and, blaOXA48 genes were related to cities of Shiraz in 2017 [23 (26.14%)], Hamedan in 2017 [2 (50%)], Babol in 2015 [15 (41.66%)], Isfahan in 2013 [65 (44.83%)] and, and Isfahan in 2018 [90 (76.27%)], respectively. The results showed that the frequency of blaNDM, blaOXA48, and blaIMP genes increased in 2017 and 2018, and there was an increase in the frequency of the blaVIM gene in 2014 and 2015, and the blaKPC gene in 2013. The highest percentage of carbapenemases genes isolated in Iran were related to blaKPC [145 (37.08%)], blaOXA48 [118 (30.18%)], and blaNDM [88 (22.51%)], and the lowest percentages were reported in blaIMP [4 (1.02%)], and blaVIM [36 (9.21%)], respectively. Conclusion: The results of our review showed that blaNDM and blaOXA48 carbapenemase genes have been increasing in Iran, and it seems that traveling is one of the most important factors in the transmission of carbapenemase genes. Keyword: Klebsiella pneumonia, Carbapenemase, NDM, VIM, IMP, KPC, OXA48 *Correspondence to Naghmeh Satarzadeh, Tel: +989363699045, Email: n.satarzadeh@kmu.ac.ir Received December 8, 2020 Accepted February 2, 2021 Published online March 31, 2021 Int J Basic Sci Med. 2021;6(1):1-10 Review Article http://ijbsm.zbmu.ac.ir/ © 2021 The Author(s); Published by Zabol University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Please cite this article as follows: Sadeghi Dousari A, Satarzadeh N. The spread of carbapenemase genes in Klebsiella pneumoniae in Iran: a systematic review. Int J Basic Sci Med. 2021;6(1):110. doi:10.34172/ ijbms.2021.01. Sadeghi Dousari and Satarzadeh International Journal of Basic Science in Medicine. Volume 6, Issue 1, 2021 2 Puerto Rico, Colombia, Greece, Israel, and China.12,13 The blaIMP gene was first reported in Japan in 199114 and then spread around the world. This gene and blaIMP gene are endemic in countries of Egypt, Taiwan, and Japan.15,16 The first report of the blaOXA48 gene was in Turkey in 200317, followed by worldwide expansion in Africa, European countries, and the East and South of the Mediterranean Sea.18-20 blaNDM gene was first reported in Sweden from an Indian patient in 2008 and then spread throughout the world.18 Also, there are a few reports of this gene in Canada and the United States, and the Balkans and the Middle East are believed to be the second reservoir of this gene.21,22 The first time the blaVIM gene was discovered was in 1997 in Verona, Italy, after which it was reported in Greece and then spread around the world.23,24 Considering the fact that several studies have been carried out on carbapenemases produced by K. pneumoniae clinical isolates in different parts of Iran, but information on the mean prevalence of these enzymes is unclear. In this review, we examined the prevalence of carbapenemases produced by K. pneumoniae clinical isolates. Methods Searching the Databases To identify all the related published studies, we searched PubMed and Scopus in English. The medical subject headings (MESH) and keywords used for the search included “Klebsiella pneumoniae” and “carbapenemases” and “Iran”. We also selected the articles published between 2010 and 2018. Study Selection Criteria In this study, only original articles were used. Inclusion criteria included the papers on K. pneumonia isolates from clinical specimens in different regions of Iran. Duplicate papers (n=10) on the two databases and two studies in which the clinical isolates included species other than K. pneumoniae were excluded from the study. Furthermore, in 2010 and 2011, there were no studies on carbapenemases produced by K. pneumonia on Scopus and PubMed databases. Data Extraction The extracted data included the city in which the samples were collected, year, type of sample, type of carbapenemase described, Antibiotic resistance pattern and the references. Results Study Selection The selection process and results are shown in Figure 1. A total of 37 articles were used from the PubMed database (n=21) and Scopus (n=16), of which 12 articles were excluded because ten articles were repeated in both Scopus and PubMed databases, and two articles (Scopus=1 and PubMed=1) evaluated species other than K. pneumoniae. The remaining 25 studies were included in our final analysis, of which 20 were from the PubMed database and five from the Scopus database. Study Characteristics The publication year of the studies was from 2012 to 2018. The majority of the articles were published in 2018 and the smallest number of studies was in 2016. The frequency and percentage of the related articles are shown in Table 1. In 2010 and 2011, no articles related to this study were published on the PubMed and Scopus databases. Most of the studies were in Tehran (n = 9) and Isfahan (n = 7) (Figure 2). Frequency of clinical samples and number and percentage of these specimens are presented in Table 2 and Table 3, respectively. The largest clinical samples are related to unknown [981 (35.10%)], urine [705 (25.22%)], Figure 1. The Process of Selection Articles Uses in This Study.

Puerto Rico, Colombia, Greece, Israel, and China. 12,13 The blaIMP gene was first reported in Japan in 1991 14 and then spread around the world. This gene and blaIMP gene are endemic in countries of Egypt, Taiwan, and Japan. 15,16 The first report of the blaOXA48 gene was in Turkey in 2003 17 , followed by worldwide expansion in Africa, European countries, and the East and South of the Mediterranean Sea. [18][19][20] blaNDM gene was first reported in Sweden from an Indian patient in 2008 and then spread throughout the world. 18 Also, there are a few reports of this gene in Canada and the United States, and the Balkans and the Middle East are believed to be the second reservoir of this gene. 21,22 The first time the blaVIM gene was discovered was in 1997 in Verona, Italy, after which it was reported in Greece and then spread around the world. 23,24 Considering the fact that several studies have been carried out on carbapenemases produced by K. pneumoniae clinical isolates in different parts of Iran, but information on the mean prevalence of these enzymes is unclear. In this review, we examined the prevalence of carbapenemases produced by K. pneumoniae clinical isolates.

Searching the Databases
To identify all the related published studies, we searched PubMed and Scopus in English. The medical subject headings (MESH) and keywords used for the search included "Klebsiella pneumoniae" and "carbapenemases" and "Iran". We also selected the articles published between 2010 and 2018.

Study Selection Criteria
In this study, only original articles were used. Inclusion criteria included the papers on K. pneumonia isolates from clinical specimens in different regions of Iran. Duplicate papers (n=10) on the two databases and two studies in which the clinical isolates included species other than K. pneumoniae were excluded from the study.
Furthermore, in 2010 and 2011, there were no studies on carbapenemases produced by K. pneumonia on Scopus and PubMed databases.

Data Extraction
The extracted data included the city in which the samples were collected, year, type of sample, type of carbapenemase described, Antibiotic resistance pattern and the references.

Study Selection
The selection process and results are shown in Figure  1. A total of 37 articles were used from the PubMed database (n=21) and Scopus (n=16), of which 12 articles were excluded because ten articles were repeated in both Scopus and PubMed databases, and two articles (Scopus=1 and PubMed=1) evaluated species other than K. pneumoniae. The remaining 25 studies were included in our final analysis, of which 20 were from the PubMed database and five from the Scopus database.

Study Characteristics
The publication year of the studies was from 2012 to 2018. The majority of the articles were published in 2018 and the smallest number of studies was in 2016. The frequency and percentage of the related articles are shown in Table  1. In 2010 and 2011, no articles related to this study were published on the PubMed and Scopus databases.
Frequency of clinical samples and number and percentage of these specimens are presented in Table 2 and Table 3 [5 (20%)]. Furthermore, most specimens were collected from intensive care units (ICU) and burns wards.
According  T e h r a n I s f a h a n K a s h a n H a m a d a n K e r m a n S h i r a z B a n d a

60
T e h r a n I s f a h a n K a s h a n H a m a d a n K e r m a n S h i r a z B a n d a     Figure 5.

Discussion
Infections with multi-drug resistant bacteria as carbapenem-resistant K. pneumoniae are considered as a serious problem to global health. 50 The extensive dissemination of K. pneumoniae carbapenemases producer has led to the spread of this resistant pathogen worldwide. 8,51,52 The present study was conducted to estimate the prevalence of carbapenemase genes in K. pneumoniae carbapenemase genes of K. pneumoniae in different cities of Iran. According to our findings, most studies have been conducted in Tehran [9 (36%)] and then in Isfahan [7 (28%)], because Tehran is the capital of Iran and enjoys more facilities, more research centers, more medical schools, and treatment centers. Isfahan is also one of the large and densely populated provinces of Iran and is close to Tehran. There were an almost equal number of studies in other Iranian cities.
The results of this review showed that the most clinical specimens were from urine and respiratory secretions due to the easy colonization of K. pneumoniae in the respiratory tract system and the urinary tract system.
According to the results of this review, the rate of resistance to carbapenem antibiotics in K. pneumoniae varied from 5.6% to 63%, indicating a high range of resistance to these antibiotics and since they are the last line of treatment for severe infections, they should be administered with caution. Also, a recent report indicated that the rate of antibiotic resistance had increased in Portugal. 53 Widespread antibiotic resistance examination    Genes that identified using phenotypic tests.
-: reported gene. in European countries shows that the mean percentage of resistance against third-generation cephalosporins antibiotics (ceftazidime, cefotaxime) is 30.3%. 54 The highest antibiotic resistance in K. pneumoniae in 10 years based on the articles used in this study was related to the cephalosporins antibiotics.
The results showed that the most common carbapenemase genes were related to blaKPC [145 (37.08%)], blaOXA48 [118 (30.18%)], and blaNDM [88 blaNDM is the most common carbapenemase in Europe, India, North America, Pakistan, Australia and other parts of Asia. 30 The blaNDM gene increased slightly in 2014 and 2015 but increased significantly in 2017 and 2018 based on the findings of the present study. blaIMP and blaVIM were reported in South America, North America, Asia, Australia, and Europe. 34 The results of our study also demonstrated that the frequency of the blaIMP gene increased only in 2017 and the blaVIM gene became more prevalent in 2017 but decreased gradually in 2018. blaKPC was reported to be the most common carbapenemase in the United States and blaOXA was reported in Europe, Turkey, northern Africa and the Middle East. 55 In our study, the blaOXA48 gene increased gradually only in 2017 and 2018 and blaKPC gene increased in 2013 and then decreased gradually until 2018. The results of this review during 2010-2018 showed that the blaNDM, blaOXA48 and blaIMP genes increased in 2017 and 2018 more than in eight years ago and the blaVIM gene in 2014 and 2015 and the blaKPC gene in 2013 increased and then declined, respectively. This increase is due to the easy dissemination of these genes by plasmids among Enterobacteriaceae bacteria, and on the other hand, the importance of studying resistance to carbapenems as a treatment for severe infections.
Nahid et al 56 collected 356 clinical isolates of the hospitals. Out of a total of 356 isolates, 160 displayed imipenem resistance and 131 showed MBLs production. In MBL positive isolates, 31 isolates reported harboring the blaNDM-1 gene out of which 13 (41.93%) were K. pneumoniae. In 2016, Khan et al reported that the prevalence of the blaNDM gene was 78%, 57 which indicates the high prevalence of this gene in Pakistan. This high prevalence is because the primary source of the blaNDM genes was in India and Pakistan. [58][59][60] Also, the high prevalence of this gene in the study in Kerman, Iran, as one of the cities close to the border with Pakistan, can be due to people coming from the bordering countries for trade or treatment. In Turkey, the prevalence of the blaNDM gene was reported to be 19% in 2013 and 52.9% in 2016, respectively. 61,62 According to the studies in Turkey, the high prevalence of the blaNDM gene in Tabriz may be because of the trade and treatment of people coming from the bordering countries in this city.

Limitations of the Study
In this study, Persian databases such as Scientific Information Database (SID) and Magiran were not used and only articles in English were examined.

Conclusion
Whereas information from all cities of Iran is still limited, this systematic review provides a picture of the prevalence of carbapenemase genes in K. pneumoniae in Iran. The findings showed that resistant genes of carbapenemases like the blaNDM and blaOXA48 genes are becoming more prevalent in Iran, and worldwide, which is worrying and alarming. Traveling is probably one of the main reasons for the transmission of carbapenemase genes. Also, physicians should be careful about the correct use of antibiotics.

Authors' Contribution
ASD designed the study, performed the searching of databases, and wrote the manuscript. NS performed the searching of databases and revised the manuscript.

Ethical Approval
Not applicable.