Documents from the SIAIP Commissions

Issue 3 - 2026

Skin barrier and cutaneous microbiota in the primary prevention of atopic dermatitis: current evidence and future perspectives

Authors

Salvatore Cascone , Angela Klain , Carolina Grella , Valentina Cattivera , Cecilia Fabiano , Francesca Galletta , Sara Manti , Antonio Andrea Senatore , Amelia Licari , Michele Miraglia del Giudice , Gian Luigi Marseglia , Cristiana Indolfi , on behalf of SIAIP Primary and Secondary Prevention of Allergic Diseases Commission

Keywords: atopic dermatitis, skin barrier, cutaneous microbiota, primary prevention, infant
DOI: 10.53151/2531-3916/2026-2768
Publication Date: 2026-09-30

Summary

Background. Atopic dermatitis (AD) is often the earliest manifestation of allergic multimorbidity in childhood. Epidermal barrier impairment and altered microbial colonization can be detected before overt disease, supporting a unified barrier-microbiota model of pathogenesis.

Aim. To examine the biological basis and clinical evidence for primary prevention of pediatric AD through interventions directed at skin barrier function, microbial ecology, or both.

Methods. Evidence from longitudinal cohorts, randomized trials, systematic reviews, meta-analyses, and international guidance was appraised narratively, with emphasis on pediatric populations and clinically diagnosed AD.

Main findings. Current evidence highlights a complex and evolving preventive landscape. While large pragmatic trials have not demonstrated a consistent benefit of routine neonatal emollient use, emerging data suggest that timing, formulation, and biological risk stratification may influence preventive efficacy. Microbiota-directed strategies, especially selected probiotic interventions, have shown promising but strain- and timing-dependent effects, supporting further investigation of integrated barrier- and microbiota-based approaches.

Conclusions. Infant skincare should not be presented as proven AD prevention. Future trials should enroll biologically defined risk groups, target prespecified windows, integrate barrier and microbial biomarkers, and use harmonized outcomes.

References

  1. Odhiambo JA, Williams HC, Clayton TO, et al.; ISAAC Phase Three Study Group. Global variations in prevalence of eczema symptoms in children from ISAAC Phase Three. J Allergy Clin Immunol 2009;124:1251-1258.e23. https://doi.org/10.1016/j.jaci.2009.10.009.
  2. Paller AS, Spergel JM, Mina-Osorio P, Irvine AD. The atopic march and atopic multimorbidity: Many trajectories, many pathways. J Allergy Clin Immunol 2019;143:46-55. https://doi.org/10.1016/j.jaci.2018.11.006.
  3. Illi S, von Mutius E, Lau S, Nickel R, Grüber C, Niggemann B, Wahn U; Multicenter Allergy Study Group. The natural course of atopic dermatitis from birth to age 7 years and the association with asthma. J Allergy Clin Immunol 2004;113:925-931. https://doi.org/10.1016/j.jaci.2004.01.778.
  4. Klain A, Indolfi C, Dinardo G, et al. Marcia atopica: ci sono nuove evidenze? Rivista di Immunologia e Allergologia Pediatrica 2021;35:17-22. https://doi.org/10.53151/2531-3916-2021-5.
  5. Maiello N, Giannetti A, Ricci G, et al. Atopic dermatitis and atopic march: which link? Acta Biomed 2021;92(S7):e2021525. https://doi.org/10.23750/abm.v92iS7.12430.
  6. Stefanovic N, Irvine AD. Filaggrin and beyond: New insights into the skin barrier in atopic dermatitis and allergic diseases, from genetics to therapeutic perspectives. Ann Allergy Asthma Immunol 2024;132:187-195. https://doi.org/10.1016/j.anai.2023.09.009.
  7. Kennedy EA, Connolly J, Hourihane JO, et al. Skin microbiome before development of atopic dermatitis: Early colonization with commensal staphylococci at 2 months is associated with a lower risk of atopic dermatitis at 1 year. J Allergy Clin Immunol 2017;139:166-172. https://doi.org/10.1016/j.jaci.2016.07.029.
  8. Williams MR, Gallo RL. Evidence that Human Skin Microbiome Dysbiosis Promotes Atopic Dermatitis. J Invest Dermatol 2017;137:2460-2461. https://doi.org/10.1016/j.jid.2017.09.010.
  9. Demessant-Flavigny AL, Connétable S, Kerob D, et al. Skin microbiome dysbiosis and the role of Staphylococcus aureus in atopic dermatitis in adults and children: A narrative review. J Eur Acad Dermatol Venereol 2023;37(Suppl 5):3-17. https://doi.org/10.1111/jdv.19125.
  10. Horimukai K, Morita K, Narita M, et al. Transepidermal water loss measurement during infancy can predict the subsequent development of atopic dermatitis regardless of filaggrin mutations. Allergol Int 2016;65:103-108. https://doi.org/10.1016/j.alit.2015.09.004.
  11. Le LN, Luu QQ, Pham DL. Newborn transepidermal water loss and gestational age as predictive factors for infant atopic dermatitis in the first three months of age. Allergy Asthma Immunol Res 2026;18:123-131. https://doi.org/10.4168/aair.2026.18.1.123
  12. Palmer CN, Irvine AD, Terron-Kwiatkowski A, et al. Common loss-of-function variants of the epidermal barrier protein filaggrin are a major predisposing factor for atopic dermatitis. Nat Genet 2006;38:441-446. https://doi.org/10.1038/ng1767.
  13. Irvine AD, McLean WH, Leung DY. Filaggrin mutations associated with skin and allergic diseases. N Engl J Med 2011;365:1315-27. https://doi.org/10.1056/NEJMra1011040.
  14. Bønnelykke K, Pipper CB, Tavendale R, et al. Filaggrin gene variants and atopic diseases in early childhood assessed longitudinally from birth. Pediatr Allergy Immunol 2010;21:954-61. https://doi.org/10.1111/j.1399-3038.2010.01073.x.
  15. van den Bogaard EH, Elias PM, Goleva E, et al. Targeting Skin Barrier Function in Atopic Dermatitis. J Allergy Clin Immunol Pract 2023;11:1335-1346. https://doi.org/10.1016/j.jaip.2023.02.005. .
  16. Chu V, Ong PY. Constant vigilance! Managing threats to the skin barrier. Ann Allergy Asthma Immunol 2024;132:678-685. https://doi.org/10.1016/j.anai.2024.02.004.
  17. Hannigan GD, Grice EA. Microbial ecology of the skin in the era of metagenomics and molecular microbiology. Cold Spring Harb Perspect Med 2013;3:a015362. https://doi.org/10.1101/cshperspect.a015362.
  18. Barnes CJ, Clausen ML, Asplund M, et al. Temporal and Spatial Variation of the Skin-Associated Bacteria from Healthy Participants and Atopic Dermatitis Patients. mSphere 2022;7:e0091721. https://doi.org/10.1128/msphere.00917-21. Erratum in: mSphere 2023;8:e0031923. https://doi.org/10.1128/msphere.00319-23.
  19. Meylan P, Lang C, Mermoud S, et al. Skin Colonization by Staphylococcus aureus Precedes the Clinical Diagnosis of Atopic Dermatitis in Infancy. J Invest Dermatol 2017;137:2497-2504. https://doi.org/10.1016/j.jid.2017.07.834.
  20. Ito T, Nakamura Y. The skin barrier and microbiome in infantile atopic dermatitis development: can skincare prevent onset? Int Immunol 2024;36:579-584. https://doi.org/10.1093/intimm/dxae038.
  21. Petersen EBM, Skov L, Thyssen JP, et al. Role of the Gut Microbiota in Atopic Dermatitis: A Systematic Review. Acta Derm Venereol 2019;99:5-11. https://doi.org/10.2340/00015555-3008.
  22. Horimukai K, Morita K, Narita M, et al. Application of moisturizer to neonates prevents development of atopic dermatitis. J Allergy Clin Immunol 2014;134:824-830.e6. https://doi.org/10.1016/j.jaci.2014.07.060.
  23. Simpson EL, Chalmers JR, Hanifin JM, et al. Emollient enhancement of the skin barrier from birth offers effective atopic dermatitis prevention. J Allergy Clin Immunol 2014;134:818-823. https://doi.org/10.1016/j.jaci.2014.08.005.
  24. Chalmers JR, Haines RH, Bradshaw LE, et al.; BEEP study team. Daily emollient during infancy for prevention of eczema: the BEEP randomised controlled trial. Lancet 2020;395:962-972. https://doi.org/10.1016/S0140-6736(19)32984-8.
  25. Bradshaw LE, Wyatt LA, Brown SJ, et al. Emollients for prevention of atopic dermatitis: 5-year findings from the BEEP randomized trial. Allergy 2023;78:995-1006. https://doi.org/10.1111/all.15555.
  26. Skjerven HO, Rehbinder EM, Vettukattil R, et al. Skin emollient and early complementary feeding to prevent infant atopic dermatitis (PreventADALL): a factorial, multicentre, cluster-randomised trial. Lancet 2020;395:951-961. https://doi.org/10.1016/S0140-6736(19)32983-6. Erratum in: Lancet 2020;395:e53. https://doi.org/10.1016/S0140-6736(20)30422-0.
  27. Ní Chaoimh C, Lad D, Nico C, et al. Early initiation of short-term emollient use for the prevention of atopic dermatitis in high-risk infants-The STOP-AD randomised controlled trial. Allergy 2023;78:984-994. https://doi.org/10.1111/all.15491.
  28. Kelleher MM, Phillips R, Brown SJ, et al. Skin care interventions in infants for preventing eczema and food allergy. Cochrane Database Syst Rev 2022;11:CD013534. https://doi.org/10.1002/14651858.CD013534.pub3.
  29. Grześk-Kaczyńska M, Petrus-Halicka J, Kaczyński S, et al. Should Emollients Be Recommended for the Prevention of Atopic Dermatitis? - New Evidence and Current State of Knowledge. J Clin Med 2024;13:863. https://doi.org/10.3390/jcm13030863.
  30. Hon KL, Kung JSC, Ng WGG, et al. Emollient treatment of atopic dermatitis: latest evidence and clinical considerations. Drugs Context. 2018;7:212530. https://doi.org/10.7573/dic.212530.
  31. Blume-Peytavi U, Lavender T, Jenerowicz D, et al. Recommendations from a European Roundtable Meeting on Best Practice Healthy Infant Skin Care. Pediatr Dermatol 2016;33:311-21. https://doi.org/10.1111/pde.12819.
  32. Boussault P, Léauté-Labrèze C, Saubusse E, et al. Oat sensitization in children with atopic dermatitis: prevalence, risks and associated factors. Allergy 2007;62:1251-1256. https://doi.org/10.1111/j.1398-9995.2007.01527.x.
  33. Pigatto P, Bigardi A, Caputo R, et al. An evaluation of the allergic contact dermatitis potential of colloidal grain suspensions. Am J Contact Dermat 1997;8:207-209.
  34. Togashi Y, Inomata N, Suzuki A, et al. Pediatric case with rice bran allergy induced by epicutaneous sensitization in a family rice shop. Allergol Int 2019;68:117-118. https://doi.org/10.1016/j.alit.2018.05.010.
  35. Li L, Han Z, Niu X, et al. Probiotic supplementation for prevention of atopic dermatitis in infants and children: a systematic review and meta-analysis. Am J Clin Dermatol 2019;20:367-377. https://doi.org/10.1007/s40257-018-0404-3.
  36. Wang L, Xu L. The impact of prebiotics, probiotics and synbiotics on the prevention and treatment of atopic dermatitis in children: an umbrella meta-analysis. Front Pediatr 2025;13:1498965. https://doi.org/10.3389/fped.2025.1498965.
  37. Fiocchi A, Pawankar R, Cuello-Garcia C, et al. World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Probiotics. World Allergy Organ J 2015;8:4. https://doi.org/10.1186/s40413-015-0055-2.
  38. Boyle RJ, Ismail IH, Kivivuori S, et al. Lactobacillus GG treatment during pregnancy for the prevention of eczema: a randomized controlled trial. Allergy 2011;66:509-516. https://doi.org/10.1111/j.1398-9995.2010.02507.x.
  39. Wickens K, Stanley TV, Mitchell EA, et al. Early supplementation with Lactobacillus rhamnosus HN001 reduces eczema prevalence to 6 years: does it also reduce atopic sensitization? Clin Exp Allergy 2013;43:1048-1057. https://doi.org/10.1111/cea.12154.
  40. Wickens K, Barthow C, Mitchell EA, et al. Maternal supplementation alone with Lactobacillus rhamnosus HN001 during pregnancy and breastfeeding does not reduce infant eczema. Pediatr Allergy Immunol 2018;29:296-302. https://doi.org/10.1111/pai.12874.
  41. Palmer DJ, Cuthbert AR, Sullivan TR, et al. Effects of pregnancy and lactation prebiotics supplementation on infant allergic disease: a randomized controlled trial. J Allergy Clin Immunol 2025;155:144-152. https://doi.org/10.1016/j.jaci.2024.08.009
  42. Kalliomäki M, Salminen S, Arvilommi H, et al. Probiotics in primary prevention of atopic disease: a randomised placebo-controlled trial. Lancet 2001;357:1076-1079. https://doi.org/10.1016/S0140-6736(00)04259-8
  43. Dissanayake E, Tani Y, Nagai K, et al. Skin care and synbiotics for prevention of atopic dermatitis or food allergy in newborn infants: a 2 × 2 factorial, randomized, non-treatment controlled trial. Int Arch Allergy Immunol 2019;180:202-211. https://doi.org/10.1159/000501636.
  44. Dotterud CK, Storrø O, Johnsen R, et al. Probiotics in pregnant women to prevent allergic disease: a randomized, double-blind trial. Br J Dermatol 2010;163:616-623. https://doi.org/10.1111/j.1365-2133.2010.09889.x.
  45. Kim JY, Kwon JH, Ahn SH, et al. Effect of probiotic mix in the primary prevention of eczema: a double-blind, randomized, placebo-controlled trial. Pediatr Allergy Immunol 2010;21:e386-e393. https://doi.org/10.1111/j.1399-3038.2009.00958.x.
  46. Allen SJ, Jordan S, Storey M, et al. Probiotics in the prevention of eczema: a randomised controlled trial. Arch Dis Child 2014;99:1014-1019. https://doi.org/10.1136/archdischild-2013-305799.
  47. Abrahamsson TR, Jakobsson T, Böttcher MF, et al. Probiotics in prevention of IgE-associated eczema: a double-blind, randomized, placebo-controlled trial. J Allergy Clin Immunol 2007;119:1174-1180. https://doi.org/10.1016/j.jaci.2007.01.007.
  48. Kopp MV, Hennemuth I, Heinzmann A, et al. Randomized, double-blind, placebo-controlled trial of probiotics for primary prevention: no clinical effects of Lactobacillus GG supplementation. Pediatrics 2008;121:e850-e856. https://doi.org/10.1542/peds.2007-1492.
  49. Cabana MD, McKean M, Caughey AB, et al. Early probiotic supplementation for eczema and asthma prevention: a randomized controlled trial. Pediatrics 2017;140:e20163000. https://doi.org/10.1542/peds.2016-3000.
  50. West CE, Hammarström ML, Hernell O. Probiotics during weaning reduce the incidence of eczema. Pediatr Allergy Immunol 2009;20:430-437. https://doi.org/10.1111/j.1399-3038.2009.00745.x.
  51. Schmidt RM, Laursen RP, Bruun S, et al. Probiotics in late infancy reduce the incidence of eczema: a randomized controlled trial. Pediatr Allergy Immunol 2019;30:335-340. https://doi.org/10.1111/pai.13018.
  52. Di Pierro F, Colombo M, De Giudici A, et al. Effect of supplementation with a specific probiotic (Bifidobacterium bifidum PRL2010) in pregnancy for the prevention of atopic dermatitis in children: preliminary results of a randomized trial. Nutrients 2025;17:673. https://doi.org/10.3390/nu17040673.
  53. Chen K, Jin S, Nie Y, et al. Efficacy of Bifidobacterium lactis BLa80 in preventing early childhood eczema and respiratory infections via gut microbiome and immune modulation. Front Nutr 2026;13:1727191. https://doi.org/10.3389/fnut.2026.1727191.
  54. Moro G, Arslanoglu S, Stahl B, et al. A mixture of prebiotic oligosaccharides reduces the incidence of atopic dermatitis during the first six months of age. Arch Dis Child 2006;91:814-819. https://doi.org/10.1136/adc.2006.098251.
  55. Boyle RJ, Tang MLK, Chiang WC, et al. Prebiotic-supplemented partially hydrolysed cow milk formula for the prevention of eczema in high-risk infants: a randomized controlled trial. Allergy 2016;71:701-710. https://doi.org/10.1111/all.12848.
  56. Myles IA, Earland NJ, Anderson ED, et al. First-in-human topical microbiome transplantation with Roseomonas mucosa for atopic dermatitis. JCI Insight 2018;3:e120608. https://doi.org/10.1172/jci.insight.120608.
  57. Myles IA, Castillo CR, Barbian KD, et al. Therapeutic responses to Roseomonas mucosa in atopic dermatitis may involve lipid-mediated TNF-related epithelial repair. Sci Transl Med 2020;12:eaaz8631. https://doi.org/10.1126/scitranslmed.aaz8631.
  58. Jacobson ME, Myles IA, Paller AS, et al. A randomized, double-blind, placebo-controlled, multicenter, 16-week trial to evaluate the efficacy and safety of FB-401 in subjects aged 2 years and older with mild-to-moderate atopic dermatitis. Dermatology 2024;240:85-94. https://doi.org/10.1159/000532054.
  59. Thomas KS, Koller K, Dean T, et al. A multicentre randomised controlled trial and economic evaluation of ion-exchange water softeners for the treatment of eczema in children: the Softened Water Eczema Trial (SWET). Health Technol Assess 2011;15:1-156. https://doi.org/10.3310/hta15080.
  60. Pelucchi C, Galeone C, Bach JF, La Vecchia C, Chatenoud L. Pet exposure and risk of atopic dermatitis at the pediatric age: a meta-analysis of birth cohort studies. J Allergy Clin Immunol 2013;132:616-622.e7. https://doi.org/10.1016/j.jaci.2013.04.009.
  61. Indolfi C, D’Addio E, Bencivenga CL, et al. The primary prevention of atopy: does early exposure to cats and dogs prevent the development of allergy and asthma in children? A comprehensive analysis of the literature. Life (Basel) 2023;13:1859. https://doi.org/10.3390/life13091859.
  62. Okada H, Kuhn C, Feillet H, et al. The ‘hygiene hypothesis’ for autoimmune and allergic diseases: an update. Clin Exp Immunol.2010;160:1-9. https://doi.org/10.1111/j.1365-2249.2010.04139.x.
  63. Kalliomäki M, Salminen S, Poussa T, et al. Probiotics and prevention of atopic disease: 4-year follow-up of a randomised placebo-controlled trial. Lancet 2003;361:1869-1871. https://doi.org/10.1016/S0140-6736(03)13490-3.
  64. Kim J, Kim BE, Ahn K, et al. Skin Predictive Biomarkers for the Development of Atopic Dermatitis and Food Allergy in Infants. Allergy Asthma Immunol Res 2024;16:323-337. https://doi.org/10.4168/aair.2024.16.4.323.
  65. Kim J, Shin S, Kim BE, et al. Skin barrier as a target for the prediction, prevention, and treatment of atopic dermatitis and food allergy in infancy. Pediatr Allergy Immunol 2025;36:e70238. https://doi.org/10.1111/pai.70238.
  66. Indolfi C, Grella C, Klain A, et al. Biomarkers in atopic dermatitis in children: a comprehensive review. Life (Basel) 2025;15:375. https://doi.org/10.3390/life15030375.
  67. Lack G. Epidemiologic risks for food allergy. J Allergy Clin Immunol 2008;121:1331-6. https://doi.org/10.1016/j.jaci.2008.04.032.
  68. Du Toit G, Roberts G, Sayre PH, et al.; LEAP Study Team. Randomized trial of peanut consumption in infants at risk for peanut allergy. N Engl J Med 2015;372:803-813. https://doi.org/10.1056/NEJMoa1414850. Erratum in: N Engl J Med 2016;375:398. https://doi.org/10.1056/NEJMx150044.
  69. Williams HC, Schmitt J, Thomas KS, et al; HOME Initiative. The HOME Core outcome set for clinical trials of atopic dermatitis. J Allergy Clin Immunol 2022;149:1899-1911. https://doi.org/10.1016/j.jaci.2022.03.017.
  70. D’Auria E, Indolfi C, Acunzo M, et al. Biologics and small molecules: the re-evolution in the treatment of atopic dermatitis in children and adolescents. Expert Rev Clin Immunol 2025;21:493-505. https://doi.org/10.1080/1744666X.2025.2452247.
  71. Indolfi C, Klain A, Dinardo G, et al. The dawn of a new era for biological drugs in allergology. Italian Journal of Pediatric Allergy and Immunology 2024;38(03):14-16. https://doi.org/10.53151/2531-3916/2024-508.

Downloads

pdf
Authors

Salvatore Cascone - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

Angela Klain - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

Carolina Grella - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

Valentina Cattivera - Department of Pediatrics, University of L’Aquila, L’Aquila, Italy

Cecilia Fabiano - Department of Pediatrics, University of L’Aquila, L’Aquila, Italy

Francesca Galletta - Pediatric Unit, Department of Human Pathology in Adult and Developmental Age ‘Gaetano Barresi’, University of Messina, Messina, Italy

Sara Manti - Pediatric Unit, Department of Human Pathology in Adult and Developmental Age ‘Gaetano Barresi’, University of Messina, Messina, Italy

Antonio Andrea Senatore - Pediatric Clinic, Fondazione IRCCS Policlinico, 27100 Pavia, Italy

Amelia Licari - Pediatric Clinic, Fondazione IRCCS Policlinico, Pavia, Italy

Michele Miraglia del Giudice - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

Gian Luigi Marseglia - Pediatric Unit, Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy

Cristiana Indolfi - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

on behalf of SIAIP Primary and Secondary Prevention of Allergic Diseases Commission - SIAIP Primary and Secondary Prevention of Allergic Diseases Commission

License

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Copyright

Copyright (c) 2026 Italian Journal of Pediatric Allergy and Immunology

How to Cite
Cascone, S., Klain, A., Grella, C., Cattivera, V., Fabiano, C., Galletta, F., Manti, S., Senatore, A. A., Licari, A., Miraglia del Giudice, M., Marseglia, G. L., Indolfi, C., & SIAIP Primary and Secondary Prevention of Allergic Diseases Commission, on behalf of . (2026). Skin barrier and cutaneous microbiota in the primary prevention of atopic dermatitis: current evidence and future perspectives. Italian Journal of Pediatric Allergy and Immunology, 40(3). https://doi.org/10.53151/2531-3916/2026-2768
  • Abstract viewed - 0 times
  • pdf downloaded - 0 times