PONE-D-21-00134

Acute Kidney Injury in patients with Visceral Leishmaniasis in Northwest Ethiopia

PLOS ONE

Dear Dr. Hailu,

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Academic Editor

PLOS ONE

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3. Thank you for providing the date(s) when patient medical information was initially recorded. Please also include the date(s) on which your research team accessed/retrieved the medical records data used in your study.

4. Thank you for stating the following in the Acknowledgments Section of your manuscript:

"Our acknowledgement also goes to the Drugs for Neglected Disease Initiative (DNDI)

and University of Gondar (UoG) for supporting the Leishmaniasis Research and Treatment

Canter."

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7. We noticed you have some minor occurrence of overlapping text with the following previous publication(s), which needs to be addressed:

- https://www.cell.com/heliyon/fulltext/S2405-8440(18)31817-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2405844018318176%3Fshowall%3Dtrue

- https://apps.who.int/iris/bitstream/handle/10665/311922/IC_Meet_Rep_2019_EN_20619.pdf

- https://cdn.intechopen.com/pdfs-wm/31093.pdf

- http://ispub.com/journal/the_internet_journal_of_tropical_medicine/volume_4_number_1_51/article/spectrum_of_renal_disease_in_visceral_leishmaniasis .html?

In your revision ensure you cite all your sources (including your own works), and quote or rephrase any duplicated text outside the methods section. Further consideration is dependent on these concerns being addressed.

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Reviewers' comments:

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Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: No

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Thank you for this study on AKI in Leishmaniasis; a topic which has limited data. Below are my comments in regard to the manuscript.

1) In the conclusion of the abstract, you report'....proteinuria, hematuria, pyuria and glomerulonephritis. How did you separate glomerulonephritis from hematuria and proteinuria.' Are these not presentations which made you diagnose those patients with glomerulonephritis? You need to review the statement and clarify how glomerulonephritis patients differed from those reported to have proteinuria and hematuria.

2) In the introduction you state'....Visceral Leishmaniasis (VL) is the most serious form of the disease with 100% mortality if left untreated.' May you provide a reference for the statement

3) In the introduction, you wrote '.....In Ethiopia, where SSG and PM combination is used as a first line treatment

and where there is a high rate of HIV'. However, PM abbreviation was not written in full. May you write in full on first use of the abbreviations

4) Under methods section you stated '....Patients included in ongoing clinical trials during this period, charts with significantly incomplete data or patient files that could not be retrieved at LRTC chart room were excluded. (22).' There is need to improve on the gramma in this sentence. It isn't clear in its current form.

5) When defining AKI, it is unclear what creatinine measurement was used to define baseline creatinine. This needs to be specified clearly

6) In the results you write...A total of 17 patients (6.1%) had VL-HIV co-infection, of which alf of the cases (53%; 9/17) were on antiretroviral. There is an error in this statement, it could be that the word 'alf' was to mean half

7) In table 1, specify which drug for VL is 'Other' since it was only used by one person

8) In general, there are a number of grammatical errors, there is need to improve the manuscript by ensuring that the gramma is improved.

9) Risk factors were based on a bivariate table 1. There was need for multivariate analysis to provide better results

10) It is unclear how AKI at admission was defined and how this definition differed from AKI during treatment.

There is also lack of clarity on how dehydration was determined and what was meant by nephrotoxicity; and what nephrotoxic drugs were being referred to or evaluated.

11) Table 3 and Table 4 provide etiology of AKI; from the study design it maybe hard to provide evidence of causality of AKI by these factors

12) In the conclusion section the researcher writes; 'In summary, renal disease occurred before VL diagnosis and during the course of treatment'. However, this may not be entirely based on the results since the study was evaluating patients admitted to hospital and not before diagnosis. The study doesn't evaluate patient before VL diagnosis but provides data on patients who had been managed for VL at the VL treatment centre. There is need to make more clarification on this and the conclusion from the study.

In addition, the researcher states in the conclusion that the renal manisfestations were mild in nature and reversible; however, there was stage 3 AKI and the research never provided recovery data to support the statement of reversibility

Reviewer #2: The authors are to be congratulated on this interesting report of AKI in VL from Ethiopia.

The causes of AKI at admission (present in 10% of patients) included dehydration. HIV and other co-infections were risk factors for AKI (interesting).

AKI also developed in 22 patients who did not have AKI at admission, which could be related to medications.

This manuscript warrants eventual publication, but I recommend some revisions to improve the clarity of the findings reported. As outlined below, the reporting of possible drug-associated AKI is inadequate and possibly even misleading.

Major revision: improved reporting of possible drug-associated AKI

AKI is multi-factorial in this patient cohort.

The authors have done well to separate AKI at admission from AKI during treatment to tease out the effect of medications, for example. Can the authors please confirm (and report in the revised manuscript methods and/or results), whether patients referred to Gondar Hospital had any prior treatment for their VL or other conditions at other centres? Prior treatment with L-AMB or pentavalent antimonials or aminoglycosides/vancomycin/ other nephrotoxic antibiotics. It’s not explicitly stated whether the patients were treatment experienced (potential exposure to nephrotoxins) or treatment naïve. If treatment naïve, this is the “natural history” of AKI in VL as opposed to iatrogenic. As a referral centre, it is possible that patients had been previously hospitalized and treated elsewhere with or without an appropriate diagnosis of VL, for example.

The development of incident AKI after admission in 22 patients may be related to medications (SSG or L-AMB). I strongly recommend that the rate of post-admission AKI be expressed as the proportion of those without AKI at admission who subsequently develop AKI (authors are using the wrong denominator when they divide by the whole cohort n=298):

I believe there should be 268 patients without AKI at admission (298-30):

22/268 = 8.2% (denominator is those without AKI at admission).

I recommend that the rate be compared in those treated with L-AMB and those treated with SSG:

Of the 268 patients without AKI at admission, how many were treated with L-AMB, how many with SSG?

What was the rate of AKI in the SSG group? (excluding patients with AKI at admission)

What was the rate of AKI in the L-AMB group? (excluding patients with AKI at admission)

Could consider a statistical comparison.

If these data can be deduced from the tables 1 and 4, I get the following (excluding patients with AKI at admission):

Drug no AKI post-admission AKI

SSG 204 19

L-AMB 38 3

Total: 242 22 Overall total: 264 (approx. 268, excluding AKI at admission)

Rate of AKI in SSG group: 19/223 = 8.5%

Rate of AKI in L-AMB exposed: 3/41 = 7.3%

OR = 1.16, p-value >0.99

This level of detail is essential to understand the effects of the medications on incident AKI after treatment initiation.

The current reporting is not sufficiently detailed and even misleading:

“Most (67%; 20/30) patients who had AKI at admission were treated with AmBisomeTM whereas 86% (19/22) of patients who develop AKI during VL treatment course were on SSG +PM”

After initial read, I though the SSG was associated with AKI, but a more careful review of the data suggests to me there is no evidence of higher rates of incident AKI in the SSG-treated patients.

This is partially addressed in Table 4. However, with respect to drug treatment, it would be helpful to add to table 4 those patients who did not have AKI at admission or during treatment (n=246, control group without AKI at admission, who did not develop AKI subsequently)– which drugs received and whether the drugs were switched. This could be included as a third column in Table 4 (I realize there wouldn’t be entries for “etiology of AKI” in this group!). This is an essential comparator group to make sense of the treatment numbers.

In summary, the reporting of AKI after admission according to treatment is not sufficiently detailed (Major revision necessary since this is a central mechanism of the AKI in this study).

Minor revisions:

Abstract:

17.4% (52/298) VL patients had AKI: recommend giving the 95% confidence interval on this proportion, since it’s the primary objective of the study.

AmBisome: liposomal amphotericin B. Please use generic rather than trade name

Introduction:

Glucantime: meglumine antimoniate. please use generic rather than trade name. (Introduction, 3rd paragraph)

PM: paromomycin? Please spell out the name with abbreviation when first mentioned (Introduction, 3rd paragraph)

Methods:

“all patients admitted during the study period at LRTC with confirmed diagnosis of VL” – should state the way the diagnosis was confirmed (e.g., confirmed by the presence of amastigotes on splenic or bone marrow aspirate - Giemsa-stain, light microscopy…) Please explicitly state if serology, PCR, and culture were not used for diagnosis.

Sample size calculation:

First, the authors are to be congratulated on including a sample size calculation for this observational study (frequently omitted).

I note that the authors used the alpha=90% level of significance for this calculation (z-score[0.05]=1.64):

n=(p)*(1-p)*(1.64/d)^2 = (0.5)*(1-0.5)*(1.64/0.05)^2 = 270

whereas alpha=95%CI is more standard (z-score[0.025]=1.96):

n=(p)*(1-p)*(1.96/d)^2 = (0.5)*(1-0.5)*(1.96/0.05)^2 = 378

In the end, the estimate of the proportion (50%) is quite different from the observed proportion (17%) and the confidence interval on the proportion is still within +/-5%

Overall, I think the sample size is adequate, but the assumptions of the sample size calculation are different from convention and from the observed proportion. A brief comment in the discussion on the adequacy of the sample size and differences between a priori assumed rate and observed rate may be considered.

The sampling strategy for the chart review is also clear and I congratulate the authors for describing this.

Results.

All but two of the charts reviewed were of male patients?

This is surprising. Although there is a male predominance in VL, it is far from an exclusively male disease. (e.g., male/female ratio was 1.40 in PLOS NTD, Male predominance in reported Visceral Leishmaniasis cases: Nature or nurture? A comparison of population-based with health facility-reported data.)

The ratio in this study would be 296:2 !

I think this requires an explanation why female patients were not included (not likely chance alone).

Risk factors for AKI (Co-infection and HIV): please give odds ratio and 95%CI for the association between HIV and AKI, likewise for co-infections and AKI.

Editorial/language revisions:

clinician judgment of the treating physician: clinical judgment of the treating physician (Methods, Variables and operational definitions, paragraph 2)

Patient’s data confidentially were respected: patient data confidentiality was respected (Methods, ethical considerations)

“The main etiology of AKI at admission and during treatment course were dehydration and nephrotoxicity” – "nephrotoxicity" is not really an etiology (too general a term) – perhaps reword: medication-induced tubular injury or glomerular injury, for example. (Results)

Table 2: AST elevation. LN (missing U for ULN)

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Reviewer #1: No

Reviewer #2: Yes: Michael Hawkes

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Acute Kidney Injury in patients with Visceral Leishmaniasis in Northwest Ethiopia

PONE-D-21-00134R1

Dear Dr. Hailu,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Andrea L. Conroy, PhD

Academic Editor

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Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #2: Thank you for thoroughly addressing my comments. All revisions have been done to my satisfaction. The manuscript is very interesting!

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Michael Hawkes