Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

These authors describe what they call atypical presentations of Mpox infection. The descriptions are based on which organ is involved. The authors also point out differences in pathogenesis between clades I and II. The approach of the authors in their review offers insight into Mpox pathogenesis. However, for a review of this length, there is a deficiency of figures (only one). A few suggestions for improvement are listed below.

1.Figure 1. Most important comment. Figure 1 is the only figure in the manuscript. This figure is very important. The authors point out numerous percentile differences in the text in organ involvement by clades I and II. Yet the percentiles under each picture of an organ in figure 1 do not differentiate between clades I and II. This presentation is very confusing. Strongly suggest that the authors redo figure 1 and draw a Figure 1A (clade I) and a Figure 1B (clade II). Place the correct percentiles under each organ for each clade beside picture of a human.

2.Clinical presentation. Lines 109-110. The authors have overlooked an interesting type of rash that is more common in children and adolescents in central and western Africa. There are several reports that children with Mpox often are coinfected with varicella, or vice-versa, children with varicella can be coinfected with Mpox in central and western Africa. In some studies, the percentage was high. The authors should add this interesting bit of information into their text and also insert two new references.(i )Khallafallah et al, Reassessment of evidence about coinfection of chickenpox and monkeypox (mpox) in African children, VIRUSES 2022; (ii) Stephen et al, The epidemiological trend of monkeypox and monkeypox-varicella zoster viruses co-infection in North-Eastern Nigeria. Front Public Health. (2022).

3.Psychiatric complications. Line 344. Combine the section called post-viral syndrome (line 503) into the Psychiatry section. Both sections are short and they complement one another.

4.New section of review. In place of the deleted section called post-viral syndrome, add a new section called Coinfections with Mpox. The authors imply that coinfections may enhance the virulence of a Mpox infection in several locations of manuscript. That hypothesis is reasonable. The authors mention several coinfections, including syphilis, HIV, HSV type 1, Hepatitis B and Hepatitis C in the different sections earlier in the review. In this new section, consolidate the comments made in previous sections into a new section. Also suggest that the authors draw a figure here to illustrate again which organs in a human have been reported to be coinfected by Mpox and a second pathogen. For example, under liver, add hepatitis B and C.

5.Coinfection with HSV type 2 was not included in manuscript. Reference about Mpox and HSV type 2 was overlooked. Please discuss this case in section on coinfections and add reference to this manuscript: Monkeypox and Herpes Simplex Virus Type 2 Coinfection: Case Report of Perianal Lesions in HIV-Positive Patient, Sexually Transmitted Diseases 49:769, 2022.

6.Conclusions. lines 534-539. Move these comments about coinfections from the Conclusions section into the new section on Coinfections (See Comment 4). Instead, suggest that the authors finalize their Conclusion with a link to WHO and their statement about Mpox: The WHO continues to emphasize core response strategies—the 5Cs (Coordination, Surveillance, Community protection, Care, and Countermeasures).

Author Response

Response to Reviewer 1

We thank the reviewer for this suggestion and have modified the figure. Unfortunately, due to the paucity of literature on certain complications it is not possible to provide percentages for each clade. We have clarified in the figure where clade data has been reported.

2.Clinical presentation. Lines 109-110. The authors have overlooked an interesting type of rash that is more common in children and adolescents in central and western Africa. There are several reports that children with Mpox often are coinfected with varicella, or vice-versa, children with varicella can be coinfected with Mpox in central and western Africa. In some studies, the percentage was high. The authors should add this interesting bit of information into their text and also insert two new references.(i )Khallafallah et al, Reassessment of evidence about coinfection of chickenpox and monkeypox (mpox) in African children, VIRUSES 2022; (ii) Stephen et al, The epidemiological trend of monkeypox and monkeypox-varicella zoster viruses co-infection in North-Eastern Nigeria. Front Public Health. (2022).

We thank the reviewer for this suggestion and have included this information and references in the clinical presentation section of the manuscript.

3.Psychiatric complications. Line 344. Combine the section called post-viral syndrome (line 503) into the Psychiatry section. Both sections are short and they complement one another.

We appreciate this reviewer suggestion and have combined these sections.

We have added a co-infection section to the manuscript.

5.Coinfection with HSV type 2 was not included in manuscript. Reference about Mpox and HSV type 2 was overlooked. Please discuss this case in section on coinfections and add reference to this manuscript: Monkeypox and Herpes Simplex Virus Type 2 Coinfection: Case Report of Perianal Lesions in HIV-Positive Patient, Sexually Transmitted Diseases 49:769, 2022.

We have included this this as part of the co-infections section of the manuscript.

We thank the reviewer for the suggestion and have made these changes to the conclusion of the manuscript.

Reviewer 2 Report

Comments and Suggestions for Authors

This is a timely review of the less common, multi-organ manifestations of mpox and of the mechanisms that may underlie them. The structure of the manuscript is logical and the authors draw on clinical series, systematic reviews and meta-analyses, non-human primate studies and organoid work.

However, several issues should be addressed.

Major comments

1. The review lists skin, gastrointestinal tract, liver, kidney, lung, brain and reproductive organs as targets of dissemination, but it contains no section on urogenital or pulmonary involvement, and reproductive-tract disease is not addressed. One further area that should be addressed is absent: mpox in pregnancy.

2. No details on the method of literature selection. No search strategy, date range, database or inclusion criteria are given.

3. Figure 1 combines percentages with incompatible denominators. Displaying these side by side as if they were comparable prevalences is misleading. The figure should give, for each value, the source reference and the denominator/population and/or the legend should state that estimates derive from heterogeneous study designs.

4. Case-fatality figures require context, quoting 3.6% for clade II against 10.6% for clade I, in a sentence about the 2022 clade IIb outbreak, is liable to mislead. These are pooled estimates dominated by historical endemic-setting studies, whereas case fatality observed during the 2022 clade IIb outbreak in non-endemic countries was roughly two orders of magnitude lower. Please state the populations and time periods the figures refer to, and separate historical clade-level estimates from 2022 outbreak experience.

5. Reference [14] (Chittenden T. BH3 Domains: Intracellular Death-Ligands Critical for Initiating Apoptosis. Cancer Cell 2002) seems unrelated to the statement it supports.

6. Dissemination and viraemia are asserted rather than evidenced. The hypothesis that the virus infects lymphocytes and monocytes/macrophages and disseminates haematogenously is central to the whole review, it underpins the ophthalmic, cardiovascular, gastrointestinal and hepatic sections, yet it is supported almost entirely by animal data and by a single narrative review. Human virological data on viral DNA in blood and on viral DNA distribution across anatomical compartments, are directly relevant and would substantially strengthen this argument. The authors may wish to consider:

Rizzo A, Moschese D, Trentacapilli B, et al. Viral bloodstream detection in mpox patients: an observational multicentric study. J Infect 2023;87(1):54-56. doi:10.1016/j.jinf.2023.04.001
Meschi S, Colavita F, Carletti F, Mazzotta V, Matusali G, Specchiarello E, Ascoli Bartoli T, Mondi A, Minosse C, Giancola ML, Pinnetti C, Valli MB, Lapa D, Mizzoni K, Sullivan DJ, Ou J, Focosi D, Girardi E, Nicastri E, Antinori A, Maggi F. MPXV DNA kinetics in bloodstream and other body fluids samples. Sci Rep. 2024 Jun 12;14(1):13487. doi: 10.1038/s41598-024-63044-5
Rizzo A, Mileto D, Moschese D, et al. Role of multi-site sampling in the diagnosis of human Monkeypox. J Infect2023;86(2):154–225. doi:10.1016/j.jinf.2022.12.010

The first and the second report directly about bloodstream detection of viral DNA in patients and therefore to the plausibility of haematogenous spread in humans; the third also bears on the distribution of detectable virus across sampling sites, which is relevant both to the dissemination argument and to the discussion of tissue-specific manifestations.

7. STI co-infection is raised as a knowledge gap but not developed. The authors twice note that the contribution of non-HIV sexually transmitted infections to mpox complications is unknown, citing only the 29% figure. Cohort data or other reviews on concurrent STI diagnoses in people with mpox exist and should be discussed, for example:

Nakhaie M, Rukerd MRZ, Farsiu N, Bashash D, Mahani FK, Arefinia N, Charostad J, Zarei M, Behnezhad F. Mpox and Viral Co-Infections: A Narrative Review. Health Sci Rep. 2025 Feb 25;8(2):e70464. doi: 10.1002/hsr2.70464. PMID: 40012816; PMCID: PMC11861034.
Rizzo A, Pozza G, Salari F, et al. Concomitant diagnosis of sexually transmitted infections and human monkeypox in patients attending a sexual health clinic in Milan, Italy. J Med Virol 2023;95(1):e28328. doi:10.1002/jmv.28328

This is particularly relevant to the proctitis discussion, where co-infection might be a confounder of the claim that proctitis reflects direct rectal inoculation, and to the neurological section, where syphilis co-infection in four of the reported neuroinflammatory cases is noted but not pursued.

9. Several references appear to be duplicate entries under different numbers, examples: [32] and [35]; [75] and [79]; [76] and [78]; [86] and [92]. Reference [78] is also incomplete (no journal, volume or DOI). The list and in-text citations should be carefully checked.

Minor comments

Nomenclature, the title uses "Mpox virus", while the revised abstract and the keywords use "Monkeypox virus (MPXV)". The abbreviation list should also be checked after this is resolved. Adopt one convention consistently and apply it to the manuscript.
Line 229-231, the statement that viral encephalitis has been reported for MPXV and VARV "but not for vaccinia virus" needs qualification, given the documented post-vaccinial encephalitis and encephalomyelitis literature. Distinguishing direct viral CNS infection from immune-mediated post-vaccinial disease would make the point defensible and would also connect with the observation at lines 244-247 that MPXV DNA was absent from CSF in both reported cases.
Conclusions, the research priorities are appropriate but generically stated. Linking each one back to the specific experimental gap identified earlier (for example, absence of clade I organoid data for cardiac tissue, absence of human viraemia data stratified by complication, absence of standardised psychiatric instruments) would make the section considerably more useful.
Keywords, consider adding terms reflecting the actual content.

Comments on the Quality of English Language

English language editing is recommended.

Examples (leaving aside tracked-change artifacts):

line 88, "These virions are transported toward the plasma membrane and fuses with the host-cell membrane"
line 121, "While the complication associated with mpox infection are relatively infrequent"
line 305, "failed to produce detectale gasdermin B cleavage"
lines 439–440, "abdominal pain appearing to be a more common in African studies compared to than non-African ones".

Author Response

Reviewer 2

However, several issues should be addressed.

Major comments

The review lists skin, gastrointestinal tract, liver, kidney, lung, brain and reproductive organs as targets of dissemination, but it contains no section on urogenital or pulmonary involvement, and reproductive-tract disease is not addressed. One further area that should be addressed is absent: mpox in pregnancy.

We have added respiratory and urogenital involvement to the clinical presentation section, but have not included these a stand-alone sections as they are relatively common following infection and we have endeavoured to create a review of the less-common, more atypical presentations of MPXV infection. We agree that mpox in pregnancy is uncommon, it is an extensive topic that would require a separate manuscript to fully investigate all aspects properly. This could certainly be considered as a topic for a future review.

No details on the method of literature selection. No search strategy, date range, database or inclusion criteria are given.

We regret this oversight and have included this information.

Figure 1 combines percentages with incompatible denominators. Displaying these side by side as if they were comparable prevalences is misleading. The figure should give, for each value, the source reference and the denominator/population and/or the legend should state that estimates derive from heterogeneous study designs.

Case-fatality figures require context, quoting 3.6% for clade II against 10.6% for clade I, in a sentence about the 2022 clade IIb outbreak, is liable to mislead. These are pooled estimates dominated by historical endemic-setting studies, whereas case fatality observed during the 2022 clade IIb outbreak in non-endemic countries was roughly two orders of magnitude lower. Please state the populations and time periods the figures refer to, and separate historical clade-level estimates from 2022 outbreak experience.

We have changed this section to more accurately reflect updated case-fatality rates and have include the caveats that should be considered when interpreting these values.

Reference [14] (Chittenden T. BH3 Domains: Intracellular Death-Ligands Critical for Initiating Apoptosis. Cancer Cell 2002) seems unrelated to the statement it supports.

We have corrected this error and added the appropriate reference.

Dissemination and viraemia are asserted rather than evidenced. The hypothesis that the virus infects lymphocytes and monocytes/macrophages and disseminates haematogenously is central to the whole review, it underpins the ophthalmic, cardiovascular, gastrointestinal and hepatic sections, yet it is supported almost entirely by animal data and by a single narrative review. Human virological data on viral DNA in blood and on viral DNA distribution across anatomical compartments, are directly relevant and would substantially strengthen this argument. The authors may wish to consider:

Rizzo A, Moschese D, Trentacapilli B, et al. Viral bloodstream detection in mpox patients: an observational multicentric study. J Infect 2023;87(1):54-56. doi:10.1016/j.jinf.2023.04.001
Meschi S, Colavita F, Carletti F, Mazzotta V, Matusali G, Specchiarello E, Ascoli Bartoli T, Mondi A, Minosse C, Giancola ML, Pinnetti C, Valli MB, Lapa D, Mizzoni K, Sullivan DJ, Ou J, Focosi D, Girardi E, Nicastri E, Antinori A, Maggi F. MPXV DNA kinetics in bloodstream and other body fluids samples. Sci Rep. 2024 Jun 12;14(1):13487. doi: 10.1038/s41598-024-63044-5
Rizzo A, Mileto D, Moschese D, et al. Role of multi-site sampling in the diagnosis of human Monkeypox. J Infect2023;86(2):154–225. doi:10.1016/j.jinf.2022.12.010

We appreciate the reviewer suggestion and have included the references.

Reviewer 3 Report

Comments and Suggestions for Authors

Comments and suggestions are present in the attached file.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Could be improved.

Author Response

Reviewer 3

This review by Kankanamge et al. addresses a highly relevant topic and summarizes current

knowledge on atypical and disseminated manifestations of mpox infection. The manuscript

is generally well organized and covers a broad range of organ systems; however, in its

current form it remains largely descriptive and would benefit from a stronger mechanistic

focus and more critical evaluation of the available evidence. Therefore, I recommend major

revision.

- The title emphasizes the pathogenesis of atypical mpox manifestations, however, much of

the review is descriptive and focuses on clinical presentation. The mechanistic discussion is

uneven across sections and should be expanded or alternatively the title should be modified

to better reflect the content.

We thank the reviewer for this suggestion and have modified the title.

-Throughout the manuscript, several conclusions regarding clade-specific effects, viral

dissemination, and routes of transmission are presented with limited supporting evidence.

The authors should more clearly differentiate established findings from hypotheses and

speculative interpretations.

We have added language throughout the manuscript to better clarify what are the speculative interpretations.

- The manuscript frequently refers to differences between MPXV clades, yet the biological

basis for these differences is only superficially discussed. Given the increasing interest in clade

Ib and its expanding geographic distribution, a more focused discussion of clade-specific

pathogenic mechanisms would substantially strengthen the review.

We thank the reviewer for the suggestion and have included clade-specific pathogenesis where we can. Unfortunately, there is a limited amount of mechanistic studies directly comparing viral clades.

- HIV infection and immunosuppression are repeatedly mentioned as factors associated with

more severe disease and complications. A dedicated section discussing the role of host

immunity in dissemination and organ involvement would improve the manuscript.

We appreciate the perspective of the reviewer and have included where relevant the role of HIV in MPXV pathogenesis. While we agree that investigation of the host immune response, and the role played by HIV in the MPXV disease process would be interesting, it would require its own separate review to properly describe all aspects. This could certainly be considered as a topic for future reviews.

- A summary table linking affected organ systems, reported complications, proposed

pathogenic mechanisms, and available evidence would significantly improve readability and

overall value of the review. Another recommendation would be adding more graphical

schematics to support main messages.

We have modified our current figure to improve clarity. We believe adding a table will be challenging to incorporate all the reference.

Minor comments:

- The hepatitis section is relatively brief and contains limited mechanistic discussion

compared with the other sections.

We agree and have noted that this is likely due to a combination of how infrequently hepatitis occurs following infection, the difficulty in obtaining biopsies, and the few case reports that exist. We have included the scant pathological data that is available but are unable to comment further. We there is a need for further mechanistic studies.

- The manuscript would benefit from careful English language editing.

We have reviewed the manuscript to improve readability.

- Double-check references – [14] is unrelated and some others are duplicated - 32/35,

46/91, 69/93, 75/79

We have corrected the errors.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have made the recommended modifications to their manuscript. The overall quality of the manuscript has been improved.

Author Response

We once again thank the reviewer.

Reviewer 2 Report

Comments and Suggestions for Authors

Most comments have been properly addressed, However:

1) English edit is still required.
Remaining errors include “historial”, “5-21days”.

2) Same papers still appear under different numbers, including:

• Zong et al., Vaccines 2025, [36] and [48]

• Li et al., Emerg Microbes Infect 2024, [49], [76], and [99]

• Ramakrishnan et al., BMJ Open Gastroenterol 2024, [82] and [86]

• Ritter et al., J Infect Dis 2024, [93] and [98]

• Closely related Simadibrata GI reviews, [83] and [85]

This must be cleaned and in-text citations renumbered.

Author Response

We thank the reviewer for identifying these errors. We have corrected them in re-submitted version of the manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors has significantly improved the manuscript and fixed the issues. The manuscript is now ready to be published.

Author Response

We once again thank the reviewer.

Review Reports