Trends of Multidrug-Resistant Gram-Negative Bacteria in Tamale Metropolis, Ghana (2020–2023)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 Dear Editor,

Thank you for the opportunity to review the manuscript “Trends of Multidrug-Resistant Gram-Negative Bacteria in Tamale Metropolis, Ghana (2020-2023).” This study addresses a critical and timely issue: the escalating threat of antimicrobial resistance (AMR) in a resource-limited setting. The authors present valuable surveillance data from the Tamale Metropolis, highlighting alarmingly high resistance rates to commonly used antibiotics and an increasing trend in carbapenem resistance. The focus on demographic and temporal trends adds to the study's significance. However, the manuscript in its current form requires substantial revision to address several methodological and result presentation issues before it can be considered for publication. Below are my comments:

Methodology:

Please include a subsection for MDR and state how to determine it.

Als, please include MAR index report from the laboratory data.

Result:

Lines 175 – 181: It will be great if the authors go a step further to identify the most common resistance pattern for the duration of the study (2020 – 2023) across some of the independent  variables. Also, the authors should present the multiple-antimicrobial resistance (MAR) index. This index will give a better indication of what is happening in the environment.

Note: Please include table for the resistance pattern across all the independent variables.

Line 185 - 186: “The estimated period prevalence of multidrug resistance (MDR) among gram-negative bacterial isolates from 2020 to 2023 was 40.6%”. But in the abstract the authors reported 40.8%. Please reconcile.

Lines 195 – 198: Please report the actual events (numbers) instead of reporting percentages for trends. Also, try to explore if you can report a longitudinal trends across the months for the 3 years period to better understand how seasons affect the MDR trends.

Lines 199 – 203: Please move this paragraph to discussion not result section.

Lines 207 – 219: Please re-write this section to include the events (numbers). The section was talking about trends without actual numbers.

Lines 223 – 232: Please re-write the section by including not just the percentages but rather fraction then percentage in bracket or just the numbers. And also, use the actual numbers to plot the graph not percentage. Percentage is a relative form of expression, the actual fraction will give better and less misleading information than percentage.

Note: 2.11, and 2.11.1 sections should be re-written and figures re-plotted using actual number of events not percentages.

Discussion:

Please re-write this section to capture all earlier corrections in the result section and also include discussion on the resistance pattern exhibited by the bacteria and the multiple antimicrobial resistance index.

 

Author Response

Methodology:

Please include a subsection for MDR and state how to determine it.Als, please include MAR index report from the laboratory data

Reply: a subsection for MDR has been included lines 140-146, MAR index was not included because of the timeframe for revision.

Results:

Lines 175 – 181: It will be great if the authors go a step further to identify the most common resistance pattern for the duration of the study (2020 – 2023) across some of the independent variables. Also,the authors should present the multiple-antimicrobial resistance (MAR) index. This index will give a better indication of what is happening in the environment.

Note: Please include table for the resistance pattern across all the independent variables.

Reply: This has been duly corrected

Line 185 - 186: “The estimated period prevalence of multidrug resistance (MDR) among gram-negative bacterial isolates from 2020 to 2023 was 40.6%”. But in the abstract the authors reported 40.8%. Please reconcile.

Reply: This has reconciled

Lines 195 – 198: Please report the actual events (numbers) instead of reporting percentages for trends. Also, try to explore if you can report a longitudinal trend across the months for the 3 years period to better understand how seasons affect the MDR trends.

Reply: Events numbers have been included for lines 195-198

 Lines 199 – 203: Please move this paragraph to discussion not results section.

Reply: Lines 199-203 has been moved to discussion

Lines 207 – 219: Please re-write this section to include the events (numbers). The section was talking about trends without actual numbers.

Comment: Has been re-written to include numbers

Lines 223 – 232: Please re-write the section by including not just the percentages but rather fraction.

then percentage in bracket or just the numbers. And use the actual numbers to plot the graph not percentage. Percentage is a relative form of expression; the actual fraction will give better and less misleading information than percentage. Note: 2.11, and 2.11.1 sections should be re-written, and figures re-plotted using actual number of events not percentages

Reply: Authors have inserted the actual figures to the percentages in the results section, we are however unable to replot the graphs because of time given for revision

Discussion:

Please re-write this section to capture all earlier corrections in the result section and also include discussion on the resistance pattern exhibited by the bacteria and the multiple antimicrobial resistance index.

Reply: Discussion rewritten to capture earlier corrections Multiple antimicrobial resistance Index was not included because of time constraints

Reviewer 2 Report

Comments and Suggestions for Authors

The study describes the presence of MDR in clinical isolates of Gram-negative bacteria in Tamale Metropolis. By incorporating a temporal analysis of MDR and exploring variables such as sex and age, the study provides useful insights into the evolution of MDR in this region. This is highly relevant for identifying the need for interventions to mitigate this globally concerning phenomenon.

While the manuscript is generally well-structured in terms of sections, I suggest distinguishing the Methods and Results sections to improve readability and clarity.

Major comments:

Sections 2.10.2, 2.10.3, and 2.11.1 would benefit from the inclusion of appropriate statistical tests to assess differences between groups. Additionally, indicating statistical significance (e.g., using asterisks above bars in the corresponding figures) would improve the interpretability of the results.

In Section 2.13, it would be valuable to investigate whether there is any association in the co-occurrence of resistance between pairs of antibiotic classes. Identifying such patterns could help determine whether there is co-selection of resistance traits. For example, assessing whether resistance to antibiotic X is more frequently associated with resistance to antibiotic Y than expected by chance.

Throughout the Discussion section, referencing the relevant tables and figures would improve readability and help guide the reader through the findings.

It would be beneficial to discuss whether the most frequently observed resistances are associated with the WHO classification of “Critically Important Antimicrobials for Human Medicine.”

The relatively low MDR observed in Pseudomonas spp. deserves further discussion. Given that  Pseudomonas aeruginosa is part of the ESKAPEE group, it would be important to explore possible explanations for the unexpectedly low resistance levels reported.

Minor comments:

Throughout the manuscript, the date range “2020 - 2023” is sometimes written with an extra dash (“2020 -- 2023”).

Line 134: The words “this table” are used, but no corresponding table is referenced.

Section 2.7: Please specify the alpha level used in the statistical analyses.

Section 2.9.1: Can the authors confirm that there are no duplicate samples from the same patient on the same date (i.e., one isolate per species)? The presence of duplicates could bias the estimation of MDR prevalence.

Line 167: Should the sum of MDR and non-MDR in blood samples not equal 100%? Please verify the reported values (5.3% and 3.6%).

Author Response

Major comments:

Sections 2.10.2, 2.10.3, and 2.11.1 would benefit from the inclusion of appropriate statistical tests to assess differences between groups. Additionally, indicating statistical significance (e.g., using asterisks above bars in the corresponding figures) would improve the interpretability of the results.

Reply: A chi square test was used to assess difference among various groups, this can be found in table 1 and table 2 asterisk have been included to show significant associations

In Section 2.13, it would be valuable to investigate whether there is any association in the co-occurrence of resistance between pairs of antibiotic classes. Identifying such patterns could help determine whether there is co-selection of resistance traits. For example, assessing whether resistance to antibiotic X is more frequently associated with resistance to antibiotic Y than expected by chance.

Reply: Authors are unable to generate this because of revision time constraints

Throughout the Discussion section, referencing the relevant tables and figures would improve readability and help guide the reader through the findings. It would be beneficial to discuss whether the most frequently observed resistances are associated withthe WHO classification of “Critically Important Antimicrobials for Human Medicine.”

Reply: Authors have revised this and included it into the discussion section

The relatively low MDR observed in Pseudomonas spp. deserves further discussion. Given that Pseudomonas aeruginosa is part of the ESKAPEE group, it would be important to explore possible explanations for the unexpectedly low resistance levels reported.

Reply: possible explanation has been incorporated into discussion

Minor comments:

Throughout the manuscript, the date range “2020 - 2023” is sometimes written with an extra dash (“2020 -- 2023”)

Reply: The extra dash has been removed.

Line 134: The words “this table” are used, but no corresponding table is referenced.

Section 2.7: Please specify the alpha level used in the statistical analyses.

Section 2.9.1: Can the authors confirm that there are no duplicate samples from the same patient on the same date (i.e., one isolate per species)? The presence of duplicates could bias the estimation of MDR prevalence

Reply: The authors can confirm there aren’t duplicate samples, each isolate was identified with a unique ID and duplicates and incomplete data were taken care of at the data cleaning stage

Line 167: Should the sum of MDR and non-MDR in blood samples not equal 100%? Please verify the reported values (5.3% and 3.6%).

Reply: The same of MDR and non MDR in on the table in line 167 sum up to 100%

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Editor,
I have gone through the revised manuscript and authors response to reviewers comments. The authors have carefully reviewed the manuscript based on comments raised during first revision. The manuscript has been substantially improved for clarity of methodology and result reporting.

The manuscript can be accepted in its current revised form.

Thank you 

Reviewer 2 Report

Comments and Suggestions for Authors

The revised version of the manuscript addresses the concerns raised in the previous review. I find the changes appropriate and believe the manuscript has been substantially improved.